JP2022099088A - Culvert pipe laying device - Google Patents

Abstract

To provide a culvert pipe laying device capable of simultaneously performing formation of a drain groove and laying of a culvert pipe, while maintaining a structure of a farm field.SOLUTION: A culvert pipe laying device comprises: a culvert pipe guide part 15 guiding a culvert pipe toward a bottom of a groove formed in a groove forming part 13; and a cylindrical filter material filling part 17 inserted in the groove behind the culvert pipe guide part and filling a filter material in the groove above the culvert pipe laid in the bottom of the groove. The groove forming part comprises: a sediment scooping part 27 scooping upward sediment in a part forming at least a lower half part of the groove to be formed; and a cutting part 28 sequentially connected to the sediment scooping part and expanding the sediment scooped by the sediment scooping part to both sides in a width direction. The sediment scooping part comprises an arc curved surface 30 in which an upper end is located behind a lower end on a front part side in a groove forming direction, and is provided at a position which does not exceed a height position of a rear end part RH of the lower end of the filter material filling part to allow adequate maintenance to be carried out.SELECTED DRAWING: Figure 5

Description

The present invention relates to an underdrain pipe laying device, and more particularly to an underdrain pipe laying device for laying an underdrain pipe at the bottom of a groove formed in a field and putting a hydrophobic material into the groove at the upper part of the underdrain pipe.

Conventionally, it has been practiced to improve the drainage property of a field by forming a drainage ditch in the ground of the field and forming a rice husk culvert filled with a hydrophobic material such as rice husk in the ditch. The drainage ditch forming device for forming the rice husk culvert is basically a blade-shaped groove forming portion that is inserted under the ground to cut out the groove, and a hopper for throwing rice husks that is connected to the rear part of the groove forming portion. By throwing rice husks into the hopper while pulling the drainage ditch forming device by a traveling body such as a tractor, the rice husk culvert is continuously formed (for example, Patent Documents 1 and 1). See a few.).

Japanese Patent No. 4621443 Japanese Unexamined Patent Publication No. 2018-178508 Japanese Unexamined Patent Publication No. 2019-129821

However, in the drainage culvert forming apparatus described in Patent Document 1, since it is necessary to form a guide groove with a blade as a pretreatment for starting excavation formation of the drainage culvert, the work takes time and effort. .. Further, in the groove forming portion described in Patent Document 2, a large force is required to push and spread the earth and sand depending on the field, and there is a problem that the vehicle towing the device becomes large. In particular, as the groove to be formed becomes deeper, the weight of the upper layer portion is added to the earth and sand in the lower layer that expands, and the resistance further increases. In the worst case, the wheel slips and the traction force becomes insufficient. Further, in the drainage ditch forming device described in Patent Document 3, due to the shape of the earth and sand scraping portion having a large height dimension, stones and gravel in the lower layer may be dug up or the structure of the soil layer may be changed. Since it is brought about, labor is required for post-treatment for removing these, and there is a possibility that the subsequent work in the field may be hindered. Various devices for forming such drainage culverts have been improved from various viewpoints, but they have not been sufficient for proper maintenance of highly productive fields.

Therefore, an object of the present invention is to provide an underdrain pipe laying device capable of laying an underdrain pipe at the same time as forming a drainage ditch while maintaining the structure of the field.

In order to achieve the above object, the underdrain pipe laying device of the present invention has a groove forming portion that forms a groove in the ground while being pulled by a traveling body, and a groove formed by the groove forming portion behind the groove forming portion. An underdrain pipe guide portion that guides an underdrain pipe having flexibility toward the bottom, and an underdrain pipe that is inserted into the groove behind the underdrain pipe guide portion and laid in the bottom of the groove in the groove above the underdrain pipe. In an underdrain pipe laying device provided with a tubular hydrophobic material filling portion for filling the hydrophobic material and a hopper for dropping the hydrophobic material into the hydrophobic material filling portion from above the hydrophobic material filling portion, the groove forming portion is , The earth and sand scraping part that scrapes up the earth and sand of the part that forms at least the lower half of the groove to be formed, and the earth and sand scraping part that is connected to the earth and sand scraping part The earth and sand scraping portion is composed of a cutting portion that expands and has an arc curved surface in which the upper end is located rearward with respect to the lower end on the front end side in the groove forming direction, and the height of the lower end rear end portion of the hydrophobic material filling portion. It is characterized by being installed at a position that does not exceed the position.

