Eccentricity measuring gauge and method for attaching a nesting washer using the same

Abstract

This invention provides a method for attaching insert washers to a base plate where the anchor bolt insertion holes are enlarged, and an eccentricity measuring gauge. [Solution] A base point 34 is provided on the upper surface of the seat at the position where the thickness of the cylindrical leg portion 32 of the main washer 30 is minimized, and the line connecting the center D of the enlarged hole 4 and the axis C of the anchor bolt 3 is extended in the eccentric direction to form an eccentric line. <ld>Set the angle and press the recess 11 of the eccentricity measuring gauge 10 against the circumferential surface of the anchor bolt 3, so that one side 11a of the plate-shaped body 11 is aligned with the eccentricity line. <ld>With the alignment correct, the eccentricity distance E of the anchor bolt 3 was measured from the difference in the values ​​on scale 13. The rotation angle θ of the lower washer was confirmed from the measured eccentricity distance E using a graph showing the relationship between the eccentricity distance E and the rotation angle θ, which was created for each size of the insert washer. An installation reference point 35(F) was set at the position of the rotation angle θ relative to the base point 34 of the main washer 30, and this was set as the eccentricity line. <ld>The mark above The cylindrical leg portion 32 of the main washer 30 is inserted into the enlarged hole 4 at the same position. < / ld> < / ld> < / ld>

Description

Technical Field

[0002] , ,

[0004] , , , , ,

[0003]

[0001] The present invention relates to a mounting technique for a nested washer used for tightening an anchor bolt, which is mounted in an enlarged hole for inserting an anchor bolt of a base plate fixed to the lower end of a steel column in an exposed column base used in a building such as a steel frame structure or a steel frame reinforced concrete structure.

Background Art

[0002] ​​​​​​​​These nesting washers, consisting of two washers of different sizes (hereinafter referred to as nesting washers), have a flange-like portion at the top of the eccentric cylindrical part (leg portion) of both the sub-washer and the main washer, with the smaller diameter upper washer fitted inside the larger diameter lower washer. When the nesting washers are installed in the enlarged anchor bolt insertion holes of the base plate, the total clearance between each component (in the lateral direction) is designed to be a maximum of 5 mm. Specifically, the total of the gap between the eccentric hole (anchor bolt receiving hole) of the sub-washer and the anchor bolt, the gap between the eccentric hole (leg receiving hole) of the main washer into which the leg portion of the sub-washer fits and the leg portion of the sub-washer, and the gap between the anchor bolt insertion hole (enlarged hole) of the base plate and the leg portion of the main washer must be within 5 mm. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 10-213123 (see Figures 2, 6, and 7) [Patent Document 2] Japanese Patent Publication No. 2007-57004 (see Figure 8) [Patent Document 3] Japanese Patent Publication No. 7-292772 (see Figure 2) [Patent Document 4] Japanese Patent Publication No. 6-74227 (see Figure 1)

[0006] The washers described above are nested in a set of two disc-shaped washers, one large and one small, stacked on top of each other. These washers share a common form, with a cylindrical leg on the underside of the disc-shaped base. At an eccentric position from the center of the base, the main washer has a hole for fitting the cylindrical leg of the upper washer, and the small washer has a hole for inserting the anchor bolt, with these holes penetrating the base and cylindrical leg, respectively. In this case, the cylindrical leg of the small washer is fitted into the eccentric hole of the main washer with a predetermined clearance, allowing relative rotation in the circumferential direction of the bolt or hole. During steel frame construction, if the position of the anchor bolt protruding from the top surface of the foundation concrete deviates from the design value, these washers can be rotated left and right to adjust their relative positions, allowing the washer to be installed in the anchor bolt insertion hole (enlarged hole) of the base plate with the anchor bolt passing through it.

[0007] Furthermore, this type of nesting washer has the advantage that when shear force is applied to the base plate due to earthquakes or wind, that shear force can be properly transmitted to the anchor bolts via the legs on the underside of the washer, as the cylindrical legs of the upper and lower washers fit almost seamlessly into the anchor bolt insertion holes in the base plate, which are formed as enlarged holes. In other words, by using nesting washers, it is possible to eliminate installation errors (deviations from the reference position) of anchor bolts within the range of an acceptable eccentricity distance, and to avoid problematic measures such as "leveling the base" or "on-site redrilling of the anchor bolt insertion holes in the base plate," which were said to have been performed in some cases. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Incidentally, the most common use of the insert washers described in the above-mentioned Patent Documents 1 to 4 is at the base of columns, but they are also used in seismic reinforcement, post-installed anchors, bridges, and bridge collapse prevention devices. In the case of column bases among these uses, if the anchor bolt is not installed in the center of the enlarged hole in the base plate, i.e., is eccentric, the main washer is first rotated in an appropriate direction to find a position in which its cylindrical leg can be fitted into the enlarged hole in the base plate fixed to the lower end of the steel column. Next, with the sub-washer inserted through the anchor bolt, its cylindrical leg is rotated in the same way and fitted into the leg receiving hole of the lower washer. This installation work is generally performed downwards within the range of visual inspection, so it is not particularly difficult to install the insert washers, but because it is done by feel, it is not very efficient, and improvement in workability was desired.

[0009] Furthermore, upward installation is more difficult than downward installation due to significant constraints on the installation location and posture. Specifically, because the nesting washer is installed against gravity, it is difficult to install while observing the installation position, as can be done in downward installation by placing the main washer first and then stacking the smaller washer on top. In particular, the difficulty increases dramatically when the installation space is narrow and the work is done in a blind state.

