JPH02265710A - Method of cleaning concrete mixer - Google Patents

Abstract

PURPOSE:To enable adhesives or accumulations to be simply removed by washing the inside of a mixer in jetting a great quantity of highly pressurized water thereinto from nozzles connected to a kneading water conduit, or nozzles connected to a washing water conduit of being different system from the kneading water conduit, or both nozzles of them. CONSTITUTION:A drain hopper 20 is turned from a waiting position B to a working position A under a concrete hopper 9. A washing high pressure pump 18 is turned on, at the same time, a three way valve 12 is operation, to make the side of a pipe 19 and the side of a pipe 13 communicate with each other, and the side of a pipe 11 is disconnected then. Highly pressurized washing water is jetted into the mixer from nozzles 15. As the mixer is turned 'ON', and rotating shafts 5, kneading arms 4, and kneading brades 3 are thus rotated, an inner wash for the mixer is carried out. In the particular, since the mixer has horizontal shafts and short kneading arms in comparison with a pan-typed mixer having vertical rotating shafts, and when nozzles are provided above the rotating shafts in parallel, it always receives washing water except when the kneading arms and the kneading blades come just below the rotating shafts, accordingly, a sufficient washing effect can be obtained in remaining the number of rotation of the rotating shafts in the kneading bath rotating constant.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for cleaning a concrete mixer.

[Conventional technology and problems to be solved] The conventional method of cleaning a concrete mixer is to inject water into the mixer using a water injection pipe for mixing water while the mixer is running after all mixing work is completed. After washing off the deposits and deposits on the kneading arm to which the kneading blades are attached and the rotating shaft to which the kneading arm is attached, a worker enters the mixer and sprays pressurized water from a jet nozzle onto the deposits and deposits. It was removed by spraying, or if pressure water could not be used to remove it, it was removed by hitting it with a hammer and spraying pressurized water. However, after all the kneading work is completed, the cement has begun to harden, making it difficult to remove the deposits and deposits, so this cleaning work requires a lot of effort and time, and is extremely difficult work. The work was extremely physically dangerous due to incorrect operation.

Another method of cleaning a concrete mixer involves installing a nozzle on the ceiling inside the mixer and connecting it to a mixing water circuit connected to a metering tank and a pump, which allows some of the mixing water to be removed during mixing of each batch. The idea was to use pressurized spray from a nozzle to remove deposits and deposits from the kneading arm and rotating shaft, thereby reducing the amount of cleaning work required after kneading work is completed. However, since only a portion of the kneading water is used, the amount of water is limited, so a sufficient cleaning effect cannot be achieved, and cleaning after the kneading operation takes a considerable amount of time. 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 very tiring for workers. It was work, and it was dangerous work.

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.

[Means to solve the problem]

In order to achieve the above object, in the concrete mixer cleaning method according to the present invention, a mixing water circuit and a separate cleaning water circuit are provided and these circuits are connected in order to forcefully send cleaning water to the concrete mixer using a pump. Then, while rotating the rotary shaft between mixing operations, a large amount of high-pressure water is supplied into the concrete mixer from the nozzle connected to the mixing water circuit, the nozzle connected to the washing water circuit, or both nozzles. Spray and clean.

(Effects of the invention) While rotating the rotating shaft during the mixing operation, the nozzle connected to the kneading water circuit, or the nozzle connected to the kneading water circuit and the cleaning water circuit of another system, or both nozzles. According to the method of cleaning the concrete mixer by injecting a large amount of high-pressure water into the concrete mixer, it is possible to clean the mixer between mixing operations, before the cement begins to harden, and at a stage when there is little deposit or adhesion inside the mixer. Since the work can be carried out by jetting a large amount of high-pressure water, deposits and deposits can be removed very easily and a remarkable cleaning effect can be achieved.Therefore,
It is possible to significantly reduce the amount of difficult and dangerous work that workers have to do by entering the mixer.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings.

1 and 2 show an embodiment of the two-wheel type forced stirring concrete mixer cleaning device for a batcher plant according to the present invention. In particular, FIG. 3 shows the inside of the mixer of the concrete mixer cleaning device of FIGS. It is shown in cross section.

