JP4491636B2 - Pipe inner diameter measuring device - Google Patents

Description

  The present invention relates to a pipe inner diameter measuring apparatus, and more particularly to a pipe inner diameter measuring apparatus useful when applied to an existing pipe line having a small diameter (for example, a diameter of 400 mm or less).

  In existing pipes, for example, existing sewage pipes having a small diameter, the pipe inner diameter is unlikely to be constant over the entire length, and often changes in size. In addition, the rate of change of the inner diameter of the pipe line is often relatively large and may reach about 10% of the reference inner diameter at the maximum. Examples of changes in the inner diameter of the pipeline include, for example, a difference in inner diameter between a new pipe and an old pipe found in partial replacement work of pipes, pipe deformation caused by running of heavy vehicles (vibration and high load), etc. Can do. Thus, when refurbishing the inner surface of an existing pipe line, for example, when applying a method of attaching a liner to the inner surface of the pipe, such as a hose lining method, a liner of a size that roughly matches the inner diameter of the pipe before construction. It is desirable to measure the inner diameter of the pipe in order to select and record the effective cross-section and finished condition of the corrected existing pipe after construction.

  Conventionally, as a pipe inner diameter measuring apparatus, for example, in Japanese Patent Application Laid-Open No. 7-260411, after the amount of strain of a leaf spring contacting the inner surface of a tube is electrically detected once through a strain gauge installed on the leaf spring, There has been proposed a system that converts the static detection output into a displacement amount of the inner diameter of the pipe.

  However, the method of replacing the strain amount of the leaf spring with the electrical detection output once as in the conventional measuring apparatus is indirect, and such indirect measurement is not preferable in terms of measurement accuracy. In addition, as a general tendency, the strain of the leaf spring tends to vary as the amount of strain increases. Therefore, in a conventional measuring apparatus using the strain of the leaf spring, the measurement accuracy is improved in a region where the displacement of the tube inner diameter is small. Even if there is no particular problem, the measurement accuracy is not reliable in the region where the amount of change is large. Therefore, such a conventional apparatus is not applied to the measurement of the inner diameter of a pipe having a relatively large inner diameter change, such as an existing small-diameter sewer pipe.

  One object of the present invention is to directly measure a change (displacement) in the inner diameter of a pipe via a displacement meter, and to measure with high accuracy regardless of the magnitude of the displacement, particularly for an existing pipe with a relatively large inner diameter change. It is an object of the present invention to provide a pipe inner diameter measuring device useful for measuring the inner diameter of a pipe, for example, an existing water pipe having a small diameter.

  Still another object of the present invention is that in the case of a measuring device applied to a small-diameter pipe, the size of the device main body in the diameter direction is severely limited. An object of the present invention is to provide a pipe inner diameter measuring device capable of installing a differential transformation type displacement sensor, a magnetostrictive linear displacement sensor, a linear encoder, etc. without difficulty in designing the device. Other features of the present invention will become apparent from the following description.

Means for Solving the Invention

  The present invention is arranged at a plurality of locations around the main body, a main body installed on the central axis in the pipe to be measured, centering means for constantly holding the main body on the central axis in the pipe, and A plurality of contacts and a plurality of contacts on the main body are projected in the radial direction (tube diameter direction), and each of the contacts can be individually linearly moved in the tube diameter direction in this projecting state. Holding and pressing means that holds and presses each of the contacts individually against the spring against the spring at an arbitrary moving position, and the measuring unit is installed on the main body so as to be linearly movable in the tube axis direction. A plurality of displacement meters, and a movement transmitting means for linearly moving the measuring portion of the displacement meter in the tube axis direction by an amount corresponding to the linear movement amount in the tube diameter direction as the contact moves linearly in the tube diameter direction. It has According to the pipe inner diameter measuring apparatus according to claim.

