JP7371908B2 - Contaminant removal screen device - Google Patents

Description

The present invention relates to a contaminant removal screen device that has an interval that connects the upstream and downstream sides of received wastewater and transports contaminants that are trapped and cannot pass through the interval upward.

In a sewage treatment system, generally, wastewater consisting of sewage flows and is purified through a settling tank, a first settling tank, a reaction tank, and a final settling tank in the listed order. Among these, for example, in the first settling tank, sewage (raw sludge) containing sludge that has settled at the bottom of the tank is transferred to the outside of the first settling tank by a sludge pump or the like, where it is concentrated, dehydrated, and then incinerated. Since raw sludge contains impurities such as sludge, impurities are generally removed from raw sludge using a contaminant removal screen device for raw sludge before it is concentrated and dehydrated. Ru. Furthermore, sewage containing scum (scum water), which is a contaminant floating near the water surface of the primary sedimentation tank, is collected in a scum pit, and then transferred from the scum pit to the outside of the primary sedimentation tank by a scum pump. The scum water that is first transferred to the outside of the settling area is returned to the sewage treatment plant after the scum is removed by a scum contaminant removal screen device. These impurity removal screen devices are arranged in a water tank that receives raw sludge and scum water from the initial settling tank (see, for example, Patent Document 1 and Patent Document 2).

The contaminant removal screen device described in Patent Document 1 and Patent Document 2 includes a plurality of fixed screen members and a movable screen member disposed between the plurality of fixed screen members. The fixed screen members each extend obliquely upward, and the uppermost portions protrude from the water surface of the aquarium or the like. Further, the fixed screen member has a step-like shape in which a plurality of fixed step portions are arranged side by side in the extending direction. The operating screen member also extends obliquely upward and has a step-like shape in which a plurality of operating steps are arranged in the extending direction. The active screen member moves contaminants toward the top of the stationary screen member by repeatedly moving upward and downward relative to the stationary screen member. The contaminants transferred to the top of the fixed screen member fall toward a chute provided on the downstream side of the fixed screen member, and are discharged to the outside of the contaminant removal screen device. In the contaminant removal screen device described in Patent Document 1 and Patent Document 2, even if the gap between the stationary screen member and the movable screen member is filled and clogged by the captured contaminants that cannot pass through the gap, As soon as the active screen member is moved, all captured foreign matter begins to be transferred, so that clogging can be cleared quickly. Therefore, even if a large amount of sewage or a large amount of foreign matter flows into the aquarium, by moving the operating screen member, the rise in the water level of the aquarium can be immediately suppressed, and the sewage will not overflow outside the aquarium. You can prevent it from getting stuck.

Japanese Patent Application Publication No. 2014-114574 Japanese Patent Application Publication No. 2015-017462

However, the contaminant removal screen devices described in Patent Document 1 and Patent Document 2 have a problem in that a large amount of power is consumed because the heavy operating screen member is repeatedly moved upward and downward.

In view of the above circumstances, an object of the present invention is to provide a contaminant removal screen device that suppresses power consumption.

A contaminant removal screen device of the present invention that solves the above object includes a plurality of fixed screen members provided at intervals,
A first operating screen member and a second operating screen member that transport contaminants upward by repeatedly moving upward and downward between the plurality of fixed screen members;
a drive device that moves the first operating screen member and the second operating screen member upward;
The driving device includes a first frame that holds the plurality of first operating screen members, a second frame that holds the plurality of second operating screen members, and a driving force for each of the first frame and the second frame. and an actuator that drives the drive shaft, and by driving the first frame and the second frame, the plurality of first operating screen members and the plurality of second operating screen members It is characterized in that it moves upward at a different timing.
In this foreign matter removal screen device, the first frame has a pair of left and right first frame portions arranged at intervals in the width direction, and a first horizontal member connecting the first frame portions. can be,
The plurality of first operating screen members are fixed to the first cross member,
The second frame has a pair of left and right second frame parts arranged at intervals in the width direction, and a second cross member connecting the second frame parts,
The plurality of second operating screen members may be fixed to the second cross member.
Further, a plurality of fixed screen members provided at intervals,
A first operating screen member and a second operating screen member that transport contaminants upward by repeatedly moving upward and downward between the plurality of fixed screen members;
a drive device that moves the first operating screen member and the second operating screen member upward;
The driving device may be characterized in that the first operating screen member and the second operating screen member are moved upward at different timings.

According to the contaminant removal screen device of the present invention, the load on driving the drive device is reduced, and the contaminant removal screen device can be driven with less electric power.

Here, the drive device moves the second operating screen member downward while moving the first operating screen member upward, and when moving the first operating screen member downward. The second movable screen member may be moved upward. Further, the drive device may move the first operating screen member and the second screen member in a circular orbit.

Further, in the contaminant removal screen device of the present invention, the drive device includes a first frame holding the first operating screen member, a second frame holding the second operating screen member, the first frame and The second frame may include a drive shaft that transmits a driving force to each of the second frames, and an actuator that drives the drive shaft.

According to this aspect, the driving force of the actuator can be transmitted to the first frame and the second frame with a simple configuration, and the first screen member and the second movable screen member can be moved, respectively.

Furthermore, in the contaminant removal screen device of the present invention, a plurality of the fixed screen members are arranged side by side in the width direction,
The first frame and the second frame may be arranged with a gap in the width direction.

By doing so, the configuration of the drive device can be simplified.

