JP7765809B2 - Recovery device - Google Patents

Description

The present invention relates to a recovery device that is inserted through a thin tube attached to a pipe through which a liquid flows, and that recovers objects that flow inside the pipe along with the liquid.

Underground pipelines carry pressurized water, including municipal water, industrial water, and agricultural water. These pipelines are constantly subjected to forces caused by vibrations from vehicles traveling on the road, forces associated with land subsidence, and forces acting in the direction of the pipeline and/or in directions intersecting the pipeline's direction during earthquakes. This can cause gaps to appear at the pipe joints or cracks to form in the pipe walls, leading to the risk of the water leaking underground. For example, in the case of industrial or agricultural water, treating this water is costly, and leakage results in waste.

For this reason, underground pipelines are inspected for leaks and their locations. To conduct such inspections, a method has been proposed in which a spherical moving object is moved inside a pipeline through which water flows, and the sounds generated within the pipeline during the movement are collected and recorded, while the moving position is detected, thereby detecting the presence and location of leaks in the pipeline (see, for example, Patent Document 1). In this detection method, for example, a spherical moving object is inserted into the main pipe from a valve located upstream of a waterworks pipeline through which pressurized water flows. The spherical moving object is then captured and recovered by a collection member inserted into the main pipe from a valve located downstream.

Patent Document 2 proposes a collection member for collecting spherical moving objects moving inside a main pipe. This collection member is constructed by pivotally connecting the upper and lower ends of a pair of flexible and elastic frame members. The pivotable support member connected to the lower ends is then moved closer or farther away from the support member connected to the upper ends, bringing the pair of frame members closer together to reduce their diameter so that they can pass through the valve plug, or moving them apart to form a roughly circular shape that can fit around the inner circumference of the main pipe. This makes it possible to collect spherical moving objects moving inside the main pipe, and to collect the collected moving objects through the valve plug.

The spherical moving body described above rolls along the bottom of the main pipe, which poses the problem that the sound generated when it rolls against the bottom is recorded as noise, making it necessary to separate this from the sound generated by the leak. For this reason, a leak detection device has been proposed in which the moving body has approximately the same specific gravity as the liquid flowing through the pipe, preventing the moving body from colliding with the pipe wall and generating sound (see, for example, Patent Document 3). The moving body described in Patent Document 3 is formed into a capsule shape by attaching hemispherical caps to both ends of a cylindrical body.

Furthermore, to more accurately detect the location of a leak in a pipeline, a detection method and device have been proposed in which multiple sound collection elements with mutually opposing directivity are placed inside a moving object, and sound data collected by these sound collection elements can be compared and examined (see, for example, Patent Documents 4 and 5).

Japanese Patent No. 5583994 (JP 2011-196745 A) JP 2017-198296 A Japanese Patent Application Laid-Open No. 2018-189411 JP 2019-152450 A Japanese Patent Application Laid-Open No. 2021-021665

The moving bodies that make up the detection devices described in Patent Documents 3 to 5 are formed in a long, thin cylindrical shape, and their length is greater than the diameter of the valve plug portion used to collect the fluid from the main pipe. Furthermore, the collection member described in Patent Document 2 does not have a shape that can capture cylindrical moving bodies, as the moving bodies to be collected are spherical.

For this reason, when attempting to capture the moving bodies described in Patent Documents 3 to 5 using the collection member described in Patent Document 2, a problem arises in that when the tip of the moving body comes into contact with the net, it rotates across the pipeline (the moving body intersects with the axis of the pipeline). In this case, because the longitudinal dimension of the moving body is larger than the diameter of the valve plug, when attempting to pull the collection member out of the valve plug, the rotated moving body interferes with the connection between the valve plug and the main pipe, preventing it from passing through the valve plug.

The object of the present invention is to provide a collection device that can capture cylindrical detection devices while maintaining their longitudinal direction parallel to the axial direction of the piping, and can reliably pass them through thin pipes for collection.

