JP2003039065A - Scum scraping unit in sludge scraper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scum scraping unit in a sludge scraper capable of surely scraping up scum floating over the whole water surface toward a scum skimmer and discharging it by securing sufficient elevating length of the rear end of a scum beam. SOLUTION: This sludge scraper comprises a sludge scraping unit 4 disposed along the tank bottom 11 of a sewage treatment tank 1 for scraping together pieces of sludge on the tank bottom 11 toward a sludge pit P by its elevating and reciprocating movement, a drive unit 5 installed above the water surface so as to hang and support the sludge scraping unit 4 and to move it up and down, and back and forth, and a scum scraping unit 6 driven in conjunction with the sludge scraping unit 4. The scum beam 64 of the scum scraping unit 6, equipped with a scum blade 65, is divided into a front part and a back part. The intermediate part is connected flexibly, and the front scum beam 64A is supported by the sludge scraping unit 4 through struts 62, 63. A scum elevating unit 8 moves the back scum beam 64B upward when the sludge scraping unit 4 moves back, and moves it downward when the sludge scraping unit 4 moves forward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scum scraping device for a sludge scraping machine, and particularly to a sludge scraping device which is capable of reciprocating along a tank bottom to scrape up sludge even in a long wastewater treatment tank. The present invention relates to a scum scraping device in a sludge scraping machine, which is capable of securely scraping floating scum to the full width of the tank until the scum gap is near, in cooperation with the sludge scraping cycle of the scraping machine.

[0002]

2. Description of the Related Art Conventionally, a sludge scraper (including a settling sand scraper intended for sedimentation and simply referred to as "sludge scraper" in the present specification) is generally a sludge settling on one end. An endless chain that moves along the bottom of the tank and the water surface is stretched in a sewage treatment tank that has a sludge pit that collects and temporarily stores the sewage, and scrapers are attached to this chain at predetermined intervals and driven by a drive device. By doing so, the chain is circulated, and the sludge that is in contact with the tank bottom on the outward path scrapes the settled sludge and collects it in the sludge pit, and by the scraper at the water surface on the return side, The scum floating on the surface of the water is scraped up and discharged through the scum gap.

However, in this endless chain type sludge attractor, the endless chain is stretched in the wastewater so as to be circulated and driven. Therefore, the chain and the sprocket wheel for stretching the chain are rotated. The sliding parts are inevitably located in the dirty water, and the rotating sliding parts are worn or corroded due to contact with the dirty water mixed with sludge, etc., and the durability of the device is low. There was a problem that it took time and money.

Therefore, by eliminating the rotary sliding parts in the dirty water, abrasion and corrosion can be prevented and the durability of the apparatus can be improved. A pin rack is provided on a guide rail that is formed in an elliptical shape that is equal to the stroke length of movement, and a drive device that is configured to engage the pin rack and drive a pin wheel that moves along the guide rail by a motor is installed on the water surface. However, when the front part of the sludge attracting device equipped with the scraper is swingably arranged with respect to the rear part and the drive device moves forward in the sludge attracting direction, the front part of the sludge attracting device is moved. When the scraper moves in contact with the tank bottom and moves backward in the opposite direction, the scraper in the front part of the sludge attracting device is configured to move away from the tank bottom, and at least The scraper at the rear part of the mud scraping device is formed so as to scrape the sludge when moving forward in the sludge scraping direction, and to sink into the settled sludge when moving backward in the opposite direction. There has been proposed a sludge scraping machine configured to interlock with a scum scraping device.

However, in the sludge scraper in which the scraper reciprocates along the bottom of the tank, the lifting stroke of the rear part becomes smaller than the front part of the lift beam due to the structure of the lifting beam, and the sludge scraper becomes smaller. The scum scraping device arranged at the upper position of the is integrally formed from its front end to its rear end, and is suspended and supported at its front position, so that it works in conjunction with the sludge scraping device. Even if driven, the whole scum scraping device does not float uniformly, therefore the stroke of the rear end of the scum beam for scum scooping is small, and scum floating on the water surface is evenly scraped over the entire water surface. There was a problem that I could not.

