KR20030061703A - The eddy current coupling variable speed brake of a centrifuge screw decanter - Google Patents

Abstract

PURPOSE: Provided is a decanter-typed centrifugal separator with an automatic brake which converts braking power of a differential pulley to eddy current coupling of the automatic brake so that it helps to reduce consumption power of the drive motor. CONSTITUTION: The decanter-typed centrifugal separator with the automatic brake comprises the parts of: a drive pulley(5) which is connected to a drive motor(4) by a belt and assembled to a main rotation axis; a ball recovery pulley(6) which is connected to the drive pulley; a pipe(7) for supply liquid which supplies material to an external bowl(3); a screw conveyer(8) which is connected to the pipe for supply liquid to transfer solids to the inside of the external bowl; a releasing hole(9) for supply liquid which is formed at one side of the screw conveyer; a releasing bushing(10) for solids which is formed at the external bowl; releasing holes(12,13) for separation liquid and solids which are formed at both lower sides of a casing(11); a dam flange(14) which is formed at one side of the external bowl; a differential pulley(17) which is connected to a generation axis(15) for gear box; and the automatic brake(18) which is placed under the gear box.

Description

Decanter type centrifuge with automatic braking system {The eddy current coupling variable speed brake of a centrifuge screw decanter}

The present invention is a centrifugal dehydrator and concentrator (hereinafter referred to as "centrifuge") that separates sludge generated in a wastewater treatment process into water and solids, and the braking force of the differential pulley is rotated through the eddy current coupling of the automatic transmission brake. It reduces power consumption of the driving motor by converting it into power, and automatically controls the vehicle speed according to the property and concentration load of the processed material. The present invention relates to a decanter type centrifuge with an automatic transmission braking device for safe handling.

In general, the speed control device of the centrifugal separator used in the prior art uses a planetary gear reducer or a cyclone reducer to obtain a fixed rotor wheel, and the pulley is fixed to the sun gear on one side of the reducer and then connected to the AC motor and belt. The rotational speed of the inner screw is made smaller than the outer rotational speed, and the transfer speed current value of the AC motor is transferred to the inverter according to the properties of the input and the concentration variable. It was consisted of controlling AC motor by sensing and arbitrarily controlling the rotation speed of AC motor.

Therefore, such a conventional method is not only able to obtain a constant sludge concentration and water content of the separated solids in the continuous separation, concentration, and dehydration of water and solids, but also could not operate safely and consumes a lot of power costs.

In addition, the fixing of the wheels does not achieve the process of concentration and dehydration at the same time in one process, and the process of concentration and dehydration must proceed separately, there was a problem in that to adjust the wheels in progress of these processes.

On the other hand, there is a method of braking by eddy current by attaching an eddy current brake to the sun gear on one side of the gearbox, but in the above case, the braking force is released as heat due to slip between the inductor and the drum. Power consumption had many problems.

In addition, a low speed high torque hydraulic motor is mounted on the rotating body instead of a gearbox, and a high pressure hydraulic oil is supplied from the hydraulic pump to rotate the screw conveyor. However, in this case, the manufacturing cost of the high pressure hydraulic motor and the hydraulic pump was high. In addition, there was an uneconomical problem of excessive cost due to regular replacement work due to oil leakage at the rotary joint part that supplies high pressure hydraulic pressure to the high speed rotating body.

The present invention has been made in order to solve the problems of the prior art as described above, the object of the present invention is to control the rotational speed of the outer copper bowl and inner copper screw with less power in the process of condensation and dehydration of water and discharged solids Concentration and dehydration are achieved at the same time, and the braking power of the differential pulley is converted to the rotational power of the externally driven ball through the eddy current coupling of the automatic transmission braking device according to the characteristics and concentration load of the treatment to achieve variable speed. The present invention provides a decanter type centrifuge with an automatic transmission braking device that can safely treat dehydrated objects with a constant separation liquid and discharged solids.

1 is a cross-sectional view of a decanter centrifuge (centrifugal dehydrator and concentrator) equipped with an automatic transmission brake device.

2 is a partial cross-sectional view of an automatic transmission braking device

Figure 3 is an automatic vehicle speed control system diagram of a decanter centrifuge with an automatic transmission brake.

Figure 4 is a graph of braking power consumption and recovery power of a decater-type centrifuge with an automatic transmission brake.

