JPH0436413Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a maintenance device for interface meters and turbidity meters (hereinafter referred to as "interface meters, etc."), and is used in wastewater treatment facilities equipped with rotating scrapers. Used for concentration sedimentation tanks, sedimentation ponds, etc.

[Conventional technology]

A scraper that rotates at a slow speed is installed near the bottom of the concentration sedimentation tank mentioned above, and gently stirs the treated water containing sludge poured in from the treated water inflow pipe, separates water and sludge, and removes the sludge. This promotes sedimentation.

To detect the sludge interface in such a concentration sedimentation tank, the interface meter is suspended in the tank using a waterproof wire that can be energized and is fed out or rewound by a winder. Normally, the winder is rotated in the normal direction to lower the interface meter to detect the sludge interface, and then the winder is reversed to rewind the wire and raise it. The same applies to turbidity meters that detect the turbidity of sludge and treated water.

[Problems that this invention attempts to solve]

However, since the sludge interface is located below the scraper after the accumulated sludge is discharged, the sludge interface cannot be accurately detected unless the interface meter is lowered below the scraper. In this case, if the interface meter is lowered between the blades of the rotating scraper, the rotation status cannot be seen from the outside, so there is a risk of damage to the interface meter due to collision or contact with the rotating blades. It was hot.

This risk of damage similarly occurs when the interface meter or the like is raised or lowered directly above the rotating blades of the scraper or near the rotating outer periphery of the blades.

[Means for solving problems]

This proposal is an attempt to solve the above problem, and is provided with a transmitter on the drive shaft of the scraper that transmits a detection signal for each blade including the front part in the rotating direction in synchronization with the rotation of the drive shaft, and the controller is set to send a reversal signal to the winder when this blade detection signal is input, and to send a forward rotation signal when the blade detection signal is not input, and the winder rewinds and rotates according to the reversal signal to raise the interface meter etc. The gist is that the interface meter and the like are lowered below the scraper by being rotated in response to a normal rotation signal.

[Effect]

When the transmitter does not detect the rotating blade including the immediately preceding part in the direction of rotation, no blade detection signal is generated, so the control unit sends a forward rotation signal to the winder, which causes the winder to rotate forward and unwind the wire. ,
The interface meter or the like descends below the scraper from between the rotating blades of the scraper or near the rotating outer periphery of the blades, and can detect the sludge interface or turbidity below.

During this downward detection, when the transmitter detects the rotating blade including the immediately preceding part in the rotation direction, a blade detection signal is sent to the control unit, and the control unit sends a reversal signal to the winder, so the winder When the wire is reversed and rewinded, the interface meter, etc. rises before it comes into contact with the blade, and the blade passes underneath it without any problem, completely preventing the interface meter, etc. from colliding with or coming into contact with the blade. be done.

〔Example〕

Figure 1 is a general configuration diagram of an example in which the device of the present invention is implemented in a concentration sedimentation tank, where 1 is a cylindrical concentration sedimentation tank, 2 is a treated water feed pipe, 3 is a treated water inlet pipe, and 4 is a scraper. , 5 is a drive shaft thereof, 6 is a drive motor attached to a support frame (not shown) above the sedimentation tank, and 7 is a sludge discharge pipe. This scraper 4 rotates at a very slow speed of about 30 to 40 minutes per revolution.

Further, in the concentration sedimentation tank 1, an interface meter 11 is suspended by a waterproof wire 10 that can be electrically connected and extends from the winder 8 through the depth sensor 9. The winder 8 rotates forward in response to a signal sent from the control section of the computer C and winds the wire 1.
0 is fed out or reversed to rewind the wire 10, and the interface meter 11 is lowered and raised to a set depth.The depth of this interface meter 11 is detected by the depth sensor 9, and the detected value is the same as described above. The information is input to the control section and displayed on the display section 12. Note that since these are conventionally known configurations, detailed explanations will be omitted.

In the device of the present invention, in such a sludge interface (or turbidity) detection means, a detection signal is sent to the drive shaft 5 for each blade including the immediately preceding part in the rotating direction in synchronization with the rotation of the scraper 4. A transmitter 13 is provided to control the raising or lowering of the interface meter 11 using this signal.