As is well known, mixing blades are installed inside the mixing tank 2 of the concrete mixer installed on the mixer floor la of the batcher plant, as shown in Figure 3, in order to mix sand, cement, gravel, mixing water, etc. 3. A mixing arm 4 that supports the kneading blades, and two rotatable horizontal rotating shafts 5 to which the mixing arm is fixed are provided in parallel (Fig. 4) at the top of the kneading tank 2. There are three material input ports 6 for sand, cement and gravel, and above these there is also a material metering tank 7 (FIG. 1).

Mixer gate 8 (Figures 1 and 3) is installed at the bottom of the kneading tank 2.
is provided, and a concrete hopper 9 is arranged below it for discharging concrete after crosstalk. Further, above the kneading tank 2, a wash water pump 10 connected to a kneading water measuring tank 10a is provided, and a pipe 11 connected to this wash water pump is connected to a pipe 13 via a three-way valve 12. 13 branches into pipes 14 and 14' (Fig. 4), and the pipes 14 and 14' are pipes arranged at the upper part of the kneading tank 2 for cleaning the rotating shaft 5, mixing arm 4, and mixing vane 3, respectively. A large number of kneading water nozzles attached to 15.
15' to form a customary kneading water circuit.

Incidentally, a dust collector (fan) 16 is connected to the kneading tank 2 in order to absorb dust inside the kneading tank 2 during the kneading operation.

According to the present invention, a wash water circuit separate from the kneading water circuit is provided to force wash water from the existing wastewater treatment device 17 into the kneading tank 2 using the high-pressure pump 18. A pipe 19 from a high-pressure pump 18 forming this wash water circuit is connected to the kneading water circuit by a three-way valve 12. Therefore, downstream of the three-way valve 12, a kneading water circuit is used.

Below the gate 9a of the concrete hopper 9 located below the mixer gate 8, there is disposed a drainage hopper 20 for receiving the washing water that has been washed inside the mixing tank 2, and this drainage hopper is clearly visible in FIG. It is attached to the frame lb via an arm 21 so as to be able to pivot between a use position A below the concrete hopper 9 and a standby position B on an imaginary line on the side thereof. The wastewater hopper 20 is further connected to a return pipe 2 to a wastewater treatment device or a recovered water tank 17.
2, thereby forming a closed circuit for the wash water. In FIG. 3, the return circuit from below the mixer gate 8 to the tank 15 is omitted.

Note that 23 indicates a cement measuring tank.

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.

When starting to clean the mixer between kneading operations, turn on the cleaning push button switch to display "Mixer cleaning in progress" to prevent danger. The dust collection fan 16 is stopped to prevent spraying and suction of cleaning water. The drainage hopper 20 is pivoted from the standby position B to the use position A below the concrete hopper 9. The cleaning high-pressure pump 18 is turned on, and the three-way valve 12 is operated at the same time to communicate the pipe 19 side and the pipe 13 side, and shut off the pipe 11 side. High-pressure cleaning water is sprayed into the mixer from the nozzle 15. Turn on the mixer and rotate the rotating shaft 5, kneading arm 4, and kneading blade 3 (see FIGS. 3 and 4).

During this rotation, the inside of the mixer is cleaned. In particular, in the case of two-wheel or single-shaft mixers, the rotating shaft is horizontal and the crosstalk arm is short compared to a pan-type mixer with a vertical rotating shaft.
By installing a nozzle parallel to the top of the rotating shaft, the kneading arm and mixer blade will always receive cleaning water except when they are directly below the rotating shaft, allowing the rotating shaft in the kneading tank to rotate at a constant rate without reducing its rotational speed. A sufficient cleaning effect can be obtained even while rotating. After about 30 to 60 seconds of the timer setting time have elapsed, the pipe 11 side and the pipe 13 side of the three-way valve 12 are brought into communication, and the pipe 19 side is cut off. At the same time, the mixer gate 8 (Fig. 1) is opened to discharge the used washing water to the concrete hopper 9.
After the timer setting time (10 seconds in FIG. 5), the mixer gate 8 is closed, the mixer is turned off, and the operation is stopped. As described above, the three-way valve 12 is connected to the pipe 11m to shut off the pipe 19 side, and at the same time, the cleaning high-pressure pump 18 is turned off.

