Stepladder type induction antenna stand and induction antenna installation method using stand

Abstract

To provide a stepladder type induction antenna stand which can be stably and firmly installed even on an uneven ground by using a commercially available stepladder, and which comprises a jig that allows the angle of the induction antenna to be adjusted in the front-rear direction, the height position to be adjusted up and down, and the antenna to be slid in the left-right direction.SOLUTION: A stand supporting an induction antenna comprises a stepladder 1 with four adjustable length legs 1b, a base plate 2 that is placed on and locked to a top plate 1a or step 1c of the stepladder 1, and a movable platform 3 that is placed on or fixed to the base plate. Locking end portions 4 that are bent downward and have a U-shaped cross section are provided on both ends of the base plate 2. The movable platform 3 has a height-adjustable section on a base plate whose height can be freely adjusted. A horizontal adjustment rotation section that rotates horizontally is provided on the height-adjustable section, and a vertical adjustment rotation section is provided on the horizontal adjustment rotation section. A top plate 13 that secures an induction antenna B is provided on the vertical adjustment rotation section.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] This invention relates to a mount for an electromagnetic wave receiving antenna for controlling the direction of thrust in a small-diameter pipe jacking method underground, and a method for installing an induction antenna using said mount, and more particularly to a stepladder-type induction antenna mount that can be attached to a commercially available stepladder to easily adjust the position of the receiving antenna, and a method for installing an induction antenna using said mount. [Background technology]

[0002] As shown in Figures 11 and 12, horizontal position measurement for directional control of the thrust head in the small-diameter pipe jacking method utilizes the principle of electromagnetic induction, where electromagnetic waves from a transmitter inside the thrust head are received by two coils on the left and right of an induction antenna installed perpendicular to the ground thrust baseline (thrust planning line), and which side of the two coils the transmitter (thrust head) is on is estimated from the strength of the electromagnetic waves, and the thrust direction of the thrust head is corrected accordingly. Therefore, the orientation of the induction antenna relative to the thrust baseline is extremely important, and accurate measurements cannot be made if the direction of travel of the thrust head deviates from the two coils.

[0003] As such, the installation location of the induction antenna is important in the small-diameter pipe jacking method, but until now, since it had to be installed on stable ground, a tripod for a camera or video camera was used instead of a dedicated mount. When installing in a stable ground, no major problems have occurred up until now, but when the induction antenna needs to be tilted forward and downward, care must be taken to prevent it from tipping forward.

[0004] Meanwhile, in the construction of electric power and communication pipes within the premises of electric power consumers as part of the pole-free construction project, construction work is increasingly being carried out in narrow, unstable areas within the ground of electric power consumers' homes. In narrow, unstable areas, it is difficult to horizontally install an induction antenna with a width of approximately 1m and a weight of approximately 10kg using a conventional tripod, and installation takes more time than ever before. In addition, in the narrow areas mentioned above, there is insufficient working space, and there are cases where workers have to work in an unstable position. Therefore, there is a need to shorten the installation time of induction antennas to reduce the burden on workers.

[0005] Patent Document 1 shows an example in which an induction antenna is supported by a tripod. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-124922 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0007] The drawback of supporting induction antennas with conventional tripods is that it takes a lot of time and effort to set up the antenna when the ground is not level and unstable, or when the location is narrow. In addition, the antenna is often tilted forward to capture the electromagnetic waves emitted from the underground propulsion head, and if the antenna is installed on a sloped ground, there is a risk that the entire tripod will fall over if the antenna is tilted forward.

[0008] In order to solve the above-mentioned problems, the present invention aims to provide a stepladder-type induction antenna stand that can be stably and firmly installed even on uneven ground using a commercially available stepladder, and that is made up of a jig that allows the angle of the induction antenna to be adjusted in the forward and backward directions, the height position to be adjusted up and down, and the induction antenna to be slidable in the left and right directions, and a method for installing an induction antenna using said stand. [Means for solving the problem]

[0009] The invention of claim 1 is a stepladder-type induction antenna stand, which is a stand for supporting an induction antenna and comprises a stepladder with four adjustable leg lengths, a base plate that is placed on and locked to the top plate or step of the stepladder, and a movable platform that is placed on or fixed to the base plate, and both ends of the base plate are provided with locking ends that are bent downward and have a U-shaped cross section, and the movable platform has a height-adjustable part on a base plate that can be freely adjusted in height, and a horizontal adjustment rotation part that rotates horizontally is provided on the height-adjustable part, and a vertical adjustment rotation part is provided on the horizontal adjustment rotation part, and a top plate that fixes the induction antenna is provided on the vertical adjustment rotation part.