[0010] The present invention was created to solve the problems of the prior art described above, and aims to provide an eccentricity measuring gauge that can easily and accurately measure the eccentricity distance when an anchor bolt is eccentric in a base plate in which the anchor bolt insertion hole is formed as an enlarged hole, and a method for efficiently attaching an insert washer using this gauge. [Means for solving the problem]

[0011] As a technical means to solve the above problems, the invention according to claim 1 of the present application is an eccentricity measuring gauge used in a method of attaching an insert washer, in which the insert washer is used in a state A distinctive feature of this design is that it employs a configuration in which, for an anchor bolt that penetrates an enlarged hole in the base plate and stands upright on the upper surface, a recess is provided on one side of the plate-shaped body into which the bolt can be fitted in a semicircular shape in cross-section toward its axis from the circumferential side, and a scale is formed from the two opening edges of the recess located on one side of the plate-shaped body toward both ends of the plate-shaped body, with the center of the opening width as the starting point.

[0012] This invention focuses on the relationship between the distance from the center of the enlarged hole in the base plate to the axis of the anchor bolt, i.e., the eccentricity distance of the anchor bolt, and the rotation angle of the insert washer, in cases where the anchor bolt is misaligned. The key point is to prepare a graph in advance showing the relationship for each size of insert washer provided according to the diameter of the anchor bolt, to confirm the rotation angle of the main washer according to the eccentricity distance of the anchor bolt measured at the construction site, and to insert it into the enlarged hole in the base plate at the appropriate position based on that rotation angle. The rotation angle obtained from the graph is determined by setting a base point (in the embodiment,) at the position where the wall thickness is minimum in the cylindrical leg portion of the main washer, which is formed as an eccentric hole and has a continuously changing wall thickness. <np>This is referred to as the angle to the right or left relative to the ( ), and this is set on the upper surface near the peripheral edge of the seat portion of the main washer, or on the peripheral surface, and the installation reference point (in this embodiment, <f>It shall be referred to as such.)

[0013] In the installation of these insert washers, the ability to accurately and easily measure the eccentricity distance at the construction site improves work efficiency. The eccentricity measuring gauge according to the present invention has a recess on one side of the main body into which an anchor bolt, which stands upright on the upper surface side after passing through an enlarged hole in the base plate, can be fitted from the circumferential side toward the axis by a semicircular cross-section. Examples of the shape of the recess include a semicircle corresponding to half the cross-section of the target anchor bolt, or a rectangle whose opening (entrance) and depth are lengths corresponding to the diameter and radius of the anchor bolt, respectively. That is, it is important (essential requirement) that the opening width of the recess is equal to the diameter of the anchor bolt, and that when the anchor bolt is pushed in from the circumferential side to the back of the recess, the straight line connecting both ends of the recess entrance (opening edge) coincides with the diameter of the anchor bolt. Furthermore, on both sides of the recess, scales are formed from the two opening edges of the recess located on one side of the plate-shaped main body toward both ends of the plate-shaped main body, with the center of the opening width as the starting point. When using, with the anchor bolt inserted into the recess, the eccentric line (in the embodiment, <ld>This is referred to as [name of the eccentricity measurement gauge]. The eccentricity distance of the anchor bolt can be determined from the difference in the scale values ​​at two points where the periphery of the enlarged hole of the base plate intersects, using an eccentricity measuring gauge that is installed so as to straddle the enlarged hole of the base plate. Furthermore, as will be described later, the position of the eccentricity line can be easily determined by rotating the gauge left and right while applying it to the anchor bolt and measuring the maximum or minimum position of the gap between the outer surface of the anchor bolt and the inner surface of the enlarged hole of the base plate. By using an eccentricity measuring gauge with this configuration, it becomes possible to easily and accurately grasp the eccentricity of the anchor bolt.

[0014] The invention according to claim 2 of the present application comprises a pair of sub-washers and a main washer, each having a concentric cylindrical leg portion on the lower surface side of the seat portion, wherein the sub-washer has an anchor bolt receiving hole with an inner diameter matching the outer diameter of the anchor bolt, which penetrates the seat portion and the cylindrical leg portion at an eccentric position, and the main washer has a leg receiving hole with an inner diameter matching the outer diameter of the cylindrical leg portion of the sub-washer, which penetrates the seat portion and the cylindrical leg portion, which has an outer diameter matching the enlarged hole for anchor bolt insertion in the base plate, at an eccentric position, and the method for installing the insert washer involves inserting the cylindrical leg portion of the sub-washer into the leg receiving hole of the main washer and stacking them vertically, and then fitting the insert washer into the enlarged hole of the base plate with the anchor bolt inserted through the sub-washer, After extending the line connecting the center of the enlarged hole in the base plate and the axis of the anchor bolt that penetrates the enlarged hole in the base plate and stands upright on the upper surface to the upper surface of the base plate in the eccentric direction of the anchor bolt to form the eccentric line, an eccentricity measuring gauge is used, in which a recess is provided on one side of the plate-shaped body into which the anchor bolt can be fitted in a semicircular distance in cross-section from the circumferential side toward the axis, and a scale is formed from two opening edges of the recess located on one side of the plate-shaped body, with the scale starting from the center of the opening width toward both ends of the plate-shaped body, the anchor bolt is fitted into the recess and one side is aligned with the eccentric line, and the eccentricity distance is measured from the difference in the values ​​of the scales on both sides that straddle the enlarged hole in the base plate where the periphery of the enlarged hole is located, a base point is set at the position where the wall thickness of the cylindrical leg of the main washer is minimum in the circumferential direction, and an installation reference point is set on the seat at the position of the rotation angle read from the graph representing the relationship between the eccentricity distance and the rotation angle of the main washer, and the installation reference point coincides with the position on the eccentric side of the eccentric line (in this embodiment, This is referred to as [name of the component]. The configuration consists of inserting the cylindrical leg portion of the main washer into the enlarged hole of the base plate, then rotating the sub-washer to a predetermined position while it is inserted into the anchor bolt, and inserting the cylindrical leg portion of the sub-washer into the leg receiving hole of the main washer.

