JP6308937B2 - Sediment scraping machine and sediment scraping method - Google Patents

Description

  The present invention is a sediment tanker for scraping the precipitate in the settling tank to the pit in a settling tank for precipitating impurities contained in liquid (treated liquid) such as clean water and sewage, And a method of scraping the precipitate.

  In water treatment such as clean water and sewage and liquid treatment in food production, a precipitation tank for separating impurities contained in the liquid as a precipitate is used. In the sedimentation tank, impurities contained in the liquid settle on the bottom surface of the sedimentation tank due to their own weight, and deposit as sediment (for example, sludge) on the bottom surface. Therefore, in order to discharge the sediment from the sedimentation tank, the sediment is scraped to a pit provided at one end of the bottom surface of the sedimentation tank using a sediment scraper.

  The sediment scraping machine has a scraping cart for scraping the sediment into the pit, and reciprocates the scraping cart a predetermined number of times from one end to the other end in the sedimentation tank. By this reciprocating movement, the sediment deposited on the bottom surface of the sedimentation tank is scraped to the pit.

  However, the amount of sediment in the sedimentation tank usually decreases gradually from the liquid inflow side to the discharge side in the sedimentation tank. That is, there is the most precipitate on the inflow side and a smaller amount of precipitate on the discharge side. For this reason, the scraping cart that reciprocates from one end to the other end of the sedimentation tank has also moved for the scraping operation even on the bottom surface where there is no sediment, and wastes energy. Further, if the scraping cart is operated in vain, the life of consumable parts such as a traction tool, a traveling wheel, a roller, or a traveling guide rail constituting the sediment scraping machine is shortened.

  Patent Document 2 discloses that the amount of sludge accumulated is detected from a load applied to a drive chain that pulls the underwater cart, and the underwater cart is reversely driven at the detection position. However, in reality, the apparent density of sludge in water is equivalent to that of water, so the load on the drive chain may be smaller than expected, and the underwater carriage may not run backward at the intended position. .

Japanese Unexamined Patent Publication No. 64-47415 JP 59-162916 A

  The present invention has been made in view of the above-described conventional problems, and an object thereof is to provide a sediment scraper that is energy saving and can extend the life of a consumable part. Moreover, an object of this invention is to provide the sediment scraping method. Furthermore, the present invention can detect the position of the scraping carriage in the sedimentation tank without disposing a position detector in the sedimentation tank, and the precipitation that can reversely run the scraping truck at a desired position. The purpose is to provide a scraper.

One reference example of the present invention for solving the above-described problem is that the deposit accumulated on the bottom surface of the settling tank is scraped into a pit provided on the bottom surface of the settling tank by traveling in the settling tank. A trolley, a position detector that detects whether or not the scraper has reached a predetermined position, and a controller that controls the travel of the scraper, wherein the predetermined position is the pit. And a plurality of reversing positions for reversing the traveling direction of the scraping cart traveling in a direction away from the pit, and the control unit includes the deposit charging position, A sediment scraper that causes the scraping carriage to perform at least one scraping step of reciprocating the scraping carriage between any one of the plurality of reverse positions selected in advance. is there.

In a preferred aspect of the reference example, the at least one scraping step is a plurality of scraping steps, and the plurality of scraping steps include the scraping carriage, the deposit input position, and the plurality of scraping steps. A first scraping step of reciprocating between a first reversing position selected in advance from a reversing position, and the scraping cart, pre-selected from the deposit input position and the plurality of reversing positions, And a second scraping step of reciprocating between a second reverse position different from the first reverse position.

One aspect of the present invention is a sediment scraping method for scraping the sediment deposited on the bottom surface of the sedimentation tank using a scraping carriage to a pit provided in the sedimentation tank, on the bottom surface of the sedimentation tank. The scraping cart is caused to travel by a drive device, the rotational speed of the drive shaft is reduced by a reduction device connected to the drive shaft of the drive device, and the scraping cart is moved by a moving mechanism connected to the reduction device. The position indicator is moved at a speed slower than that of the scraping carriage, the position indicator is detected by the position detector, and the scraper is detected based on the position indicator position. It is a sediment scraping method characterized by reversing the traveling direction of the carriage .

In a preferred aspect of the reference example, the at least one scraping step is a plurality of scraping steps, and the plurality of scraping steps include the scraping carriage, the deposit input position, and the plurality of scraping steps. A first scraping step of reciprocating between a first reversing position selected in advance from a reversing position, and the scraping cart, pre-selected from the deposit input position and the plurality of reversing positions, And a second scraping step of reciprocating between a second reverse position different from the first reverse position.

One embodiment of the present invention includes a scraping cart that scrapes the sediment deposited on the bottom surface of the sedimentation tank to a pit provided on the bottom surface of the sedimentation tank, and a drive that drives the scraping cart on the bottom surface of the sedimentation tank. In synchronization with the travel of the scraping carriage, and a device, a speed reducer coupled to the drive shaft of the drive device and decelerating the rotational speed of the drive shaft, a moving mechanism coupled to the speed reducer, A position indicator that is moved by the moving mechanism at a slower speed than the scraping carriage, a position detector that detects a position of the position indicator, and a traveling direction of the scraping carriage based on the position of the position indicator And a control unit that reverses the sediment.

In a preferred aspect of the present invention, the position indicator is arranged outside the settling tank.
In a preferred aspect of the present invention, an inclined plate is disposed in the settling tank, and the position where the traveling direction of the scraping carriage is reversed is between the lower position of the inclined plate and the upper position of the pit. It is characterized by being.
A preferred embodiment of the present invention further comprises a settling plate disposed in the settling tank, and a tilting mechanism for tilting the settling plate, and after the tilting mechanism tilts the settling plate, the scraping carriage is And traveling under the settling plate.
In a preferred aspect of the present invention, the position where the traveling direction of the scraping carriage is reversed is between the lower position of the sinking plate and the upper position of the pit.

  According to the present invention, the scraping cart travels in the opposite direction when the scraping cart reaches the preset reverse position. That is, by setting the reversal position in advance according to the expected sediment distribution, the scraping cart can be moved at a shorter distance than the operation of the conventional scraping cart that reciprocates from one end to the other end of the sedimentation tank. It can move and scrape sediment efficiently. As a result, the scraping cart does not move unnecessarily, which saves energy and extends the life of consumable parts.

