JP4312053B2 - Aeration equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an aeration apparatus used for purification of sewage.
[0002]
[Prior art]
Conventionally, as disclosed in Japanese Patent Publication No. 61-38000 and Japanese Patent Publication No. 63-51760, an axial impeller connected to a shaft of a submersible motor is accommodated in an apparatus casing. An aeration apparatus is known in which a liquid to be treated such as sewage is sucked into a flow path by rotation of a vehicle and aeration is performed by supplying air to the liquid to be treated.
[0003]
As shown in FIG. 5, this type of aeration apparatus includes an apparatus casing 205 that partitions and forms a main body portion in which an impeller 203 is attached to a tip portion of a shaft 202 of a submersible motor 201 and a flow path 204 of a liquid to be processed. And an air supply pipe 206 for supplying air to the liquid to be processed in the flow path 204.
[0004]
During operation, the underwater motor 201 is driven to rotate the impeller 203. As a result, the liquid to be treated is sucked into the flow path 204 from above, stirred and mixed with the air supplied from the air supply pipe 206, and then discharged from the discharge port 207 opened in the horizontal direction.
[0005]
By the way, in general, a large amount of fiber such as hair is mixed in the liquid to be processed which is a processing target of the aeration apparatus. If such a fiber is entangled with the impeller 203 or the motor shaft 202, the load on the motor increases and the operating efficiency of the apparatus decreases. Therefore, in the conventional aeration apparatus, the impeller 203 is constituted by a cylindrical rotating body 209 and a blade 210 provided on the outer periphery of the rotating body 209, and the upper edge of the rotating body 209 and a mechanical seal bracket. By reducing the gap 213 between the motor 208 and the motor shaft 202, a foreign matter such as a fiber material is prevented from easily entering the inside of the rotary body 209, which is an attachment portion of the motor shaft 202.
[0006]
However, since the mechanical seal bracket 208 is a non-rotating body and the rotating body 209 is a rotating body, there is a possibility of causing wear or breakage when both are in direct contact. In particular, since the upper edge portion of the rotating body portion 209 has a small thickness, when the upper edge portion contacts the mechanical seal bracket 208, it is easily affected by wear. Therefore, there is a limit to reducing the gap 213 in order to reliably prevent contact between the two. For this reason, even though the entry of large foreign matters could be prevented, the entry of small foreign matters could not be prevented.
[0007]
However, even if only small foreign matter enters, if the foreign matter accumulates inside the rotary body 209, it eventually becomes a large foreign matter 211. For this reason, it has been difficult to avoid a decrease in the operating efficiency of the apparatus.
[0008]
In addition, even if it does not enter the inside of the rotating body 209, foreign matter may be caught in the gap 213. However, if the impeller 203 rotates while foreign matter is sandwiched between the mechanical seal bracket 208 and the rotary body 209, there is a risk that the operating efficiency may be reduced and the impeller 203 and the mechanical seal bracket 208 may be worn or damaged.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above points, and an object of the present invention is to provide a highly reliable aeration apparatus by preventing the entanglement of foreign matter on a motor shaft or the like.
[0010]
[Means for Solving the Problems]
An aeration apparatus according to the present invention includes a motor having a motor shaft, a substantially cylindrical rotating body portion that is attached to the motor shaft and extends parallel to the axial direction of the motor shaft so as to cover an outer peripheral portion of the motor shaft. An impeller having blades provided on an outer peripheral portion of the rotating body, and a casing for partitioning and forming a flow path for stirring and mixing the liquid to be processed sucked by rotation of the impeller with a predetermined gas; and An end of the rotating drum portion facing the upstream side of the flow channel upstream of the rotating drum portion so as to close an end portion of the rotating drum portion on the upstream side of the flow channel, and arranged in a non-contact state with the rotating drum portion. a fixed portion having a larger outer diameter than the rotating barrel as a step is formed between the surface, attached to the front SL on the outer peripheral surface of the fixed portion, between said fixing portion rotating barrel The annular gap formed in the Has a shield portion that covers the outer side of the body portion, a portion of the shield portion is provided with a sliding contact shield member on the outer peripheral surface of the rotating barrel.