[0010] Furthermore, the invention of claim 2 is a stepladder-type induction antenna stand according to claim 1, in which the height variable part of the movable platform is a table lift, the horizontal adjustment rotation part rotatably places the horizontal plate on a protruding shaft protruding from the upper surface of a base fixed to the upper plate of the table lift through a hole in the horizontal plate, and the vertical adjustment rotation part overlaps a hanging plate hanging from a top plate fixing the induction antenna on a vertical plate provided on the horizontal plate, and is rotatably joined by a horizontal shaft passing through the overlapping part, making the inclination of the top plate adjustable.

[0011] The invention of claim 3 is the stepladder-type induction antenna stand of claim 1, wherein the width of the locking end of the base plate is smaller than the width of the top board and the width of the step of the stepladder.

[0012] The invention of claim 4 is a method for installing an induction antenna using the stepladder-type induction antenna stand of claim 1, which comprises placing the stepladder on the ground on the propulsion plan line, adjusting the length of each of the four legs of the stepladder to set the top plate of the stepladder horizontally, selecting either the top plate or a step of the stepladder and attaching the base plate to it by fitting one locking end of the base plate into one edge of the top plate or the step, placing and fixing the movable base on the base plate, attaching the induction antenna to the top plate of the movable base, and adjusting the height, horizontal direction and vertical direction of the induction antenna using the height variable unit, horizontal direction adjustment rotation unit and vertical direction adjustment rotation unit of the movable base. [Effects of the Invention]

[0013] According to the invention of claim 1, the stepladder-type induction antenna stand of the invention is divided into a stepladder, a base plate, and a movable base. By securely attaching and adjusting each component, workers can easily and quickly install the stepladder-type induction antenna stand on the planned line. Therefore, even in a narrow installation location, the work can be done quickly and does not place an unnecessary burden on the workers. Furthermore, even if the installation ground is sloping and the induction antenna needs to be tilted forward, the stepladder itself is erected on the ground with four legs, so the center of gravity can be contained within the stepladder, allowing for stable installation.

[0014] Furthermore, since the base plate can be attached and installed on either the top plate or the step of a stepladder, the height of the induction antenna placed on the stand can be changed significantly.Furthermore, the height of the induction antenna can be fine-tuned using the height-adjusting part of the movable base.Therefore, even if the installation location of the induction antenna is changed during the pipe excavation work, the height of the transmitter in the underground excavation head and the induction antenna can be kept constant, ensuring the accuracy of electromagnetic wave measurement.

[0015] Furthermore, according to the invention of claim 2, the configuration of the movable base allows more reliable height adjustment, horizontal adjustment and vertical adjustment.

[0016] Furthermore, according to the invention of claim 3, the width of the engaging end of the base plate is smaller than the width of the top plate and the width of the step of the stepladder, so even if the stepladder-type induction antenna stand deviates from the propulsion plan line after installation, the base plate can be easily moved left and right to make fine adjustments.

[0017] Furthermore, according to the invention of claim 4, the stepladder is placed on the ground and the top of the stepladder is made horizontal, then the base plate and movable platform are installed in sequence, and finally the height, direction and angle of the movable platform can be adjusted, so that the induction antenna can be installed accurately and quickly along the planned line of advancement. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a perspective view of a stepladder of a stepladder-type induction antenna mount according to a first embodiment of the present invention. FIG. [Figure 2] 1 is a perspective view of a base plate of a ladder-type induction antenna stand according to a first embodiment of the present invention. FIG. [Figure 3] 1 is a front view of a movable base of a stepladder-type induction antenna mount according to a first embodiment of the present invention. FIG. [Figure 4] 1 is a side view of a movable base of a ladder-type induction antenna mount according to a first embodiment of the present invention. [Figure 5] 1 is a side view of a stepladder-type induction antenna stand according to a first embodiment of the present invention, with the base plate attached to the top plate of the stepladder. FIG. [Figure 6] 1 is a front view of a stepladder-type induction antenna stand according to a first embodiment of the present invention, with the base plate attached to the top plate of the stepladder. FIG. [Figure 7] 1 is a side view of a stepladder-type induction antenna stand according to a first embodiment of the present invention, with a base plate attached to a step of the stepladder. FIG. [Figure 8] 1 is a front view of a stepladder-type induction antenna stand according to a first embodiment of the present invention, with a base plate attached to a step of the stepladder. FIG. [Figure 9] 1 is a front view of a stepladder-type induction antenna stand according to a first embodiment of the present invention, with the base plate attached to the top plate of the stepladder and the induction antenna attached to the movable base. FIG. [Figure 10] FIG. 1 is a front view showing an example of use in which the configuration and layout of the induction antenna attached to the ladder-type induction antenna stand according to the first embodiment of the present invention is changed to keep the height of the measurement coil constant. [Figure 11] FIG. 1 is a longitudinal cross-sectional image diagram showing a method for controlling the thrust direction in a conventional small-diameter jacking method. [Figure 12] This is an image diagram of the position measurement of the thrust head in the thrust direction control method in the small diameter thrusting method that has been used conventionally. DETAILED DESCRIPTION OF THE INVENTION