  Further, according to the present invention, the position indicator moves at a slower speed in synchronization with the scraping carriage in the settling tank. Therefore, the control unit can detect the position of the scraping carriage in the settling tank based on the position of the position indicator, and can further control the movement of the scraping carriage.

It is a schematic side view of the sediment scraping machine which concerns on one Embodiment of this invention. It is a schematic plan view of the sediment scraping machine which concerns on one Embodiment of this invention. FIG. 3 is a schematic side view showing a state where a scraping carriage in the sediment scraper shown in FIG. 1 and FIG. 2 scrapes the sediment into a pit. It is the schematic side view which showed the state which the scraping cart in the deposit scraper shown in FIG. 1 and FIG. 2 is drive | moving in the direction away from a pit. It is the schematic which showed the first half part of the process which scrapes a sediment with the conventional sediment scraping machine. It is the schematic which showed the latter half part of the process which scrapes a deposit with the conventional deposit scraper. It is the schematic which showed the first half part of the process which scrapes a sediment with the sediment scraper of this embodiment. It is the schematic which showed the second half part of the process which scrapes a deposit with the deposit scraping machine of this embodiment. It is a schematic side view which shows embodiment with which the inclination board was attached to the sedimentation tank. It is the schematic side view which looked at the settling tank shown by FIG. 9 from the liquid inflow port side of the said settling tank. It is a schematic plan view of the sediment scraping machine which concerns on other embodiment of this invention. It is a figure which shows the other structural example of a moving mechanism. It is a figure which shows embodiment which integrated the inclination board shown in FIG. 9 and FIG. 10 in embodiment shown in FIG. It is a figure which shows embodiment which incorporated the sedimentation board in embodiment shown in FIG. It is AA sectional view taken on the line shown in FIG. It is a perspective view which shows the row | line | column of the sedimentation board arranged along the perpendicular direction. It is the figure which looked at the sedimentation board in a horizontal state from the short side of the sedimentation board. It is the figure which looked at the state where only the odd-numbered stage sedimentation board inclined from the short side of the sedimentation board. It is the figure which looked at the state in which only the even number stage sedimentation board inclined from the short side of the sedimentation board.

Embodiments of the present invention will be described below with reference to the drawings.
The embodiment described below is a settling basin as a settling tank used for water treatment of clean water or sewage, but the present invention can be applied to other types of settling tanks as long as precipitates are generated. For example, it may be a sedimentation tank used in a food production process.

  FIG. 1 is a schematic side view of a sediment scraper according to an embodiment of the present invention. FIG. 2 is a schematic plan view of a sediment scraper according to an embodiment of the present invention. As shown in FIG. 1, the sediment scraper is disposed in a sedimentation tank 1 for sedimenting impurities in a liquid (liquid to be treated) and depositing it as a sediment. A plurality of liquid inlets 2 for introducing a liquid (liquid to be processed) into the precipitation tank 1 are provided on the wall of the precipitation tank 1. The liquid flowing in through the liquid inlet 2 flows toward the other wall opposite to the wall where the liquid inlet 2 is provided. In the process in which the liquid flows in this way, impurities contained in the liquid are settled and deposited as a precipitate on the bottom surface of the precipitation tank 1.

  As shown in FIG. 1 and FIG. 2, the sediment scraper 3 travels in the sedimentation tank 1, and deposits on the bottom surface of the sedimentation tank 1 are provided in the pit 10 provided on the bottom surface of the sedimentation tank 1. And a wire 6 as a traction tool for reciprocating the scraping cart 5. The pit 10 is provided at one end of the bottom surface of the sedimentation tank 1 and is adjacent to the wall provided with the liquid inlet 2.

  On the bottom surface of the settling tank 1, two guide rails 12 and 12 parallel to each other are installed horizontally. The scraping cart 5 has a rotatable traveling wheel 13, and the traveling wheel 13 is placed on the guide rails 12 and 12. Therefore, the scraping cart 5 can travel on the guide rails 12 and 12. The scraping cart 5 further includes a scraping plate 7 for scraping the deposit on the bottom surface of the sedimentation tank 1. The scraping plate 7 is configured to be rotatable around a pivot shaft 9 of the scraping cart 5.

  The wire 6 as a traction tool is supported by a plurality of (six in the illustrated example) rotatable pulleys 21, 22, 23, 24, 25, and 26. A part of the wire 6 is fixed to a scraping plate 7 of the scraping cart 5. Further, the wire 6 is wound around two reels 16 and 17 for feeding and winding the wire 6. These two reels 16 and 17 are attached to a drive shaft 51 connected to the motor 15.

  The wire 6 is stretched over pulleys 21, 22, 23, 24, 25, and 26. The pulleys 21 and 26 guide the wire 6 extending from the reels 16 and 17 into the settling tank 1, and the pulleys 22, 23, 24 and 25 transfer the wire 6 extending downward from the pulleys 21 and 26 to the settling tank 1. Guide horizontally along the longitudinal direction. In the illustrated example, the wire 6 is used as a towing tool for towing the scraping cart 5, but a chain can be used instead of the wire 6.

  One end of the wire 6 is wound around one of the two reels 16 and 17 in a right-handed manner, and the other end of the wire 6 is wound around the other of the two reels 16 and 17 in a left-handed manner. The motor 15 is configured to be able to rotate these reels 16 and 17 in forward and reverse directions. When the motor 15 is rotated in the forward direction, the reel 16 winds the wire 6 while the reel 17 feeds the wire 6, and as a result, the scraping cart 5 is pulled toward the pit 10. When the motor 15 is rotated in the reverse direction, the reel 16 feeds the wire 6 while the reel 17 winds the wire 6, and as a result, the scraping cart 5 is pulled away from the pit 10. In this way, the scraping cart 5 can reciprocate on the guide rails 12 and 12 by rotating the motor 15 in the forward direction and the reverse direction.

  FIG. 3 is a schematic side view showing a state where the scraping cart in the sediment scraper shown in FIGS. 1 and 2 scrapes the sediment into the pit. The scraping cart 5 is provided with a stopper 8. As shown in FIG. 3, when the scraping cart 5 is pulled toward the pit 10 by the wire 6, the scraping plate 7 connected to the wire 6 rotates around the pivot shaft 9 until it contacts the stopper 8. Is done. When the scraping plate 7 comes into contact with the stopper 8, the scraping plate 7 assumes a vertical posture. In this state, when the scraping cart 5 is moved toward the pit 10, the scraping plate 7 scrapes the sediment deposited on the bottom surface of the sedimentation tank 1 to the pit 10.