After the timer setting time has elapsed (20 seconds in Fig. 5) after opening the mixer gate 8 and discharging water, the concrete hopper 9
When the gate 9a is opened, the wash water enters the drainage hopper 20, from where it is returned to the recovered water tank 17.

The drainage hopper 20 rotates and returns to the standby position B, and the "mixer cleaning in progress" display disappears. Note that the cleaning time according to this time chart is 65 seconds.

In this way, the inside of the mixer is cleaned using the kneading water nozzle.

In this example, a cleaning water circuit was connected to the mixing water circuit, and cleaning was performed by spraying cleaning water into the mixer from the mixing water nozzle 15 of the mixing water circuit. In addition, a wash water nozzle 25 is provided in the kneading tank 2 in addition to the kneading water nozzle 15, and this is connected to the pipe 19 from the high-pressure pump 18 via a pipe 26 and a shutoff valve 27 to create a separate wash water circuit. can be formed. When this separate wash water circuit and wash water nozzle are provided, by closing the three-way valve 12 and opening the cutoff valve 27, this wash water circuit can be used solely to spray wash water into the mixer from only the wash water nozzle 25. Alternatively, both the three-way valve 12 and the cutoff valve 27 can be opened to spray the cleaning water from both the cleaning water nozzle 25 and the kneading water nozzle 15.

An embodiment in which the method for cleaning the inside of a mixer according to the present invention is incorporated into a 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 conjunction with the kneading time so that cleaning occurs automatically between each kneading operation. In the example shown in FIG. 6, the operation starts at 8:00 a.m. and ends at 5:00 p.m. The kneading time is 45 seconds and the discharge time is 15 seconds, that is, the cycle time is 60 seconds per batch. The inside of the mixer is cleaned using mixing water during concrete mixing for each batch, and also using a mixing water nozzle between 1.5 hours of mixing work time. In addition, in this example,
The cleaning interval was set to 1.51, but this cleaning interval was
Two hours is preferred, and it is desirable to wash at least once every two hours. When using early strength cement,
Since caking starts early, it is better to set the cleaning interval short. In the example shown in FIG. However, with conventional cleaning methods, it takes more than an hour to clean the mixer during the lunch break, and then to go into the mixer after work on the day - and perform difficult and dangerous cleaning work. It had to be done.

Although the concrete mixer cleaning device of the present invention is applicable to all mixers, it is particularly effective for single-layer type one-shaft or two-wheel forced stirring mixers and laminated type one-shaft or two-wheel forced stirring mixers.

[Brief explanation of drawings]

FIG. 1 is a side view of a concrete mixer for a batcher plant equipped with a cleaning device according to the present invention, FIG. 2 is a schematic plan view of the batcher plant shown in FIG. 1, and FIG. 4 is a cross-sectional view showing the inside; FIG. 4 is a plan view of the kneading tank shown in FIG. 3 taken along the line of arrow IV-IV; FIG. 5 is a time chart for operating the cleaning device of the present invention; 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 performed automatically. 2...Kneading tank 4...Mixing arm 5...Rotating shaft 10.11.13.14.14'...Kneading water circuit 15.15'...Kneading water circuit nozzle 19.26
...Cleansing water circuit 25...Cleansing water circuit nozzle Figure 4

Claims (1)

[Claims] (1) In order to forcefully send washing water to the concrete mixer using a pump, a mixing water circuit and a separate washing water circuit are provided and these circuits are connected, and the rotating shaft in the mixing tank is rotated between mixing operations. Cleaning of a concrete mixer, characterized in that a large amount of high-pressure water is injected into the concrete mixer from a nozzle connected to the mixing water circuit, a nozzle connected to the washing water circuit, or both of these nozzles. Method.