In addition, in the contaminant removal screen device of the present invention, among the received wastewater, the wastewater flowing toward the gap is separated from the side where the first operating screen member is arranged and the side where the second operating screen member is arranged. It may be provided with a flow dividing member that diverts the flow to the side.

The flow dividing member can prevent contaminants from entering the gap and passing through the contaminant removal screen device.

According to the present invention, it is possible to provide a contaminant removal screen device that suppresses power consumption.

It is a diagram schematically showing some facilities in a sewage treatment plant. It is a front view of a screen unit for raw sludge provided with a contaminant removal screen device for raw sludge of the present embodiment. 3 is a sectional view taken along line AA of the raw sludge screen unit shown in FIG. 2. FIG. It is a front view of a contaminant removal screen device for raw sludge. It is a figure which shows operation|movement of a 1st operating screen member and a 2nd operating screen member step by step.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram schematically showing some facilities in a sewage treatment plant.

This FIG. 1 shows a settling tank 1, a raw sludge screen unit 2, a scum pit 3, and a scum screen unit 4.

The settling tank 1 shown in Fig. 1 receives wastewater (sewage) from one longitudinal end (left side in Fig. 1), settles sludge contained in the received wastewater to the bottom of the pond, and then settles the sludge contained in the received sewage to the bottom of the pond. Drain from the right side). Hereinafter, the left direction in FIG. 1 will be referred to as upstream, and the right direction in FIG. 1 will be referred to as downstream. A sludge pit 11 is provided at the bottom of the sedimentation tank 1 on the upstream side, and a drainage gutter 12 is provided near the water surface on the downstream side. In the settling tank 1, sludge that has settled at the bottom of the tank is collected into a sludge pit 11 by a sludge scraper (not shown). The sludge collected in the sludge pit 11 is sent by a sludge pump 13 to a raw sludge screen unit 2 installed outside the settling tank 1. The sludge collected in the sludge pit 11 contains impurities such as scum. Hereinafter, the sewage containing sludge sent from the sludge pit 11 to the raw sludge screen unit 2 will be referred to as raw sludge. The raw sludge screen unit 2 is provided with a raw sludge contaminant removal screen device 6. As will be described in detail later, the raw sludge contaminant removal screen device 6 removes contaminants contained in the raw sludge. The raw sludge from which contaminants have been removed by the raw sludge contaminant removal screen device 6 is then sent to a sludge concentration treatment facility or a sludge dewatering treatment facility. Further, in the settling tank 1, scum floating near the water surface is scraped up to the drainage gutter 12 by a scum scraper (not shown). The drainage gutter 12 is connected to the scum pit 3, and the scum-containing wastewater (scum water) is collected in the scum pit 3, and then sent from the scum pit 3 to a scum screen installed outside the settling tank 1 by a scum pump 31. Sent to Unit 4. The scum water collected in the scum pit 3 also contains impurities such as scum. The scum screen unit 4 is provided with a scum contaminant removal screen device 7. This scum contaminant removal screen device 7 removes scum, which is a contaminant contained in the scum water. The wastewater from which scum has been removed by the scum contaminant removal screen device 7 is returned to the sewage treatment plant.

Next, the raw sludge screen unit 2 equipped with the raw sludge contaminant removal screen device 6 will be described as an example, but the scum screen unit 4 equipped with the scum contaminant removal screen device 7 will also be described. The same is true. The raw sludge contaminant removal screen device 6 and the scum contaminant removal screen device 7 are both examples of contaminant removal screen devices.

FIG. 2 is a front view of a raw sludge screen unit provided with the raw sludge contaminant removal screen device of this embodiment.

As shown in FIG. 2, the raw sludge screen unit 2 includes a water tank 5 and a raw sludge contaminant removal screen device 6. The screen unit 2 for raw sludge shown in FIG. 2 receives raw sludge from the left side of the figure (see thick arrow in the figure). Hereinafter, the left side in FIG. 2 will be referred to as the upstream side, and the right side will be referred to as the downstream side. Further, in FIG. 2, the direction perpendicular to the paper surface is referred to as the width direction. The raw sludge contaminant removal screen device 6 includes a screen body 60, which will be described in detail later. In FIG. 2, only the upstream side surface of the screen body 60 is shown by a thick broken line.

In the lower half of the upstream side wall of the aquarium 5 shown in FIG. An inclined portion 52 is provided which is inclined toward the upstream side as it approaches. Therefore, the water tank 5 has a shape that is narrower on the bottom 5a side. This water tank 5 receives the sludge collected in the sludge pit 11 shown in FIG. 1 as raw sludge. An inflow pipe 53 is provided on the upstream side of the water tank 5. Raw sludge is supplied to the inflow pipe 53 by driving the sludge pump 13, flows into the water tank 5 from the tip 531 of this inflow pipe 53, and flows toward the downstream side (many thin lines in the figure). (see arrow). Note that the distal end portion 531 of the inflow pipe 53 is formed in a fan shape that widens toward the downstream side when viewed from above. In addition, impurities X such as sludge contained in the raw sludge are blocked by the screen body 60 provided in the raw sludge contaminant removal screen device 6, and accumulate near the water surface on the upstream side of the screen body 60. It is in a state of