  FIG. 4 is a schematic side view showing a state where the scraping carriage in the sediment scraper shown in FIGS. 1 and 2 is traveling in a direction away from the pit. As shown in FIG. 4, when the scraping carriage 5 is pulled away from the pit 10 by the wire 6, the scraping plate 7 connected to the wire 6 rotates around the pivot shaft 9 in the direction away from the stopper 8. Is done. At this time, the scraping plate 7 is pulled by the wire 6 and converted from a vertical posture to a horizontal posture. As a result, a gap is generated between the scraping plate 7 and the bottom surface of the sedimentation tank 1, and the sediment is prevented from being collected on the side opposite to the pit 10.

  In the sediment scraping machine 3 of the present embodiment, as shown in FIGS. 1 and 2, a plurality of (four in the illustrated example) position detectors 31, 32, 33 that detect the position of the scraping carriage 5. , 34 are arranged along the traveling direction of the scraping cart 5. The sedimentation tank 1 is divided into area 1, area 2, and area 3 along the traveling direction of the scraping cart 5 by the position detectors 31, 32, 33, 34. In the illustrated embodiment, four position detectors are provided. However, in the present invention, at least three position detectors may be provided. When there are three position detectors, the sedimentation tank 1 is provided in two areas. Divided.

  Of the four position detectors 31, 32, 33, 34, two position detectors 31, 34 are arranged on the wall where the liquid inlet 2 of the sedimentation tank 1 is formed and on the opposite side of this wall. Located adjacent to the wall. The position detector 34 is disposed above the pit 10. Therefore, the position detector 34 is a position detector for detecting whether or not the scraping cart 5 has reached a predetermined deposit input position above the pit 10. This deposit input position is a position at which the scraper trolley 5 throws the deposit scraped by the scraper plate 7 into the pit 10.

  The other three position detectors 31, 32, and 33 are position detectors for detecting whether or not the scraping cart 5 has reached three predetermined reverse positions. Each reversing position is a position where the scraping cart 5 traveling in a direction away from the pit 10 reverses the traveling direction. The deposit input position corresponds to the installation position of the position detector 34, and the plurality of inversion positions correspond to the installation positions of the position detectors 31, 32, 33. As can be seen from FIGS. 1 and 2, the deposit input position and the plurality of inversion positions are arranged along the traveling direction of the scraping cart 5.

  The sediment scraper 3 further includes a control unit 38 that controls the travel of the scraping cart 5 based on the position of the scraping cart 5 detected by the position detectors 31, 32, 33, and 34. The control unit 38 makes the scraping cart 5 have at least one scraping process in which the scraping cart 5 reciprocates between the deposit input position and any one selected in advance from the plurality of inversion positions. Configured to run once. For example, when the position detector 34 detects that the scraping cart 5 has reached the deposit input position, the controller 38 reverses the traveling direction of the scraping cart 5 by reversing the motor 15. Further, when the position detector 31 detects that the scraping cart 5 traveling in the direction away from the pit 10 has reached the pre-selected reversal position, the control unit 38 reverses the motor 15 and scrapes the cart. The direction of travel of 5 is reversed.

  The controller 38 is programmed in advance at which reversal position the traveling direction of the scraping cart 5 is reversed. The control unit 38 controls the forward / reverse rotation direction of the motor 15 so that the scraping cart 5 reverses its traveling direction at a preselected reversal position. For example, the scraping cart 5 reciprocates between the deposit input position (that is, the installation position of the position detector 34) and the first reversal position farthest from the pit 10 (that is, the installation position of the position detector 31). A second scraping step in which the one scraping step is performed at least once, and after the first scraping step, reciprocates between the deposit input position and the second inversion position (that is, the position where the position detector 32 is installed). Is carried out at least once, and after the second scraping step, the third reciprocating between the deposit input position and the third reverse position closest to the pit 10 (that is, the position where the position detector 33 is installed). The scraping process is performed at least once. The order and the reverse position of such a scraping process are determined according to an operation recipe set in advance in the control unit 38.

  Next, a specific example of the traveling operation of the scraping cart 5 will be described with reference to FIGS. 5 and 6 are schematic views showing a conventional scraping process, and FIGS. 7 and 8 are schematic views showing the scraping process of the present embodiment. Area 3 is closest to liquid inlet 2, area 1 is furthest from liquid inlet 2, and area 2 is located between area 1 and area 3. Accordingly, as shown in FIGS. 5 to 8, the amount of precipitate in area 2 is larger than the amount of precipitate in area 1, and the amount of precipitate in area 3 is the amount of precipitate in area 2. More than the amount of things. 5 to 8, the amount of the precipitate is schematically expressed.

  In the conventional scraping process shown in FIGS. 5 and 6, the scraping carriage 5 simply travels back and forth between one end and the other end of the sedimentation tank 1. That is, in step 1, the scraping cart 5 moves across the area 1, the area 2, and the area 3 in this order, and scrapes the sediment to the pit 10. Thereafter, in step 2, the area 3, area 2, and area 1 are moved across in this order, and in step 3, the area 1, area 2, and area 3 are moved in this order to deposit the deposit into the pit 10. Rake. In step 3, there is no deposit in the area 1, and the scraping cart 5 travels in the area 1 in vain.

  In step 4, area 3, area 2, and area 1 are moved across in this order, and in step 5, area 1, area 2, and area 3 are moved across in this order to scrape the sediment to pit 10. . Even in this step 5, there is no deposit in the area 1, and the scraping cart 5 travels in the area 1 wastefully. Further, in step 6, the area 3, area 2, and area 1 are moved across in this order, and in step 7, the area 1, area 2, and area 3 are moved in this order to scrape the sediment to the pit 10. . In step 7, there is no deposit in the areas 1 and 2, and the scraping cart 5 travels in the areas 1 and 2 in vain.

  Further, from step 8 to step 11, the scraping cart 5 reciprocates from one end to the other end of the sedimentation tank 1 until all the sediment in the area 3 is discharged into the pit 10. In the final step 12, the scraping cart 5 is returned to the initial position in the area 1. Thus, in the conventional scraping process, the scraping cart 5 travels to an area where the deposit to be scraped does not accumulate, and the scraping cart 5 travels a distance of 36 areas in total. Will be.