[0011]
According to the aeration apparatus, since the gap between the fixed portion and the rotating body is covered with the shield member, foreign matter does not enter the inside of the rotating body through the gap. For this reason, the entanglement of foreign matter on the motor shaft and the like, and the foreign matter being caught in the gap are prevented, and the reduction in operating efficiency is prevented. Further, since the shield part of the shield member is in sliding contact with the outer peripheral surface of the fixed part or the rotary body part, wear of the fixed part and the rotary body part is reduced.
[0012]
The aeration apparatus is formed in a substantially cylindrical shape extending in parallel with the rotating body of the impeller, and a motor cover that covers the motor, and a support arm that extends radially outward from the motor cover and supports the motor cover. The fixing portion is provided between the motor cover and the impeller, and the support arm is positioned on the suction side of a flow path of the liquid to be processed and formed by the casing, and the rotation The distance L between the end surface of the body portion on the motor cover side and the end surface of the support arm on the rotating body portion side may be set to 50% or less of the outer diameter of the rotating body portion.
[0013]
When the support arm is provided on the suction side of the flow path, the flow of the liquid to be processed sucked into the flow path is affected by the support arm. As a result, the pressure fluctuation of the liquid to be processed occurs, and the liquid to be processed easily enters the inside of the rotating body. However, according to the aeration apparatus, the entry of the foreign matter contained in the liquid to be treated is blocked by the shield member, so that the entry of the foreign matter is reliably prevented despite the support arm being provided. If the distance between the end surface on the motor cover side of the rotating body and the end surface on the rotating body side of the support arm is 50% or less of the outer diameter of the rotating body, it is particularly susceptible to the influence of the support arm. According to the aeration apparatus, the entry of foreign matter is reliably prevented.
[0014]
The aeration apparatus is formed in a substantially cylindrical shape extending in parallel with the rotating body of the impeller, and a motor cover that covers the motor, and a support arm that extends radially outward from the motor cover and supports the motor cover. The fixing portion is provided between the motor cover and the impeller, and the support arm is located on a suction side of a flow path of the liquid to be processed that is defined by the casing. The width of the arm in the direction orthogonal to the flow direction of the liquid to be processed may be set to 20 mm or more.
[0015]
As the width of the support arm is larger, the flow of the liquid to be processed sucked into the flow path is more easily influenced by the support arm, and the liquid to be processed is more likely to enter the rotating body. In particular, when the width of the support arm is 20 mm or more, the liquid to be processed easily enters the inside of the rotating body. However, according to the aeration apparatus, the entry of foreign matter contained in the liquid to be treated is blocked by the shield member, so that the entry of foreign matter is reliably prevented.
[0016]
The peripheral speed of the outer peripheral part of the rotating body part of the impeller in the aeration apparatus may be set to 3 m / s or more.
[0017]
As the rotation speed of the rotating body portion increases, the liquid to be processed enters the inside of the rotating body portion more easily. However, according to the aeration apparatus, the entry of foreign matter contained in the liquid to be treated is blocked by the shield member, so that the entry of foreign matter is reliably prevented.
[0018]
As described above, according to the present invention, since the shield member that covers the gap between the fixed part and the rotary body part and is in sliding contact with the outer peripheral surface of the fixed part or the rotary body part is provided, It is possible to prevent foreign matter from entering the inside of the rotating body without causing damage to the body. Therefore, the entanglement of foreign matters on the motor shaft or the like can be prevented, and the reliability of the apparatus can be improved.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0020]
As shown in FIG. 1, the aeration apparatus 20 is a so-called underwater mechanical aeration apparatus, and sucks liquid to be processed from above by rotation of an impeller 8 connected to a shaft 13 of the motor 2, and passes through an air supply pipe 11. The supplied air is agitated and mixed with the liquid to be treated and discharged from the lower discharge port 15.