  In a preferred embodiment of the present invention, the holding and pressing means comprises a link mechanism portion and a spring device that rises in the tube radial direction from above the main body portion, and the link mechanism portion has a short ring portion and twice the short ring portion. A long ring portion having a length, wherein the short ring portion is pivotally connected to the main body at the lower end portion and to the intermediate portion of the long link portion at the upper end portion, and the long link portion is connected to the main body via a slider at the lower end portion. The slider is movable in the tube axis direction on the main body, and the upper end of the long link portion is linearly movable in the tube radial direction as the slider moves in the tube axis direction. A contact is held at the upper end of the long ring portion, and the spring device is incorporated in the link mechanism so as to constantly urge the slider in the direction in which the long link portion stands up. It has a configuration which can be pressed against the inner surface of the contact via a more sliders and long link portion.

  In another preferred embodiment of the present invention, the movement transmission means includes a movement transmission line which changes the direction from the pipe radial direction to the pipe axial direction via a guide installed on the main body, and the pipe radial side of the line is in contact with the movement transmission means. The tube axis direction side is connected to the measuring unit of the displacement meter installed in the tube axis direction. In addition, the linear movement of the contact in the tube diameter direction is directly transmitted to the measuring unit of the displacement meter while changing the direction in the tube axis direction, and the measuring unit is linearly moved in the tube axis direction by an amount corresponding to the linear movement amount in the tube axis direction It can be moved. A piston cylinder device functioning as a spring device is installed between the end of the movement transmission line on the tube axis direction side and the measuring part of the displacement meter, and the piston rod of the device extends in the tube axis direction, and the rod One end side is connected to the transmission line and the other end side is connected to the measuring unit, and the measuring unit and the transmission line are urged toward the displacement meter by the action of a spring device of the piston cylinder device, and this urging force is pressed against the contactor. It is set to be overwhelmingly smaller than force.

The invention's effect

  According to the measuring apparatus of the present invention, as the inner diameter of the tube changes, the contact moves linearly in the tube radial direction by the amount of change. Since it is configured to move linearly in the axial direction, it is possible to directly measure the change in pipe inner diameter by applying a displacement meter, and to measure with high accuracy regardless of the amount of change in the pipe inner diameter. Is possible. Furthermore, in the case of small-diameter pipes, the size in the pipe diameter direction of the main body of the device is subject to severe restrictions, so installation of the displacement gauge in the pipe diameter direction is impossible due to device design. Since the configuration is such that the displacement meter is installed in the direction of the tube axis with respect to the section, the displacement meter can be installed in the main body of the apparatus without any unreasonable design, and a commercially available displacement meter can be applied without difficulty to measure the inner diameter of the tube.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a situation in which the apparatus of the present invention is installed in a pipe a to be measured. As is apparent from FIG. 1, the device of the present invention includes a main body portion 1 extending in the tube axis direction on the central axis of the tube a, and the main body portion 1 is placed on the main body portion 1 on the tube a. Centering means 2 for holding on the central axis is provided.

  As the centering means 2, a pantograph type is shown in FIG. 1, and the pantograph portion 3 has an isosceles triangle link structure, and is provided at three positions on the outer peripheral portion of the main body portion 1 at intervals of 120 ° (see FIG. 2). ), And a common slide ring 4 is provided at the lower end of one hypotenuse 3a of the panda graph section 3. The slide ring 4 can be reciprocated in the tube axis direction while being fitted on the main body 1, and the pantograph 3 is moved in the radial direction by the action of a spring device (not shown) installed on the main body 1. The roller portion 5 installed on the top of the panda graph portion 3 can be constantly pressed against the inner surface of the tube a regardless of the change in the inner diameter of the tube. As shown in FIG. 1, the centering means 2 is usually installed at two locations, the front portion and the rear portion of the main body portion 1. As the centering means 2, instead of the panda graph system shown in the figure, for example, centering means of various configurations applied to various known in-pipe construction machines can be applied.

  Further, on the main body 1, for example, a contact 6 for measuring a change in the inner diameter of the tube, and the contact 6 can be linearly moved in the tube radial direction so as to be positioned between the centering means 2 and 2. Holding and pressing means 7 that holds and presses the contact 6 against the inner surface of the tube a against the spring at an arbitrary moving position is independently provided at four positions at intervals of 90 °, for example, as shown in the cross-sectional view of FIG. The change of the inner diameter of the tube can be measured at four locations in the circumferential direction. The number of measurement points in the circumferential direction is not particularly limited, but about 3 to 8 points are appropriate for the design of the apparatus.

