Ready mixed concrete quality keeping and fixing prevention method in agitator, and its device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a method for maintaining the quality of raw concrete in a stirrer affected by the outside air temperature and preventing sticking, and an apparatus for carrying out the method.

【0002】

[Conventional circumstances and technology]

When transporting raw concrete by agitator car, in the summer, the temperature inside the stirrer rises to about 30 to 40 ° C or more under the scorching sun, and the temperature shortens the curing time of the raw concrete. However, the strength is reduced. And this imposes restrictions on transportation time and distance (the time from the start of raw concrete production to unloading is determined to be within 90 minutes (JIS standard), and if it exceeds 90 minutes, the quality will deteriorate due to high temperature. Since it happens, it is usually rejected by the delivery destination as non-standard). Furthermore, the temperature inside the stirrer after discharging the raw concrete rises rapidly, and the residual raw concrete rapidly solidifies in a short time. In addition, due to the high temperature of the stirrer itself, the raw concrete may accumulate in the recesses inside the stirrer even before the ready-mixed concrete is discharged, and the concrete may solidify and stick without sufficient stirring. .. Therefore, even if water is ejected in a hurry immediately after the raw concrete is discharged, the residual raw concrete once solidified cannot be completely washed away.

【0003】

The solidified residual concrete that does not easily come off in this way is removed by a worker entering the stirrer and using a hammer or the like. On the other hand, in the case of a stationary batcher, water washing is usually performed immediately after the raw concrete is discharged, but the amount of adhesion gradually increases no matter how the water washing is performed, and it is diligent (at least one week). (Once in a while) had to do the fishing work. And in this way, whether it is an agitator car or a batcher, the fishing work performed inside the stirrer is very dangerous, and the switch is mistaken without knowing that the worker is still inside the stirrer. There is a tragic fatal accident every year due to turning on and rotating the stirrer. As a countermeasure, a safety device using a sensor for confirming the existence of a person as a stirrer has been proposed. However, complete safety measures were not possible because the cleaning work itself, which was carried out by workers, was not eliminated.

【0004】

On the other hand, in the cold season, the temperature inside the stirrer is adversely affected by the influence of the outside air temperature, which causes a decrease in the strength and quality of the ready-mixed concrete. To prevent this, measures have been taken to increase the cement content according to the outside air temperature. However, the work for the adjustment is extremely troublesome, and the material cost is wasted accordingly. It should be noted that the adhesion and solidification of residual raw concrete in the stirrer occurs in the same manner even if the temperature is not lower.

【0005】

Cooling that temporarily cools the raw concrete itself by using liquefied gas for the purpose of strengthening the strength of the concrete after casting, preventing cracks, and maintaining the quality of the raw concrete. Several devices have been proposed. Most of them are cooling devices that directly cool the ready-mixed concrete before transportation, and some cooling devices that cool the ready-mixed concrete at the casting site have also been proposed. In addition, a device (Japanese Patent Laid-Open No. 61-229507) has been proposed in which this is installed in an agitator vehicle (concrete mixer vehicle) and liquefied gas is injected into the raw concrete. However, although liquefied gas is extremely expensive and suitable for temporary cooling, it is not suitable because a large amount of liquefied gas is required to continue cooling during transportation.

【0006】

Furthermore, in order to cool the raw concrete, it has been proposed to mix and use crushed ice in the raw concrete, but if ice remains at the time of casting, that part becomes a void and the concrete There is a drawback that the strength is reduced.

【0007】

[Problems to be Solved by the Invention]

The present invention has been made in view of the above-mentioned actual conditions, and in any case of an agitator car or a batcher, cold air or hot air is sent into a stirrer affected by the outside air temperature. The temperature of the raw concrete is maintained in the set temperature range, the curing time is delayed while maintaining the quality of the raw concrete, and after the raw concrete is discharged, cold air is blown into the stirrer to maintain the residual raw concrete. It is intended to provide a method for removing the adhesiveness of concrete and a device for carrying out the method.