  On the other hand, in the scraping process of the present embodiment shown in FIGS. 7 and 8, the scraping cart 5 reciprocates according to the operation recipe programmed in advance in the control unit 38. Specifically, in Step 1, the scraping cart 5 moves across the area 1, the area 2, and the area 3 in this order, and scrapes the deposit to the pit 10. Thereafter, in step 2, the scraping cart 5 moves across the area 3 and the area 2 in this order. That is, the scraping cart 5 reverses its traveling direction at the reverse position corresponding to the installation position of the position detector 32. Therefore, in this step 2, the scraping cart 5 does not travel in the area 1.

  In step 3, the scraping cart 5 moves across the area 2 and the area 3 in this order, and scrapes the sediment to the pit 10. In step 4, the scraping cart 5 moves across the area 3 and the area 2 in this order, and the scraping cart 5 reverses its traveling direction at the reversal position corresponding to the installation position of the position detector 32. In step 5, the scraping cart 5 moves across the area 2 and the area 3 in this order, and scrapes the sediment to the pit 10. Next, in step 6, the scraping cart 5 moves across only the area 3, and the scraping cart 5 reverses its traveling direction at the reversal position corresponding to the installation position of the position detector 33. Thereafter, in step 7, the scraping cart 5 moves across the area 3 and scrapes the deposit into the pit 10. Further, from step 8 to step 11, the scraping cart 5 repeats reciprocating travel within the area 3 until all the sediment within the area 3 is discharged into the pit 10. In the final step 12, the scraping cart 5 is returned to the initial position in the area 1.

  According to such a scraping method, the scraping cart 5 does not travel in an area where deposits to be scraped are not deposited, and the scraping cart 5 has a total travel distance of 20 areas. I will run. That is, by the position detection by the position detectors 32 and 33 and the reversing operation of the scraping cart 5, the scraping cart 5 can execute partial scraping of the sedimentation tank 1. As a result, the scraping cart 5 does not move unnecessarily, which saves energy and extends the life of consumable parts. In the illustrated example, the scraping cart 5 travels only the travel distance of 20 areas compared to the conventional travel distance of 36 areas, so the energy for running the scraping cart 5 is reduced by about 45%. Yes.

  The number of position detectors (indicated by reference numerals 31, 32, 33) for determining the reversal position for reversing the scraping cart 5 traveling in the direction away from the pit 10 may be two, or three or more. But you can. The more the number of position detectors, the more detailed the scraping process can be performed. The reverse position of the scraping cart 5 and the corresponding number of reciprocations are determined in advance based on the amount of sediment in the sedimentation tank 1 and set in the control unit 38 in advance.

  In order to prevent the scraping cart 5 from colliding with the wall of the sedimentation tank 1, the installation positions of the position detectors 31 and 34 are preferably fixed, but on the other hand, the arrangement positions of the position detectors 32 and 33 are changed. It is preferable to make it possible. If the position of the position detectors 32 and 33 can be changed, the reversing position of the traveling trolley 5 can be changed according to the sedimentation state that has changed due to seasonal fluctuations or temporary heavy rain. It can be easily changed.

  Various types of devices can be used as the above-described position detector (represented by reference numerals 31, 32, 33, and 34). For example, the position detector may be a contact-type position detector that includes a striker attached to the scraping carriage 5 and a detection rod that comes into contact with the striker. The detection bar is tilted when the striker comes into contact, and the tilted detection bar generates an electrical signal when the switch is pressed.

  As the position detector, a non-contact type proximity sensor that detects the proximity of the scraping cart 5 by an electrical signal can also be used. In this specification, the proximity sensor is a general term for non-contact sensors that can detect the position of the scraping cart 5 without contacting the detection target, that is, the scraping cart 5. As a detection method in the proximity sensor, a method that uses an eddy current generated in a metal body by electromagnetic induction, a method that captures a change in electric capacity due to the approach of the scraping cart 5, and a magnet that is excited by the approach of the scraping cart 5 There are methods that use. In addition to these, a proximity sensor may be configured by a light projecting unit that emits light upward from the bottom surface of the sedimentation tank 1 and a light receiving unit that receives light from the light projecting unit. In this case, when the scraping cart 5 blocks light from the light projecting unit, the light receiving unit can detect the position of the scraping cart 5. You may comprise a proximity sensor with an ultrasonic transmitter and an ultrasonic receiver.

  When the traction tool 6 is composed of a chain, the position detector may be a contact-type position detector including a striker attached to the chain and a detection rod that comes into contact with the striker. The detection rod tilts when the striker comes into contact, and the tilted detection rod generates an electrical signal when the switch is pressed.

  When the traction tool 6 is configured as a wire as shown in the drawing, the position detector may be a traveling position detector that detects the position of the scraping carriage 5 from the feed amount of the wire 6. For example, the travel position detector can feed the wire 6 from the number of rotations of the reel 16 and / or the reel 17 or from the number of rotations of a rotatable pulley (for example, the pulley 21 or the pulley 26) that supports the wire 6. And the position of the scraping cart 5 is detected from this feed amount. In this case, the position detector is not installed in the sedimentation tank 1.

  The scraping cart 5 shown in the figure includes a traveling wheel 13 that travels on the traveling guide rails 12 and 12. In this case, the position detector may be a travel position detector that detects the position of the scraping cart 5 (that is, the travel distance of the scraping cart 5) from the rotation direction and the number of rotations of the travel wheel 13. Also in this case, no position detector is installed in the sedimentation tank 1.

  The position detector may be a weight sensor that detects whether or not the scraping cart 5 is present from a change in weight. The weight sensor is configured to detect a change in weight when the scraping cart 5 is placed on the weight sensor.

  The position detector determines the travel distance of the scraping cart 5, that is, the position of the scraping cart 5 from the timer that measures the travel time of the scraping cart 5, the measured travel time and the travel speed of the scraping cart 5. And a position determining unit. Also in this case, no position detector is installed in the sedimentation tank 1.

  FIG. 9 is a schematic side view showing an embodiment in which an inclined plate is attached to the settling tank. FIG. 10 is a schematic side view of the settling tank shown in FIG. 9 as viewed from the liquid inlet side of the settling tank. In the lower part of FIG. 10, a schematic diagram of the scraping carriage 5 in which the scraping plate 7 is in a vertical posture is drawn. As shown in FIGS. 9 and 10, a plurality of inclined plates 40 are provided in the area 3 and the area 2 of the settling tank 1. When such an inclined plate 40 is provided, impurities (precipitates) contained in the flowing liquid come into contact with the inclined plate 40, so that in the area 3 and the area 2, to the bottom surface of the impurity precipitation tank 1. Settling is promoted. As a result, more sediment is deposited in area 3 and area 2, and almost no sediment is generated in area 1.