The raw sludge screen unit 2 is provided with an emergency overflow unit 54 upstream of the screen body 60 in the raw sludge contaminant removal screen device 6 . Further, a drainage overflow unit 55 is provided downstream of the screen body 60. Both the emergency overflow unit 54 and the drainage overflow unit 55 have drainage basins 541, 551 and weir plates 542, 552. These drainage basins 541 and 551 are both provided so as to protrude outward in the width direction of the water tank 5. The dam plate 552 of the drainage overflow unit 55 is provided at the boundary between the inside of the water tank 5 and the inside of the drainage basin 551, and the inside of the water tank 5 and the inside of the drainage basin 551 are connected at a portion above the dam plate 552, The parts below the weir plate 552 are not connected. When the water level in the water tank 5 exceeds the height of the upper end of the weir plate 552, the wastewater in the water tank 5 flows over the weir plate 552 into the drainage basin 551. The sewage in the water tank 5 referred to here is sewage containing raw sludge that has passed through the screen body 60, that is, sludge from which impurities have been removed by the impurity removal screen device 6 for raw sludge, and this sewage is It is sent to sludge thickening treatment equipment and sludge dewatering treatment equipment, which are treatment process equipment. In this way, the raw sludge that has passed through the screen body 60 provided in the raw sludge contaminant removal screen device 6 is drained out of the raw sludge screen unit 2 by the drainage overflow unit 55.

The structure of the emergency overflow unit 54 is also the same as that of the drainage overflow unit 55, but the emergency overflow unit 54 is provided at a higher position than the drainage overflow unit 55. If the water level of the water tank 5 rises from the normal water level and exceeds the weir plate 542 of the emergency overflow unit 54, such as when the raw sludge contaminant removal screen device 6 malfunctions, the water level in the drainage basin 541 of the emergency overflow unit 54 will rise. flows into. The raw sludge in the water tank 5 referred to here is raw sludge before passing through the screen body 60, that is, sewage containing sludge before foreign substances are removed by the raw sludge contaminant removal screen device 6, This wastewater is returned to the upstream end of the raw sludge contaminant removal screen device 6.

Next, the raw sludge contaminant removal screen device 6 will be explained. The raw sludge contaminant removal screen device 6 includes a screen body 60, a base frame 64, and a drive device 65. The base frame 64 is attached to a pair of support legs 69 fixed to the edge of the water tank 5. Although one of the pair of support legs 69 is shown in FIG. 2, the other support leg 69 is located on the opposite edge of the water tank 5 across the raw sludge contaminant removal screen device 6 in the width direction. is fixed. The base frame 64 and the support leg 69 are rotatably connected by a rotating shaft 69a, and are fixed at an angle shown in FIG. 2 by bolts (not shown).

The screen body 60 is arranged in the aquarium 5 in an inclined position so that the lower part is located on the upstream side of the aquarium 5 and the upper part is located on the downstream side. The top of this screen body 60 is located above the weir plate 542 of the emergency overflow unit 54.

FIG. 3 is a sectional view taken along line AA of the raw sludge screen unit shown in FIG. Moreover, FIG. 4 is a front view of the contaminant removal screen device for raw sludge. In FIG. 4, a cover 648 attached to the widthwise end of the raw sludge contaminant removal screen device 6 is not shown.

As shown in FIG. 3, the screen body 60 includes a plurality of fixed screen members 61, a plurality of first movable screen members 62, and a plurality of second movable screen members 63. In addition, in FIG. 3, in order to simplify the drawing, some of the fixed screen member 61, the first movable screen member 62, and the plurality of second movable screen members 63 are omitted. In this embodiment, the number of first operating screen members 62 and the number of second operating screen members 63 are the same. Each of the fixed screen member 61, the first movable screen member 62, and the plurality of second movable screen members 63 is a long stainless steel member arranged at an angle so as to be located on the downstream side as it goes upward. be. However, the fixed screen member 61, the first operating screen member 62, and the plurality of second operating screen members 63 may be made of other metals or resins as long as they have excellent corrosion resistance and durability against raw sludge. Alternatively, they may be made of different materials. The plurality of fixed screen members 61 are arranged at intervals from each other and lined up in the entire width direction except for the center portion in the width direction. The first operating screen members 62 are arranged in a row in the width direction on the right half of the aquarium 5 when viewed from the upstream side, and the second operating screen members 63 are arranged in a line in the width direction on the left half of the aquarium 5 when viewed from the upstream side. It is located in Hereinafter, the right side of the aquarium 5 when viewed from the upstream side will be referred to as the right side of the tank, and the left side of the aquarium 5 when viewed from the upstream side of the aquarium 5 will be referred to as the left side of the tank. Each of the plurality of first operating screen members 62 is arranged between two fixed screen members 61. That is, the fixed screen members 61 and the first movable screen members 62 are alternately arranged at predetermined intervals W (for example, 2 mm or more and 6 mm or less) in the width direction over almost the entire right half of the tank. Similarly, each of the plurality of second movable screen members 63 is arranged between two fixed screen members 61. That is, the fixed screen members 61 and the second movable screen members 63 are alternately arranged at a predetermined interval W in the width direction over almost the entire left half of the tank. The predetermined interval W is an interval connecting the upstream side and the downstream side, which is set based on the balance between the flow rate of raw sludge passing through the raw sludge contaminant removal screen device 6 and the size of the device. Among the contaminants contained in the raw sludge, the contaminants that cannot pass through the predetermined interval W are captured by the screen body 60 so as to close the predetermined interval W on the upstream side of the screen body 60. In addition, in FIG. 3, the thickness of the fixed screen member 61, the first movable screen member 62, and the second movable screen member 63 in the width direction, the distance between the fixed screen member 61 and the first movable screen member 62, and the fixed screen member 61 and the second movable screen member 63 are shown. The spacing of the second working screen member 63 is shown exaggerated.