In view of the problems of the above-mentioned conventional sludge scraper, the present invention ensures a sufficient lifting stroke of the rear end of the scum beam so that the scum floating on the entire water surface can be reliably scraped to the scum skimmer side. An object of the present invention is to provide a scum scraping device in a sludge scraping machine that can be discharged.

[0007]

In order to achieve the above object, the scum scraping device in the sludge scraping machine of the present invention is arranged along the bottom of a wastewater treatment tank and moves up and down and reciprocates. A sludge attracting device for scraping sludge on the bottom of the tank toward the sludge pit, a drive device installed on the water surface for suspending and supporting the sludge attracting device to move up and down and reciprocally, and a sludge attracting device A scum scraping device in a sludge scraping machine comprising a scum scraping device adapted to be driven in conjunction with the scum scraping device, wherein a scum beam having a scum blade of the scum scraping device is divided into front and rear parts, and an intermediate part. When the sludge attracting device is moved backward by the scum lifting device, the front scum beam is supported by the sludge attracting device via the stanchions, and when the sludge attracting device moves backward, Characterized in that as drops.

The scum scraping device in this sludge scraper divides a scum beam provided with a scum blade of the scum scraper into front and rear parts, connects the middle part so as to be bendable, and connects the front scum beam to the sludge scraper. Since the rear scum beam is supported by the device and the rear scum beam is raised by the scum lifting device when the sludge attracting device moves backward and descends when moving forward, the sewage treatment tank becomes longer. Even if the scum raking device becomes longer following this, the rear scum beam is forcibly lifted and lowered by the scum lifting device, so that even a long scum raking device can secure a uniform lifting stroke over its entire length, and The scum floating on the water surface of the sewage treatment tank can be reliably scraped and discharged.

In this case, the scum skimmer can be arranged at a position rearward of the support portion of the sludge attracting device.

With this, the scum scraped by the scum scraping device can be surely discharged from the scum skimmer.

In this case, the sewage treatment tank is
There can be multiple layers.

As a result, the installation area of the sewage treatment tank is made small, and the sludge settling on the bottom of each tank and the scum floating on the water surface are simultaneously scraped and discharged by one drive installed on the water surface. can do.

Further, in this case, the scum raising / lowering device can be constructed so that the roller attached to the upper end of the suspension post for suspending and supporting the rear scum beam is movably supported along the inclined guide rail. .

With this, the rear scum beam can be smoothly moved along the guide rail by following the drive of the drive device by the simple scum lifting device, so that the lifting operation can be performed reliably and automatically. It can be carried out.

Further, in this case, the scum elevating device is provided with a guide rail adapted to vertically move the roller attached to the upper end of the suspension post for suspending and supporting the rear scum beam so that the roller is vertically moved during the reciprocating movement. It can be configured to support.

As a result, the upper and lower turning guide rails guide the rollers for raising and lowering mounted on the rear scum beam, so that the rollers can be surely circulated in one direction. The rear scum beam that is suspended and supported can be reliably moved up and down and moved.

Further, in this case, the scum raking device may be constructed so that the rope fastened to the front and rear of the rear scum beam is hung on the moving wheel of the scum lifting device to suspend and support it.

As a result, the structure of the scum attracting device can be simplified and the operation can be performed more reliably.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a scum attracting device in a sludge attracting machine of the present invention will be described below with reference to the drawings.

1 to 8 show a sewage treatment tank 1 such as a long sludge sedimentation basin and a sand basin to which the scum scraping device in the sludge scraper of the present invention is applied.

FIG. 1 shows a multi-tank type sewage treatment tank having a long settling tank on the upper and lower floors, and FIG. 2 shows a single layer type of the long sewage treatment tank 1. In any of these sewage treatment tanks 1, A sludge pit P having a sludge drawing pipe 2 is provided at the bottom of the waste water supply side while introducing the waste water from one end thereof.
The tank bottom 11 in each tank of the sewage treatment tank 1 is preferably inclined so that the sludge pit P side becomes low so that the sewage easily flows into the sludge pit P when cleaning the sewage treatment tank 1. To be formed.