  In such a sedimentation tank 1, in the area 1 where the inclined plate 40 is not provided, the number of travels of the scraping cart 5 is reduced. As a result, the travel distance of the scraping cart 5 can be further shortened, and energy saving can be achieved.

  Next, another embodiment of the present invention will be described. FIG. 11 is a schematic plan view of a sediment scraper according to another embodiment of the present invention. Since the configuration and operation of the present embodiment that are not particularly described are the same as those of the above-described embodiment, redundant description thereof is omitted.

  As shown in FIG. 11, the sediment scraping machine of the present embodiment includes a scraping cart 5 that scrapes the sediment deposited on the bottom surface of the sedimentation tank 1 to a pit 10 provided on the bottom surface of the sedimentation tank 1, and a sediment A driving device 50 that causes the scraping cart 5 to travel on the bottom surface of the tank 1, a speed reduction device 53 that is coupled to the drive shaft 51 of the driving device 50, a moving mechanism 55 that is coupled to the speed reduction device 53, and the scraping cart 5 The position indicator 56 is provided that is moved by the moving mechanism 55 at a speed slower than that of the scraping carriage 5 in synchronization with the traveling of the vehicle. The position indicator 56 and the moving mechanism 55 are disposed outside the sedimentation basin 1.

  The drive device 50 includes a motor 15, a drive shaft 51 connected to the motor 15, reels 16 and 17 fixed to the drive shaft 51, pulleys 21 to 26, and a wire 6 as a traction tool. Similarly to the above-described embodiment, when the motor 15 is driven, the wire 6 is pulled, and the scraping cart 5 connected to the wire 6 travels on the bottom surface of the sedimentation tank 1.

  The reduction gear 53 includes a reduction gear, a chain and a sprocket, a belt and a pulley. In this embodiment, the input shaft 53a of the speed reduction device 53 is directly connected to the drive shaft 51 of the drive device 50, but may be indirectly connected to the drive shaft 51 via a power transmission device such as a gear. . The reduction device 53 is a device that reduces the rotational speed of the drive shaft 51, and therefore the output shaft 53 b of the reduction device 53 rotates at a lower rotational speed than the drive shaft 51. For example, the rotational speed of the drive shaft 51 is reduced to 1/100. In this case, the reduction ratio of the output shaft 53b to the input shaft 53a of the reduction gear 53 is 1/100. However, the reduction ratio of the reduction gear 53 is not limited to 1/100, and is appropriately selected.

  The reduction gear 53 is connected to the moving mechanism 55. The moving mechanism 55 includes a rotating shaft 58 connected to the output shaft 53 b of the speed reducer 53, two reels 60 and 61 fixed to the rotating shaft 58, and a traction tool wound around these reels 60 and 61. Wire 63 and two pulleys 65 and 66 for supporting the wire 63. The position indicator 56 is attached to the wire 63. The mechanism by which the moving mechanism 55 moves the position indicator 56 is the same as the mechanism by which the driving device 50 travels the scraping cart 5. That is, when the rotary shaft 58 rotates in one direction, the reel 60 takes up the wire 63, while the reel 61 feeds out the wire 63. As a result, the position indicator 56 is moved in one direction. When the rotating shaft 58 rotates in the reverse direction, the reel 60 unwinds the wire 63 while the reel 61 winds up the wire 63. As a result, the position indicator 56 is moved in the reverse direction.

  FIG. 12 is a diagram illustrating another configuration example of the moving mechanism 55. In this example, the moving mechanism 55 includes a rotary shaft 58 connected to the output shaft 53b of the speed reducer 53, a drive sprocket 67 fixed to the rotary shaft 58, and a driven sprocket rotatably supported by a support shaft (not shown). 68 and a chain 69 as a traction tool spanned over the drive sprocket 67 and the driven sprocket 68. The position indicator 56 is attached to the chain 69. When the rotating shaft 58 rotates in one direction, the drive sprocket 67 and the driven sprocket 68 rotate and the chain 69 circulates in one direction. As a result, the position indicator 56 is moved in one direction. When the rotating shaft 58 rotates in the reverse direction, the drive sprocket 67 and the driven sprocket 68 rotate and the chain 69 circulates in the reverse direction. As a result, the position indicator 56 is moved in the reverse direction.

  The rotary shaft 58 is rotated in the same direction as the drive shaft 51. Since the rotation speed of the rotation shaft 58 is lower than the rotation speed of the drive shaft 51, the position indicator 56 moves in synchronization with the traveling of the scraping carriage 5 and at a slower speed than the scraping carriage 5. Therefore, the movement width of the position indicator 56 is shorter than the movement width of the scraping carriage 5. For example, when the movement width of the scraping carriage 5 is 40 m and the reduction ratio of the reduction gear 53 is 1/100, the movement width of the position indicator 56 is 40 cm.

  The sediment scraping machine includes two position detectors 71 and 72 for detecting the position of the position indicator 56, and a control unit 38 for reversing the traveling direction of the scraping carriage 5 based on the position of the position indicator 56. I have. The position detectors 71 and 72 are connected to the control unit 38, and the position detection signals output from the position detectors 71 and 72 are transmitted to the control unit 38. The position detectors 71 and 72 are disposed adjacent to the position indicator 56. The position detectors 71 and 72 may be contact type position sensors or non-contact type position sensors. Only one position detector may be arranged, or three or more position detectors may be arranged.

  The position detector 71 is a position detector for detecting whether or not the scraping cart 5 has reached a predetermined reverse position. This reversal position is a position where the scraping cart 5 traveling toward the pit 10 reverses its traveling direction. The position detector 72 is also a position detector for detecting whether or not the scraping cart 5 has reached a predetermined reverse position. This reversal position is a position where the scraping cart 5 traveling in a direction away from the pit 10 reverses the traveling direction.

  Since the position indicator 56 moves in synchronization with the traveling of the scraping carriage 5, the control unit 38 detects the position of the scraping carriage 5 based on the position of the position indicator 56 and further travels the scraping carriage 5. Can be controlled. Specifically, when the position indicator 56 is detected by the position detector 71, that is, when the position detector 71 detects that the position indicator 56 has reached a position corresponding to the predetermined reverse position, the control is performed. The part 38 reverses the traveling direction of the scraping cart 5. Similarly, when the position indicator 56 is detected by the position detector 72, that is, when the position detector 72 detects that the position indicator 56 has reached a position corresponding to the predetermined reverse position, the control unit 38. Reverses the traveling direction of the scraping cart 5.