Further, the cutting portion has a cutting plate having a plate end facing the front side in the groove forming direction and a pair of widening plates provided on both side surfaces of the cutting plate so as to be inclined symmetrically with each other. The scraped-up portion is characterized in that the arc curved surface is composed of a plate surface obtained by bending a plate material, and the horizontal cross section is formed in a T shape with the plate material fixed to the plate end of the cutting plate. There is.

According to the underdrain pipe laying device of the present invention, a sediment scooping portion in which the groove forming portion forms at least the lower half of the groove, and a cutting portion that pushes and spreads the earth and sand scooped up by the sediment scooping portion on both sides in the width direction. Therefore, it is possible to use the propulsive force of the traveling body to lift the lower layer of earth and sand that is difficult to move laterally and reduce the weight applied to the earth and sand. As a result, it is possible to easily form a drainage ditch even when the device is towed by a relatively small traveling body because the lateral displacement operation by the cutting portion can be performed with a small force on the lifted earth and sand. be able to. Moreover, since the earth and sand scraping portion is provided at a position that does not exceed the height position of the lower end rear end portion of the hydrophobic material filling portion, it is possible to prevent problems such as stones and gravel being raised to the soil layer. That is, an underdrain pipe laying device that does not require pretreatment or posttreatment for the field to be constructed is realized, which contributes to appropriate maintenance of a highly productive field.

It is a side view which shows one embodiment example of the underdrain pipe laying apparatus of this invention. It is also a plan view of the underdrain pipe laying device. Similarly, it is a front view seen from the rear side in the traveling direction of the underdrain pipe laying device. Similarly, it is a perspective view of a main part seen from the front side in the traveling direction of the underdrain pipe laying device. Similarly, it is a cross-sectional perspective view of a main part seen from the front side in the traveling direction of the underdrain pipe laying device. Similarly, it is a perspective view of a main part seen from the rear side in the traveling direction of the underdrain pipe laying device. Similarly, it is a front view of a main part seen from the front side in the traveling direction of the underdrain pipe laying device. Similarly, it is a front view of the main part seen from the rear side in the traveling direction of the underdrain pipe laying device. It is a plan view of a main part. FIG. 8 is a cross-sectional view taken along the line XX of FIG. FIG. 10 is a cross-sectional view taken along the line XI-XI of FIG. FIG. 10 is a cross-sectional view taken along the line XII-XII of FIG. FIG. 10 is a cross-sectional view taken along the line XIII-XIII of FIG. FIG. 10 is an arrow view of XIV-XIV of FIG. FIG. 14 is a cross-sectional view taken along the line XV-XV of FIG.

1 to 15 show an example of an underdrain pipe laying device of the present invention. The underdrain pipe laying device 10 shown in this embodiment is provided at the lower part on the front side of the rectangular basic frame 11, and is a groove forming portion 13 for excavating and forming a groove 12 having a predetermined shape in the ground of the field. And, behind the groove forming portion 13, the underdrain pipe guide portion 15 for guiding the underdrain pipe 14 to the bottom of the groove 12 formed by the groove forming portion 13, and the groove behind the underdrain pipe guide portion 15. A hopper for dropping the hydrophobic material 16 into the hydrophobic material filling portion 17 from above the hydrophobic material filling portion 17 inserted into the hydrophobic material filling portion 17 for filling the hydrophobic material 16 such as rice husks. The work deck portion 19 in the horizontal direction provided around the rectangular opening 18a opened at the upper end of the hopper 18, and the three sides of the opening 18a facing upward from the upper surface of the work deck portion 19. A hydrophobic material guide plate 20 projecting in the vertical direction, an underdrain pipe pressing member 21 for pressing the underdrain pipe 14 sent from the underdrain pipe guide portion 15 to the bottom of the groove 12 toward the bottom surface of the groove 12, and the above-mentioned. The hydrophobic material height setting member 22 provided at the upper part of the rear end of the hydrophobic material filling portion 17 and setting the filling height of the hydrophobic material 16 to be filled in the groove 12, and the said on the rear side one side of the basic frame 11. A reel holding portion 24 for rotatably holding the hose reel 23 around which the underdrain pipe 14 is wound is provided, and the front end portion of the basic frame 11 is connected to the rear portion of the bulldozer 51 which is a kind of traveling body. A traveling body connecting portion 25 is provided, and an upper end of the underdrain pipe guide portion 15 is opened at the front portion of the hopper 18, and a laser receiver 26 for detecting the vertical position of the underdrain pipe laying device 10 is attached. Has been done.