[0021]
-Configuration of aeration device-
First, the configuration of the aeration apparatus 20 will be described. The device casing 102 of the aeration device 20 is formed by mounting and fixing the suction casing 9 on the discharge casing 10. The suction casing 9 is formed in a substantially cylindrical shape, and is widened toward the upper opening in order to smoothly suck the liquid to be processed. A flange 31 serving as a connection portion with the discharge casing 10 is provided on the outer periphery of the lower opening of the suction casing 9. The upper end of the discharge casing 10 opens concentrically with the lower opening so as to be smoothly continuous with the lower opening of the suction casing 9, and a flange 32 that contacts the flange 31 is formed on the outer periphery thereof. The suction casing 9 and the discharge casing 10 are fixed by fastening the flange 31 and the flange 32 with bolts (not shown). Thus, the inner surface of the apparatus casing 102 is formed in the circumferential surface. The apparatus casing 102 is a casing that partitions and forms a flow path 16 that discharges the liquid to be treated sucked by the rotation of the impeller 8 with stirring and mixing with a predetermined gas.
[0022]
A flat portion 33 having an insertion hole 34 for the air supply pipe 11 at the center is formed at the bottom of the discharge casing 10, and a part of the periphery of the flat portion 33 is an inner side inclined downward toward the outside. A slope 35 is formed. A discharge port 15 is formed between the inner inclined surface 35 and an outer frame portion inclined in the same manner as the inner inclined surface 35. As described above, the flow path 16 is formed in the apparatus casing 102 so that the liquid to be processed sucked from above through the suction port 14 is discharged from the discharge port 15 in a substantially horizontal direction by changing the flow direction. Yes.
[0023]
An air supply pipe 11 connected to a blower (not shown) as an air supply source is connected to the flat portion 33 of the discharge casing 10. The air supply pipe 11 passes through the insertion hole 34, and the opening protrudes upward from the lower end surface of the discharge casing 10. The opening of the air supply pipe 11 is opposed to the upper surface of the air chamber casing 12 that partitions the air chamber 17 and the flow path 16 with a predetermined interval. The air chamber casing 12 defines the air chamber 17 for once supplying air supplied from the air supply pipe 11 and supplying the air to the flow path 16 evenly. The side surface of the air chamber casing 12 is inclined along the inner inclined surface 35 of the discharge casing 10, and the air in the air chamber 17 is supplied to the liquid to be treated in the flow path 16 and stirred and mixed at the lower end thereof. A supply path 18 is formed. The air chamber casing 12 also serves as a diffuser that guides the liquid to be processed toward the discharge port 15.
[0024]
A drive unit 101 is provided on the upper part of the apparatus casing 102 to apply a driving force for sucking and stirring the liquid to be processed. The drive unit 101 is configured by assembling a motor casing 1, a motor 2 housed in the motor casing 1, a shaft 13 of the motor 2, an oil casing 3, a mechanical seal bracket 7, an impeller 8, and the like. The motor casing 1 and the oil casing 3 constitute a motor cover that covers the motor 2. The mechanical seal bracket 7 constitutes a fixed portion as referred to in the present invention.
[0025]
The motor casing 1 is formed in a substantially cylindrical shape whose upper side is closed, and a motor chamber 40 is defined in the inside thereof.
[0026]
The motor 2 includes a cylindrical stator 2a fixed to the inner wall of the motor casing 1, and a rotor 2b disposed concentrically with the stator 2a inside the stator 2a. A shaft 13 extending downward is fixed to the inner peripheral surface of the rotor 2b. The shaft 13 is rotatably supported by an upper bearing (not shown) and a lower bearing 4 housed in the upper part of the oil casing 3.
[0027]
A shaft 13 passes through the center of the oil casing 3 that defines the oil chamber 25. The lower bearing 4 that supports the shaft 13 is held by a step portion of the oil casing 3. The lower end of the outer peripheral portion 21 of the oil casing 3 is fixed to the outer peripheral portion 22 of the mechanical seal bracket 7. On the other hand, the lower end of the inner peripheral portion 23 of the oil casing 3 is connected to the inner peripheral portion 24 of the mechanical seal bracket 7 via the mechanical seal 6. As a result, the oil casing 25 and the mechanical seal bracket 7 define an oil chamber 25 that supplies oil as a lubricant to the mechanical seal 6 that is the shaft seal portion of the shaft 13. The motor chamber 40 is sealed by the oil casing 3 so that the liquid to be processed does not enter the motor chamber 40.