  Similar to the above-described embodiment, the operation of the scraping cart 5 is executed according to an operation recipe set in advance in the control unit 38. Of course, it is possible to carry out a scraping process as shown in FIGS. 7 and 8 by installing three or more position detectors.

  Since the position indicator 56 is disposed outside the sedimentation basin 1, it is not necessary to dispose a position detector in the sedimentation basin 1. Therefore, the position detector can be easily installed and the installation position can be easily changed. Further, it is not necessary to use a waterproof position detector as the position detector, and there is no risk of the position detector failing due to water immersion. Furthermore, since the movement width of the position indicator 56 is smaller than the travel width of the scraping cart 5, the wiring cost of the position detectors 71 and 72 can be reduced.

  As shown in FIG. 11, a stopper 75 for stopping the scraping cart 5 at an initial position (standby position) in the sedimentation basin 1 is disposed in the sedimentation basin 1. The scraping cart 5 that has finished the sediment scraping step is returned to the initial position. At this time, when the scraping cart 5 collides with the stopper 75, the load on the motor 15 increases, and as a result, the current flowing through the motor 15 increases. The control unit 38 can detect that the scraping cart 5 has collided with the stopper 75, that is, that the scraping cart 5 has returned to the initial position by detecting the increase in current. Therefore, a position detector for detecting that the scraping cart 5 has returned to the initial position is unnecessary.

  Since a large load is applied to the wire 6 that pulls the scraping cart 5, the wire 6 may be stretched. When the wire 6 extends, the position indicator 56 does not correspond to the position of the scraping carriage 5. Therefore, in order to detect the actual position of the scraping cart 5, it is preferable to install at least one position detector 34 in the sedimentation basin 1 as shown in FIG. The position detector 34 may be a contact type position sensor or a non-contact type position sensor.

  FIG. 13 is a view showing an embodiment in which the inclined plate 40 shown in FIGS. 9 and 10 is incorporated in the embodiment shown in FIG. The scraping cart 5 travels under the inclined plate 40 and scrapes the deposit on the bottom surface of the sedimentation basin 1 to the pit 10. In order to efficiently transfer the sediment on the bottom surface of the sedimentation basin 1 to the pit 10, the position where the traveling direction of the scraping cart 5 is reversed is between the lower position of the inclined plate 40 and the upper position of the pit 10. It is preferable. Therefore, the installation position of the position detector 71 shown in FIG. 11, that is, the position of the position indicator 56 detected by the position detector 71 is scraped between the lower position of the inclined plate 40 and the upper position of the pit 10. A position corresponding to the reversal position of the carriage 5 is preferable.

  FIG. 14 is a view showing an embodiment in which settling plates 80 and 81 are incorporated in the embodiment shown in FIG. The sedimentation plates 80 and 81 have the same function as the inclined plate 40 shown in FIGS. 9 and 10, and have a function of promoting precipitation of impurities (precipitates) contained in the liquid. However, the sedimentation plates 80 and 81 differ from the above-described tilt plate 40 in that the tilt angle is variably configured. As shown in FIG. 14, the sedimentation plates 80 and 81 are connected to an inclination mechanism 79, and the sedimentation plates 80 and 8 can be inclined at a desired angle by the inclination mechanism 79.

  15 is a cross-sectional view taken along line AA shown in FIG. In the sedimentation basin 1, a plurality of (seven in the illustrated example) sedimentation plates 80 and 81 are arranged. The settling plates 80 and 81 are composed of a group consisting of odd-numbered settling plates 80 located in odd-numbered stages and a group consisting of even-numbered settling plates 81 located in even-numbered stages. The settling plate located at the top is the first settling plate, that is, the odd settling plate 80. The odd-numbered settling plates 80 and the even-numbered settling plates 81 are alternately arranged at predetermined intervals along the vertical direction. The sedimentation plates 80 and 81 each have a rectangular shape. The settling plates 80 and 81 are arranged in a plurality of rows (four rows in the illustrated example) in the horizontal direction. The settling plates 80 and 81 are rotatably supported by a support mechanism 85 fixed to a rectangular frame 83.

  FIG. 16 is a perspective view showing a row of sedimentation plates 80 and 81 arranged along the vertical direction. As shown in FIGS. 15 and 16, the settling plates 80 and 81 are rotatably supported by two support mechanisms 85 arranged on both sides of the settling plates 80 and 81. These support mechanisms 85 rotatably connect two support rods 86 extending in the vertical direction on both sides of the settling plates 80 and 81, and the center portions of the short sides of the settling plates 80 and 81 and the two support rods 86. And a central joint 87. Both ends of the support rod 86 are fixed to the frame 83. The center joint 87 allows the settling plates 80 and 81 to rotate about a rotation axis extending horizontally.

  As shown in FIG. 15, the plurality of rows of sedimentation plates 80 and 81 are connected to the frame 83 via a plurality of support mechanisms 85 to constitute one sedimentation plate unit. In FIG. 14, one settling plate unit is arranged in the settling tank 1, but two or more settling plate units may be arranged.

  On both sides of the settling plates 80 and 81, an odd-numbered link mechanism 90 and an even-numbered link mechanism 93 are provided. The odd-stage link mechanism 90 is connected to both short sides of the odd-stage settling plate 80, and the even-stage link mechanism 93 is connected to both short sides of the even-stage settling plate 81.

  The odd-stage link mechanism 90 includes two odd-stage rods 101 that are arranged on both sides of the odd-stage sedimentation plate 80 and extend in the vertical direction, and these two odd-stage rods 101 are connected to the ends of both short sides of the odd-stage sedimentation plate 80. And an odd-numbered joint 102 that is rotatably connected to the portion. The odd-numbered joint 102 allows the odd-numbered settling plate 80 to rotate relative to the odd-numbered rod 101.

  The even-stage link mechanism 93 includes two even-stage rods 104 that are arranged on both sides of the even-stage sedimentation plate 81 and extend in the vertical direction, and the two even-stage rods 104 are connected to the ends of both short sides of the even-stage sedimentation plate 81. And an even-numbered joint 105 that is rotatably connected to the portion. The even-stage joint 105 allows the even-stage settling plate 81 to rotate relative to the even-stage rod 104.