[0015] In the above mounting method, first, an eccentricity line is set by extending a line connecting the center of the enlarged hole in the base plate and the axis of the anchor bolt to the top surface of the base plate on the eccentric side of the anchor bolt. With the anchor bolt fitted into the recess of the eccentricity measuring gauge, one side with the scale is aligned with this eccentricity line. In this state, the scales on both sides are checked, and the eccentricity distance is measured based on the difference between these values. Then, the rotation angle corresponding to this eccentricity distance is checked against a pre-prepared graph. When setting the eccentricity line, the recess of the eccentricity measuring gauge is pressed against the anchor bolt and rotated slightly in the left and right directions. The position where the clearance between the outer surface of the anchor bolt and the inner surface of the enlarged hole in the base plate is maximum (minimum on the eccentric side) corresponds to the position where one side of the eccentricity measuring gauge coincides with the eccentricity line. Next, a reference point is set at the rotation angle read from the graph, relative to a base point located at the position where the thickness of the cylindrical leg of the main washer is minimized. The main washer is then positioned by inserting the cylindrical leg of the main washer into the enlarged hole of the base plate when this reference point coincides with the eccentricity line on the eccentric side. Subsequently, the sub-washer is inserted onto the anchor bolt and rotated on the upper surface of the lower washer. When it reaches the predetermined rotation angle, the cylindrical leg of the upper washer naturally fits into the leg receiving hole of the main washer. According to the method of the present invention, by using the eccentricity measuring gauge according to claim 1, the insert washer can be easily and reliably installed into the enlarged hole of the base plate, and the gap of the enlarged hole that has become excessively large can be filled with steel material, while also greatly contributing to improved workability. Note that the position where the cylindrical leg of the sub-washer fits into the leg receiving hole of the main washer is the same as the rotation angle of the main washer on the opposite side of the eccentricity line (however, the rotation is relative to the anchor bolt center). [Effects of the Invention]

[0016] In the present invention adopting the above configuration, when fitting a nested washer that can continuously cope from a state where there is no eccentricity of the anchor bolt to the maximum eccentricity position with respect to the anchor bolt eccentric within the enlarged hole (anchor bolt insertion hole) of the base plate, by using the eccentric holes provided in the child washer and the parent washer respectively, when grasping the relationship between the eccentricity distance and the rotation angle with respect to the base point provided at the minimum wall thickness position of the cylindrical leg portion of the parent washer at the position where they can be fitted to each other, by using the eccentric measurement gauge according to the present invention, the eccentricity distance can be easily measured, and an eccentricity line can be set, and the fitting operation of the nested washer can be performed more efficiently.

Brief Description of the Drawings

[0017] [Figure 1] It is a perspective view when the nested washer according to the present invention is applied to an exposed column base. [Figure 2] (a) and (b) are a plan view and a cross-sectional view of the child washer which is one of the constituent members of the nested washer used in the exposed column base of FIG. 1. [Figure 3] (a) to (c) are a plan view, a perspective view, and an A-A cross-sectional view of the parent washer which is the other constituent member of the nested washer used in the exposed column base of FIG. 1. [Figure 4] It is a cross-sectional view showing the fitting state of the nested washer composed of the anchor bolt located at the center of the enlarged hole and the child washer of FIG. 2 and the parent washer of FIG. 3. [Figure 5] It is a cross-sectional view showing the fitting state of the nested washer composed of the anchor bolt deviated from the center of the enlarged hole and the child washer of FIG. 2 and the parent washer of FIG. 3. [Figure 6] (a) and (b) are explanatory views showing the relationship between the positions of the eccentric holes in the cylindrical leg portions of the parent washer and the child washer and the position of the base point provided on the upper surface of the seat portion for the nested washer targeting an M27 anchor bolt. [Figure 7] It is an explanatory view showing the rotation angle from the eccentricity line when each member is fitted to each other in the range from a state where the anchor bolt is not eccentric (eccentricity distance 0 mm) to the maximum eccentricity state (eccentricity distance 11 mm) with respect to the enlarged hole of the base plate for the parent washer and the child washer of the nested washer of FIG. 6. [Figure 8] It is a graph showing the relationship between the eccentricity distance, which is the distance between the center of the enlarged hole of the base plate and the center of the anchor bolt, and the rotation angle for each state in FIG. 7. [Figure 9] (a) to (c) are a plan view, a front view, and a side view of an eccentricity measurement gauge according to a first embodiment of the present invention targeting a M24 anchor bolt. [Figure 10] It is a plan view showing a state where the eccentricity measurement gauge of FIG. 9 is applied when the anchor bolt is not eccentric. [Figure 11] It is a plan view showing a state where the eccentricity measurement gauge of FIG. 9 is applied when the anchor bolt is eccentric in the horizontal direction. [Figure 12] It is a plan view showing a state where the eccentricity measurement gauge of FIG. 9 is applied when the anchor bolt is eccentric in the upper right diagonal direction. [Figure 13] (a) to (c) are explanatory diagrams showing the procedure of measuring the eccentricity distance by the method of FIG. 12 and attaching the nested washer of FIG. 6 using the graph of FIG. 8. [Figure 14] They are a plan view and a front view when adjusting the eccentricity measurement gauge of FIG. 9 when the outer diameter of the anchor bolt is slightly small. [Figure 15] (a) and (b) are a plan view and a front view of an eccentricity measurement gauge according to a second embodiment of the present invention targeting a M24 anchor bolt.