In the sewage treatment tank 1, a scum skimmer K is placed at a position where scum contained in the sewage introduced into the sewage treatment tank 1 is separated and floated, for example, near the center of the sewage treatment tank 1. The scum floating on the water surface is discharged to the outside of the sewage treatment tank 1, and a plurality of outflow gutters 3 are arranged on the water surface behind the scum skimmer K to settle and separate sludge and remove the scum. The latter sewage is configured to be discharged to the outside of the sewage treatment tank 1. The scum skimmer K and the outflow gutter 3 are installed in each layer even in the multi-tank wastewater treatment tank 1.

Further, in the sewage treatment tank 1, sludge scrapers A for scraping the sludge settled at the bottoms 11 of the tanks and collecting the sludge in the sludge pit P are arranged in each of the upper and lower layers. This sludge scraping machine A is a sludge scraping device 4 for scraping sludge settling on the bottom 11 of the waste water treatment tank 1, and a sludge scraping device 4 that suspends and supports the sludge scraping device 4 with a predetermined stroke length. 1. A drive device 5 installed on the water surface that reciprocates along the longitudinal direction of 1 and a sludge scraping device 4 installed in the tank on the top floor are integrally attached above the scum and the scum floating on the water surface is scratched on the scum skimmer K. It is composed of a scum scraping device 6 for pulling.

The sludge attracting device 4 is the bottom 1 of the wastewater treatment tank 1.
1. For example, two sludge attracting beams 41, 41 are arranged in parallel at both end portions in the width direction of the tank bottom 11 over substantially the entire length in the longitudinal direction of the tank bottom 11 excluding the sludge pit P and the stroke length. A plurality of scrapers 42, 42 are installed between the two sludge attracting beams 41, 41.

A sludge scraping beam 41, on which a scraper 42 of the sludge scraping device 4 is installed, is divided into a front part and a rear part, the front part of which is a lifting beam 41A and the rear part of which is a horizontal beam 41B. 41A and horizontal beam 41B
The supporting beams are connected to each other via a supporting portion, whereby the front and rear lifting beams 41A and horizontal beams 41B can be swung by this supporting portion, and the front position of the lifting beam 41A at the front portion is driven via the post 7. The device 5 is suspended and supported. This drive 5
When the sludge attracting device 4 is moved forward in the sludge attracting direction by the drive of, the front part of the elevating beam 41A is substantially horizontal with the rear part of the horizontal beam 41B and is attached to the lower part of the elevating beam 41A in a lowered state. Scraper 42
However, when it moves in contact with the tank bottom 11 to scrape the sludge settling on the tank bottom, and when moving in the reverse direction of the opposite direction,
The elevating beam 41A is lifted by the post 7, and the scraper 42 that is bent from the bent portion and attached to the lower part of the elevating beam 41A moves away from the tank bottom 11 and prevents sludge from being scraped. Is configured to be driven. Further, the scraper 42 attached to the lower portion of the horizontal beam 41B can be configured to move in contact with the bottom of the tank when moving in either the front or back direction. As a result, a large amount of sludge settles, and further, the sludge attracting device 4 scrapes a large amount of sludge to smoothly reciprocate the lifting beam 41A of the sludge attracting beam 41 of the sludge attracting device 4. Can be carried out to ensure that the sludge that has settled is attracted,
And, it can be performed stably.

The scraper 42 is provided between the two sludge attracting beams 41, 41 arranged in parallel to the left and right, specifically, the lifting beam 41A at the front portion and the horizontal beam 4 at the rear portion.
1B between the sludge attracting beams 41, 41, preferably at a predetermined interval equal to or shorter than the stroke length of the sludge attracting device 4 reciprocally driven by the drive device 5, at substantially equal intervals. Install in parallel. Also, scraper 4
2 moves the scraper 42 to the tank bottom 11 when moving forward.
Can be moved along with, the scraped sludge can be scraped up reliably and stably, and when moving backward, make sure that the scraper 42 sinks into the sludge that settled. Will be possible. In addition, the lifting beam 41A and the horizontal beam 41B provided with the scraper 42 smoothly move back and forth along the bottom 11 of the sewage treatment tank 1, so that the lifting beam 41A and the horizontal beam 41B are supported by the horizontal beam rear part. A shoe or a roller 43 is provided at the end position and serves as a support portion for the sludge attracting device 4.