[0028]
The motor casing 1 and the oil casing 3 are fastened by bolts (not shown). Therefore, the oil casing 3 fixedly supports the motor casing 1 and supports the shaft 13 via the lower bearing 4 so as to be rotatable.
[0029]
An impeller 8 is fastened to the tip of the shaft 13. The impeller 8 includes a substantially cylindrical hub (rotary body) 36 that extends in parallel with the shaft 13, and a plurality of blades 37 that protrude from the outer peripheral surface of the hub 36. The hub 36 is provided with a shaft mounting arm 36a extending toward the center thereof. The shaft 13 is inserted into the mounting hole of the mounting arm 36a and fastened. Thereby, the impeller 8 rotates according to the rotation of the shaft 13, and a suction force that guides the liquid to be processed from the upper side to the lower side is generated. The impeller 8 rotates at a rotational speed such that the peripheral speed of the outer peripheral surface of the hub 36 is 3 m / s or more.
[0030]
The drive unit 101 and the device casing 102 are fixed via the mounting arm 5. The mounting arm 5 is a support arm that supports the drive unit 101. As shown in FIG. 2, in this embodiment, three mounting arms 5 are provided at equal intervals in the circumferential direction. One end of the mounting arm 5 is fixed to the upper end portion 41 of the suction casing 9, and the other end is fixed to the oil casing 3. The mounting arm 5 is located above the suction port 14 of the suction casing 9. That is, the mounting arm 5 is located on the suction side of the flow path 16 for the liquid to be processed. The width b of the mounting arm 5 is set to 20 mm or more.
[0031]
As shown in an enlarged view in FIG. 3, a shield ring 50 is fixed to the outer peripheral surface of the mechanical seal bracket 7. The shield ring 50 is an annular shield member that covers an annular gap 60 formed between the mechanical seal bracket 7 and the hub 36 from the outside, and an attachment portion that is attached to the outer peripheral surface of the mechanical seal bracket 7 by the fixing metal 54. 53 and a shield part 51 extending from the attachment part 53 to the hub 36 side. In the present embodiment, since the outer peripheral surface of the hub 36 is located on the inner side of the outer peripheral surface of the mechanical seal bracket 7, the shield portion 51 of the shield ring 50 is inclined inward.
[0032]
The inner diameter of the tip 52 of the shield part 51 is slightly smaller than the outer diameter of the hub 36. The tip 52 of the shield 51 is in contact with the outer peripheral surface of the hub 36, and the cross-sectional shape of the tip 52 is formed in an arc shape so that the sliding contact with the hub 36 is smooth as shown in FIG. Has been. However, the cross-sectional shape of the tip portion 52 of the shield portion 51 is not limited to an arc shape, and may be another curved shape. Moreover, the rectangular shape which has a certain large sliding contact area may be sufficient. In order to reduce wear on the outer peripheral surface of the hub 36, the shield ring 50 is made of rubber.
[0033]
The distance L between the lower surface of the mounting arm 5 and the upper end surface of the hub 36 is set to 50% or less of the outer diameter of the hub 36.
[0034]
-Operation of the aeration device-
During the operation of the aeration apparatus 20, the motor 2 is driven, and the impeller 8 rotates according to the rotation of the shaft 13. By the rotation of the impeller 8, the liquid to be processed is sucked obliquely downward with respect to the flow path 16 through the suction port 14. And the to-be-processed liquid distribute | circulates the inside of the flow path 16 at a speed | rate of about 2-3 m / s. On the other hand, the air supplied from the blower (not shown) through the air supply pipe 11 is discharged into the air chamber 17 and then stirred and mixed with the liquid to be processed in the flow path 16 through the supply path 18. The mixed liquid containing bubbles flows through the flow path 16 while changing the flow direction from the downward direction to the horizontal direction, and is discharged from the discharge port 15 in the substantially horizontal direction.
[0035]
-Effects of this embodiment-
According to the present aeration apparatus 20, since the gap 60 between the mechanical seal bracket 7 and the hub 36 is covered by the shield ring 50, the fiber (foreign matter) such as hair is prevented from entering the inside of the hub 36. can do. Since the shield portion 51 of the shield ring 50 is brought into contact with the outer peripheral surface of the hub 36, entry of foreign matter can be reliably prevented.