[0019] (Embodiment Example 1) First Embodiment A stepladder-type induction antenna stand A according to a first embodiment of the present invention will be described with reference to FIGS.

[0020] The stepladder-type induction antenna stand A is composed of a stepladder 1, a base plate 2, and a movable base 3. The stepladder 1 is a commercially available product, and as shown in Figure 1, it can be folded into two parts, with four legs 1b extending from underneath two top plates 1a, and each leg 1b has an adjustable length. In addition, a step 1c is provided to connect each pair of legs 1b.

[0021] As shown in Fig. 2, the base plate 2 has locking ends 4 bent downward at both ends with a U-shaped cross section, and the locking ends 4 are configured to fit over the edge of the top plate 1a or step 1c of the stepladder 1. The width of the locking ends of the base plate 2 is smaller than the width of the top plate 1a of the stepladder 1 and the width of the step 1c.

[0022] 3 and 4, the movable base 3 has a table lift 6, which is a height-adjustable part, provided on a base plate 5, and the height of an upper plate 7 can be freely adjusted by turning a knob 6a provided on the side of the table lift 6. In addition, two height-adjustable legs 8 are provided on the front of the base plate 5 and one on the rear, and the base plate 5 can be supported horizontally by turning nuts 8a of these height-adjustable legs 8. Note that the height-adjustable legs 8 may not be provided, and in that case, the base plate 5 is fixed to the base plate 2 with screws.

[0023] The horizontal adjustment rotation unit has a protruding shaft 10 that protrudes vertically from the upper surface of a base 9 fixed to the upper plate 7 of the table lift 6, and the protruding shaft 10 passes through a hole 11a in a horizontal plate 11, which is then placed on the base 9 and a nut is screwed onto the protruding shaft 10, so that the horizontal plate 11 can be rotated horizontally and fixed freely. The vertical adjustment rotation unit also has a vertical plate 12 attached to the edge of the horizontal plate 11, and a hanging plate 14 hanging down from a top plate 13 to which the induction antenna B is fixed is placed over the vertical plate 12, with a horizontal shaft 15 passing through the overlapping portion and a nut screwed onto the horizontal shaft 15, so that the hanging plate 14 can be rotated vertically relative to the vertical plate 12 and overlapped so as to be fixed freely, and the tilt of the top plate 13 can be adjusted freely.

[0024] The stepladder-type induction antenna stand A has the above-mentioned configuration, and to install the induction antenna B using the stepladder-type induction antenna stand A, the stepladder 1 is placed on the ground on the planned propulsion line, the length of each of the four legs 1b of the stepladder 1 is adjusted, and the top plate 1a of the stepladder 1 is set horizontally using a spirit level or the like, and either the top plate 1a or the step 1c of the stepladder 1 is selected, and the base plate 2 is engaged by fitting one engaging end 4 of the base plate 2 into the edge of one of the top plate 1a or the step 1c.

[0025] 5 and 6 show the base plate 2 attached to the top plate 1a of the stepladder 1. Also, Figs. 7 and 8 show the base plate 2 attached to the step 1c of the stepladder 1. Then, the movable table 3 is placed on or fixed to the base plate 2. The movable table 3 may be placed on either side of the base plate 2, and may be placed on or fixed to almost the top of the stepladder 1 as in Figs. 5 and 6, or on the outside of the stepladder 1 as in Figs. 7 and 8.

[0026] When placing the movable table 3 on the base plate 2, the base plate 5 may be provided with adjustable legs 8 that can adjust the height, as shown in Figures 3 and 4. When fixing the movable table 3 to the base plate 2, holes may be drilled in advance so that the movable table 3 can be fixed with bolts and nuts.