On the upstream side of the fixed screen member 61, a plurality of fixed step portions 611 are provided along the longitudinal direction. Moreover, a plurality of first operating step portions 621 are provided along the longitudinal direction on the upstream side of the first operating screen member 62, and a plurality of first operating step portions 621 are provided on the upstream side of the second operating screen member 63 along the longitudinal direction. A plurality of step portions 631 are provided. Here, the longitudinal direction of the fixed screen member 61, the longitudinal direction of the first movable screen member 62, and the longitudinal direction of the second movable screen member 63 are directions in which contaminants are transferred, as will be described later. That is, the fixed screen member 61, the first movable screen member 62, and the second movable screen member 63 are all provided with stair-like steps lined up in the foreign matter transfer direction. Furthermore, a fixed uppermost step portion 612 is provided at the top of each of the plurality of fixed screen members 61. The fixed uppermost step part 612 is made of a separate member that is wider than the fixed step part 611. The fixed uppermost section 612 maintains the interval between the fixed screen member 61 and the first operating screen member 62 or the interval between the fixed screen member 61 and the second operating screen member 63 at a predetermined interval W. Moreover, the fixed uppermost stage part 612 is located above the water surface of raw sludge (sewage).

The base frame 64 includes a pair of end base plates 641, a pair of center base plates 642, two fixed screen horizontal members 643, a drive bearing 644, a driven bearing 645, a flow divider plate 646, and a cross plate 647 ( (see FIG. 4) and a pair of covers 648. The pair of end base plates 641 extend from the bottom 5 a of the aquarium 5 to above the upper end of the aquarium 5 along the side wall surface of the aquarium 5 at both ends of the aquarium 5 in the width direction. Further, the pair of central base plates 642 are arranged at the center portion of the water tank 5 in the width direction, and extend from the bottom 5a of the water tank 5 to above the upper end of the water tank 5. A drive bearing 644 and a driven bearing 645 are arranged between a pair of central base plates 642. The pair of end base plates 641 and the pair of center base plates 642 have substantially the same shape when viewed from the width direction. Although the cross plate 647 is omitted in FIG. 3 to show the internal structure, the cross plate 647 extends in the width direction on the right side of the tank and the left side of the tank, and has an end base plate 641 and a center base plate 642. It is a plate-shaped member that connects the The drive bearing 644 and the driven bearing 645 are arranged at the center of the water tank 5 in the pond width direction and are fixed to a cross plate 647.

Two fixed screen horizontal members 643 are stretched between the pair of end base plates 641. Each of the two fixed screen horizontal members 643 has both ends in the width direction fixed to the end base plate 641. Therefore, the two fixed screen cross members 643 connect the pair of end base plates 641. Note that the fixed screen horizontal member 643 may have a configuration in which it is divided at the center portion in the width direction. In the case of a split configuration, both ends of one of the split fixed screen horizontal members 643 are fixed to the end base plate 641 on the right side of the tank and the center base plate 642 on the right side of the tank, and Both ends of the material 643 may be fixed to the end base plate 641 on the left side of the tank and the center base plate 642 on the left side of the tank. The fixed screen member 61 is fixed to the upstream side surface of this fixed screen cross member 643. Therefore, the fixed screen member 61 is fixed at a predetermined position in the aquarium 5.

The flow dividing plate 646 is fixed to the central base plate 642 near the center of the water tank 5 in the width direction. This flow dividing plate 646 corresponds to an example of a flow dividing member. The flow divider plate 646 is made of a stainless steel plate, and the downstream portion thereof is fixed to each of the pair of central base plates 642. The upstream end surface of the flow dividing plate 646 is bent into a U-shape projecting toward the upstream side so as to cover between the pair of central base plates 642 on the upstream side of the screen body 60, and the downstream end of the flow dividing plate 646 , has reached the screen body 60. This flow dividing plate 646 diverts the raw sludge flowing from the upstream side toward the flow dividing plate 646 to the right side of the tank where the first working screen member 62 is arranged and the left side of the layer where the second working screen member 63 is arranged. It is something that makes you This flow dividing plate 646 prevents raw sludge from directly flowing into the space between the pair of central base plates 642 from the upstream side of the screen body 60 together with foreign matter such as residue. The flow dividing plate 646 prevents foreign objects from getting entangled with the first driven eccentric cam 6541, the second driven eccentric cam 6542, the driven bearing 645, and the first frame 651 and second frame 652, which will be described later, located near the center in the width direction. This also prevents foreign matter from passing between the center base plate 642 and the central base plate 642.

The pair of covers 648 are arranged outside the pair of end base plates 641 and cover both end surfaces in the width direction of the raw sludge contaminant removal screen device 6, respectively. A rubber seal 6481 that protrudes toward the side wall of the water tank 5 and extends from the bottom 5a to the upper end of the water tank 5 is attached to the upstream end surface of the cover 648. This rubber seal 6481 is used to prevent foreign matter from slipping downstream of the raw sludge contaminant removal screen device 6 from the gap between the widthwise end face of the raw sludge contaminant removal screen device 6 and the side wall of the water tank 5. belongs to.