  As the holding and pressing means 7, FIG. 1 shows a case where the holding and pressing means 7 is constituted by a link mechanism portion 8 that stands up from the main body portion 1 in the tube diameter direction and a spring device 9 that is incorporated in the mechanism portion 8. The link mechanism portion 8 is composed of a short link 8a and a long link 8b whose length is twice that of the short ring portion 8a. The short link 8a has a link length of the long link 8b at the upper end portion on the main body portion 1 at the lower end portion. Each long link 8b is pivotally connected to the middle point on the main body 1 via a slider 10 that can move in the tube axis direction on the main body 1 at the lower end. The pivot connecting portions at the lower ends of the short and long links 8a and 8b are located on the same straight line extending in the tube axis direction. The upper half portion of the long link 8b extends upward beyond the pivot connection portion with the short link 8a, and terminates immediately above the tube diameter direction of the pivot connection portion at the lower end portion of the short link 8a.

  The link mechanism portion 8 having the above-described configuration includes a one isosceles triangle including the bottom half between the pivot connecting portions at the lower ends of the short and long links 8a and 8b and the lower half of the short link 8a and the long link 8b as a hypotenuse. The other isosceles triangle T2 with T1 and the bottom end between the lower end of the short link 8a and the upper end of the long link 8b and the other half isosceles triangle T2 with the upper half of the short link 8a and the long link 8b as the hypotenuse is adjacent. Are formed together. Thus, when the lower end of the long link 8b is linearly moved along the base of the one isosceles triangle (in the tube axis direction) via the slider 10, the upper end of the long link 8b becomes the other isosceles triangle. It will move linearly along the bottom (tube diameter direction). Therefore, by holding the contact 6 at the upper end of the long link 8b that takes such an operation, the diameter of the contact 6 is increased as the contact 6 is moved in the tube axis direction of the slider 10 and thus the lower end pivot connecting portion of the long link 8b. Can be moved linearly.

  In order to always press the contact 6 against the inner surface of the pipe, the pivot 10 at the lower end of the slider 10 and the long link 8b is connected to the pivot at the lower end of the short link 8a by a spring device 9 installed on the main body 1. It is energized towards. By this urging, the contact 6 held at the upper end of the long link 8b is forcibly pressed against the inner surface of the pipe. With the above configuration, the contact 6 can be held in the main body 1 so as to be linearly movable in the tube radial direction and to be pressed against the inner surface of the tube. As the contactor 6, a roller type as shown in the figure is suitable, but is not necessarily limited to such a configuration.

  Furthermore, on the main body 1, displacement gauges 11 that can directly measure changes in the inner diameter of the tube are installed for each contact 6 independently at four locations (see FIG. 3) in the illustrated embodiment. Such a direct measurement type displacement meter 11 is already commercially available in various configurations and can be obtained as a commercial product. In an apparatus applied to the measurement of the inner diameter of a small-diameter pipe, the dimension in the pipe diameter direction of the main body 1 is considerably severely limited, but the dimension in the pipe axis direction is not substantially limited. On the other hand, the displacement meter 11 is generally long in size. In the present invention, the displacement meter 11 is installed on the main body 1 in parallel to the tube axis direction, that is, the central axis so that there is no difficulty in designing the apparatus.

  Further, a movement transmission for transmitting the linear movement of the contact 6 in the pipe radial direction according to the change in the pipe inner diameter to the measuring section 12 of the displacement meter 11 on the main body 1 without changing the moving amount. Means 13 are provided. The illustrated movement transmission means 13 is provided with a transmission wire 15 whose direction is changed in the tube radial direction and tube axis direction by a guide roller 14, and the wire 15 connects the contact 6 and the measuring unit 12 of the displacement meter 11. is doing. The straight line portion 15a in the tube diameter direction of the filament 15 is extended in a direction orthogonal to the central axis of the main body portion 1, and the straight line portion 15b in the axial direction is parallel to the central axis line of the main body portion 1. The linear movement of the child 6 in the tube diameter direction can be transmitted to the measuring unit 12 of the displacement meter 11 without changing the moving amount, and the change in the tube inner diameter can be directly measured by the displacement meter 11.