[0027] After the movable table 3 is attached to the base plate 2, the induction antenna B is attached to the top plate 13 of the movable table 3. In this state, the height can be adjusted by turning the knob 6a of the table lift 6, which is the height-adjusting part of the movable table. Furthermore, the horizontal plate 11, which is the horizontal adjustment rotation part, is rotated around the protruding shaft 10 to determine the direction of the induction antenna B, and the nut on the protruding shaft 10 is tightened to fix the horizontal plate 11. Furthermore, the hanging plate 14, which is the vertical adjustment rotation part, is rotated around the horizontal shaft 15 to determine the tilt angle of the top plate 13 or the induction antenna B, and the nut on the horizontal shaft 15 is tightened.

[0028] These allow the height, horizontal direction and vertical direction of the induction antenna B to be adjusted.

[0029] Furthermore, as described above, the width of the base plate 2 is shorter than the width of the top plate 1a and step 1c of the stepladder 1, so that if the left-right position of the induction antenna B shifts, the base plate 2 can be shifted sideways.

[0030] Furthermore, in the case of small-diameter pipe jacking work, if the jacking length is long or the reach of the jacking pipe is located right next to a building, and the spacing between the measurement coils of induction antenna B changes during a single jacking, it is necessary to adjust the height of the measurement coil to be the same in the standard position where the measurement coil is extended horizontally and in the position where the measurement coil is bent and erected, as shown in Figure 10, in order to keep the height of the transmitter in the underground jacking head and the measurement coil of induction antenna B constant and ensure measurement accuracy. Therefore, the height of induction antenna B can be maintained by lowering base plate 2 from top plate 1a of stepladder A in Figure (a) to step 1c in Figure (b) and installing it, and then erecting the measurement coils on both sides of induction antenna B.

[0031] In the first embodiment, nuts are screwed onto the protruding shaft 10 and the horizontal shaft 15, and the horizontal plate 11 and the hanging plate 14 are fastened by tightening the nuts, but these nuts may be wing nuts. Also, in the first embodiment, a stepladder 1 having one step 1c is used, but the stepladder 1 may also have multiple steps 1c. [Explanation of symbols]

[0032] A. Stepladder-type induction antenna stand B. Induction antenna 1 Stepladder 1a Top board 1b Legs 1c Step 2 Base plate 3 Movable base 4 Locking end 5 Board 6 Table lift 6a Knob 7 Top plate 8 Adjustable legs 8a Nut 9 Base 10 Protruding shaft 11 Horizontal plate 11a hole 12 vertical plate 13 Top plate 14 Hanging plate 15 horizontal axis

Claims

1. In a mount supporting an induction antenna, A stepladder-type induction antenna stand, characterized in that it comprises a stepladder whose four legs can be adjusted in length, a base plate that is placed on and engaged with the top plate or step of the stepladder, and a movable platform that is placed on or fixed to the base plate, wherein both ends of the base plate are provided with engaging ends that are bent downward and have a U-shaped cross section, the movable platform has a height-adjustable part on a base plate whose height can be freely adjusted, a horizontal adjustment rotation part that rotates horizontally is provided on the height-adjustable part, and a vertical adjustment rotation part is provided on the horizontal adjustment rotation part, and a top plate that fixes the induction antenna is provided on the vertical adjustment rotation part.

2. 2. The stepladder-type induction antenna stand according to claim 1, wherein the height variable part of the movable platform is a table lift, the horizontal adjustment rotation part rotatably places the horizontal plate on a protruding shaft protruding from the upper surface of a base fixed to the upper plate of the table lift through a hole in the horizontal plate, and the vertical adjustment rotation part overlaps a hanging plate hanging from a top plate to fix the induction antenna on a vertical plate provided on the horizontal plate, and rotatably joins them with a horizontal shaft penetrating the overlapping part, making the inclination of the top plate adjustable.

3. 2. The ladder-type induction antenna stand according to claim 1, wherein the width of the engaging end of the base plate is smaller than the width of the top board and the width of the step of the ladder.

4. 2. The method for installing an induction antenna using a stepladder-type induction antenna stand according to claim 1, characterized in that: the stepladder is placed on the ground on the propulsion plan line, the lengths of the four legs of the stepladder are adjusted to set the top plate of the stepladder horizontally, the base plate is attached to either the top plate or a step by selecting the stepladder top plate or a step, one locking end of the base plate is fitted into one edge of the top plate or the step to lock it, the movable platform is placed on the base plate and fixed, the induction antenna is attached to the top plate of the movable platform, and in this state the height, horizontal direction and vertical direction of the induction antenna are adjusted using the height variable unit, horizontal direction adjustment rotation unit and vertical direction adjustment rotation unit of the movable platform.

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