The underdrain pipe 14 is made of a long and flexible synthetic resin having a large number of through holes formed on its peripheral surface, and the underdrain pipe 14 having a predetermined length is wound around a hose reel 23. There is. Further, the underdrain pipe 14 having an appropriate diameter is selected according to the condition of the field and the like. The reel holding portion 24 is formed in the same manner as the reel holding portion conventionally provided in this type of underdrain pipe laying device, and the underdrain pipe 14 of the hose reel 23 held by the reel holding portion 24 is exhausted and the hose reel. When 23 became empty, the work was temporarily stopped, the empty hose reel 23 was removed, a new hose reel 23 around which the underdrain pipe 14 was wound was attached to the reel holding portion 24, and the rear end of the front underdrain pipe 14 was attached. After connecting to the tip of a new underdrain pipe 14, the work is resumed.

The underdrain pipe guide portion 15 is formed of a tubular body having an inner surface dimension larger than the maximum outer diameter of the underdrain pipe 14, and is rearward of the groove forming portion 13 in a forward leaning posture in consideration of the movement of the underdrain pipe 14 to be inserted. It is provided along the line. At the upper end of the underdrain pipe guide portion 15, the insertion port 15a of the underdrain pipe 14 unwound from the hose reel 23 is opened upward, and the lower end portion of the underdrain pipe guide portion 15 is bent rearward. At the lower end, an outlet 15b for sending the underdrain pipe 14 toward the bottom of the groove 12 is opened toward the rear.

The hydrophobic material filling portion 17 has an outer surface width dimension corresponding to the inner surface width dimension of the groove 12, is formed in a flat square cylinder shape with an opening in the vertical direction, and the lower end edge is a feed of the underdrain pipe guide portion 15. An inclination that rises rearward from the lower end front end FH located at the upper edge of the outlet 15b is provided, and the lower end rear end RH corresponds to the maximum filling height of the hydrophobic material 16 to be filled in the groove 12. It is provided at the position. The filling height of the hydrophobic material 16 varies depending on the field, but at least considering the thickness of the soil layer (about 15 to 20 cm) required for the growth of plants called the soil layer, the depth of the groove 12 is 60 to 70. %, For example, if the depth of the groove 12 is 80 cm, the filling height of the hydrophobic material 16 is set to about 50 cm. As a result, the soil layer and the packed layer of the hydrophobic material 16 are vertically partitioned in the groove 12 in which the underdrain pipe 14 is laid.

The groove forming portion 13 is a welded structure in which a plurality of steel plate materials are combined to form a groove 12 having a predetermined depth, for example, a depth of about 50 to 80 cm, and forms at least the lower half of the groove 12. It is provided with an earth and sand scraping section 27 that scrapes up the earth and sand in the portion to be scraped upward, and a cutting section 28 that is connected to the earth and sand scraping section 27 and pushes and spreads the earth and sand scraped up by the earth and sand scraping section 27 on both sides in the width direction. ing.

The earth and sand scraping portion 27 is sharpened so that the lower end on the front side in the groove forming direction is connected to the tip of the bottom plate 29 and the earth and sand at the bottom surface of the groove 12 is scraped up to form the groove bottom surface. It has an arc curved surface 30 whose upper end is located rearward with respect to the lower end. The arc curved surface 30 is a plate surface formed by bending a steel plate material, has a width dimension corresponding to the groove width to be formed, and a plane passing through the front end and the rear end is between the plate surface of the bottom plate 29. It has an inclination of about 45 degrees. Further, the earth and sand scraping portion 27 is provided at a height position that does not exceed the height position of the lower end rear end portion RH of the hydrophobic material filling portion 17. That is, for example, when forming a groove 12 having a depth of 80 cm, the earth and sand scraping portion 27 has a height dimension of 40 cm corresponding to at least the lower half of the groove 12, and is behind the lower end of the hydrophobic material filling portion 17. By being provided at a position defined by the end portion RH, that is, at a position where the filling height of the hydrophobic material 16 does not exceed 50 cm, the space between the upper and lower parts of the earth and sand scraping portion 27 (arc curved surface 30) in the groove 12 and the soil layer. An intermediate layer having a thickness of about 10 to 20 cm is secured. As a result, even if the earth and sand scraped up by the earth and sand scraping portion 27 move upward, stones, gravel, etc. buried in the lower layer in the soil do not rise to the soil layer but stay in the middle layer. become.