【0008】

[Means for solving problems]

In order to solve the above problems, the present invention continuously sends cold air to the raw concrete in the ready-mixed concrete stirrer 3 when the outside temperature is high in summer or the like, and the temperature is low in winter or autumn. When, dehumidified warm air is continuously sent to maintain the raw concrete temperature in the control set temperature range, delay the curing time while maintaining the quality of the raw concrete, and discharge the raw concrete. The rest is a method for maintaining the quality of the raw concrete in the stirrer and preventing sticking, which is characterized by blowing cold air into the stirrer 3 to remove the adhesiveness of the residual raw concrete.

【0009】

Then, the base end portion 2a of the blower duct 2 in which the tip portion 2b faces the upper space in the stirrer 3 of the raw concrete is connected to the cool / warm air blower 1, and the cool / warm air blower 1 is connected to the cool / warm air blower 1. A dehumidifier that has an air intake port 6 at one end and is equipped with a compressor-7 and a heater 9 that are operated by the control panel 12 between the air intake port 6 and the base end portion 2a of the air duct 2. 8. An air conditioner 10 equipped with a heat exchanger 11 is a device for maintaining the quality of raw concrete and preventing sticking in a stirrer for maintaining the quality of raw concrete and preventing sticking.

【0010】

Further, in the configuration of the above device, the stirrer 3 is provided in the agitator car 4 to maintain the quality of the raw concrete in the stirrer and prevent sticking.

【0011】

Further, in the configuration of each of the above devices, it is a device for maintaining the quality of raw concrete in the stirrer and preventing sticking, which is formed by coating all or a part of the outside of the stirrer 3 with a removable heat insulating material 5.

【0012】

BEST MODE FOR CARRYING OUT THE INVENTION [Embodiments of the Invention]

Embodiments of the present invention will be specifically described with reference to the drawings. The method for maintaining the quality of the raw concrete in the stirrer and preventing sticking according to the present invention is as described in claim 1, when the raw concrete in the raw concrete stirrer 3 has a high outside temperature. Cold air is continuously sent in, and when the temperature is low, dehumidified hot air is continuously sent in to maintain the raw concrete temperature in the set temperature range and to maintain the quality of the raw concrete while extending the curing time. The gist is to delay and blow cold air into the stirrer 3 after discharging the raw concrete to remove the adhesiveness of the residual raw concrete. by.

【0013】

That is, as shown in FIGS. 1, 2, 3, and 4, the base end 2a of the air duct 2 with the tip 2b facing the upper space in the raw concrete stirrer 3 is a cooling / warm air blowing device. It is connected to 1. FIGS. 1 to 3 show an embodiment using an agitator vehicle 4, and FIG. 4 shows an embodiment using a batcher. FIG. 5 shows a mode in which the outside of the stirrer 3 is covered with the heat insulating material 5, and FIG. 6 shows a mode in which the outside of the air duct is covered with the heat insulating material 5.

【0014】

As shown in FIGS. 7 and 8, the cooling / warming air feeding device 1 has an air intake port 6 at one end, and is located between the air intake port 6 and the base end portion 2a of the air blowing duct 2. It is equipped with a compressor-7 operated by the control panel 12, a dehumidifier rotating with a moisture absorber 9 equipped with a heater 9, and an air conditioner 10 equipped with a heat exchanger 11, after sucking and compressing the taken-in outside air. In order to maintain the ratio of cement and water in the stirrer 3, dehumidify 50% or more by the moisture absorber 8 and guide it into the air conditioner 10 equipped with the heat exchanger 11. In the figure, 8a is an air discharge pipe containing moisture, 8b is a rotating moisture absorbing plate, 8c is a driving motor of the rotating moisture absorbing plate 8b, and 8d is an intake pipe of a heater 9.

【0015】

The dehumidified air guided into the air conditioner 10 becomes cold air or warm air that is controlled and set in advance by the control panel 12 via the heat exchanger 11, passes through the air duct 2, and enters the stirrer 3 from the base end portion 2a. Is sent to. In the figure, 10a is a duct fan and 10b is a damper.