The drive device 65 includes a first frame 651, a second frame 652, a drive shaft 653, a driven shaft 654, and an actuator 655. The first frame 651 is arranged on the right side of the tank. The first frame 651 includes a first right frame 651R, a first left frame 651L, and two first operating screen cross members 6511. The first right frame 651R is disposed between the right side wall of the aquarium 5 and the end base plate 641 on the right side of the tank. Further, the first left frame 651L is arranged between the pair of central base plates 642. FIG. 4 shows the first right frame 651R. The first left frame 651L is configured to be plane symmetrical to the first right frame 651R with respect to a plane perpendicular to the width direction. As shown in FIG. 4, the first right frame 651R includes a triangular portion that is hollowed out and has a substantially triangular shape when viewed from the width direction, and an arm portion that extends from the triangular portion toward the drive shaft 653. It is composed of plate-like members that are joined together. Further, as shown in FIG. 3, the two first operating screen horizontal members 6511 are spanned between the first right frame 651R and the first left frame 651L. Both end portions in the width direction of each of the two first operating screen horizontal members 6511 are fixed to the first right frame 651R and the first left frame 651L. Therefore, the two first operating screen horizontal members 6511 connect the first right frame 651R and the first left frame 651L. The first operating screen member 62 is fixed to the upstream side surface of the two first operating screen cross members 6511.

The second frame 652 is arranged on the left side of the tank. The second frame 652 includes a second right frame 652R, a second left frame 652L, and two second operating screen cross members 6521. The second left frame 652L is disposed between the left side wall of the aquarium 5 and the end base plate 641 on the left side of the tank. Further, the second right frame 652R is arranged between the pair of central base plates 642. Therefore, the first frame 651 and the second frame 652 are arranged with a gap in the width direction. This second frame 652 has the same shape as the first frame 651 except for portions related to a second drive position 652a and a second driven position 652b, which will be described later. Further, as shown in FIG. 3, the two second operating screen horizontal members 6521 are spanned between the second right frame 652R and the second left frame 652L. Both ends in the width direction of each of the two second operating screen horizontal members 6521 are fixed to the second right frame 652R and the second left frame 652L. Therefore, the two second operating screen horizontal members 6521 connect the second right frame 652R and the second left frame 652L. The second operating screen member 63 is fixed to the upstream side surface of the two second operating screen cross members 6521.

The drive shaft 653 and the driven shaft 654 are shafts extending in the width direction on the upstream side of the screen body 60. Both ends of the drive shaft 653 and the driven shaft 654 pass through each of the pair of end base plates 641. The drive shaft 653 is rotatably supported by the base frame 64 by a bearing (not shown) fixed to the end base plate 641 and a drive bearing 644 . Drive shaft hanging tools 6533 are attached to inner portions of the pair of end base plates 641 near both ends of the drive shaft 653 in the width direction. Further, the driven shaft 654 is rotatably supported by the base frame 64 by a bearing (not shown) fixed to the end base plate 641 and a driven bearing 645. A driven shaft hanging tool 6543 is attached to the inner side of the pair of end base plates 641 near both ends of the driven shaft 654 in the width direction. The drive shaft hanging tool 6533 and the driven shaft hanging tool 6543 are parts to which hooks are attached when lifting the raw sludge contaminant removal screen device 6 from the water tank 5 for maintenance or the like. Note that of the drive shaft 653 and the driven shaft 654, a portion between the first right frame 651R and the first left frame 651L and a portion between the second right frame 652R and the second left frame 652L are not shown. covered with a protective pipe. The drive shaft suspension tool 6533 and the driven shaft suspension tool 6543 are integrally connected to the protection pipe.

The first frame 651 and the second frame 652 are driven by a common actuator 655. This actuator 655 includes a motor 6551 and a gear box 6552. The gear box 6552 converts the driving force (rotational force) generated by the motor 6551 and the driving direction (rotational direction). A drive shaft 653 is connected to the gear box 6552. The driving force generated by the motor 6551 is transmitted to the drive shaft 653 via the gear box 6552, and acts as a force for rotating the drive shaft 653. However, the motor 6551 may be fixed to the end base plate 641 so that the axial direction of the output shaft coincides with the width direction, and the gear box 6552 may be omitted and the output shaft and the drive shaft 653 may be directly connected. In this case, only the motor 6551 corresponds to an example of an actuator. Similarly, the motor 6551 is fixed to the end base plate 641 so that the axial direction of the output shaft matches the width direction, and the output shaft and the drive shaft 653 are connected by a transmission mechanical element such as a chain that does not change the drive direction. It's okay. In this case, the motor 6551 and its transmission mechanical element correspond to an example of an actuator.

The first frame 651 is supported by two first drive eccentric cams 6531 fixed to a drive shaft 653 and two first driven eccentric cams 6541 fixed to a driven shaft 654. Each of the first right frame 651R and the first left frame 651L has a first drive eccentric cam rotatably located at a first drive position 651a (see FIG. 4) that is eccentric with respect to a drive shaft center 653a that is the axial center of the drive shaft 653. 6531. Specifically, a shaft (not shown) protruding in the width direction from the first drive eccentric cam 6531 is inserted into a hole (not shown) formed in the first right frame 651R, thereby connecting the first right frame 651R and the first right frame 651R. 1 drive eccentric cam 6531 is connected. The first left frame 651L also has a similar configuration and is connected to the first drive eccentric cam 6531. Further, each of the first right frame 651R and the first left frame 651L is rotatably located at a first driven position 651b (see FIG. 4) eccentric to the driven shaft center 654a, which is the shaft center of the driven shaft 654. It is connected to a driven eccentric cam 6541. Specifically, a shaft (not shown) protruding in the width direction from the first driven eccentric cam 6541 is inserted into a hole (not shown) formed in the first right frame 651R, thereby connecting the first right frame 651R and the first right frame 651R. 1 driven eccentric cam 6541 is connected. The first left frame 651L also has a similar configuration and is connected to the first driven eccentric cam 6541. Here, the relative position between the drive shaft center 653a and the first drive position 651a and the relative position between the driven shaft center 654a and the first driven position 651b are in the same positional relationship.