The cutting portion 28 has a cutting plate 31 with the plate end 31a of the steel plate material facing the front side in the groove forming direction, and a pair of widening plates 32, 32 in the width direction provided on both sides of the cutting plate 31. There is. The cutting plate 31 is formed so that the upper side of the plate end 31a extends in the vertical direction along the inclination of the underdrain pipe guide portion 15, and the lower side has a protruding shape matching the shape of the arc curved surface 30. Both widening plates 32, 32 have a width dimension corresponding to the groove width to be formed in a combined state, and both side surfaces of the cutting plate 31 so that the width dimension is wider than the maximum outer diameter of the underdrain pipe 14. The outer end portion is continuously provided on the outer surface of the underdrain pipe guide portion 15. As a result, the earth and sand scraping portion 27 integrated with the cutting portion 28 has increased strength with respect to the groove forming direction, and as shown in FIGS. 11 and 12, a steel plate material having an arcuate curved surface 30 is cut into a cutting plate. In a state of being fixed to the plate end 31a of 31, a horizontal cross section is formed in a T shape, and a space S is provided between the back surface of the arc curved surface 30 and the front and rear of both widening plates 32, 32.

The hopper 18 connected to the upper part of the hydrophobic material filling portion 17 is formed in a rectangular funnel shape with the upper side widened in the left-right direction with respect to the lower end opening formed in the same shape as the upper opening of the hydrophobic material filling portion 17. A rectangular opening 18a is formed at the upper end thereof. Further, the left and right side walls 18b and 18b from the upper opening of the hydrophobic material filling portion 17 toward the upper end opening 18a are formed of curved surfaces that are gently convex toward the inside of the hopper 18, and the hydrophobic material 16 is formed. I try to make it fall smoothly. The capacity of the hopper 18 is formed to be the capacity of one bag containing a hydrophobic material that is generally distributed, for example, about 100 liters, and the height of the opening 18a is about 20 to 40 cm from the ground. Is set to.

Further, a pressing position adjusting member 33 for adjusting the height position of the underdrain tube pressing member 21 is provided in the vertical direction of the front end surface from the hydrophobic material filling portion 17 to the hopper 18, and the hydrophobic material is provided in the vertical direction of the rear end surface. A filling height adjusting member 34 for adjusting the height position of the height setting member 22 is provided.

In the underdrain pipe pressing member 21, the other end of the L-shaped link lever 21b to which the pressing roller 21a is rotatably attached to one end is between the left and right connecting plates for connecting the underdrain pipe guide portion 15 and the hydrophobic material filling portion 17. A slit that is rotatably supported by a support shaft 21c provided in the center of the link lever 21b and in which the lower end of the link rod 33a of the pressing position adjusting member 33 is slidably engaged in the front-rear direction. 21d is formed.

A stopper pin 33b projecting forward of the hopper 18 is provided at the upper end of the link rod 33a, and a disk-shaped locking member for locking the stopper pin 33b is provided on the outer surface of the front hydrophobic material guide plate 20. 35 is rotatably attached. The disk-shaped locking member 35 is provided with four radial insertion grooves 35a having different depths and locking grooves 35b bent in the circumferential direction from the inner end of the insertion groove 35a, and has a disk-shaped locking member 35. The locking member 35 is rotated so that the insertion groove 35a having a predetermined depth is directed upward, the stopper pin 33b is inserted into the insertion groove 35a from above, and then the disk-shaped locking member 35 is rotated to rotate the locking groove 35b. By locking the stopper pin 33b to the end portion of the button, the pressing roller 21a can be fixed at a predetermined height via the link rod 33a and the link lever 21b. As a result, the height of the pressing roller 21a can be adjusted in four stages between the lowest lowering position corresponding to the minimum diameter underdrain pipe shown by the solid line in FIG. 10 and the highest rising position shown by the imaginary line. The locked state of the insertion groove 35a and the stopper pin 33b is prevented from being disengaged by the vibration of the time.