* Explanation of symbols for main parts of the drawings

4: driving motor 5: driving pulley

6: bowl regenerative pulley 8: screw conveyor

11: outer casing 15: gearbox output shaft

16 gearbox 17 differential pulley

18: automatic transmission braking device 23: braking speed detector

24: female coil 25: inductance 26: drum

Hereinafter, a temporary embodiment of the eddy current coupling shift braking apparatus of the present invention decanter centrifuge will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional configuration diagram showing the overall configuration of a centrifugal separator with an automatic transmission braking apparatus according to the present invention, Figure 2 is a partial cutaway cross-sectional configuration diagram of the automatic transmission braking apparatus according to the present invention,

3 is a diagram of a vehicle speed control system of a decanter centrifuge with an automatic transmission brake according to the present invention, and FIG. 4 is a graph showing braking power consumption and recovery power of the automatic transmission brake according to the present invention. The braking power consumption of the centrifuge with the automatic transmission braking device of the present invention, the solid line represents the braking power consumption of the existing technology.

1 to 2, the outer movable balls 3 are rotatably supported on the bearings on both upper sides of the base frames 2 and 2a fixed to the ground by the dustproof parts 1 and 1a, respectively. In addition, the drive motor 4 and the drive pulley 5 connected to the belt are assembled on the main rotation shaft, and the bowl regenerative pulley 6 and the drive pulley 5 are constantly connected to rotate at the same speed.

In addition, a screw conveyor (8) for conveying solids is mounted on the inner circumference of the cylindrical outer bowl (3) so as to communicate with the feed pipe (7), and the feed along the circumference at a predetermined portion of the screw conveyor (8). The feed liquid discharge port 9 for ejecting the water is formed to be through the inside.

In addition, a solid discharge bushing 10 is formed at the inclined angle of the cone of the outer bowl 3, the outer bowl 3 is supported by the base frame (2) (2a) while being protected by the outer casing (11), On both sides of the bottom of the casing 11, a separation liquid discharge port 12 and a solid discharge port 13 are formed.

On the other hand, the one side of the outer bowl (3) is formed with a dam flange 14 for discharging the separation liquid, the screw conveyor (8) is connected to the gearbox output shaft 15, the output shaft again the gearbox (16) A brake input belt 21 connected to the differential pulley 17 and below the gearbox 16 is provided with an automatic transmission braking device 18 connected to both of the brake input pulleys 19 and the brake output pulley 20. It is connected to the differential pulley 17 and the bowl regenerative pulley 6 through the braking output belt 22, respectively.

Here, the brake input shaft 28 and the brake output shaft 29 are installed on both sides of the automatic transmission braking device 18 to be connected to the brake input pulley 19 and the brake output pulley 20, respectively, and the braking speed therein. A detector 23, an excitation coil 24, an inductor 25, and a drum 26 are installed in this order. Such a braking device is configured to be supported by the braking device frame 27.

Unexplained code in the drawing

30 is the rotational speed input

31, vehicle speed control controller

32, braking rotational speed input

Reference numeral 33 denotes an excitation current output.

Referring to the operation example of the decanter centrifuge according to the present invention as follows.

First, when power is applied to the driving motor 4, the outer bowl 3 rotates at a constant speed of the set rotation ratio of the driving pulley 5 to generate centrifugal force, and at the same time, the screw conveyor 8 moves to the outer bowl 3 It is supported by a bearing inside the through the gearbox output shaft 15 and the gearbox 16 is connected to the differential pulley 17, the differential pulley 17 tries to rotate at the rotational speed of the outer bowl (3). At this time, the excitation current output 33 signal is transmitted to the excitation coil 24 by the vehicle speed control set values inputted to the automatic transmission braking device 18 and the vehicle speed control controller 31 so that the external bowl 3 and the screw conveyor 8 ) And the differential pulley (17) rotates later than the rotation speed of the outer bowl (3) so that the forward rotation load does not occur, but the reverse rotation load (hereinafter referred to as the brake load) The vehicle speed represents the rotation speed of the solids conveyance of the screw conveyor 8 on the basis of the outer bowl 3, and the formula is as follows.

Vehicle speed = (outer bowl speed-differential pulley speed) ÷ gearbox reduction ratio

In this state, the feed flows into the feed liquid outlet 9 of the screw conveyor 8 which is operated in the forward rotation through the feed liquid pipe 7, and is dispersed in the outer bowl 3 by the centrifugal force of the rotating bowl 3. When separated into light supernatant and heavy solids at

The light supernatant flows into the outer bowl 3 and flows through the spiral channel of the screw conveyor 8 to overtake the dam flange 14 on the side of the outer bowl 3 so as to separate the outlet 12 of the outer casing 11. Through the separation liquid

Heavy solids are settled outside the outer bowl (3) and transferred to the inclined angle by the screw conveyor (8) rotated and transported, and concentrated and dehydrated by the centrifugal force and the pressing force of the screw conveyor (8). It is discharged through 13).