Mode for Carrying Out the Invention

[0018] The embodiments of the present invention will be described below with reference to the attached drawings. Figure 1 is a perspective view showing the overall appearance of some anchor bolt fastening parts disassembled, in an example where the insert washer used in the present invention is applied to an exposed column base. The method of attaching the insert washer using an eccentricity measuring gauge, which is a characteristic feature of the present invention, will be explained in detail with reference to Figures 9 to 13 after the overall structure has been described. The exposed column base shown in the figure has a base plate 2 fixed to the lower end of a steel column 1, which is secured by anchor bolts 3 protruding from the upper surface of a foundation concrete (not shown). In this example, the base plate 2 has enlarged holes 4 formed at the four corners, which are approximately 22 to 50 mm larger than the diameter of the anchor bolt 3 to be used, according to the nominal diameter (M12 to M80) of the anchor bolt 3 to be used. Each anchor bolt 3 is fastened with two nuts 8, 8 with a washer 7, which consists of a combination of an insert washer 5 and a flat washer 6, as will be described in detail next, inserted through it.

[0019] Figures 2 and 3 show the sub-washer 20 and main washer 30, which are composed of two nesting washers 5. The sub-washer 20 shown in Figure 2 has a punch hole 22 on the upper surface of the disc-shaped seat 21, which will be used as a reference point for positioning later. <np>It is formed as a disc-shaped base, with cylindrical legs 23 formed concentrically on its lower surface. Furthermore, an anchor bolt receiving hole 24 with an inner diameter matching the shaft diameter of the anchor bolt 3 penetrates the base 21 and the cylindrical legs 23 at an eccentric position relative to the disc-shaped base 21.

[0020] As shown in Figure 3, the main washer 30 has a disc-shaped seat 31 that is larger in outer diameter than the seat 21 of the sub-washer 20. A cylindrical leg portion 32 with an outer diameter matching the inner diameter of the enlarged hole 4 of the base plate 2 is formed concentrically with the seat 31 on the lower side of the seat 31. A leg receiving hole 33 with an inner diameter matching the outer diameter of the cylindrical leg portion 23 of the sub-washer 20 penetrates both the seat 31 and the cylindrical leg portion 32 at an eccentric position relative to the seat 31. Furthermore, on the upper surface of the seat 31, a punch hole 34 is formed at the base point, similar to the sub-washer 20. <np>It is formed as follows.

[0021] The base point 22 of the sub-washer 20 and the base point 34 of the main washer 30 are located on the peripheral edge, radially outward from directly above the positions 23a and 32a of the minimum wall thickness t1 and t2 of the cylindrical leg portion 23 and cylindrical leg portion 32, respectively, which have eccentric holes on the inside. In this nest washer 5, t1 and t2 have the same wall thickness. These sub-washers 20 and main washers 30 are used as a nest washer 5 by inserting the cylindrical leg portion 23 of the sub-washer 20 into the leg portion receiving hole 33 of the main washer 30 and stacking their respective seat portions 21 and 31 vertically. <np>The positions of 22 and 34 may be on the circumferential surface of the seat, not just the top surface of the seat. Furthermore, it is possible to mark these positions with a marker pen or similar at the work site, not just during the washer's manufacturing process.

[0022] Next, the mechanism of the insert washer 5, which addresses misalignment of the anchor bolt by utilizing the eccentric holes of the two components, will be explained based on Figures 4 and 5. The figures show the relationship between the anchor bolt 3, the enlarged hole 4 of the base plate, and the insert washer 5, and are cross-sectional views taken at the positions of the respective cylindrical legs 23 and 32 to clearly show the mating state. In Figure 4, the anchor bolt 3 is located at the center of the enlarged hole 4 of the base plate 2. That is, the axis C of the anchor bolt 3 and the center D of the enlarged hole 4 of the base plate 2 coincide, and the anchor bolt 3 is installed as designed. In this case, the mating positions of the sub-washer 20 and the main washer 30 are limited, but as long as this mating state (relative position) is maintained, the cylindrical leg 32 of the main washer 30 can be fitted and attached to the enlarged hole 4 of the base plate 2 at any position in the circumferential direction.

[0023] However, as shown in Figure 5, if the axis C of the anchor bolt 3 is off-center D of the enlarged hole 4, the positional relationship between the enlarged hole 4 of the base plate 2, the sub-washer 20, and the main washer 30 becomes important, and it is not possible to install it unless it is in a specific position. In the conventional installation method, first the main washer 30 is rotated to insert its cylindrical leg portion 32 into the enlarged hole 4 of the base plate 2. Next, with the upper end of the anchor bolt 3 inserted into the anchor bolt receiving hole 24 of the sub-washer 20, the sub-washer 20 is rotated, and the main washer 30 is also rotated as appropriate to find the fitting position. When the fitting position is reached, the cylindrical leg portion 23 of the sub-washer 20 is completely immersed in the leg receiving hole 33 of the main washer 30, and at the same time, the upper end of the anchor bolt 3 is properly inserted into the anchor bolt receiving hole 24 of the sub-washer 20. Then, in this state, as shown in Figure 1, when the anchor bolt 3 is screwed with a double nut (a single nut may also be used) 8,8, the anchor bolt 3 fits into the enlarged hole 4 by the insert washer 5 (the sub-washer 20 and the main washer 30), and any misalignment is absorbed, firmly fixing the base plate 2.