  An odd-stage actuator 110 for operating the odd-stage link mechanism 90 is connected to the odd-stage link mechanism 90. When the odd-stage actuator 110 operates the odd-stage link mechanism 90, the plurality of odd-stage settling plates 80 are inclined simultaneously. Similarly, an even stage actuator 111 for operating the even stage link mechanism 93 is connected to the even stage link mechanism 93. When the even-stage actuator 111 operates the even-stage link mechanism 93, the plurality of even-stage settling plates 81 are simultaneously inclined. In the present embodiment, the tilting mechanism 79 that tilts the settling plates 80 and 81 includes at least an odd-numbered stage link mechanism 90, an even-numbered stage link mechanism 93, an odd-numbered stage actuator 110, and an even-numbered stage actuator 111.

  In the present embodiment, the odd-stage actuator 110 and the even-stage actuator 111 are configured as air cylinders for operating the odd-stage link mechanism 90 and the even-stage link mechanism 93, respectively. Hereinafter, the odd-stage actuator 110 and the even-stage actuator 111 may be referred to as the odd-stage air cylinder 110 and the even-stage air cylinder 111, respectively.

  The odd-stage air cylinder 110 and the even-stage air cylinder 111 are connected to the compressed air storage tank 120 and operate with the compressed air stored in the compressed air storage tank 120. A compressor 121 is connected to the compressed air storage tank 120.

  Next, the inclination operation of the odd-numbered settling plate 80 and the even-numbered settling plate 81 will be described with reference to FIGS. FIG. 17 is a view of the sedimentation plates 80 and 81 in the horizontal state as viewed from the sedimentation plate short side. FIG. 18 is a diagram showing a state in which only the odd-stage sedimentation plate 80 is inclined. FIG. 19 is a view showing a state in which only the even-stage sedimentation plate 81 is inclined. 17 to 19 show only one row of sedimentation plates 80 and 81 among a plurality of rows.

  As shown in FIG. 17, when the sedimentation plates 80 and 81 are in a horizontal state, the sedimentation area is maximized. The initial state of the sedimentation plates 80 and 81 is a horizontal state, and deposits accumulate on the upper surfaces of the sedimentation plates 80 and 81 in the initial state. The upper surfaces of the settling plates 80 and 81 constitute the settling surfaces 80a and 81a of the settling plates 80 and 81.

  When a predetermined time elapses after the liquid to be treated is introduced into the sedimentation basin 1 through the liquid inlet 2, only the odd-numbered sedimentation plate 80 is first inclined to slide down the sediment on the odd-numbered sedimentation plate 80. It moves to the sedimentation surface 81a of the stage sedimentation plate 81 and the bottom of the sedimentation basin 1. A state in which only the odd-stage sedimentation plate 80 is inclined is shown in FIG. FIG. 18 shows a state where one row of odd-stage sedimentation plates 80 is inclined, but a plurality of rows of odd-stage sedimentation plates 80 are simultaneously inclined.

  The state where only the odd-stage sedimentation plate 80 is inclined is achieved by operating the odd-stage actuator 110. The center portion of the odd-numbered settling plate 80 is rotatably supported by the center joint 87 of the support mechanism 85, and the support mechanism 85 is fixed to the frame 83. Therefore, when the odd-numbered stage link mechanism 90 is moved downward by the odd-numbered stage actuator 110, the odd-numbered stage sedimentation plate 80 rotates around the central joint 87, and only the odd-numbered stage sedimentation plate 80 is inclined as shown in FIG. Can be made.

  If the sediment can slide down on the sedimentation surface 80a, the inclination angle of the odd-numbered sedimentation plate 80 is not particularly limited. In order to ensure that the sediment slides down, the inclination angle of the odd-stage sedimentation plate 80 is preferably approximately 90 ° with respect to the horizontal direction as shown in FIG. The inclination angle of the odd-stage sedimentation plate 80 can be changed by adjusting the operating distance (stroke) of the air cylinder configured as the odd-stage actuator 110.

  After the odd-stage sedimentation plates 80 are tilted, the odd-stage sedimentation plates 80 are returned to the initial horizontal state. Specifically, the odd-stage actuator 110 is operated to move the odd-stage link mechanism 90 upward. Also in this case, as described above, the odd-stage sedimentation plate 80 rotates around the central joint 87. As a result, as shown in FIG. 17, all of the odd-numbered settling plates 80 and the even-numbered settling plates 81 are in a horizontal state.

  Subsequently, only the even-stage sedimentation plate 81 is inclined. FIG. 19 shows a state where only the even-stage sedimentation plate 81 is inclined. The state in which only the even-stage sedimentation plate 81 is inclined is achieved by operating the even-stage actuator 111. A central portion of the even-stage sedimentation plate 81 is rotatably supported by a central joint 87 of the support mechanism 85, and the support mechanism 85 is fixed to the frame 83. Accordingly, when the even-stage link mechanism 93 is moved upward by the even-stage actuator 111, the even-stage settling plate 81 rotates around the central joint 87, and only the even-stage settling plate 81 is inclined as shown in FIG. Can be made.

  If the sediment can slide down on the sedimentation surface 81a, the inclination angle of the even-stage sedimentation plate 81 is not particularly limited. In order to surely slide down the sediment, the inclination angle of the even-stage sedimentation plate 81 is preferably approximately 90 ° with respect to the horizontal direction as shown in FIG. The inclination angle of the even-stage sedimentation plate 81 can be changed by adjusting the operating distance (stroke) of the air cylinder configured as the even-stage actuator 111.

  After the even-stage sedimentation plates 81 are tilted, the even-stage sedimentation plates 81 are returned to the horizontal state. Specifically, the even-stage actuator 111 moves the even-stage link mechanism 93 downward. Also in this case, as described above, the even-stage sedimentation plate 81 rotates around the central joint 87. As a result, as shown in FIG. 17, all of the odd-numbered settling plates 80 and the even-numbered settling plates 81 are in a horizontal state.

  As described above, the odd-numbered settling plates 80 and the even-numbered settling plates 81 are alternately inclined. In order to move the sediment deposited on the odd-numbered sedimentation plate 80 positioned at the top to the bottom of the sedimentation basin 1, the tilting operation of the odd-numbered sedimentation plate 80 and the even-numbered sedimentation plate 81 is repeated. In the illustrated example, the odd-numbered settling plate 80 and the even-numbered settling plate 81 are inclined seven times in total. Specifically, the odd-numbered settling plate 80 is tilted four times, and the even-numbered settling plate 81 is tilted three times. That is, assuming that the settling plates 80 and 81 are arranged in n stages in total, the tilting operation of the odd settling plate 80 and the even settling plate 81 is performed n times in total.