In this case, the vehicle speed should be changed automatically according to the change of the solid concentration of the feed to obtain the desired concentration of the discharged solid in the concentration and dehydration process. In other words, the concentration process is usually about 3-8% suitable for the post-stage process. The concentration of the discharged solids in the process, and in the dehydration process, increase the concentration of the discharged solids as much as possible.

By reducing the amount of waste solids that have to be disposed of last, the costs of incineration, landfilling and dumping at sea are reduced.

On the other hand, if the concentration of the solids supplied is constant, the desired velocity of the concentrated and dehydrated solids can be continuously obtained while the vehicle speed is fixed, but the sludge generated in the wastewater treatment process is sludge depending on the characteristics of the process, season, time and operation method. The concentration of solids in the mixture changes continuously.

Thus, even if the concentration of solids in the feed changes, the vehicle speed is adjusted so that the discharged solids can be stably obtained. If the vehicle speed is slow, the settled solids increase in residence time in the outer bowl (3) and the concentration of the discharged solids increases. This method uses the principle that the solids have a low residence time in the outer bowl (3) and the concentration of the discharged solids is lowered.If the concentration of the feeds is high at a constant flow rate of the input feed, the sedimented solids accumulate inside the vehicle. This speeds up, and if the feed concentration is low, the vehicle speed can be slowed down to obtain the desired solids concentration of the solid.

Here, the key technical point of the present invention is related to the vehicle speed control which makes the concentration of discharged solids stable and constant even if the concentration of the supplied solids changes.

Referring to FIG. 2 and FIG. 3 with respect to the automatic transmission braking device, when the driving motor 4 applies power to give the driving pulley 5 a rotary motion, the driving load received by the driving motor 4 is externally driven. The force for rotating the bowl (3) and the settled solids are divided into the forces for the screw conveyor (8) to transport the solids discharge bushing (10), and the force for transporting the solids is an external bowl connected to the screw conveyor (8). When the differential pulley 17 is transmitted to the differential pulley 17 which rotates later than the rotation of the (3), the differential pulley 17 generates a force to rotate at the rotational speed of the external bowl 3 by the solid conveying load on the screw conveyor 8 and When the differential pulley 17 rotates at the rotational speed of the outer bowl 3, as shown in the above vehicle speed formula, the vehicle speed becomes zero, so that the screw conveyor 8 loses the rotation difference and solids are not transferred.

Therefore, the differential pulley 17 should always rotate later than the number of revolutions of the outer bowl 3 during normal operation,

The automatic transmission braking device 18 serves to brake the differential pulley 17 to make a late rotational movement, and at the same time adjust the rotation speed of the differential pulley 17 to change the vehicle speed, and The braking power is converted into rotational power of the outer bowl 3 through the bowl regenerative pulley 6 to reduce the power consumption of the driving motor 4.

That is, the operation and principle of the automatic transmission braking device 18 transfers the braking force generated by the differential pulley 17 to the braking input belt 21, the braking input pulley 19, the braking input shaft 28, and the inductor 25. The non-contact drum 26 of the type in which the inductor rotates by the pulley ratio of the differential pulley 17 and the braking input pulley 19 and surrounds the inductor on the outer periphery has a braking output shaft 29 and a braking output pulley ( 20), connected to the braking output belt 22 and the bowl regenerative pulley (6) at a rate later than the speed of the outer bowl (3) set by the pulley ratio of the braking output pulley (20) and the bowl regenerative pulley (6). Make a constant rotation.

On the other hand, the rotational speed of the inductance 25 as shown in the graph of Figure 4 is

The rotation of the outer bowl (3) and the pulley ratio of the differential pulley (17) and the braking input pulley (19) rotates at a maximum of 2200 rpm, and the drum rotates with the outer bowl (3) and the braking output pulley (20). When fixed and rotated at 1500 rpm set by the pulley ratio of the bowl regenerative pulley 6, the inductor 25 and the drum 26 adjust the pulley ratio to rotate at a deviation of 700 rpm,

At this time, when a direct current excitation current flows through the excitation coil 24, magnetic flux flows between the inductor 25 and the drum 26 and an eddy current is generated, thereby generating an electromagnetic force between the inductor 25 and the drum 26. Since the torque is generated by the interaction between the 25 and the drum 26, the inductor 25 and the drum 26 are eddy current coupling because power is transmitted to rotate in the same direction.