To solve the above-mentioned problems, a representative recovery device according to the present invention is a recovery device for recovering a cylindrical detection device that is inserted through a tube that is attached to a pipe through which a liquid flows and is thinner than the pipe, and flows through the inside of the pipe together with the liquid to detect liquid leaks. The recovery device comprises a frame member made of a flexible and elastic frame material, which, when expanded, has a substantially circular shape with a diameter slightly smaller than the inner diameter of the pipe through which the liquid flows, and, when contracted, is thinner than the inner diameter of the thin tube attached to the pipe; and a frame member attached to an end of the frame member, which is inserted through the thin tube into the pipe. The collection member comprises a support member attached to the frame member, one end of which is connected to the frame material that makes up the frame member, a guide section that is formed so that when the frame member is expanded, it has a generally circular shape with a diameter slightly smaller than the inner diameter of the piping and a diameter that decreases toward the other end, and is longer than the length when the frame member is contracted, and a storage section that is connected to the other end of the guide section, has a closed tip, is cylindrical, has a length longer than the length of the detection device, and a diameter shorter than the length of the detection device and larger than the outer diameter of the detection device.

In the recovery device of the present invention, when a detection device that has traveled through the pipe together with the liquid is captured by a capture member attached to a frame member, the longitudinal direction of the captured detection device can be held parallel to the axis of the pipe. Furthermore, when the captured detection device is passed through a thin pipe, the detection device does not interfere with the connection between the thin pipe and the pipe, allowing for smooth recovery.

In other words, the collection member attached to the frame member has a guide section and a storage section that is continuous with the guide section. This storage section is longer than the length of the detection device to be collected, but shorter than the length and larger than the outer diameter of the detection device. Therefore, when the detection device is stored in the storage section, its longitudinal direction can be kept parallel to the axial direction of the piping.

In particular, because the guide section is positioned between the frame member and the storage section, the detection device that moves inside the piping along with the liquid can be guided by the guide section and move to the storage section. Furthermore, because the guide section is formed to be longer than the length of the frame member when it is narrowed, when the recovery device is removed from the piping through a thin tube, the detection device stored in the storage section can be held in a position where its end does not interfere with the frame material of the narrowed frame member. Therefore, the detection device stored in the storage section can be smoothly removed by passing through the thin tube without interfering with the connection between the thin tube and the piping.

10A and 10B are a front view and a side view of the recovery device in a state where the frame member is folded and lifted up after collecting the detection device. 1A and 1B are a front view and a side view of the recovery device with the frame member open. FIG. 2 is a diagram illustrating the configuration of a collection member. 10A and 10B are diagrams illustrating another example of the collection member. FIG. 10 is a diagram illustrating a state in which a detection device is collected inside a pipe through which a liquid flows. 10 is a diagram illustrating the state when the detection element is collected and then recovered through a thin tube. FIG. FIG. 1 is a diagram illustrating a method for detecting a leak in a main pipe.

The configuration of the recovery device according to the present invention will be described below. The recovery device according to the present invention is a device for recovering cylindrical detection devices that move with the liquid flowing inside a pipe (hereinafter referred to as the "main pipe") and are configured to collect and record sound during this movement. The recovery device is inserted into the main pipe through a thin tube (e.g., a valve plug portion, hereinafter referred to as the "rise pipe") attached to the main pipe, and is configured to capture the detection devices that have moved inside the main pipe, and then recover them to the outside through the riser pipe.

In this invention, the liquid flowing inside the main pipe may be any liquid that flows under pressure, such as drinking water, agricultural water, or industrial water. However, it is not limited to such liquids, and can also be applied to oil-based liquids.

Prior to explaining the recovery device A of this embodiment, we will briefly explain, with reference to Figure 7, the procedure for detecting a leak 43 using a detection device 45 inserted inside the main pipe 41. The main pipe 41 is equipped with multiple riser pipes 42 that are thinner than the main pipe 41. The main pipe 41 carries the target liquid and is set to an optimal diameter depending on conditions such as the liquid and its intended use. Furthermore, the riser pipes 42 are fitted with valves for discharging the liquid or air flowing inside the main pipe 41, and typically have a diameter of approximately 75 mm.

Detection device 45 is cylindrical with hemispherical lids on both ends. It is inserted into main pipe 41 from the upstream riser pipe 42 and moves downstream along with the liquid flowing through main pipe 41. Inside detection device 45 are a microphone that collects sound transmitted through the liquid, a recording device that records the collected sound, an accelerometer and gyro that record the movement of detection device 45, and a clock that records the time the data obtained by these components is recorded.

Because the detection device 45 houses the various equipment described above, its overall length is greater than the diameter of the riser pipe 42. Furthermore, the volume, weight, etc. of the detection device 45 are adjusted so that its specific gravity is equal to that of the liquid flowing inside the main pipe 41.