[0036]
In particular, in the present aeration apparatus 20, the mounting arm 5 for supporting the drive unit 101 is provided above the mechanical seal bracket 7, so that the liquid to be treated on the downstream side of the mounting arm 5 is disturbed. The pressure is likely to change. Therefore, if the shield ring 50 is not provided, a part of the liquid to be processed easily moves in and out of the hub 36 through the gap 60 due to such pressure imbalance. However, since the aeration apparatus 20 includes the shield ring 50, the flow of the liquid to be processed in the gap 60 can be prevented. Therefore, although the mounting arm 5 is provided above the mechanical seal bracket 7, it is possible to reliably prevent foreign matter from entering the hub 36.
[0037]
The shield part 51 of the shield ring 50 is in contact with the outer peripheral surface of the hub 36, and the tip part 52 of the shield part 51 is formed in a curved surface shape and has a relatively large contact area. The shield ring 50 is made of rubber. Therefore, wear of the hub 36 is reduced.
[0038]
The shield ring 50 is attached to the mechanical seal bracket 7 by a fixing metal 54. Therefore, attachment and removal are easy and can be easily replaced.
[0039]
-Modification-
Upper Symbol embodiment is impeller 8 to the motor 2 is a direct form, may be provided a reduction gear between the motor 2 and the impeller 8.
[0040]
The gas supplied to the liquid to be treated is not limited to air, but may be other gas, for example, another oxygen-containing gas.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a part of an aeration apparatus according to an embodiment.
FIG. 2 is a plan view of the aeration apparatus.
FIG. 3 is an enlarged sectional view showing a part of the aeration apparatus.
FIG. 4 is a cross-sectional view of a shield ring.
FIG. 5 is a sectional view showing a conventional aeration apparatus with a part thereof cut away.

Claims (4)

A motor having a motor shaft;
A substantially cylindrical rotating body portion that is attached to the motor shaft and extends parallel to the axial direction of the motor shaft so as to cover the outer periphery portion of the motor shaft, and a blade provided on the outer periphery portion of the rotating body portion An impeller having,
A casing for partitioning and forming a flow path for stirring and mixing the liquid to be treated sucked by rotation of the impeller with a predetermined gas; and
An end of the rotating drum portion facing the upstream side of the flow channel upstream of the rotating drum portion so as to close an end portion of the rotating drum portion on the upstream side of the flow channel, and arranged in a non-contact state with the rotating drum portion. A fixed portion having an outer diameter larger than that of the rotating body so that a step is formed between the surface and the surface ;
A shield part that is attached on an outer peripheral surface of the fixed part and covers an annular gap formed between the fixed part and the rotary body part from the outside of the rotary body part; A shield member that is in sliding contact with the outer peripheral surface of the rotating body portion;
An aeration apparatus comprising: The aeration apparatus according to claim 1,
A motor cover that is formed in a substantially cylindrical shape extending in parallel with the rotating body of the impeller, and covers the motor;
A support arm that extends radially outward from the motor cover and supports the motor cover;
The fixing portion is provided between the motor cover and the impeller.
The support arm is located on the suction side of the flow path of the liquid to be processed that is partitioned by the casing,
An aeration apparatus in which a distance L between an end surface of the rotating body portion on the motor cover side and an end surface of the support arm on the rotating body portion side is set to 50% or less of an outer diameter of the rotating body portion. The aeration apparatus according to claim 1,
A motor cover that is formed in a substantially cylindrical shape extending in parallel with the rotating body of the impeller, and covers the motor;
A support arm that extends radially outward from the motor cover and supports the motor cover;
The fixing portion is provided between the motor cover and the impeller.
The support arm is located on the suction side of the flow path of the liquid to be processed that is partitioned by the casing,
The aeration apparatus in which the width of the support arm in the direction orthogonal to the flow direction of the liquid to be treated is set to 20 mm or more. The aeration apparatus according to claim 1,
The aeration apparatus in which the peripheral speed of the outer peripheral portion of the rotating body of the impeller is set to 3 m / s or more.

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