JPH05321227A - Dust remover - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a dust remover that performs an emergency stop only when a large amount of dust flows in and the load torque exceeds a predetermined set torque and this state continues for a certain period. [Structure] The dust limiter is equipped with a torque limiter that sends a signal when the load torque of the power unit exceeds the set torque.
Emergency stop circuit Y ₂ that issues a stop command to the power unit (power circuit X) when an overload torque exceeding the set torque during operation continues for a preset time or more in the operating circuit Y of the power unit
Was granted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust remover for removing dust from seawater or river water, and in particular, an emergency stop means for protecting equipment and power equipment during severe operating conditions in which overload torque continues. The present invention relates to a dust removing device.

[0002]

2. Description of the Related Art Conventionally, generally used dust removers are widely used in industrial water canals or water canals for collecting cooling water in power plants. A link chain is provided on both sides, and a bar screen or a wire mesh screen is erected perpendicularly or almost perpendicularly to the flow direction for each link of this link chain, and the dust caught on the screen is rotated by rotating it. There is a structure to remove it outside the waterway.

3 to 6 show an embodiment of a conventional dust removing device, FIG. 3 is an overall schematic view, and FIGS. 4 and 5 are a detailed vertical sectional view and a front view of a screen frame having a bucket portion. Further, FIG. 6 is a torque curve diagram showing a temporal change in the load torque received by the power plant during operation.

In FIG. 3, 1 is an upper sprocket wheel, 2 is a lower sprocket wheel, 3 is a link chain mounted endlessly on both sprocket wheels 1 and 2, and 4 is attached to a link chain 3 and captured by the lower part. A screen frame having a bucket portion for storing dust, 5 is a power unit for transmitting power to the upper sprocket wheel 1 via a transmission chain 6 and a chain wheel 7, 8 is a shaft of the upper sprocket wheel 1, and 9 is a trough 10 and dust. Is a guide plate for guiding the housing, 11 is a housing of the dust removing device, 12 is a flowing water channel, and F arrow is a direction of flowing water.

As shown in FIG. 4, the screen frame 4 is attached at every pitch of the link chain 3, and 14 is a screen main body, which is composed of a large number of rods arranged in the shape of a wire mesh or a plow, and is dust in running water. It is a member that prevents such things and scoops them up.

Reference numeral 15 is an upper beam provided at the upper end of the screen body 14, and the upper beam 15 is a pipe having a diameter suitable for the width of the water channel, and the center of which is the roller 3b of the link chain 3. The screen body 14 is integrally fixed via a mounting plate 16 provided so as to be located at the center of the screen and projecting from the lower part thereof.
Reference numeral 17 denotes a lower beam having a U-shaped cross section provided at the lower end of the screen body 14, and the lower beam 17 rotatably covers the upper portion of the upper beam 15 of the screen frame 4 adjacent to the lower portion thereof. The screen main body 14 is integrally fixed via a mounting plate 18 provided on the upper part of the screen.

Reference numeral 19 denotes a side plate for holding the screen body 14 from its side portion. The side plate 19 has a width wider than the link width of the link chain 3 as shown in FIG. It is fixed integrally to each end face. In other words, the side plate 19, the upper beam 15 and the lower beam 17 form a frame body (screen frame 4) for holding the screen body 14. The frame body is fixed to the link chain 3 by fixing the side plate 19 to the side surface of the link 3a with the bolt 20. Reference numeral 21 denotes a dust bucket projecting from the lower beam 17. The dust bucket 21 is provided so as to obliquely cover the lower front part of the screen main body 14, and the left and right ends of the dust bucket 21 are provided with side plates 19 via a support plate 22. Is integrally fixed to. Reference numeral 23 is a spray pipe provided at the back of the descending screen 13 for ejecting spray water to the back surface of the screen 13 as shown by a chain line so as to remove the dust attached to the screen body 14. Is. Therefore, dust or the like floating in the flow is first blocked by the screen body 14, and is scooped up by the dust bucket 21 as the link chain 3 rises, and the dust bucket 21 containing the dust further rises, and the upper sprocket 1 It becomes horizontal at the top of, then flips and descends.

Then, the dust existing in the dust bucket 21 falls due to its gravity and is guided by the outer surface of the dust bucket 21 of the lower screen and the guide plate 9 to form the water channel 10.
Is discharged inside. On the other hand, dust and the like adhering to the screen body 14 is separated by the spray water and discharged to the trough 10 via the outer surface of the dust bucket 21 of the lower screen and the guide plate 9 as described above.

The endless link chain 3 to which the screen frame 4 constructed as described above is joined is usually driven by the upper sprocket wheel 1 having about 6 teeth. In addition,
The L arrow indicates the link chain driving direction.

[0010]