The drive device 5 is installed in front of the central portion of the sewage treatment tank 1, that is, on the water surface on the sludge pit P side. The driving device 5 is not particularly limited, but a large number of pin racks are provided on the substantially horizontal inner guide rail at equal intervals, and the outer guide rail is arranged so as to surround the outer circumference of the inner guide rail. 1 to form a guide rail, and to drive the pin wheel that meshes with the pin rack and moves around the guide rail (substantially rectangular motion) by a prime mover. 2 or rods 60 and 61 as shown in FIG. 2 are suspended and supported, and the post 7 or rods 60 and 61 are configured to reciprocate. Then, when the pin wheel moves above and below the pin rack for the ascending / descending distance H of the ascending / descending beam 41A, the ascending / descending beam 41A is lifted so that the scraper 42 is separated from the tank bottom 11, and the entire sludge attracting device retreats. Further, when the sludge attracting device 4 in which the pin wheel moves below the pin rack is advanced, the elevating beam 41A descends, the scraper 42 comes into contact with the tank bottom 11, and the sludge advances the sludge attracting direction to remove sedimented sludge. Set it so that it will be drawn to the pit side.
The stroke of the scraper is the reciprocal movement distance of the pin wheel that moves along the pin rack.

In this case, the drive device 5 and the sludge attracting device 4 are connected by the post 7 as shown in FIG. The sewage treatment tank 1 that supports the sludge attracting device 4 is
As shown in FIG. 1, when there are two or more layers,
Sludge attracting beams 41, 41 of the sludge attracting device 4 are arranged in each layer, and the elevating beams 41A of the upper and lower layers are simultaneously hung by the suspension posts 7 so as to be supported. Further, when the sludge attracting device 4 is suspended from the drive device 5, in the case of one layer, it can be performed by a plurality of rods 60 and 61 as shown in FIG.

On the other hand, as shown in FIGS. 1 and 2, the scum scraping device 6 establishes struts 62, 63 on the elevating beam 41A of the sludge scraping beam 41 of the sludge scraping device 4, and the struts 62. , 63, the scum beam 64 is formed so as to be substantially horizontal. This scum beam 64 has two scum beams 64, 64 arranged in parallel at both ends in the width direction of the sewage treatment tank 1 like the sludge scratching beam 41, and the scum beams 64, 64 are disposed between the scum beams 64, 64. A plurality of popular scum blades 65 are provided in FIGS.
As shown in, it is constructed by erection. As a result, the scum scraping device 6 moves the scum floating scraper on the water surface when the scum scraping device 6 moves backward on the return path of the sludge scraping device 4 that moves by lifting the sludge scraping beam. It is installed so that it can be drawn to the anti-sludge pit side. The scum scraping device 6 is configured so that the scum skimmer K arranged in the sewage treatment tank 1 and the scum scraping device 6 moving on the return path side do not come into contact with each other.

The scum beam 64 provided with the scum blade of the scum scraping device 6 divides the scum beam into a front scum beam 64A and a rear scum beam 64B, and a pin joint is provided between the front and rear scum beams 64A and 64B. The rear scum beam 64B is connected so as to be bendable at 64C, and the rear scum beam 64B is configured to be suspended and supported by the scum lifting device 8 via the scum suspension rod 9 at a position rearward of the pin joint 64C.