[0024] Next, the insert washer 5 used in the present invention will be explained with specific examples, referring to Figures 6 and 7. The specifications of the insert washer vary depending on the size of the anchor bolt, but the most important requirement, the allowable maximum eccentricity distance Emax, can be expressed by the following formula. Emax = 2 × Eh + CL / 2 Eh: Center of the cylindrical leg portion of the sub-washer and main washer (center of each seat portion in Figure 6) Distance from A1,B1) to the center of the eccentric hole (A2,B2 in Figure 6) CL: Clearance of nesting washer (gap between anchor bolt and nesting washer + nesting washer) The gap between the cylindrical leg portion 23 of the gold plate 20 and the leg receiving hole 33 of the main washer gold plate 30 + main washer (The gap between the cylindrical leg portion 32 made of gold 30 and the enlarged hole 4 of the base plate 2)

[0025] A first embodiment of a nesting washer for M27 anchor bolts will be described in detail. As shown in Figures 6(a) and (b), when the distance Eh (hereinafter also referred to as the hole eccentricity distance) from the centers A1 and B1 of the cylindrical legs 23 and 32 (which are also the centers of the seat portions 21 and 31) to the centers A2 and B2 of the eccentric holes 24 and 33 of the sub-washer 20 and main washer 30 is set to 4.5 mm and the clearance CL is set to 4.0 mm, the maximum eccentricity distance Emax is 4.5 × 2 + 4.0 / 2 = 11 (mm). In this case, clearance CL is the result of calculating the gap using the manufacturing (standard) dimensions of each component. An example of OF-(L)17 provided by the applicant is as follows: (1) Distance between the inner diameter of the enlarged hole in the base plate (±0) and the outer diameter of the cylindrical leg of the main washer: 55.0 - 53.5 = 1.5 (mm) (2) Distance between the inner diameter of the leg receiving hole of the main washer and the outer diameter of the cylindrical leg of the sub-washer: 41.5 - 40.5 = 1.0 (mm) (3) Distance between the inner diameter of the anchor bolt receiving hole of the sub-washer and the outer diameter of the anchor bolt (±0): 28.5 - 27.0 = 1.5 (mm) Therefore, the calculated total clearance CL is 4.0 mm. Since the gap CL is distributed around the center, half of this is used as the clearance in one direction, and in addition to the eccentricity correction by the rotation of the sub-washers and main washers described later, it is added to the allowable eccentricity distance (maximum eccentricity distance Emax) due to the linear movement of both.

[0026] Figure 7 shows the fitting state of the sub-washer 20 and main washer 30 of the nesting washer in Figure 6, when the eccentricity distance E is changed by 1 mm increments from the state in which the anchor bolt 3 is not eccentric with respect to the enlarged hole 4 of the base plate 2 to the state of maximum eccentricity. That is, the figure with the number [0] in the upper right corner of each of the 12 divided frames represents the case where the eccentricity distance E = 0 mm, and similarly the figure with the number

[11] represents the case where the eccentricity distance E = 11 mm. The base point of the sub-washer 20 corresponding to the position of the minimum wall thickness portion 23a, 32a of each cylindrical leg portion 23, 32 ( <np>)22 (shown as a triangle in the diagram) and the base point of the main washer 30 ( <np>)34 (shown as ▲ in the diagram) is an eccentric line provided near the enlarged hole 4 of the base plate 2. <ld>This is an explanatory diagram showing the rotation angles θ1 and θ2, with θ set to 0°.

[0027] In Figure 7, when the eccentricity distance E = 9 mm is taken as the reference point [9], where the axis C of the anchor bolt 3 is shifted 9 mm to the right relative to the center D of the enlarged hole 4, the eccentricity line is defined as being eccentric up to the maximum eccentricity distance Emax = 11 mm. <ld>This position is obtained by moving in a straight line along the line. Under these conditions, the base point 22 of the sub-washer 20 and the base point 34 of the main washer 30 are on the eccentric line. <ld>It is located above. On the other hand, when the eccentricity distance E is less than 9 mm ([9]~[1]), the sub-washer 20 and the main washer 30 are aligned with the eccentricity line. <ld>The two washers need to rotate in opposite directions across the eccentricity line, and the rotation angles θ1 and θ2 increase as the eccentricity distance E decreases. For example, when the eccentricity distance E is 8 mm, the rotation angles θ1 and θ2 are 27°, and when the eccentricity distance E = 1 mm, the rotation angles θ1 and θ2 are 84°. At this time, the base point 22 of the sub-washer 20 and the base point 34 of the main washer 30 are on the eccentricity line. <ld>They are at the same angle with respect to each other. Furthermore, if the anchor bolt 3 is not eccentric, the base point 22 of the sub-washer 20 and the base point 34 of the main washer 30 are in symmetrical positions with respect to the center C of the anchor bolt 3 (which coincides with the center D of the enlarged hole 4).