After starting leak detection for the target pipe 41, recovery device A, described below, is inserted into the pipe 41 through a preset riser 42 in the pipe 41. The detection device 45 then travels with the liquid until it reaches recovery device A, where it is passed through the riser 42 and recovered from the main pipe 41. After recovering the detection device 45, the presence and location of a leak 43 in the main pipe 41 can be detected by extracting data such as the recorded sound, the time the sound occurred, and accelerometer data.

The recovery device A according to this embodiment will now be described. The recovery device A is configured with a frame member 10 consisting of a pair of frame members 11, a support member 20 that attaches the frame member 10 to its lower end 20a, and a collection member 30 that has a storage section 31 and a guide section 32 and is attached to the frame member 10.

The frame member 10 is attached to the support member 20 and also has the collection member 30 attached to it, and comprises a pair of flexible and elastic frame members 11. One end (upper end) of each of the pair of frame members 11 is attached to a pivot piece 21 that is configured to pivot at a slight incline relative to the lower end 20a of the support member 20. Therefore, each frame member 11 is pivotally attached to the support member 20. The other end (lower end) of each of the pair of frame members 11 is attached to a hinge 12.

The frame member 10 is slightly curved in the direction of expanding in diameter when free, with the upper end of the frame material 11 attached to the pivot piece 21 and the lower end attached to the hinge 12. The diameter expands when a force is applied in a direction that moves the lower end, the hinge 12, closer to the lower end 20a of the support member 20. Therefore, by adjusting the length of the frame material 11 to correspond to the diameter of the main pipe 41 for which the recovery device A is to be used (approximately half the circumferential length), the frame member 10 can be positioned opposite the inner surface of the main pipe 41 and expanded in diameter in a circular shape. The diameter of the frame member 10 when expanded in a circular shape is not limited and can be set appropriately between 200 mm and 1200 mm to correspond to the inner diameter of the main pipe 41.

There are no particular restrictions on the material or structure of the frame material 11 that makes up the frame member 10, and any material that is flexible and elastic and does not adversely affect the target liquid can be used. Such materials include metals such as stainless steel and spring steel, and synthetic resins. Shapes include plate material and rod material. In particular, when using rod material, it does not have to be a single piece; multiple pieces can be lined up in the direction of liquid flow.

The material and shape used for the frame material 11 should preferably be selected taking into consideration the structure when attaching the capture member 30, which will be described later.

The support member 20 is formed in the shape of a pipe with a preset diameter and length. There are no particular limitations on the length of the pipe used as the support member 20, and it is preferable to set it to a value that takes operability into consideration. Furthermore, if the riser pipe 42 is long, it is preferable to configure it so that a unit-length extension pipe 25 can be added to the upper end 20b.

The guide member 22 located at the lower end 20a of the support member 20 guides the frame member 10 so that it does not get caught on the joint between the main pipe 41 and the riser pipe 42 when the frame member 10 and the capture member 30 are pulled out of the main pipe 41 after the detection device 45 has been captured by the capture member 30. For this reason, the guide member 22 has a tapered guide piece 22a whose dimensions correspond to the diameter of the riser pipe 42.

An underwater camera 23 that monitors the capture member 30 is attached to the lower end of the guide member 22, and the image captured by this underwater camera 23 is transmitted via cable 23a to a monitor installed in a control unit (not shown) located on land, and is also recorded. Reference numeral 23b denotes a protective cover for the underwater camera 23. By positioning the underwater camera 23 in this way, it is possible to monitor the behavior of the capture member 30 inserted inside the main pipe 41, and to confirm whether the detection device 45 has been captured by the capture member 30.

The flow of liquid acts on the frame member 10 and collection member 30 inserted inside the main pipe 41 in a downstream direction, and this force is received by the frame member 10. For this reason, it is preferable to insert a rod-shaped reinforcing member 24 inside the support member 20 so that its lower end can abut against the hinge 12 located at the lower end of the frame member 20. This configuration makes it possible to withstand the load caused by the flowing liquid that occurs when the frame member 10, to which the collection member 30 is attached, expands in diameter inside the main pipe 41.

The capture member 30 is attached to the frame member 10 and captures the detection device 45 moving inside the pipe 41. The capture member 30 is composed of a storage section 31 that stores the detection device 45, and a guide section 32 that has one end connected to the storage section 31 and the other end connected to the frame material 11 of the frame member 10. The overall length of the capture member 30, consisting of the storage section 31 and the guide section 32, is not particularly limited, but it is preferably set to a range of two to three times the inner diameter of the target main pipe 41.