  In this manner, since the odd-numbered settling plates 80 and the even-numbered settling plates 81 are alternately and alternately inclined, the settling plates 80 and 81 adjacent in the vertical direction are not simultaneously inclined. Therefore, it is possible to reduce the distance that the precipitate falls. As a result, the fallen deposit is prevented from being destroyed. In addition, when the sediment is slid down, either the odd-stage sedimentation plate 80 or the even-stage sedimentation plate 81 remains in a horizontal state, so that the sediment is effectively prevented from rising in the sedimentation basin 1. can do. Furthermore, since only one of the odd-stage sedimentation plate 80 and the even-stage sedimentation plate 81 is inclined, the sedimentation promoting function of the sediment in the sedimentation basin 1 can be maintained.

  In the present embodiment, the odd-stage sedimentation plate 80 and the even-stage sedimentation plate 81 have auxiliary sedimentation plates 122 extending perpendicularly to the sedimentation surfaces 80a and 81a of the sedimentation plates 80 and 81. The auxiliary sedimentation plate 122 extends downward from the odd-stage sedimentation plate 80 and the even-stage sedimentation plate 81 so as not to prevent sedimentation on the sedimentation surfaces 80a and 81a.

  The auxiliary sedimentation plate 122 has an auxiliary sedimentation surface 122a on which sediment contained in the liquid to be treated can be deposited when the sedimentation plates 80 and 81 are inclined (see FIGS. 18 and 19). The area of each auxiliary sedimentation surface 122a is preferably 1/5 or more of the area of each of the sedimentation surfaces 80a and 81a. If the auxiliary sedimentation plate 122 is provided in this way, even if either the odd-numbered sedimentation plate 80 or the even-numbered sedimentation plate 81 is inclined, the effective sedimentation area for sedimenting the sediment is set to the auxiliary sedimentation surface 122a. Can be ensured by.

  In order to maintain the settling plate device or to clean the inside of the settling basin 1, water may be drained to drain all the liquid to be treated in the settling basin 1. In this case, no problem occurs even if the sediment rises in the sedimentation basin 1, and therefore, the odd-stage sedimentation plate 80 and the even-stage sedimentation plate 81 may be inclined at the same time.

  The operation of the tilt mechanism 79 that tilts the settling plates 80 and 81 is controlled by the control unit 38. As a result of the inclination of the sedimentation plates 80 and 81, all the sediment deposited on the sedimentation plates 80 and 81 moves to the bottom surface of the sedimentation basin 1, and then the scraping cart 5 shown in FIG. And drive the sediment to the pit 10. In order to efficiently transfer the sediment on the bottom surface of the sedimentation basin 1 to the pit 10, the position where the traveling direction of the scraping cart 5 is reversed is between the lower position of the sedimentation plates 80 and 81 and the upper position of the pit 10. It is preferable that it exists in. Therefore, the position of the position detector 71 shown in FIG. 11, that is, the position of the position indicator 56 detected by the position detector 71 is between the lower position of the settling plates 80 and 81 and the upper position of the pit 10. A position corresponding to the reverse position of the scraping cart 5 is preferable.

  The preferred embodiments of the sediment scraper have been described so far, but when a plurality of sedimentation tanks 1 as shown in the figure are provided in parallel, a plurality of sediment scrapers are provided in the plurality of sedimentation tanks 1. 3 can be provided. When the size of the sedimentation tank 1 is large, a plurality of sediment scraping machines 3 can be arranged in one sedimentation tank 1.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible.

DESCRIPTION OF SYMBOLS 1 Sedimentation tank 2 Liquid inlet 3 Sediment scraping machine 5 Scraping cart 6 Pulling tool 7 Scraping plate 9 Pivot shaft 10 Pit 12 Guide rail 15 Motor 16 Reel 17 Reel 21-26 Pulley 31-34 Position detector 38 Control Numeral 40 Inclined plate 50 Drive device 51 Drive shaft 53 Deceleration device 55 Movement mechanism 56 Position indicator 58 Rotating shaft 60, 61 Reel 63 Wire 65, 66 Pulley 67 Drive sprocket 68 Drive sprocket 69 Chain 71, 72 Position detector 75 Stopper 80 , 81 Settling plate 79 Inclination mechanism 90 Odd stage link mechanism 93 Even stage link mechanism 110 Odd stage actuator 111 Even stage actuator

Claims (6)

A scraping cart that scrapes the sediment deposited on the bottom surface of the sedimentation tank to a pit provided on the bottom surface of the sedimentation tank;
A drive device for running the scraping carriage on the bottom surface of the settling tank;
A speed reducer coupled to the drive shaft of the drive device and decelerating the rotational speed of the drive shaft;
A moving mechanism coupled to the speed reducer;
A position indicator that is moved by the moving mechanism in synchronization with the running of the scraping carriage and at a slower speed than the scraping carriage;
A position detector for detecting the position of the position indicator;
A sediment scraping machine comprising: a control unit that reverses a traveling direction of the scraping carriage based on a position of the position indicator. The sediment scraper according to claim 1 , wherein the position indicator is disposed outside the sedimentation tank. An inclined plate is disposed in the settling tank,
Position for reversing the running direction of the scraper carriage, sediment scraper machine according to claim 1 or 2, characterized in that between the upper position of the low position of the inclined plate pit. A settling plate disposed in the settling tank;
An inclination mechanism for inclining the sedimentation plate,
After said tilting mechanism is tilted the settling plate, said scraper carriage, sediment scraper machine according to claim 1 or 2, characterized in that traveling under the settling plate. Position for reversing the running direction of the scraper carriage, sediment scraper machine according to claim 1, characterized in that between the upper position and lower position of the settling plate the pits.   A sediment scraping method that scrapes the sediment deposited on the bottom surface of the sedimentation tank using a scraping carriage into a pit provided in the sedimentation tank,
  Run the scraping carriage on the bottom surface of the settling tank by a driving device,
  By the speed reducer connected to the drive shaft of the drive device, the rotational speed of the drive shaft is reduced,
  By the movement mechanism connected to the speed reducer, the position indicator is moved in synchronization with the traveling of the scraping carriage and at a slower speed than the scraping carriage,
  Detecting the position of the position indicator with a position detector;
  A sediment scraping method, wherein the traveling direction of the scraping carriage is reversed based on the position of the position indicator.

Images