[0028] In the fitted (mounted) state shown in Figure 7 [0] to

[11] , the distance from the center D of the enlarged hole 4 of the base plate 2 to the center C of the anchor bolt 3 (eccentricity distance E) and the eccentricity line at that time. <ld>The base point of the sub-washer 20 ( <np>) 22 and the base point of the main washer 30 ( <np>Figure 8 shows a graph illustrating the relationship between the positions of 34 and their rotation angles θ1 and θ2. As is clear from this graph, when anchor bolt 3 is not eccentric (E=0mm), base point 22 and base point 34 are on the eccentric line when the center D of the enlarged hole 4 is the axis of rotation. <ld>It is at a 90° angle to the eccentricity. In the range of eccentricity E from zero to 9.0 mm, the rotation angles θ1 and θ2 decrease as the eccentricity E increases, and when the eccentricity E = 9.0 mm, the rotation angles θ1 and θ2 become zero. Then, in the range of eccentricity E from 9.0 mm to the maximum allowable eccentricity of 11.0 mm, the eccentricity E is at 9.0 mm (the position of the base point 22 of the sub-washer 20 and the base point 34 of the main washer 30 is the eccentricity line). <ld>(matches) eccentric line <ld>This graph shows that the movement follows a straight line along the line.

[0029] In Figures 7 and 8, it is noteworthy that in the range of eccentricity distance E from 0 to 9 mm (twice the hole eccentricity distance Eh = 4.5 mm), the position can be determined by the rotation of the sub-washer 20 and the main washer 30. However, for eccentricity beyond this range, the position is determined by lateral movement, which is half of the clearance CL mentioned earlier, or a maximum of 2 mm (see

[10] and

[11] in the figures).

[0030] Figures 9(a) to 9(c) are a plan view, front view, and side view of an eccentricity measuring gauge according to a first embodiment of the present invention for M24 anchor bolts. The illustrated eccentricity measuring gauge 10 has a rectangular recess 12 cut out in the center of one side 11a of a plate-shaped body 11, scales 13 are provided on both sides of the recess 12, and a handle 14 is provided on the other side 11b. The rectangular (U-shaped) recess 12, consisting of a base 12a and a pair of opposite sides 12b, 12b, has an opening width W and a depth D that correspond to the diameter 24 mm and radius 12 mm of the anchor bolt, respectively. The scale 13 starts from the center of the opening width W, and since the outer diameter of the M24 anchor bolt to be used is 24 mm, it begins at 12 mm (the position of the opening edge 12c, which is the opening side end of the pair of opposite sides 12b and 12b), which is half the length of the opening width W, and is marked every 1 mm toward both ends in the longitudinal direction of the plate-shaped body 11.

[0031] Figures 10-12 show plan views of the eccentricity measuring gauge from Figure 9 when applied to the base plate in three states: when the anchor bolt is not eccentric relative to the enlarged hole, when it is 5 mm eccentric in the lateral direction, and when it is 5 mm eccentric in the upper right direction. In this case, the enlarged hole 4 in the base plate is set to a diameter of 50 mm.

[0032] In Figure 10, where the anchor bolt is in the correct position, the eccentric line <ld>There is no obstruction, and the center D of the enlarged hole 4 coincides with the axis C of the anchor bolt 3. When the eccentricity measuring gauge 10 is placed against the anchor bolt 3 on the upper surface of the base plate so as to contact the bottom edge 12a of the recess 12, the periphery of the enlarged hole 4 is located at two points, each at a scale value of 25 mm.

[0033] In Figure 11, which is eccentric in the lateral direction, the line connecting the center D of the enlarged hole 4 and the axis C of the anchor bolt 3 is first extended in both directions to the upper surface of the base plate to form the eccentric line. <ld>Next, position the eccentricity measuring gauge 10 so that its recess 12 contacts the base 12a of the anchor bolt 3, and the side 11a of the plate-shaped body 11 is aligned with the eccentricity line. <ld>Install it so that it matches the position. In this case, the periphery of the enlarged hole 4 of the base plate is located 20 mm on the eccentric side and 30 mm on the opposite side, so the eccentricity distance E is 5 mm, which is half the difference.

[0034] Figure 12 shows a state of eccentricity towards the upper right. Similar to Figure 11, the line connecting the center D of the enlarged hole 4 and the axis C of the anchor bolt 3 is extended in both directions to the upper surface of the base plate to form the eccentricity line. <ld>Set this eccentricity line in this inclined state. <ld>In this case, the anchor bolt 3 is positioned so that its circumferential surface contacts the bottom edge 12a of the recess 12, and one side 11a of the eccentricity measuring gauge 10 is aligned with it. In this case as well, similar to Figure 11, the periphery of the enlarged hole 4 of the base plate is located 20 mm on the eccentric side and 30 mm on the opposite side, so the eccentricity distance E is 5 mm, which is half the difference.

