JPH0557085B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for cleaning a concrete mixer.

(Prior art) The conventional method of cleaning a concrete mixer is to inject water into the mixer using the water injection pipe while the mixer is running after all mixing work is completed, and then the mixing blades are attached. After washing away the deposits and deposits on the kneading arm and the rotating shaft to which the kneading arm is attached, a worker enters the mixer and removes the deposits and deposits by spraying them with pressure water from the jet nozzle. If the problem could not be removed with a hammer, it was removed by jetting pressurized water while hitting it with a hammer. However, after all the mixing work has been completed, the cement has begun to harden and it becomes difficult to remove the deposits and deposits, so this work requires a lot of effort and time, and is extremely difficult work. The work was extremely physically dangerous due to incorrect operation.

In addition, with other concrete mixer cleaning methods,
A nozzle is installed on the ceiling inside the mixer, and this is connected to the kneading water circuit connected to the measuring tank and pump. During kneading of each batch, a part of the kneading water is pressurized and sprayed from the nozzle to the kneading arm. The company was attempting to reduce the amount of work required after the kneading process was completed by removing deposits and deposits from the rotating shaft. However, since a portion of the kneading water is used, there is a limit to the amount of water, and the rotating kneading arm and rotating shaft pass under the fixed washing pipe in a very short time, so a sufficient cleaning effect cannot be achieved. Therefore, it took a considerable amount of time to clean up after the kneading work was completed. in the end,
Both conventional cleaning methods require workers to enter the mixer wearing waterproof gear and perform manual work in small, cramped spaces with limited physical freedom, which is extremely difficult for workers. It was work, and it was dangerous work.

(Object of the Invention) Therefore, an object of the present invention is to provide a method for cleaning a concrete mixer that can easily remove deposits and deposits inside the concrete mixer.

(Structure of the Invention) In order to achieve the above object, according to the present invention, a dedicated cleaning water circuit is provided, separate from the mixing water circuit, for pressure-feeding the cleaning water to the concrete mixer by a cleaning water pump. is connected to the kneading water circuit downstream of the pump, and during cleaning work between kneading operations, a valve closes the flow path to the kneading water pump, and connects the flow path to the cleaning water pump and the kneading water circuit. The nozzle connected to the kneading water circuit and the cleaning water circuit are connected by starting the cleaning water pump while slowly rotating the rotating shaft in the kneading tank. Cleaning can be done by spraying a large amount of high-pressure water into the concrete mixer from a nozzle connected to the concrete mixer.

(Effects of the Invention) According to the above method, a large amount of high-pressure water is slowly released from a large number of nozzles between kneading operations, before the cement begins to harden, and at a stage when there are few deposits or attachments in the mixer. Since the high-pressure water is sprayed onto the rotating shaft, kneading arm, and kneading blades, the time required for the high-pressure water to continuously hit the mortar and cement deposited on these rotating bodies at specific locations increases the speed of the mixer during the kneading process. This is considerably longer than the time required for the rotational speed, so that the process of disintegrating and falling off the mortar and cement takes place continuously without interruption, so that the cleaning effect is significantly enhanced.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings with regard to an example.

FIGS. 1 and 2 show an embodiment of a pan-type forced stirring concrete mixer cleaning device for a batch plant according to the present invention. FIG. 3 particularly shows the inside of the mixer of the concrete mixer cleaning apparatus shown in FIGS. 1 and 2 in cross section.