Further, in the hydrophobic material height setting member 22, a rectangular adjusting plate 22b long in the vertical direction is slidably mounted between the pair of left and right guide members 22a and 22a provided on the rear outer surface of the hopper 18. The filling height adjusting member 34 has an adjusting lever 36 provided via a connecting rod 34a connected to the upper end portion of the adjusting plate 22b. The adjusting lever 36 is rotatably attached to a support shaft 36b fixed to a support plate 36a protruding from the side of the rear hydrophobic material guide plate 20 at one end, and the hydrophobic material guide plate 20 is rotatably attached to the other end. A meshing member 36d that meshes with the arc-shaped locking tooth member 36c provided on the outer surface is provided. The locking tooth member 36c is provided with a plurality of locking teeth, and is connected by rotating the other end of the adjusting lever 36 in the vertical direction to lock the meshing member 36d to a predetermined locking tooth. The adjusting plate 22b can be adjusted to a predetermined height via the rod 34a, and the filling height of the hydrophobic material 16 can be set to a predetermined height. Further, by locking the locking tooth member 36c and the meshing member 36d, the locked state is prevented from being released due to vibration during work.

The work deck portion 19 in this embodiment is provided on the left side of the opening 18a of the hopper 18 in the direction of travel during work, and a bag in which one or more workers stand and a predetermined amount of hydrophobic material 16 is packed. Has a size that allows one or more to be placed. Further, it is formed to have a space for placing a basket or a box for collecting an empty bag after the hydrophobic material is put in. The upper surface of the work deck portion 19 is flush with the upper end edge of the opening 18a so that a step does not occur. Further, in order to insert the underdrain pipe 14 into the underdrain pipe guide portion 15 and to connect the rear end and the front end of the underdrain pipe 14 to the front portion on the right side of the opening 18a of the hopper 18 in the traveling direction during work. Auxiliary deck portion 19a is provided.

The hydrophobic material guide plate 20 is provided on the front side, the rear side, and the right side in the working direction with respect to the opening 18a of the hopper 18 so as to surround three sides of the upper opening, and the work deck portion 19 is provided. It is not provided on the left side. The height of the hydrophobic material guide plate 20 is set so that the hydrophobic material 16 does not scatter around when the hydrophobic material 16 is put into the hopper 18, and the hydrophobic material 16 is put from above the work deck portion 19. It is preferable to form the hydrophobic material guide plate 20 on the right side in the traveling direction during work facing the direction higher than the others. Further, by projecting the hydrophobic material guide plate 20 on the rear side in the traveling direction during work toward the work deck portion 19, safety to the rear during work is also improved.

Further, in the underdrain pipe laying device 10 shown in this embodiment, a hydrophobic material stirring member 37 for loosening the hydrophobic material 16 is provided inside the hopper 18. The hydrophobic material stirring member 37 has a plurality of stirring blades 37b projecting around a rotating shaft 37a rotatably supported on the front and rear walls of the hopper 18 at both ends, and is connected to one end of the rotating shaft 37a. By rotating the rotating shaft 37a with the driving means 37c such as an electric motor or a hydraulic motor and stirring the hydrophobic material 16 with the stirring blade 37b, it is possible to more reliably prevent the formation of a bridge in the hydrophobic material 16.

In the field where the underdrain pipe laying device 10 thus formed is used, a soil layer from which stones, gravel and the like have been removed during plowing is formed. When the underdrain pipe 14 is laid at a predetermined depth from the ground surface in such a field, the underdrain pipe laying device 10 travels on the parallel link member 51a provided at the rear of the bulldozer 51, which is a self-propelled traveling body. The culvert pipe laying work is performed with the body connecting portion 25 connected.

The position of the bottom surface of the groove 12 in the underdrain pipe laying work, that is, the movement locus drawn by the lower end of the earth and sand scraping portion 27 of the groove forming portion 13 is a cylinder provided on the parallel link member 51a by the reference laser light received by the laser receiver 26. By expanding and contracting the 51b, the height is adjusted so that a constant water gradient can be obtained. In addition, before performing the underdrain pipe laying work, bags containing hydrophobic materials are arranged at predetermined intervals along the underdrain pipe laying position. In the work of arranging the bag containing the hydrophobic material, the bag containing the hydrophobic material placed on the loading platform of an appropriate traveling body such as a truck should be dropped on the ground at intervals according to the amount of the hydrophobic material 16 put into the groove. Just do it.