[0035] Note: eccentric line <ld> When setting this up, mark the upper surface of the base plate on the eccentric side near the enlarged hole 4 with a marker pen or similar to serve as a guide for installing the main washer of the subsequent insert washer.< / ld> < / ld> < / ld> < / ld> < / ld> < / ld> < / ld> < / ld> < / ld> < / np> < / np> < / ld> < / ld> < / ld> < / ld> < / ld> < / ld> < / np> < / np> < / np> < / np> < / np> Leave this mark on. is an eccentric line <ld> In cases where it is not actually drawn, a rotation reference point to represent the installation position and direction of eccentricity< / ld> This is necessary. Also, when measuring the eccentricity distance E, one side 11a of the eccentricity measuring gauge 10 is used as the eccentricity line. <ld>It is important to match this. To identify the eccentricity line, as shown in Figure 12, it is effective to rotate the eccentricity measuring gauge 10 slightly in the left-right direction (indicated by R) while applying it so that the circumferential surface of the anchor bolt 3 is in contact with the bottom edge 12a of the recess 12, and to identify the position where the gaps on both sides show the maximum and minimum values, respectively. In other words, the rotation position in the gap opposite to the right-upward diagonal direction (eccentricity direction) in which the anchor bolt 3 is eccentric, where the gap CL1 (clearance) between the inner circumferential surface of the enlarged hole 4 and the outer circumferential surface of the anchor bolt 3 is maximum, corresponds to the eccentricity line of one side 11a of the eccentricity measuring gauge 10. <ld>This results in a state where the two values ​​match. In this case, the scale value is 30mm, and the interval CL1 is 30-12=18mm. Alternatively, one could select the rotation position that is smallest on the eccentric side where the interval CL2 is narrower, which corresponds to the scale value of 20mm. The interval CL2 would then be 20-12=8mm.

[0036] Figures 13(a) to (c) show the measurement of the eccentricity distance E and the eccentricity line using the method in Figure 12. <ld>This is an explanatory diagram showing the procedure for setting up and attaching the insert washer exemplified in Figure 6 to the enlarged hole 4 of the base plate. In Figure 13(a), the anchor bolt 3 is eccentrically positioned diagonally upward to the right relative to the enlarged hole 4 of the base plate, and the positional relationship is shown when the eccentricity distance E from the center D of the enlarged hole 4 to the axis C of the anchor bolt 3 is 5 mm. When measuring the eccentricity distance E, the eccentricity line of the position takes into account the diameter of the seat portion 31 of the main washer 30. <ld> Mark the top with a marker pen or similar.< / ld> < / ld> < / ld> < / ld> Attach it. Specifically, a suitable position is approximately 25 mm away from the edge of the enlarged hole 4 in the base plate.

[0037] Next, as shown in (b), for the main washer 30, read the rotation angle of 56° corresponding to E=5mm from the graph (Figure 8) showing the relationship between the eccentricity distance E and the rotation angles θ1 and θ2, and mark a base point ( <np>)34 (Indentation made with a punch, mark made with a marker pen, etc.) The reference point 35 is set at a position 56° clockwise relative to this mark. <f>) is marked with a marker pen or similar, and this installation reference point 35( <f>) is the eccentric line <ld> The mark that was set< / ld> < / f> < / f> < / np> The cylindrical leg portion 32 of the main washer 30 is inserted into the enlarged hole 4 of the base plate 2 at a position that matches the above.

[0038] On the other hand, as shown in (c), the sub-washer 20 is positioned with the anchor bolt 3 inserted through the anchor bolt receiving hole 24 and its cylindrical leg portion 23 resting on the seat portion 32 of the main washer 30, and its base point ( <np>)22 is the eccentric line <ld> The mark above< / ld> < / np> When rotated 56° clockwise from its original position, the cylindrical leg portion 23 of the sub-washer 20 fits into the leg receiving hole 33 of the main washer 30, completing the installation.

[0039] By the way, once the main washer 30 is installed in the correct position, the cylindrical leg 23 of the sub-washer 20 will naturally fit into the leg receiving hole 33 of the main washer 30 during one rotation while inserted through the anchor bolt 3. In construction methods that satisfy this requirement, the base point of the sub-washer 20 ( <np>)22 is not a mandatory requirement. The position in which the cylindrical leg portion 23 of the sub-washer 20 can finally be fitted into the leg receiving hole 33 of the main washer 30 is, as described above, the eccentric line. <ld>Since the sub-washer 20 is only in a position with the same rotation angle as the upper washer 20, even if there is no base point 22 for the sub-washer 20, or even if it does not rely on the base point 22, it will fit naturally during one rotation, making installation easy. In other words, in the installation of this type of nesting washer, it is especially important how quickly and accurately the main washer 30 can be positioned.

[0040] Note that in Figure 13(C), the eccentricity line <ld>Although the rotation angles θ1 and θ2 with respect to the same point do not appear to be the same, this is because the rotation axes of the sub-washer 20 and the main washer 30 are different, but the angles are the same. Furthermore, the clearance created between the mounting members by the rotation of the sub-washer 20 and the main washer 30 is uniform around the entire circumference as shown in the figure. In this invention, the main washer 30, which must be positioned first, has a base point ( <np>)34 is used to set the rotation angle θ1 based on the eccentricity distance E to the reference point 35( <f>) is displayed as this installation reference point 35( <f>) is set as the eccentric line of anchor bolt 3. <ld>A key feature is its ability to align with the target, and combined with the use of the eccentricity measuring gauge mentioned above, it improves the installation process of the insert washer.

[0041] Figure 14 shows an application example of the eccentricity measuring gauge according to the first embodiment of Figure 9. This eccentricity measuring gauge 10 can be applied to anchor bolts 3 that are manufactured with a smaller outer diameter by evenly attaching tape 15 for thickness adjustment to the center of the base 12a and near the opening edges 12c of each of the pair of opposite sides 12b, 12b.

[0042] Figure 15 shows a second embodiment of the eccentricity measuring gauge according to the present invention. This eccentricity measuring gauge 16 is characterized in that the recess 17 is formed in a semicircular shape, and the other parts are the same as those of the second embodiment.