At this time, if a lot of direct current of the excitation coil 24 flows a lot of power transmission, the rotation of the inductor 25 is equal to the rotation of the drum 26, the rotational speed of the inductor 25 reaches 1500rpm, the direct current Reducing the power transmission reduces the slip between the inductor 25 and the drum 26, the inductor 25 rotates up to 2200rpm, so the rotation of the inductor 25 is braking shifted from 2200rpm to 1500rpm to differential pulleys (17). The vehicle speed of the screw conveyor 8 is converted by adjusting the rotation speed of the screw conveyor 8.

In addition, the braking power becomes the rotational power of the inductor 25 and rotates the drum 26 at 1500 rpm to be applied as the bowl rotational power through the bowl regenerative pulley 6 to reduce the consumption power by the applied power, and the inductor 25. And drum 26 are connected to each other in the opposite direction even when installed to exhibit the same performance.

Here, with reference to Figure 3 will be described in more detail with respect to the vehicle speed control using the automatic transmission braking device 18,

The conveying load of the settled solids of the screw conveyor 8 is transmitted to the inductor 25 with braking force and rotates. At this time, the vehicle speed control controller 31 compares the bowl rotational speed input 30 and the braking rotational speed input 32 to detect the vehicle speed, and compares and calculates the excitation current output 33 and the braking rotational speed input 32. Detects braking torque.

At this time, the braking torque is proportional to the slip amount which is a deviation between the excitation current output 33 and the braking rotational speed input 32, and when the braking torque to be operated is set in the vehicle speed control controller 31, the braking torque increases and the excitation is increased. PID control is continuously performed in the direction of increasing the braking torque by lowering the braking torque by increasing the exciting current output 33 to the coil 24 to speed up the vehicle speed and decreasing the braking torque when the braking torque is reduced. To control the vehicle speed.

In detail with reference to Figure 4,

In terms of

When the eddy current coupling torque 4㎏- m is used and the braking device output shaft rotation speed is 1500 RPM,

Is recovered by the rotational power of the external copper.

As described above, the present invention is stable and smoothly made in response to the concentration change of various sludges generated in the wastewater treatment process, and has a continuous treatment process by automatic operation, thereby improving the treatment efficiency. Of course, it is a very useful invention to smoothly control the vehicle speed while significantly reducing the power consumption of the drive motor.

Claims (2)

On both sides of the upper part of the base frame (2) (2a), which is fixed to the ground by the dustproof part (1) (1a), the outer motor (3) is rotatably supported on the bearings, respectively, to the drive motor (4) and the belt. The driving pulley 5 to be connected is assembled to the main shaft, The bowl regenerative pulley 6 and the drive pulley 5 are rotated at a constant speed at the same speed, and the feed liquid pipe so that the feed flows into the inside of the outer bowl 3 to one side of the drive pulley 5. 7) is mounted, a screw conveyor (8) for conveying the solids is mounted in communication with the feed liquid pipe (7) on the inner circumference of the outer bowl (3) of the cylinder, The predetermined portion of the screw conveyor (8) is formed so that the feed solution outlet (9) is formed through the inside, the inclined angle of the outer bowl (3) is formed solid discharge bushing (10), the outer bowl (3) is supported by the base frame (2) (2a) while being protected by the outer casing (11), the separation liquid outlet (12) and solids outlet (13) is formed on both sides of the bottom of the casing (11) The one side of the outer bowl (3) is formed with a dam flange 14 for discharging the separation liquid, the screw conveyor (8) is connected to the gearbox output shaft 15, the output shaft again passes through the gearbox (16) In the centrifugal separator connected to the differential pulley 17, an automatic transmission braking device 18 is attached to the gear box 16 to control the rotation speed of the differential pulley 17 to cope with changes in the properties and concentrations of the processed material. The vehicle speed is automatically changed and the braking force generated by the differential pulley (17) Decanter-type centrifuge with automatic transmission braking device characterized in that it reduces the power consumption by converting to rotational power. 2. The vehicle speed control controller 31 according to claim 1, wherein a braking speed detector 23, an excitation coil 24, an inductor 25, a drum 26, and the like are installed inside the automatic transmission braking device 18. A decanter centrifuge with an automatic transmission brake, characterized in that for executing control.