The culvert pipe laying work is performed by moving the bulldozer 51 at a predetermined speed, for example, a walking speed. At this time, one of the workers puts a bag containing a hydrophobic material placed on the ground on the upper surface of the work deck portion 19 while walking along with the movement of the underdrain pipe laying device 10. Another worker opened the bag by cutting one end of the bag containing the hydrophobic material placed on the upper surface of the work deck portion 19 while riding on the work deck portion 19, and the opened part was opened. After the bag is tilted so as to be inside the opening 18a of the hopper 18, the other end of the bag is lifted and the hydrophobic material 16 in the bag is put into the hopper 18. At this time, since the upper surface of the work deck portion 19 and the upper edge of the opening are flush with each other, even if the hydrophobic material falls on the work deck portion 19, it can be easily thrown into the hopper 18. ..

With the movement of the underdrain pipe laying device 10 towed by the bulldozer 51, the earth and sand scraping portion 27 and the cutting portion 28 in the groove forming portion 13 act simultaneously, and have a predetermined depth (for example, 60 cm) and a predetermined width (for example, 14 cm). The vertical groove 12 is formed. At this time, a part of the loosened earth and sand wraps around the back surface (space S) of the earth and sand scraping portion 27, but the earth and sand abut on the widening plate 32 of the subsequent cutting portion 28 and are pushed out to both sides in the width direction. Further, the low-rise sediment scraped up by the sediment scraping portion 27 may contain stones and gravel, which are formed along the arc curved surface 30 of the sediment scraping portion 27 at the same time as the formation of the groove 12. After being lifted, it abuts on the widening plate 32 and is pushed away to the left or right in the width direction.

Here, the earth and sand scraping portion 27 has a height dimension corresponding to at least the lower half portion (for example, 30 cm) of the groove 12, and the position defined by the lower end rear end portion RH of the hydrophobic material filling portion 17. That is, since the hydrophobic material 16 is provided at a position not exceeding the filling height (for example, 40 cm), an intermediate layer is secured between the upper and lower parts of the earth and sand scraping portion 27 and the soil layer in the groove 12. As a result, even if the earth and sand scraped up by the earth and sand scraping portion 27 move upward, stones and gravel do not rise to the soil layer and are stopped in the intermediate layer.

In the groove 12 thus formed, when the underdrain pipe 14 guided by the underdrain pipe guide portion 15 is continuously delivered to the bottom of the groove 12, the pressing roller 21a adjusted to a predetermined position by the pressing position adjusting member 33 Presses the underdrain pipe 14 against the bottom surface of the groove 12, so that the underdrain pipe 14 is surely laid along the bottom surface of the groove 12. Then, the hydrophobic material 16 thrown into the hopper 18 is filled into the groove 12 from the lower opening of the hydrophobic material filling portion 17 so as to cover the upper part of the underdrain pipe 14 at the bottom of the groove. Further, by adjusting the height of the adjusting plate 22b of the filling height adjusting member 34 with the adjusting lever 36, the filling height of the hydrophobic material 16 is kept uniform at a desired height.

As described above, according to the underdrain pipe laying device 10 of the present invention, the earth and sand scraping portion 27 in which the groove forming portion 13 forms at least the lower half of the groove 12 and the earth and sand scooped up by the earth and sand scraping portion 27 are collected. Since it is composed of a cutting portion 28 that expands on both sides in the width direction, it is possible to lift the lower layer earth and sand that is difficult to move laterally by using the propulsive force of the traveling body and reduce the weight applied to the earth and sand. As a result, the lifted earth and sand can be displaced laterally by the cutting portion 28 with a small force, so that a drainage ditch can be easily formed even when the device is towed by a relatively small traveling body. can do. Moreover, since the earth and sand scraping portion 27 is provided at a position not exceeding the height position of the lower end rear end portion RH of the hydrophobic material filling portion 17, it is possible to prevent problems such as stones and gravel being raised to the soil layer. That is, the underdrain pipe laying device 10 that does not require pretreatment or posttreatment for the field to be constructed is realized, and contributes to appropriate maintenance of the highly productive field.

Further, the cutting portion 28 has a cutting plate 31 with the plate end 31a facing the front side in the groove forming direction, and a pair of widening plates 32, 32 provided on both side surfaces of the cutting plate 31 so as to be inclined symmetrically with each other. Since the horizontal cross section is formed in a T shape with the plate material having the earth and sand scraping portion 27 having the arc curved surface 30 fixed to the plate end 31a of the cutting plate 31, the back surface of the arc curved surface 30 is formed. A structure in which a space S is provided between the front and rear of the widening plates 32 and 32 can be achieved at low cost. As a result, when the groove 12 is formed, the side wall of the formed groove 12 is not pressed, so that the resistance when forming the groove 12 is significantly reduced, and the impermeable wall is not formed, and the groove is formed. Occasionally, the earth and sand on the side wall portion becomes loosened, and the water in the ground easily flows into the groove 12, so that the drainage effect can be improved.