The storage section 31 has a length longer than the length of the detection device 45, and a diameter shorter than the length of the detection device 45 and larger than the outer diameter. Therefore, when the detection device 45 moving with the liquid inside the main pipe 41 is collected, it can be stored in a state roughly parallel to the axis of the pipe 41. There are no limitations on the shape of the storage section 31. However, within the above-mentioned dimensional range, it is preferable that it be roughly cylindrical or have a small tapered angle.

The guide section 32 is tapered, with its diameter decreasing from the frame member 10 to the storage section 31. This allows the detection device 45, which is moving with the liquid inside the main pipe 41, to be smoothly guided into the storage section 31. The guide section 32 is also formed to be longer than the length of the frame member 10 when it is narrowed. This allows the storage section 31 containing the detection device 45 to be positioned below the hinge 12 of the frame member 10 when passing through the riser pipe 42 after collecting the detection device 45, allowing the collection member 30 to pass smoothly through the riser pipe 42.

As shown in Figure 3, the collection member 30 has a shape in which a substantially cylindrical storage section 31 is connected to a conical guide section 32. However, as shown in the figure, it is not necessarily desirable for the angle between the storage section 31 and the guide section 32 to change suddenly at the connection point; the connection point between the two may be a curved line with a gentle angle.

When the collection member 30 is inserted into the main pipe 41 and is urged downstream by the flowing liquid during the recovery of the detection device 45, it must be configured so as not to impede the flow of liquid despite being urged by the liquid. For this reason, it is preferable that the collection member 30 be configured in a mesh-like manner.

The fibers that make up the net are unlikely to stretch even when a tensile force is applied in the longitudinal direction. However, if the net is formed in a cone shape with diamond-shaped mesh, when the force associated with the flow of liquid or the force of the inflowing detection element acts, the longitudinal dimension of the cone may increase, causing deformation such that the diameter of the cone decreases (hereinafter referred to as "stretching of the collection element 30, or stretching of the shape, or stretching"). Furthermore, when the detection device collides with the net, deformation such that the net stretches locally in the lateral direction may occur.

If the collection member 30 stretches, there is a risk that the detection device 45 that has entered the guide section 32 will not be smoothly guided into the storage section 31. For this reason, the collection member 30 must be designed so that it will not stretch due to the flow of liquid or the forces acting when capturing the detection device 45.

There are no particular limitations on the means for preventing stretching of the capture member 30. For example, as shown in Figure 3, the mesh of the storage section 31 and the guide section 32 may be rectangular, consisting of vertical fibers arranged along the length of the capture member 30 and horizontal fibers woven into loops around the vertical fibers. Alternatively, as shown in Figure 4, a non-stretchable band may be arranged along the length of the capture member 30. In this case, the band is preferably a thin sheet or cloth that is impermeable or has low water permeability.

If a non-stretchable band is placed in the longitudinal direction of the collection member 30 to prevent stretching, the area where this band is placed will block the passage of liquid and at the same time act as a force that spreads the guide section 32 outward. For this reason, when using a diamond-shaped net (see Figure 4), by joining the net to the band in a state where it is spread out vertically and horizontally during the production stage of the collection member 30, it is possible to further reduce stretching.

As described above, it is preferable that the collection member 30 has passage sections 34 made of a mesh that allows liquid to pass easily and inhibition sections 35 (bands 35) made of bands that inhibit the passage of liquid, arranged alternately in the circumferential direction, and that the two be integrated by means such as stitching. The number of bands 35 arranged in the collection member 30 is preferably approximately four to six, corresponding to the dimensions of the frame member 10 when expanded, and the ratio of the surface area of the guide section 32 is preferably in the range of 1/4 to 1/2. By configuring the collection member 30 in this manner, it is possible to achieve a smooth flow of liquid. A collection member 30 configured in this manner will not stretch in shape even when subjected to forces caused by the flow of liquid or forces exerted when the detection member 45 is housed.

The structure for attaching the collection member 30 to the frame member 10 is not particularly limited, and any structure that can attach it to the frame material 11 of the frame member 10 with sufficient strength will suffice. For example, in this embodiment, a fastener 33 is attached to the end of the guide portion 32, and a fastener is also attached to the frame member 10. However, it goes without saying that a string may also be used for attachment.