The scum lifting device 8 is a sludge attracting device 4.
Although it does not have a drive mechanism inside, it moves following the drive device 5 so that the stroke before and after it is equal to the stroke of the drive device 5. Also, the ascending / descending distance (height) by the scum lifting device 8 is such that when the front scum beam 64A rises and retracts, the scum floating on the water surface by the scum blade projecting upward on the front scum beam 64A Rear scum beam 64
B is in a state of being lifted through the scum suspension rod 9 so that the rear end thereof does not hang down under its own weight and sink below the water surface.
Further, the scum blade protruding from the rear scum beam 64B is used to scrape scum floating on the water surface toward the scum skimmer side, as in the front scum beam 64A. The scum scraping device 6 is configured such that the front scum beam 64A and the rear scum beam 64 are arranged when the sludge scraping device 4 moves forward.
B is lowered together with the scum blade, and almost all of the scum blade is submerged below the water surface, so that scum floating on the water surface is prevented from being scratched to the side opposite to the scum skimmer. In the multi-tank type, as shown in FIG. 1, only the scum scraping device 6 installed in the tank on the upper floor supports the rear scum beam 64B by the scum lifting device 8 via the scum suspension rod 9. However, as shown in FIG. 3, the rear scum beams 64B, 64B in the upper and lower layers can be suspended and supported by the same scum suspension rod 9. 4 shows only the scum scraping device 6 installed in the tank on the upper floor, the rear scum beam 64B is suspended and supported by the scum lifting device 8 through the scum suspension rod 9, and the scum scraping device of the lower layer is supported. In the shift device 6, the front and rear scum beams 64A and 64B are flexibly connected by a pin joint 64C, but the scum lifting device 8 does not suspend and support the scum beams.

FIG. 5 shows an embodiment of the scum lifting device 8. This scum raising / lowering device 8 has a roller 91 attached to the upper end of a scum hanging rod 9 which suspends and supports the scum raising / lowering device 8.
The guide rail is movably supported. This guide rail has two upper and lower stages arranged in parallel. The lower rail 81 moves the roller 91 when the scum raising / lowering device 8 descends and moves forward, while the scum raising / lowering device 8 rises and moves backward. It comprises an upper rail 82 which moves at that time, and levers 83, 84 tiltably arranged at both ends of the upper rail 82 so that the roller 91 can smoothly and cyclically move between the lower rail 81 and the upper rail 82. The lever 83 is configured such that its tip always hangs down and comes into contact with the lower rail, and the lever 84 is always lifted up and separated from the lower rail. When the roller 91 moves, the levers 83 and 84 swing with a cola. To allow circulation in one direction. As a result, when the roller 91 moves backward from the illustrated position, that is, when it moves to the right, the lower rail 81
It moves on the lever 83 hanging from above, moves to the upper rail 82, and retreats on this upper rail 82. At this time, the rear scum beam 64B is lifted up, and the scum floating on the water surface is scraped to the scum skimmer side by the scum blade together with the front scum beam 64A. Then, when the roller 91 reaches the end portion of the upper rail 82, the lever 84 that is jumping up is pushed down by the load of the roller, and the lower rail 81 is moved from above the lever 84 and the load of the roller is removed. The lever 84 will automatically return and spring up again. In this state, when the roller 91 moves forward, that is, moves to the left by the scum lifting device 8, the roller 91 moves along the lower rail 81 under the lever 84 that is jumping up. At this time, the rear scum beam 64 is at the lowered position, and the scum is not scraped. And roller 9
When 1 comes below the hanging lever 83, the lever 83 is pushed up by the roller 91 to lower the lower rail 81.
When it moves up and the lever 83 passes under the lever 83,
The lever 83 will automatically hang down again. In this way, the roller 91 circulates once and repeats this operation in sequence, and when moving on the upper rail 82, the rear scum beam 64B moves up by the length A thereof.