[0043] In each of the above embodiments, both the sub-washer 20 and the main washer 30 have a base point ( <np>Although the example shows the case where 22 and 34 are provided, once the position of the main washer 30 is determined, the position of the sub-washer 20 is also determined, and it can be fitted within a range of one rotation, so even just having a base point 22 on the main washer 30 will improve the installation process. As a specific example of base points 22 and 34, a mortar-shaped recess made with a punch was described, but it can be changed to other shapes such as arrow shapes or straight lines, and the means of providing them can also be other than stamping, such as coating or cutting.

[0044] It should be noted that the present invention is not limited to the above embodiments, and the hole eccentricity distance and clearance amount in the insert washer can be set arbitrarily. Furthermore, its application is not limited to column bases, and it can be modified and implemented in various locations within the technical concept of the present invention. [Industrial applicability]

[0045] The eccentricity measuring gauge and the method for attaching the insert washer using it according to the present invention demonstrate their advantages when used in structures such as steel-framed buildings, and further development is expected as a means to improve the installation process. [Explanation of Symbols]

[0046] 1...Steel column, 2...Base plate, 3...Anchor bolt, 4...Enlarged hole, 5...Insert washer, 6...Flat washer, 7...Washer, 8...Nut, 10,16...Eccentricity measuring gauge, 11...Plate-shaped body, 12,17...Recess, 13...Scale, 14...Handle, 15...Tape, 20...Small washer, 22,34...Punch hole (base point) <np>), 23, 32... cylindrical leg portion, 24... anchor bolt receiving hole, 30... main washer, 33... leg portion receiving hole, 35, <f>...Installation reference point, A1, B1...Center of cylindrical leg, B1, B2...Center of eccentric hole, C...Axis of anchor bolt, D...Center of enlarged hole, <ld> ...eccentric line,< / ld> < / f> < / np> < / np> < / ld> < / f> < / f> < / np> < / ld> < / ld> < / np> ...mark (rotation reference point) < / ld> < / f> < / np>

Claims

1. An eccentricity measuring gauge used in a method of installing an insert washer, which consists of a pair of insert washers, a sub-washer and a main washer, each having concentric cylindrical legs on the underside of the seat, the sub-washer having an anchor bolt receiving hole with an inner diameter matching the outer diameter of the anchor bolt, which penetrates the seat and the cylindrical leg at an eccentric position, and the main washer having a leg receiving hole with an inner diameter matching the outer diameter of the cylindrical leg of the sub-washer, which penetrates the seat and the cylindrical leg, which has an outer diameter matching the enlarged hole for inserting the anchor bolt in the base plate, at an eccentric position, and the insert washer used by inserting the cylindrical leg of the sub-washer into the leg receiving hole of the main washer and stacking them vertically, and then fitting the insert washer into the enlarged hole of the base plate with the anchor bolt inserted through the sub-washer. An eccentricity measuring gauge characterized in that, for the anchor bolt that penetrates the enlarged hole in the base plate and stands upright on the upper surface side, a recess is provided on one side of the plate-shaped body into which the anchor bolt can be fitted by a semicircular amount in cross-section toward the axis from the circumferential side, and a scale is formed from two opening edges of the recess located on one side of the plate-shaped body toward both ends of the plate-shaped body, with the center of the opening width as the starting point.

2. The nesting washer consists of a pair of sub-washers and a main washer, each having concentric cylindrical legs on the underside of the seat portion. The sub-washer has an anchor bolt receiving hole with an inner diameter matching the outer diameter of the anchor bolt, which penetrates the seat portion and the cylindrical leg portion at an eccentric position. The main washer has a leg receiving hole with an inner diameter matching the outer diameter of the cylindrical leg portion of the sub-washer, which penetrates the seat portion and the cylindrical leg portion, which has an outer diameter matching the enlarged hole for inserting the anchor bolt in the base plate, at an eccentric position. The method for installing the nesting washer involves inserting the cylindrical leg portion of the main washer into the leg receiving hole of the main washer and stacking them vertically, and then fitting the nesting washer into the enlarged hole of the base plate with the anchor bolt inserted through the sub-washer. After extending the line connecting the center of the enlarged hole in the base plate and the axis of the anchor bolt that penetrates the enlarged hole in the base plate and stands upright on the upper surface to the upper surface of the base plate in the eccentric direction of the anchor bolt to form an eccentric line, an eccentricity measuring gauge is used, in which the anchor bolt is fitted into the recess of the plate-shaped body by a semicircular amount in cross-section from the circumferential side toward the axis, and a scale is formed from two opening edges of the recess located on one side of the plate-shaped body, with the scale starting from the center of the opening width toward both ends of the plate-shaped body, the anchor bolt is fitted into the recess of the eccentricity measuring gauge and with one side aligned with the eccentric line, and the base plate is used. A method for installing a nesting washer, characterized by measuring the eccentricity distance from the difference between the numerical values ​​on both sides of the enlarged hole in the base plate where the periphery of the enlarged hole is located, setting an installation reference point on the seat at the position of the rotation angle read from a graph representing the relationship between the eccentricity distance and the rotation angle of the main washer, with respect to a base point set at the position where the wall thickness of the cylindrical leg of the main washer is minimum in the circumferential direction, inserting the cylindrical leg of the main washer into the enlarged hole in the base plate at a position where the installation reference point coincides on the eccentric side of the eccentricity line, and then rotating the sub-washer to a predetermined position with the sub-washer inserted into the anchor bolt so that the cylindrical leg of the sub-washer fits into the leg receiving hole of the main washer.

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