FIG. 2 shows a specific example of the configuration of this transmitting section 13. That is, corresponding to the positions of the blades 4a, 4b, 4c, and 4d of the scraper 4 fixed to the drive shaft 5, a cam ring 14 that protrudes outward slightly on the front side in the direction of rotation and is recessed on the rear side is attached to the drive shaft 5.
A limit switch 15 is provided opposite the cam ring 14 and operates when the protrusion comes into contact with the cam ring 14. This limit switch 15 is fixedly attached to, for example, the frame of the drive motor or the like.

The limit switch 15 sends a blade detection signal to the control section of the computer C when its contact contacts the protruding part of the cam ring 14, and when it faces the concave part of the cam ring 14 and does not come into contact with it, the limit switch 15 sends a blade detection signal to the control part of the computer C. It is designed not to generate a detection signal. Further, the control section is set to send an inversion signal to the winder 8 when the blade detection signal is input, and to send a normal rotation signal when the blade detection signal is not input.

Therefore, when the contact of the limit switch 15 faces the recessed portion of the cam wheel 14 and does not come into contact with it, no blade detection signal is generated, and a normal rotation signal is sent from the control section to the winder 8. As a result, the winder 8 rotates in the normal direction and feeds out the wire 10, so that the interface meter detects the scraper from between the rotating blades of the scraper 4 (area m shown in Fig. 2) or from near the rotating outer periphery of the blade. 4 and detects the lower sludge interface.

During this downward detection, when the blades of the scraper 4 approach, the contacts of the limit switch 15 come into contact with the protruding surface showing the front part of the blades of the cam wheel 14, and a blade detection signal is sent to the control section. , while this is in contact (region n shown in Figure 2),
A reversal signal is sent from the control section to the winder 8, the winder 8 is reversed and the wire 10 is rewound, and the interface meter 11 rises before it comes into contact with the blade, and the blade does not collide or contact. Pass below it without any trouble. This operation is
Thereafter, the process is repeated in the same manner.

In the above embodiment, the transmitter 13 is connected to the cam wheel 14.
and a limit switch 15; however, any other appropriate means may be used as long as it generates a detection signal including the immediately preceding portion of each blade in the rotating direction in synchronization with the rotation of the scraper 4. . Specifically, a detection metal piece may be attached to the protruding portion of the cam ring 14 described above, and this may be detected by a metal sensor to generate the signal. Further, in addition to the above-mentioned interface meter, the present invention can be similarly applied to a turbidity meter.

〔effect〕

As described above, the device of the present invention is provided with a transmitter on the drive shaft of the scraper that transmits a detection signal for each blade including the immediately preceding part in the rotating direction in synchronization with the rotation of the scraper.
The winder is rotated forward or backward in response to this blade detection signal via the control unit, and the interface meter, etc. is lowered and raised, so while each blade is rotating, the interface meter, etc. is lowered below the scraper. It is possible to reliably detect the sludge interface and turbidity in the lower part.
In addition, since the descended interface meter rises before coming into contact with each blade of the scraper, damage caused by collision or contact with the blades is completely prevented.

[Brief explanation of the drawing]

FIG. 1 is a general configuration diagram of an example in which the apparatus of the present invention is implemented in a concentration sedimentation tank, and FIG. 2 is an explanatory diagram of the operation shown along the line A--A in FIG. 1. 1... concentration sedimentation tank, 4... scraper, 4a,
4b, 4c, 4d...Blade, 5...Drive shaft, 8...
... Winder, 9 ... Depth sensor, 10 ... Wire, 11 ... Interface meter, etc., 13 ... Transmission section, 1
4...Cam wheel, 15...Limit switch.

Claims (1)

[Claims for Utility Model Registration] An interface meter, etc. is suspended in a concentration sedimentation tank or sedimentation tank equipped with a scraper with a wire that can be energized, and a winder is operated by an output signal from a control section to operate the interface meter, etc. In an apparatus for detecting a sludge interface or turbidity by raising and lowering the scraper, the drive shaft of the scraper is provided with a transmitter that transmits a detection signal for each blade including the immediately preceding part in the rotating direction in synchronization with the rotation of the scraper, and the control unit sends an inverted signal to the winder when this blade detection signal is input,
The winder is set to send a forward rotation signal when the blade detection signal is not input, and the winder rewinds and rotates according to the reversal signal to raise the interface meter, etc., and the winder unwinds and rotates according to the forward rotation signal to raise the interface meter, etc. above the scraper. A maintenance device such as an interface meter, which is characterized by being moved downward.