FIG. 6 shows a different embodiment of the scum lifting device 8. The scum raising / lowering device 8 is configured to support a roller 91 attached to an upper end of a suspension post for suspending and supporting a rear scum beam so as to be movable along an inclined guide rail 85. This guide rail 85 is designed so that the sludge pit side is low and horizontal,
The end portion 85a on the scum skimmer side is formed so as to be curved so as to be higher, and the height difference is set such that the tip of the scum blade protrudes from the water surface or is below the water surface, and the total length is The stroke of the scum lifting device 8 is set. When the sludge attracting device 4 and the scum attracting device 6 move by moving the roller 91 to the right around the guide rail 85, according to the moving direction, the water surface is the same as in the embodiment shown in FIG. Try to scrape the scum that floats on. Scum scratching device 6
However, when the roller 91 is at the left end and does not move in the rightward retreating direction, the roller 91 is at the balance position X and moves on the guide rail 85 to scrape the scum.
When the scum scraping device 6 retracts and the roller 91 reaches the end position of the guide rail 85, the roller is once lifted along the end shape of the guide rail 85, and then the guide rail 85. Of the guide rail 85, and falls from the guide rail 85 due to its own weight. Next, when the sludge scraping device 4 moves forward to move to the sludge scraping operation,
The roller 91 of the scum scraping device 6 is connected to the guide rail 8
5, the roller 91 moves along the lower surface of the guide rail 8
Since it is pressed down by 5, the scum blade is below the surface of the water, and the scum can be returned so as to prevent the scum from being scraped toward the sludge pit side. Also, the roller 91
When the trailing edge of the swing stroke exceeds the tip of the guide rail 85 at the front end, it floats and returns to the balance position X. By repeating this operation, the scum floating on the water surface is scraped.

FIG. 7 shows another embodiment of the scum scraping device 6. The rope 87 is hung on the wheel 86 of the scum lifting device 8 and both ends of the rope 87 are fastened to the front and rear of the rear scum beam to be stretched, and the rear scum beam is moved up and down through the rope 87 by the movement of the wheel 86. It is configured to be suspended and supported as described above. The operation is the same as in the previous embodiment. FIG. 8 shows a floating and setting blade W at the rear end of the rear scum beam 64B of the embodiment shown in FIG.
As a result, when the rear scum beam 64B moves back and forth, particularly when moving in the scum scraping direction, buoyancy is generated by the floating and sinking blade W so that the scum blade of the rear scum beam 64B floats above the water surface. West,
Also, when moving in the opposite sludge scraping direction, sewage is agitated.

The scum scraping device in the sludge scraping machine of the present invention has been described above based on a plurality of embodiments, but the present invention is not limited to the configurations described in the above embodiments, and each embodiment is not limited thereto. The configurations described in the examples can be combined as appropriate, and the configurations can be appropriately changed without departing from the spirit thereof.

[0036]

According to the scum raking device in the sludge raking machine of the present invention, the scum beam having the scum blade of the scum raking device is divided into front and rear parts, and the middle part is connected so as to be bendable, and Since the partial scum beam is supported by the sludge attracting device via the strut, the rear scum beam is raised by the scum lifting device when the sludge attracting device moves backward, and when it moves forward, it descends.
Even if the sewage treatment tank becomes longer and the scum scraping device becomes longer following it, the rear scum beam is forcibly lifted and lowered by the scum lifting device, so even the long scum scraping device can be lifted and lowered uniformly over its entire length. You can secure a stroke,
Scum floating on the water surface of a long sewage treatment tank can be reliably scraped and discharged, and scum can be efficiently treated.

Further, since the scum skimmer is arranged at a position rearward of the support portion of the sludge scraping device, the scum scraped by the scum scraping device can be reliably discharged from the scum skimmer.

Further, by providing the sewage treatment tanks in a plurality of layers, the installation area of the sewage treatment tanks can be made small, and the sludge and the sludge settling on the bottoms of the respective stages can be reduced by one drive installed on the water surface. Scum floating on the water surface can be scraped off and discharged at the same time.

Further, since the scum raising / lowering device is constituted so that the roller attached to the upper end of the suspension post for suspending and supporting the rear scum beam is movably supported along the inclined guide rail, a simple scum is provided. The elevating device allows the rear scum beam to move smoothly along the guide rails following the drive of the drive device, whereby the elevating operation can be performed reliably and automatically.

A roller having a scum lifting device mounted on the upper end of a suspension post for suspending and supporting the rear scum beam is mounted on the rear scum beam by means of a guide rail that is turned up and down when reciprocating. Since the roller is guided, the roller can be reliably circulated in one direction, and the rear scum beam suspended and supported thereon can be reliably moved up and down.