  The commercially available displacement meter 11 includes a type that is biased so that the measuring unit 12 can automatically return and a non-biased type that cannot automatically return. When the contact 6 moves linearly in the direction of expansion of the inner diameter of the pipe, the measuring unit 12 is forcibly pulled out from the displacement meter 11 by the biasing force (pressing pressure) loaded on the contact 6, so that the measuring unit 12 There is no particular problem with either the energized type or the non-energized type. However, when the contact 6 moves in the direction of reducing the inner diameter of the tube, the presence or absence of energization is a problem. The linear movement of the contact 6 in the direction of reducing the inner diameter of the tube cannot be transmitted to the measuring unit 12. Thus, when the non-biasing type displacement meter 11 is applied, it is necessary to apply the urging means.

  FIG. 1 shows an example of the urging means, and a piston cylinder device 16 that can function as a spring device is applied. The piston cylinder device 16 is installed so as to form a line between the measuring unit 12 and the axial linear portion 15b of the transmission line 15, and the cylinder 16a is fixed to the main body 1 side. On the other hand, one end of the piston rod 16b is connected to the linear portion 15b in the axial direction, and the other end is connected to the measuring portion 12. Of the cylinder chambers 16a1 and 16a2 partitioned by the piston 16c, pressurized gas (for example, air) is supplied into one cylinder chamber 16a1 located on the linear portion 15b side, and the other cylinder chamber 16a2 on the measurement portion 12 side is air. Has been released. Thus, the pressure difference generated between the two cylinder chambers 16a1 and 16a2 acts on the measurement unit 12 via the piston 16c, and urges the measurement unit 12 in the return direction. The urging pressure applied to the measuring unit 12 is set to be much smaller than the urging pressure applied to the contact 6, and the urging to the measuring unit is not performed for linear movement of the contact 6 or for pressing the inner surface of the tube. There is no adverse effect. Such an urging means can also be applied to a displacement meter 11A having an automatic return function such as a wire encoder type as shown in FIG.

  The inside of the existing pipe is an environment where water, dust, etc. are present, and this has an adverse effect on the displacement meter, which is a precision electric device, so that it is preferably housed in the sealed container 17, but the piston cylinder device is applied. By doing so, the measuring part 12 of the displacement meter can be shut off from the outside.

  When applying the same function as the piston cylinder device 16 described above as the biasing means for the pantograph and the link mechanism (contactor 6), the pressure in the cylinder chamber is released, as shown in FIG. The pantograph section 3 and the link mechanism section 8 can be folded on the main body section 1 and become small, which is convenient for apparatus recovery from the inside of the pipeline, transportation of the apparatus, and storage.

  Hereinafter, based on FIG. 1, the measurement situation of the inner diameter change of the tube will be described. The apparatus of the present invention is moved in the direction of the pipe axis in the pipe a to be measured under the application of traction means (not shown) such as a traction rope in the pipe installation state shown in FIG. Measure the change in tube inner diameter. For example, when the pipe inner diameter changes in the diameter expansion direction with reference to FIG. 1, the contact 6 linearly moves in the pipe diameter direction and in the diameter expansion direction by the amount corresponding to the diameter expansion. 13 is transmitted to the measuring unit 12 of the displacement meter 11 and is linearly moved forward by the same amount as the linear movement in the direction of the tube axis and forward. Can be measured.

Further, for example, when the pipe inner diameter changes in the diameter reduction direction with reference to FIG. 1, the contact 6 linearly moves in the pipe diameter direction and in the diameter reduction direction, and this linear movement is displaced via the movement transmitting means 13. It is transmitted to the measuring unit 12 of the total 11, and the measuring unit 12 is linearly moved backward in the tube axis direction by the linear movement amount of the contact 6, and the reduction change amount of the pipe inner diameter can be measured by the linear movement of the measuring unit 12.
Incidentally, the linear movement of the measurement unit 12 in the axial direction rearward is an automatic return function (type of FIG. 5) provided in advance in the measurement unit 12 and / or an attachment interposed between the measurement unit 12 and the movement transmission means 13. This is performed by the action of a piston cylinder device 16 (FIG. 1 type) as a biasing means.