As is well known, inside the mixing tank 2 of the concrete mixer installed on the mixer floor 1a of the Battiya plant, there is a mixing tank 2 for mixing sand, cement, gravel, mixing water, etc. as shown in Fig. 3. a kneading arm 4 that supports the blade 3 and the kneading blade;
5. Rotatable rotating shaft 6 to which the kneading arm is fixed
is provided. A material input port 7 is provided in the upper part of the kneading tank 2, and a material measuring tank 8 is further arranged above the material input port 7. A mixer gate 27 (FIG. 3) is provided at the bottom of the kneading tank 2, and a concrete hopper 9 is arranged below the mixer gate 27 for discharging concrete after mixing. Further, above the kneading tank 2, a kneading water pump 10 connected to a kneading water measuring tank 10a is provided, and a pipe 13 connected to this kneading water pump is connected to a pipe 13a and a pipe 13.
One pipe 13a is a kneading water nozzle 11 attached to the ceiling of the kneading tank 2 for cleaning the rotating shaft 6, kneading arms 4, 5, and kneading blades 3.
The other pipe 13b is connected to the pipe 12 which extends into the mixer via a rotary joint 25 on the mixer ceiling.
Nozzle 1 directed radially towards the mixer side wall from
2a to form a customary kneading water circuit. In this case, the piping of the nozzle 12a is fixed to the rotating shaft 6 and the kneading arm 5, and rotates together with them. A nozzle 12b directed from the pipe 12 toward the mixer ceiling is provided for cleaning the mixer ceiling. Note that a dust collector (fan) 14 is connected to the kneading tank 2 to absorb dust inside the kneading tank 2 during the kneading operation.

According to the present invention, a dedicated cleaning water circuit separate from the kneading water circuit is provided in order to forcefully send the cleaning water from the existing wastewater treatment device 15 into the kneading tank 2 using the high-pressure cleaning water pump 16. . In this cleaning water circuit, a pipe 18 from a high-pressure cleaning water pump 16 is connected to a pipe 18a via a shutoff valve 21, and this pipe 18a connects to a cleaning water injection nozzle 17a added to the ceiling of the kneading tank 2. 17b. The cleaning water jet nozzle 17a is directed toward the ceiling and side walls, and the water jet nozzle 17b is directed downward. On the one hand, the line 18 branches before the shut-off valve 21 by a line 19 which connects the line 13 of the mixing water circuit to the valve 2.
0, for example via a three-way valve, so that the kneading water circuit can be used for cleaning purposes.

A drainage hopper 22 is arranged below the gate 9a of the concrete hopper 9 below the mixer gate 27 to receive the cleaning water that has finished cleaning the inside of the mixing tank 2, and this drainage hopper is clear from FIG. As such, it is attached to the frame 1b via an arm 23 so as to be pivotable between a use position A below the concrete hopper 9 and a standby position B on an imaginary line to the side thereof. The waste water hopper 22 is further connected to a waste water treatment device or a recovered water tank 1.
5 by a return pipe 24. In FIG. 3, the return circuit from below the mixer gate 27 to the tank 15 is omitted.

Next, a method of operating the concrete mixer cleaning apparatus constructed as described above will be explained with reference to the time chart shown in FIG. 4.

When starting mixer cleaning between kneading operations, turn on the cleaning push button switch and display ``Mixer Cleaning'' to prevent danger. The dust collection fan 14 is stopped to prevent spraying and suction of cleaning water. The drainage hopper 22 is pivoted from the standby position B to the use position A below the concrete hopper 9. Turn on the high-pressure cleaning water pump 16, open the shutoff valve 21 at the same time, and open the three-way valve 20.
The pipe 19 side and the pipe 13b side are communicated with each other, and the pipe 13 side is cut off. Turn on the mixer, rotate the rotary shaft 6, kneading arms 4, 5, and kneading blades 3 (see Figure 3) for 2 seconds, then turn off the mixer and continue for 7 seconds. During this time, the kneading arms 4 and 5 and the kneading blade 3 rotate slowly. Therefore, since the kneading arms 4, 5 and the kneading blades 3 slowly pass under the nozzle 11, the cleaning effect of the cleaning water sprayed from the nozzle 11 is increased. At this time, of course, other nozzles 12a, 12b, 17a, 17
Cleaning water from b is injected to clean the inside of the mixer. The nozzles 12a and 12b, which rotate together with the rotating shaft 6 and the kneading arm 5, clean the side walls and ceiling inside the mixer. Furthermore, turn on the mixer (2
2 seconds) and OFF (7 seconds), and after 30 to 60 seconds, close the shutoff valve 21 and close the pipe 13 of the three-way valve 20.
The side and the 13b side are communicated with each other, and the pipe 19 side is cut off.
At the same time, the mixer gate 27 (Fig. 3) is opened, the used cleaning water is discharged to the concrete hopper 9, and the timer setting time (15 in Fig. 4) is set.
seconds), close the mixer gate 27 and turn off the mixer.
and stop driving. Close the shutoff valve 21, connect the three-way valve 20 to the pipe 13 side to shut off the pipe 19 side, and at the same time turn on the high-pressure cleaning water pump 16.
Turn it off. The timer setting time has elapsed since the mixer gate 27 was opened and water was drained (10 seconds in Figure 4).
After that, when the gate 9a of the concrete hopper 9 is opened, water exclusively for cleaning enters the drainage hopper 22 and is returned to the recovered water tank 15 from there. The drain hopper 22 rotates and returns to the standby position B, and the "mixer cleaning in progress" display disappears. Note that the cleaning work time according to this time chart is 65 seconds. In this way, the inside of the mixer is cleaned using the kneading water nozzle and the nozzle newly installed for cleaning.