Further, since the scum scraping device is constructed so that the ropes fastened to the front and rear of the rear scum beam are hung on the moving wheel of the scum lifting device so as to be suspended and supported, the structure of the scum scraping device is simple. And the operation can be performed more reliably.

[Brief description of drawings]

FIG. 1 shows an embodiment in which a scum scraping device in a sludge scraping machine of the present invention is applied to a two-tiered wastewater treatment tank,
(A) is a plan view and (B) is a vertical sectional front view.

FIG. 2 shows an embodiment in which the scum scraping device in the sludge scraping machine of the present invention is applied to a one-layer type wastewater treatment tank (however, the scum lifting device is not shown), (A) is a plan view,
(B) is a vertical sectional front view.

FIG. 3 is a vertical cross-sectional front view showing a different embodiment of a scum scraping device in a sludge scraping machine implemented in a two-tiered wastewater treatment tank.

FIG. 4 is a vertical cross-sectional front view showing a different embodiment of a scum scraping device in a sludge scraping machine implemented in a two-tiered wastewater treatment tank.

FIG. 5 is a front view for explaining the operation of the scum scraping device in the sludge scraping machine of the present invention.

[Fig. 6] Fig. 6 is an operation explanatory view of a different embodiment of the scum scraping device in the sludge scraping machine of the present invention.

FIG. 7 is an operation explanatory view of another embodiment of the scum scraping device in the sludge scraping machine of the present invention.

[Fig. 8] Fig. 8 is an operation explanatory view of another embodiment of the scum scraping device in the sludge scraping machine of the present invention.

[Explanation of symbols]

1 Sewage treatment tank 11 tank bottom 4 Sludge attracting device 41 Sludge drawing beam 42 scraper 5 drive 6 Scum device 60, 61 rod 64 scum beam 64A front scum beam 64B rear scum beam 64C pin joint 65 scum blade 7 hanging post 8 scum lifting device 9 Scum hanging rod

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Eiichi Muto             Hitachi, 3-4-1, Shimosaka, Amagasaki-shi, Hyogo             Kiden Kogyo Co., Ltd. (72) Inventor Atsuo Hirai             Hitachi, 3-4-1, Shimosaka, Amagasaki-shi, Hyogo             Kiden Kogyo Co., Ltd. F-term (reference) 4D051 AA04 AB03 CA02 DB02 DD01                       DD23

Claims (6)

[Claims] 1. A sludge scraping device, which is disposed along the bottom of a wastewater treatment tank and moves up and down and reciprocates to scrape sludge toward the sludge pit side, and the sludge scraping device. A scum scraping device in a sludge scraper comprising a driving device installed on the water surface for suspending and supporting and vertically moving and reciprocating, and a scum scraping device driven in conjunction with the sludge scraping device. The scum beam provided with the scum blade of the scum scraping device is divided into front and rear parts, and the middle part is connected so as to be bendable, and the front scum beam is supported by the sludge scraping device via a strut, and the rear part. A scum attracting device in a sludge attracting device, wherein a scum beam is raised by a scum lifting device when the sludge attracting device moves backward and descends when the sludge attracting device moves forward. 2. The scum attracting device in a sludge attracting device according to claim 1, wherein the scum skimmer is arranged at a position rearward of a support portion of the sludge attracting device. 3. The scum scraping device for a sludge scraping machine according to claim 1, wherein the wastewater treatment tank has a plurality of layers. 4. The scum raising / lowering device is configured to support a roller attached to an upper end of a suspension post for suspending and supporting a rear scum beam so as to be movable along an inclined guide rail. The scum scraping device in the sludge scraping machine according to 1, 2, or 3. 5. A scum lifting device, wherein a roller attached to an upper end of a suspension post for suspending and supporting a rear scum beam is supported by a guide rail which is vertically switched when reciprocating and is vertically moved. The scum raking device in the sludge raking machine according to claim 1, 2 or 3, which is configured. 6. The scum scraping device is configured to be connected by a cord fastened to the front and rear of a rear scum beam, and a part of the cord is hung on a moving wheel of a scum lifting device to be suspended and supported. The scum scraping device in the sludge scraping machine according to claim 1, 2, or 3.