When the actuator 655 is driven, driving force is transmitted from the drive shaft 653 to the first frame 651 via the first drive eccentric cam 6531. As a result, the first frame 651 maintains its posture in a circular orbit whose radius is the distance between the drive axis 653a and the first drive position 651a and the distance between the driven axis 654a and the first driven position 651b when viewed from the width direction. Rotate while holding. At this time, the first operating screen member 62 also rotates together with the first frame 651.

The second frame 652 is supported by two second drive eccentric cams 6532 fixed to a drive shaft 653 and two second driven eccentric cams 6542 fixed to a driven shaft 654. The second right frame 652R and the second left frame 652L are each rotatably connected to the second drive eccentric cam 6532 at a second drive position 652a (see FIG. 4) eccentric to the drive shaft center 653a. Specifically, a shaft (not shown) protruding in the width direction from the second drive eccentric cam 6532 is inserted into a hole (not shown) formed in the second right frame 652R, thereby connecting the second right frame 652R and the second right frame 652R. A two-drive eccentric cam 6532 is connected thereto. The second left frame 652L also has a similar configuration and is connected to the second drive eccentric cam 6532. This second drive position 652a is a position rotated by 180 degrees about the drive shaft center 653a with respect to the first drive position 651a described above. Further, each of the second right frame 652R and the second left frame 652L is rotatably connected to the second driven eccentric cam 6542 at a second driven position 652b (see FIG. 4) eccentric to the driven axis 654a. There is. Specifically, a shaft (not shown) protruding in the width direction from the second driven eccentric cam 6542 is inserted into a hole (not shown) formed in the second right frame 652R, thereby connecting the second right frame 652R and the second right frame 652R. 2 driven eccentric cams 6542 are connected. The second left frame 652L also has a similar configuration and is connected to the second driven eccentric cam 6542. Here, the relative position between the drive shaft center 653a and the second drive position 652a and the relative position between the driven shaft center 654a and the second driven position 652b are in the same positional relationship.

When the actuator 655 is driven, driving force is transmitted from the drive shaft 653 to the second frame 652 via the second drive eccentric cam 6532. As a result, the second frame 652 is
When viewed from the width direction, it rotates while maintaining its posture in a circular orbit whose radius is the distance between the drive axis 653a and the second drive position 652a and the distance between the driven axis 654a and the second driven position 652b. At this time, the second operating screen member 63 also rotates together with the second frame 652.

Next, the operations of the first operating screen member 62 and the second operating screen member 63 in the raw sludge contaminant removal screen device 6 will be explained.

FIG. 5 is a diagram showing the operation of the first operating screen member and the second operating screen member step by step. In FIG. 5, the shapes of the fixed screen member 61, the first movable screen member 62, and the second movable screen member 63 are simplified, and the shapes of the fixed step portion 611, the first movable step portion 621, and the second movable step portion 631 are simplified. Shown in reduced numbers. Furthermore, in order to make it easier to understand the operations of the first operating screen member 62 and the second operating screen member 63, they are shown divided into upper and lower stages. In FIG. 5, the coincidence of the numbers (a1) to (a5) in the upper row and (b1) to (b5) in the lower row indicates that they are at the same timing. In the upper part of FIG. 5, the fixed screen member 61, the first movable screen member 62, the drive axis 653a, and the first drive position 651a are shown. In the lower part of FIG. 5, the fixed screen member 61, the second movable screen member 63, the drive shaft center 653a, and the second drive position 652a are shown. In addition, in FIG. 5, the left side of the figure is the upstream side, and the right side of the figure is the downstream side.

(a1) and (b1) show that the first operating screen member 62 is in the first initial position and the second operating screen member 63 is in the second transport position. Note that FIG. 3 is a sectional view of the states in (a1) and (b1) viewed from the upstream side. As shown in (a1), the lower part of the fixed screen member 61 is located very close to the bottom 5a, and the lower part of the first movable screen member 62 in the initial position is also located very close to the bottom 5a. When viewed from the width direction, the fixed screen member 61 and the first movable screen member 62 overlap, except for the fixed uppermost portion 612 of the fixed screen member 61. In addition, foreign matter is stuck. The height position of the first operating step section 621 which is the ninth step from the bottom of the first operating screen member 62 shown in (a1) and the height of the fixed step section 611 which is also the ninth step from the bottom of the fixed screen member 61. The positions match.

At this time, as shown in (b1), the second movable screen member 63 is moved upward by exactly one step relative to the fixed screen member 61, and when viewed from the width direction, except for the upper end portion and the lower end portion, It overlaps the fixed screen member 61. In addition, the foreign matter X2 is spread from the second operating step section 631, which is the eighth step from the bottom, of the second operating screen member 63 shown in (b1) to the fixed step section 611, which is the ninth step from the bottom of the adjacent fixed screen member 61. It's stuck. The height position of the second operating step section 631 which is the eighth step from the bottom of the second operating screen member 63 shown in (b1) is the height of the fixed step section 611 which is the ninth step from the bottom of the fixed screen member 61. matches the position.