In the recovery device A configured as described above, as shown in Figure 5, the frame member 10 is inserted into the main pipe 41 in a narrowed state into the pre-set riser pipe 42 of the main pipe 41, and the hinge 12 is pressed against the handle of the main pipe 41 to expand the diameter. As the frame member 10 expands in diameter, the collection member 30 expands downstream along with the liquid, completing preparations for collection by the detection device 45.

As described above, the detection device 45 is inserted into the main pipe 41 from the riser pipe 42 formed upstream of the main pipe 41, and records the sound transmitted through the liquid as it moves downstream with the liquid flowing inside the main pipe 41. The sound then flows into the collection member 30 of the recovery device A, which is located at a predetermined position, moves downstream through the induction section 32, and is stored in the storage section 31. The situation in which the detection device 45 flows into the collection member 30 and is stored in the storage section 31 is monitored by the underwater camera 23.

After confirming with the underwater camera 23 that the detection device 45 has been stored in the storage section 31 of the collection member 30, the recovery member A is removed through the riser pipe 42. At this time, even if the support member 20 is misaligned from the center of the riser pipe 42, the guide piece 22a of the guide member 22 contacts the attachment portion of the riser pipe 42 relative to the main pipe 41, guiding the support member 20 to move toward the center of the riser pipe 42. As a result, the frame member 10 is smoothly guided into the riser pipe 42.

As the support member 20 is removed, the frame member 10 is narrowed, and the detection device 45 housed in the housing portion 31 of the collection member 30 hangs down below the hinge 12 (see Figure 1). Furthermore, because the guide portion 32 is formed longer than the narrowed frame member 10, the collected detection member 45 can pass smoothly through the riser pipe 42 without interfering with it.

After removing the detection device 45 from the main pipe 41, it is possible to detect the location of the leak 43 in the main pipe 41 by removing the equipment housed in the detection device 45 and examining various data.

The recovery device of the present invention can be used to recover detection devices used to detect leaks in pipes through which various liquids flow under pressure.

A Recovery device 10 Frame member 11 Frame material 12 Hinge 20 Support member 20a Lower end portion 20b Upper end portion 21 Rotating piece 22 Guide member 22a Guide piece 23 Underwater camera 23a Cable 23b Protective cover 24 Reinforcing member 25 Extension tube 30 Collection member 31 Storage section 32 Guiding section 33 Fastener 34 Passing section 35 Inhibiting section (belt)
41 Main pipe 42 Riser pipe 43 Leaking part 45 Detector 47 Line

Claims (5)

A recovery device for recovering a cylindrical detection device that is inserted into a pipe that is thinner than a pipe through which a liquid flows and flows through the inside of the pipe together with the liquid to detect leakage of the liquid,
a frame member made of a flexible and elastic frame material, which when expanded has a substantially circular shape with a diameter slightly smaller than the inner diameter of a pipe through which a liquid flows, and when contracted has a diameter smaller than the inner diameter of a thin tube attached to the pipe;
a support member for attaching the frame member to an end portion and inserting the frame member into the piping from the thin tube;
a collection member having: a guide portion attached to the frame member, one end of which is connected to a frame material constituting the frame member, and which is formed so that when the frame member is expanded, the guide portion is formed so that the diameter decreases from a substantially circular shape having a diameter slightly smaller than the inner diameter of the piping toward the other end and is longer than the length when the frame member is contracted; and a storage portion connected to the other end of the guide portion, with a closed tip portion, formed cylindrically, and having a length longer than the length of a detection device, a diameter shorter than the length of the detection device and larger than the outer diameter of the detection device;
A recovery device comprising: The recovery device described in claim 1, characterized in that the collection member is formed in a mesh shape consisting of vertical fibers arranged in the longitudinal direction and horizontal fibers arranged independently at multiple positions in the longitudinal direction of the vertical fibers and woven into a loop shape with the vertical fibers. The recovery device described in claim 1, characterized in that the collection member has passing sections through which the liquid passes and obstructing sections that obstruct the passage of the liquid, the passing sections and obstructing sections being arranged alternately in the circumferential direction. The recovery device described in claim 3, characterized in that the passage portion of the capture member is formed in a mesh shape with a diamond-shaped mesh formed by the intersection of diagonally arranged fibers, and the inhibition portion is composed of an inelastic band arranged along the longitudinal direction of the capture member. The recovery device described in claim 1, characterized in that the frame member is made up of a pair of opposing flexible and elastic pieces, one end of which is connected to the support member via an upper hinge and the other end of which is connected to each other via a lower hinge, and the lower hinge is connected to a reinforcing member arranged along the support member.