The underdrain pipe laying device of the present invention is not limited to the above-mentioned embodiment, and the size of the groove forming portion is such that the earth and sand can be raised from the lower layer to the middle layer to reduce the resistance at the time of forming the groove. Often, depending on the conditions such as the shape and depth of the groove required for laying the underdrain pipe and the thickness of the soil layer, for example, the width of the earth and sand scraping part and the cutting part may be slightly different. Can be changed as appropriate. In addition, after defining the arrangement of the earth and sand scraping portion in the height direction in relation to the position of the lower end rear end portion of the hydrophobic material filling portion, the substantially right triangle with the arc curved surface as the hypotenuse should be enlarged or reduced in a similar manner. For example, since a groove forming portion having a size (size) suitable for various conditions can be obtained, it is possible to widely cope with various environments in which the underdrain pipe laying device is used.

10 ... Underdrain pipe laying device, 11 ... Basic frame, 12 ... Groove, 13 ... Groove forming part, 14 ... Underdrain pipe, 15 ... Underdrain pipe guide part, 15a ... Insertion port, 15b ... Outlet, 16 ... Hydrophobic material, 17 ... Hydrophobic material filling part, 18 ... Hopper, 18a ... Opening, 18b ... Side wall, 19 ... Working deck part, 19a ... Auxiliary deck part, 20 ... Hydrophobic material guide plate, 21 ... Underdrain pipe pressing member, 21a ... Pressing roller, 21b ... Link lever, 21c ... Support shaft, 21d ... Slit, 22 ... Hydrophobic material height setting member, 22a ... Guide member, 22b ... Adjustment plate, 23 ... Hose reel, 24 ... Reel holding part, 25 ... Traveling body connecting part , 26 ... Laser receiver, 27 ... Sediment scraping part, 28 ... Cutting part, 29 ... Bottom plate, 30 ... Arc curved surface, 31 ... Cutting plate, 31a ... Plate edge, 32 ... Widening plate, 33 ... Pressing position adjusting member, 33a ... Link rod, 33b ... Stopper pin, 34 ... Filling height adjusting member, 34a ... Connecting rod, 35 ... Disc-shaped locking member, 35a ... Insert groove, 35b ... Locking groove, 36 ... Adjusting lever, 36a ... Support Plate, 36b ... Support shaft, 36c ... Locking tooth member, 36d ... Meshing member, 37 ... Hydrophobic material stirring member, 37a ... Rotating shaft, 37b ... Stirring blade, 37c ... Drive means, 51 ... Bulldozer, 51a ... Parallel link member , 51b ... Cylinder

Claims (2)

A groove forming portion that forms a groove in the ground while being pulled by a traveling body, and an underdrain pipe that guides a flexible underdrain pipe toward the bottom of the groove formed by the groove forming portion behind the groove forming portion. A guide portion, a tubular hydrophobic material filling portion inserted into the groove behind the underdrain pipe guide portion, and a tubular hydrophobic material filling portion filled in the groove above the underdrain pipe laid at the bottom of the groove, and the underdrain pipe. In an underdrain pipe laying device provided with a hopper for dropping the hydrophobic material from above the hydrophobic material filling portion into the hydrophobic material filling portion.
The groove forming portion is connected to an earth and sand scraping portion that scrapes up the earth and sand in a portion forming at least the lower half of the groove to be formed, and the earth and sand scraping portion, and the earth and sand that is scraped up by the earth and sand scraping portion. Consists of a cutting part that expands on both sides in the width direction
The earth and sand scraping portion has an arc curved surface whose upper end is located rearward with respect to the lower end on the front end side in the groove forming direction, and is provided at a position not exceeding the height position of the lower end rear end portion of the hydrophobic material filling portion. An underdrain pipe laying device characterized by being installed. The cutting portion has a cutting plate having a plate end facing the front side in the groove forming direction, and a pair of widening plates provided on both side surfaces of the cutting plate so as to be inclined symmetrically with each other.
The earth and sand scraping portion has a plate surface in which the arc curved surface is bent, and the horizontal cross section is formed in a T shape with the plate material fixed to the plate end of the cutting plate. The underdrain pipe laying device according to claim 1, which is characterized.

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