An embodiment of the present invention in which cleaning work inside the mixer is incorporated into the daily concrete mixing work cycle will be described with reference to FIG. In this case, the cleaning device of FIG. 1 constitutes an automated mixer cleaning system in relation to the kneading time so that the cleaning operation is automatically performed between each kneading operation.
In the example shown in Figure 5, operations start at 8 a.m. and end at 5 p.m., the kneading time is 45 seconds, and the discharge time is 15 seconds.
It operates continuously with a cycle time of 60 seconds per batch. The inside of the mixer is cleaned using mixing water during concrete mixing for each batch, and also during the 1.5 hour mixing period using a mixing water nozzle and a nozzle connected to the cleaning water circuit. Work is done. In this embodiment, the cleaning interval is set to 1.5 hours, but the cleaning interval is preferably 1 to 2 hours, and it is desirable to perform the cleaning at least once every 2 hours. When using early-strengthening cement, it is better to set short cleaning intervals because it begins to harden quickly. In the embodiment shown in FIG. 5 using the cleaning method of the present invention, it is sufficient to perform six cleaning operations a day (total time approximately 6 minutes) with each cleaning operation time of 65 seconds; This method required cleaning during lunch breaks and entering the mixer at the end of the day's work to perform difficult and dangerous work over an hour.

The concrete mixer cleaning device of the present invention can be applied not only to pan-type forced stirring mixers and twin-shaft forced stirring mixers, but also to stacked mixers.

[Brief explanation of the drawing]

Fig. 1 is a side view of a concrete mixer for a batchya plant equipped with a cleaning device according to the present invention;
The figure is a schematic plan view of the batchia plant shown in Fig. 1, Fig. 3 is a sectional view showing the inside of the concrete mixer shown in Fig. 1, Fig. 4 is a time chart when operating the cleaning device of the present invention, and Fig. 5 is a schematic plan view of the batchia plant shown in Fig. 1. The figure is a time chart showing an example in which the cleaning method of the present invention is incorporated into the daily concrete mixing work cycle and carried out automatically. 2...Kneading tank, 4, 5...Kneading arm, 6...
Rotating shaft, 10... Kneading water pump, 13, 13
a, 13b...Kneading water circuit, 11, 12a, 12
b...Nozzle of the kneading water circuit, 13...Flow path to the kneading water pump, 13a, 13b...Flow path to the nozzle for the kneading water circuit, 16...Washing water pump,
17a, 17b... Nozzle of water circuit for cleaning only, 1
8, 18a...Cleaning water circuit, 18, 19...
Flow path to the cleaning water pump, 20...valve.

Claims (1)

[Claims] 1 Separately from the mixing water circuit, a dedicated cleaning water circuit is provided to forcefully send the cleaning water to the concrete mixer using a cleaning water pump, and this is connected to the mixing water circuit downstream of the pump, so that it can be used between mixing operations. During cleaning work, the flow path to the mixing water pump is closed using a valve, and the flow path to the cleaning water pump and the mixing water circuit nozzle are communicated with each other. While slowly rotating the rotating shaft, start the cleaning water pump and inject a large amount of high-pressure water into the concrete mixer from the nozzle connected to the mixing water circuit and the nozzle connected to the cleaning water circuit. A method for cleaning a concrete mixer, characterized in that the concrete mixer is cleaned by