  According to the apparatus of the present invention, as the tube inner diameter changes, the contact moves linearly in the tube radial direction by the amount of change, and as the contact moves linearly in the tube diameter direction, the measuring unit of the displacement meter moves the tube Since it is configured to move linearly in the direction, it is possible to directly measure the change in the inner diameter of the pipe by applying a displacement meter, and it is possible to measure with high accuracy regardless of the amount of change in the inner diameter of the pipe. it can. Furthermore, in the case of small-diameter pipes, the size of the main body of the device is subject to severe restrictions, so installation of the displacement meter in the pipe diameter direction is impossible due to device design. Since it is configured to be installed in the tube axis direction with respect to the section, there is no unreasonableness in designing the device, and a commercially available displacement meter can be applied without difficulty to measure such a tube inner diameter.

It is a longitudinal cross-sectional view which shows one Embodiment of this invention, and the installation condition in a pipe | tube. It is a cross-sectional view showing the installation state of the centering means. It is a cross-sectional view which shows the installation condition of a contactor and a holding | maintenance pressing means. It is a longitudinal cross-sectional view which shows this invention apparatus in a diameter-reduced state. It is a longitudinal cross-sectional view which shows other implementation of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main-body part 2 Centering means 3 Pantograph part 3a One hypotenuse side of a pantograph part 4 Slide ring 5 Roller part 6 Contact 7 Holding pressing means 8 Link mechanism part 8a Short link 8b Long link 9 Spring apparatus 10 Slider 11 Displacement meter 12 Displacement meter Measuring unit 13 Movement transmission means 14 Guide roller 15 Transmission line 15a Pipe radial direction straight part 15b Pipe axis direction straight part 16 Piston cylinder device 16a Cylinder 16a1 One cylinder chamber 16a2 Other cylinder chamber 16b Piston rod 16c Piston 17 Sealed container

Claims (3)

A main body installed on the central axis in the pipe to be measured, centering means for constantly holding the main body on the central axis in the pipe, and a plurality of contacts arranged at a plurality of locations around the main body And projecting radially from the plurality of locations on the main body part in the radial direction (tube diameter direction), and in this projecting state, each of the contacts is individually held so as to be linearly movable in the tube diameter direction and arbitrarily Holding and pressing means that individually presses each of the contacts against the spring against the inner surface of the tube at a moving position, and a plurality of units installed on the main body so that the measuring unit can move linearly in the tube axis direction. Displacement meter, and movement transmission means for linearly moving the measuring part of the displacement meter in the tube axis direction by an amount corresponding to the linear movement amount in the tube diameter direction as the contact moves linearly in the tube diameter direction. With features That the tube internal diameter measurement device The holding and pressing means includes a link mechanism portion that stands up from the main body portion in the tube radial direction and a spring device that is incorporated in the mechanism portion. The link mechanism portion includes a short link and a long link that is twice as long as the short ring portion. The short link is pivotally connected to the middle of the link length of the long link at the upper end of the short link at the lower end, respectively, while the long link is on the main body at the lower end of the main link. It is pivotally connected via a slider that can move in the tube axis direction, and the upper end of the long link extends upward beyond the pivotal connection with the short link, and the radial direction of the pivotal connection at the lower end of the short link The upper end of the long link holds the contact and can move linearly in the tube radial direction by moving the slider in the tube axis direction. The slider is biased by a spring device. The above contact Child Any inner tube diameter measuring apparatus according to claim 1, wherein it is in the configuration that can be pressed against the inner surface at the linear movement position. The movement transmission means includes a transmission wire whose direction is changed in the tube radial direction and the tube axis direction by a guide roller, the wire connecting the contact and the measuring unit of the displacement meter, and the tube diameter of the wire The linear part of the direction is extended in a direction perpendicular to the central axis of the main body part, the linear part of the axial direction is parallel to the central axis of the main body part, and the measuring part has an urging force smaller than the in-tube pressing pressure of the contact. The pipe inner diameter measuring device according to claim 1 or 2, further comprising an automatic return function.

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