In recent years, as the amount of water intake has increased, the width of the water channel has become wider, while the dust particles floating in the water channel tend to increase. Therefore, there is a demand for increasing the size of the dust removing device and improving the dust removing capability. Is getting stronger. Furthermore, there is a large gap between the processing capacity between the time when there is relatively little dust and the time when there is an abnormality due to the influx of a water mica that occurs in large quantities in seasons. ，
Since a low processing capacity is usually sufficient, the initial cost and running cost are high, which is uneconomical. On the contrary, if the design is adapted to the processing capacity during normal operation, the operation will be harsh at abnormal times, resulting in inconvenience such as damage to the equipment such as burnout of the motor and disconnection of the link chain due to overload. Therefore, in the latter case, when the load torque of the power plant exceeds, for example, 110% of the rated torque, an emergency stop is applied to the power plant and the rated torque of 150% is exceeded.
When reaching 100%, a shear pin is interposed in the joint that transmits power, and this shear pin is cut off by shearing force,
To prevent damage to Link Chain and other devices 2
There were some safety measures in place. However, as shown in FIG. 6, the load torque is instantaneously exceeded the set torque (set to 110%) for some reason from the operating state A where the dust is small and the load torque is close to the rated torque. %) Even in the operating state B in which a stable continuous operation can be continued by returning to the vicinity, the emergency stop adopted as the first safety protection measure often acts on the power unit, stops the operation, and stops the operation frequently. Then, there was a problem that continuous operation was hindered.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and to make an emergency stop only in a dangerous state where a load torque exceeds a set torque for a certain period of time, the present invention provides an endless link. In a dust remover in which a screen frame provided with a screen for collecting dust is joined to the chain and the link chain is driven by a power unit via a pair of upper and lower sprocket wheels, the load torque of the power unit exceeds a set torque. A torque limiter for stopping the power plant at times is provided, and a stop command is issued to the power plant when an overload torque exceeding the set torque during operation continues in the operation circuit of the power plant for a preset time or more. The configuration is such that an emergency stop circuit for emitting is added.

[0012]

In the dust remover of the present invention, when the state in which the actual load torque exceeds the set torque (allowable torque) input to the torque limiter continues for a set time, an emergency stop command is issued to the power unit and the power circuit Is cut off and operation is stopped. Therefore, if the load torque exceeds the set torque momentarily, the operation is continued without any emergency stop.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 relate to an embodiment of the present invention,
FIG. 1 is a power circuit and operation circuit diagram of the power unit of the dust remover, and FIG. 2 is an operation circuit diagram. In FIG. 1, an electric motor M, which is a power device of the dust removing device, is an electromagnetic switch M incorporated in a power circuit X composed of three-phase AC power supplies R, S, and T.
It is driven by energizing C. On the other hand, the operation circuit Y is composed of an operation circuit Y ₁ for starting or stopping and an operation circuit Y ₂ for emergency stop. The operation circuit Y ₁ is started by the start push button switch B _ON of the operation circuit Y ₁ and is stopped by the stop push button switch B _OFF. Stops the electric motor M. Torque limit switch LS ₁ is motor timer TR
It is a circuit for start compensation that continues the operation regardless of the peak overload torque at the time of start, and shuts off the electromagnetic switch MC for the motor through the coil #MC only when the overload exceeds the set time of the motor timer TR. Then, the electric motor M is stopped. On the other hand, the operation circuit Y ₂ has the configuration shown in FIG. 2, and the torque limit switch LS ₂
Therefore, if the torque exceeds the preset torque for a preset time (set time t _S ) or longer, the relay CR is activated to de-energize the electromagnetic switch MC of the power circuit X to shut it off. The electromagnetic switch MC is energized by energizing the coil #MC of the electromagnetic switch MC.

By setting the time t _S of the timer T to be normally 5 to 10 seconds, for example, as in the operating state C of FIG. 6, the time over which the load torque exceeds the set torque is maintained over the set time t _S. Then, the relay CR operates to stop the electric motor M in an emergency. When the load torque exceeds the set torque for a moment less than 1 second, as in the operating state B of FIG. It can be prevented.

As described above, in the dust remover of the present invention, the power unit is provided with the torque limiter, and the electric motor is operated only when the load torque exceeds the set torque for a time preset by a timer or the like in the operating circuit of the power unit. Since a circuit for emergency stop is provided, it is possible to continue operation without stopping even for momentary overload torque. Therefore, driving operation is easy and unnecessary emergency stop is avoided.

[0016]

EFFECTS OF THE INVENTION In the dust remover of the present invention, the continuous operation is carried out except when there is a danger that the overload torque, which causes troubles in operation such as damage to the equipment or burnout of the motor, is continuously caused. As a result, the operability is improved and the driving operability is improved.

[Brief description of drawings]

FIG. 1 is a power circuit and operation circuit diagram of a power unit of a dust remover according to an embodiment of the present invention.

FIG. 2 is a main part operation circuit diagram of the power unit of the dust removing device according to the embodiment of the present invention.

FIG. 3 is an overall vertical sectional view of a conventional dust removing device.

FIG. 4 is a vertical cross-sectional view of a screen frame of a conventional dust removing device.

FIG. 5 is a front view of a screen frame of a conventional dust removing device.

FIG. 6 is a load torque fluctuation curve diagram received by the power unit of the dust remover during operation.

[Explanation of symbols]

1 Upper sprocket wheel 2 Lower sprocket wheel 3 Link chain 4 Screen frame 5 Power unit 6 Transmission chain 14 Screen body 15 Upper beam 17 Lower beam 19 Side plate 21 Dust bucket M Electric motor MC Electromagnetic switch for motor LS ₁ Torque limit switch (start compensation LS ₂ torque limit switch (for emergency stop) T timer CR relay X power circuit Y operation circuit Y ₁ operation circuit (for start / stop) Y ₂ operation circuit (for emergency stop) t _S set time

Claims (1)

[Claims] 1. A dust remover in which a screen frame provided with a screen for collecting dust is joined to an endless link chain, and the link chain is driven by a power unit via a pair of upper and lower sprocket wheels. Is equipped with a torque limiter for stopping the power unit when the load torque exceeds the set torque, and the operating circuit of the power unit is operating, the overload torque exceeding the set torque continues for a preset time or more. A dust remover provided with an emergency stop circuit that sometimes issues a stop command to the power unit.