As described above, when the actuator 655 shown in FIG. 3 is driven, the drive shaft 653, the first drive eccentric cam 6531, and the second drive eccentric cam 6532 rotate, and the first frame 651 and the second frame 652 rotate. do. In addition, following the rotation, the driven shaft 654, the first driven eccentric cam 6541, and the second driven eccentric cam 6542 also rotate in the same manner. As the first frame 651 and the second frame 652 rotate, the first operating screen member 62 and the second operating screen member 63 move in a circular orbit when viewed from the width direction between the fixed screen members 61. That is, the first operating screen member 62 and the second operating screen member 63 repeatedly move upward and downward with respect to the fixed screen member 61 while moving upstream and downstream.

(a2) and (b2) show the state when the drive shaft 653 is rotated 90 degrees from the states of (a1) and (b1). As shown in (a2), the first drive position 651a rotates with respect to the drive axis 653a, and the first operating screen member 62 moves upward with respect to the fixed screen member 61. Together with the first operating screen member 62, the foreign matter X1 is also moving upward with respect to the fixed stage 611 that is the ninth stage from the bottom. Further, as shown in (b2), the second drive position 652a rotates with respect to the drive axis 653a, and the second operating screen member 63 moves downward with respect to the fixed screen member 61. The foreign matter X2 is left behind on the fixed stage section 611, which is the ninth stage from the bottom. That is, the drive device 65 is moving the second operating screen member 63 downward while moving the first operating screen member 62 upward.

(a3) and (b3) show the state when the drive shaft 653 is further rotated by 90 degrees from the states of (a2) and (b2). As shown in (a3), the first movable screen member 62 has moved downstream with respect to the fixed screen member 61 and has moved exactly one step upward with respect to the fixed screen member 61 when viewed from the width direction. , and is at the first conveyance position overlapping the fixed screen member 61 except for the upper end portion and the lower end portion. In other words, the height position of the first operating step section 621 which is the ninth step from the bottom of the first operating screen member 62 shown in (a3) is the same as that of the fixed step section 611 which is the tenth step from the bottom of the fixed screen member 61. Matches the height position. Then, the foreign matter X1 is lifted up one step by the first operating screen member 62 and caught on the fixed step portion 611 which is the tenth step from the bottom of the fixed screen member 61. In this way, the foreign matter X1 caught in the first operating stage section 621 of the ninth stage is transferred to the fixed stage section 611 of the tenth stage by the movement of the first operating screen member 62. Further, as shown in (b3), the second movable screen member 63 moves upstream with respect to the fixed screen member 61, and when viewed from the width direction, the fixed screen member 61 and the second movable screen member 63 overlap. at the second initial position. That is, the drive device 65 moves the second operating screen member 63 upstream while the first operating screen member 62 is moving downstream. Further, as shown in (a1) and (b1) to (a3) and (b3), when the first operating screen member 62 is being moved toward the first conveyance position, the drive device 65 moves the second operating screen member 62 toward the first transport position. The screen member 63 is returned to the second initial position.

(a4) and (b4) show the state when the drive shaft 653 is further rotated by 90 degrees from the states of (a3) and (b3). As shown in (a4), the first movable screen member 62 is moving downward with respect to the fixed screen member 61. The foreign matter X1 is left behind on the fixed stage section 611, which is the tenth stage from the bottom. Further, as shown in (b4), the second operating screen member 63 is moving upward with respect to the fixed screen member 61. Together with the second operating screen member 63, the foreign matter X2 is also moving upward with respect to the fixed stage portion 611 that is the ninth stage from the bottom. That is, the drive device 65 is moving the second operating screen member 63 upward while moving the first operating screen member 62 downward.

(a5) and (b5) show the state when the drive shaft 653 is further rotated by 90 degrees from the states of (a4) and (b4). As shown in (a5), the first movable screen member 62 moves upstream with respect to the fixed screen member 61, and when viewed from the width direction, the fixed screen member 61 and the first movable screen member 62 overlap. . That is, the first operating screen member 62 shown in (a5) has returned to the same first initial position as in (a1). Further, as shown in (b5), the second movable screen member 63 moves downstream with respect to the fixed screen member 61 and moves upward by exactly one step relative to the fixed screen member 61 in the width direction. When viewed from above, it overlaps the fixed screen member 61 except for the upper and lower end portions. That is, the first operating screen member 62 shown in (b5) has returned to the same second transport position as in (b1). Further, as shown in (a3) and (b3) to (a5) and (b5), when the first operating screen member 62 is returning toward the first initial position, the drive device 65 is activated in the second operating screen member 62. The screen member 63 is being moved toward the second transport position.

For example, one cycle of driving the first operating screen member 62 from (a1) to (a5) and one cycle of driving the second operating screen member 63 from (b1) to (b5) shown in FIG. , is repeatedly carried out at a rate of about 13 cycles per minute during a predetermined operating period depending on the number of fixed step portions 611 of the fixed screen member 61, etc.

As explained above, during the operation period, the foreign substances X1 and X2 are transferred upward through the fixed step section 611 step by step on the upstream side of the screen body 60, and finally from the uppermost step section 612 to the downstream side. It slides down toward a chute (not shown) and is discharged outside the raw sludge contaminant removal screen device 6.

According to this embodiment, since the first operating screen member 62 and the second operating screen member 63 are configured to be moved upward and downward at different timings with different timings, the load on the drive of the drive device 65 is decreases. As a result, the raw sludge contaminant removal screen device 6 can be driven with less electric power. Further, since the rotational movement of the first operating screen member 62 and the second operating screen member 63 becomes smooth, vibration of the raw sludge contaminant removal screen device 6 can be suppressed. Moreover, in this embodiment, the drive device 65 moves the second operating screen member 63 downward while moving the first operating screen member 62 upward, and moves the second operating screen member 63 upward. During this time, the first movable screen member 62 is moved downward. Thereby, the weight of the first operating screen member 62 and the weight of the second operating screen member 63 can be offset, and the load on the driving device 65 is further reduced. In other words, when one of the first operating screen member 62 and the second operating screen member 63 is moving upward, the weight of the other acts as a force to assist the driving of the drive device 65. The load on driving 65 can be further reduced. Thereby, the raw sludge contaminant removal screen device 6 can be driven with less electric power. Further, since the balance of the load on the drive device 65 due to the weight of the first operating screen member 62 and the second operating screen member 63 is almost uniform, the rotational movement in the drive device 65 becomes smooth, and vibrations caused by driving are further reduced. . Furthermore, the first frame 651 and the second frame 652 are arranged with a gap in the width direction, and the operating area of the first operating screen member 62 and the operating area of the second operating screen member 63 do not overlap. , the configuration of the drive device 65 can be simplified.

The present invention is not limited to the embodiments described above, and various changes can be made within the scope of the claims. For example, in the above-described embodiment, the raw sludge contaminant removal screen device 6 and the scum contaminant removal screen device 7 provided in the raw sludge screen unit 2 were explained as examples, but the present invention It can be applied not only to treatment facilities but also to facilities that treat water such as industrial water and agricultural water. Further, in the above-described embodiment, the contaminant removal screen device installed in the water tank 5 has been described as an example, but the contaminant removal screen device may be installed in the wastewater flowing through the flow path. Further, although the driving device 65 has been described as an example in which the first operating screen member 62 and the second operating screen member 63 are moved in a circular orbit when viewed from the width direction, the drive device 65 can be moved in a polygonal manner such as rectangular movement using a link mechanism or the like. It may be configured to do so. Furthermore, in the present embodiment, the operating screen member is divided into two parts, the first operating screen member 62 and the second operating screen member 63, and driven with staggered timings for upward movement. The timing of upward movement may be staggered. In other words, if the upward movement timing of at least one of the plurality of operating screen members is different from the upward movement timing of the other operating screen members, all the operating screen members can be moved vertically at the same timing. The driving load can be reduced compared to when moving to However, the timing of moving each operating screen member upward is determined so that the driving load of the drive device 65 is uniform within one cycle, taking into account the total weight of each driving screen member and the frame that drives the driving screen member. If set, it is desirable because the power consumption reduction effect and vibration suppression effect will be further enhanced. In addition, in this embodiment, the first operating screen member 62 and the second operating screen member 63 are arranged separately on the right side of the tank and on the left side of the tank, but they are arranged above and below the raw sludge contaminant removal screen device 6. It may also be placed. Further, the fixed screen member 61, the first movable screen member 62, and the second movable screen member 63 may be arranged in any order. For example, the first movable screen member 62, the fixed screen member 61, the second movable screen member 63, A plurality of sets of the screen member 63 and the fixed screen member 61 may be arranged in this order in the width direction. Furthermore, in the present embodiment, the drive device 65 moves the first operating screen member 62 and the second operating screen member 63 upward and downward; The operating screen member 63 or the like may be moved by its own weight, and the drive device 65 may be moved only upward.

2 Screen unit for raw sludge 4 Screen unit for scum 5 Water tank 6 Foreign matter removal screen device for raw sludge 7 Foreign matter removal screen device for scum 61 Fixed screen member 62 First operating screen member 63 Second operating screen member 63
65 Drive device

Claims (4)

a plurality of fixed screen members provided at intervals;
A first operating screen member and a second operating screen member that transport contaminants upward by repeatedly moving upward and downward between the plurality of fixed screen members;
a drive device that moves the first operating screen member and the second operating screen member upward;
The driving device transmits driving force to a first frame that holds a plurality of the first operating screen members, a second frame that holds a plurality of the second operating screen members, and to each of the first frame and the second frame. and an actuator that drives the drive shaft, and by driving the first frame and the second frame, timing of the plurality of first operating screen members and the plurality of second operating screen members is provided. What is claimed is: 1. A contaminant removal screen device, characterized in that it shifts and moves upward. The first frame includes a pair of left and right first frame parts arranged at intervals in the width direction, and a first cross member that spans between the first frame parts and connects the first frame parts. It has
The plurality of first operating screen members are fixed to the first cross member,
The second frame includes a pair of left and right second frame portions arranged at intervals in the width direction, and a second cross member that spans between the second frame portions and connects the second frame portions. and
The foreign matter removal screen device according to claim 1, wherein the plurality of second movable screen members are fixed to the second cross member. A plurality of the fixed screen members are arranged side by side in the width direction,
The foreign matter removal screen device according to claim 2, wherein the first frame and the second frame are arranged with a gap in the width direction. It is characterized by comprising a flow dividing member that divides the received wastewater flowing toward the gap into a side where the first operating screen member is arranged and a side where the second operating screen member is arranged. The contaminant removal screen device according to claim 3.

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