【0016】

That is, in the summer, in the case of transportation under the scorching sun by the agitator car 4, cold air is continuously sent from immediately before or immediately after the loading of the raw concrete until immediately before the cleaning inside the stirrer 3, and the raw concrete in the stirrer 3 is continuously sent. Maintain the temperature in the set temperature range of about 1 ° C to about 15 ° C to maintain the quality of the raw concrete, delay the curing time, and after the completion of the discharge of the raw concrete at the site (raw concrete). -Water shall be injected into the stirrer 3 (before the concrete is cured) to wash away the residual concrete. If the start time of the cleaning work in the stirrer is delayed, the cold air is not stopped and is continuously sent until just before the cleaning. Note that once the raw concrete solidifies, it becomes more and more adherent to the inner wall of the stirrer.

【0017】

Whether or not the inside of the stirrer 3 maintains the set temperature range of about 1 ° C to about 15 ° C shall be detected by the temperature sensor- (omitted in the figure) facing the inside of the stirrer 3. -And the control panel 12 are electrically connected via bimetal. Specifically, it will be achieved by attaching a temperature sensor to the tip 2b of the air duct 2.

【0018】

That is, when the temperature sensor detects that the raw concrete temperature in the stirrer 3 has exceeded the set temperature, the air conditioner 10 is controlled to restart, and the temperature is lowered to the set temperature to always live in the stirrer 3. Make it possible to maintain the concrete temperature in the set temperature range (about 1 ° C to about 15 ° C). For example, when the outside air temperature reaches 28 ° C, the temperature inside the stirrer 3 rises and the raw concrete temperature rises above about 15 ° C, restart the air conditioner 10 and lower it by about 3 ° C to about 12 ° C. Keep it below ° C.

【0019】

In winter or autumn, if the raw concrete temperature inside the agitator car or batcher stirrer 3 drops below the set temperature due to the outside air temperature, on the contrary, dehumidified warm air is continuously blown into the stirrer 3. To maintain the temperature within the set temperature range of the raw concrete, to maintain the quality and delay the curing time, and after the completion of the discharge of the raw concrete, only cold air is sent to inject water into the stirrer 3 and remain. The raw concrete shall be washed away. The point that the air conditioner 10 is restarted by detecting the raw concrete temperature in the stirrer 3 by the temperature sensor is the same as before.

【0020】

The temperature of the air conditioner 10 is fixedly set according to the season (for example, -10 ° C during the period from June to September, and from November to February the following year, without using temperature control by a temperature sensor, etc. The period can be set to +5 ° C), and the set value may be adjusted in small steps. Further, in the embodiment of FIG. 8 carried out on the batcher stirrer 3, the temperature of the water (normally normal temperature water) to be put into the stirrer 3 together with the cement for stirring is adjusted (for example, 1 ° C to 5 in spring and summer). It is also possible to adjust the temperature of the in-flight concrete in synergy with the above-mentioned cold air and warm air adjustments by adjusting the temperature to 30 ° C to 70 ° C in autumn and winter.

【0021】

When cooling the entire inner wall of the stirrer 3, cold air flows downward, so it is necessary to open the air duct 2 so as to face the upper space inside the stirrer 3. In the embodiment of the agitator car (Japanese Patent Laid-Open No. 61-229507) that is press-fitted into the inside of the conventional raw concrete, air bubbles are mixed in the raw concrete and the concrete strength is lowered. Become.

【0022】

In the agitator car 4 equipped with the stirrer 3 in the car, the air conditioner 10 can be operated by using the car engine as a power source, so that the agitator car 4 can be continuously operated for a long time at low cost.

【0023】

In summer, the temperature inside the stirrer 3 may rise to 40 ° C or higher when exposed to direct sunlight. However, as shown in Fig. 2, Fig. 5, and Fig. 6, if the stirrer 3 part and the air duct 2 part are covered with the heat insulating material 5, the temperature rise can be prevented by that amount due to the heat insulating action, and the air-conditioning air conditioner 1 motor. The load on the tar and energy consumption can be reduced. Even in winter, the heat insulating action of the heat insulating material 5 works in the same manner, and the temperature drop can be prevented by that amount, and the load on the motor of the air conditioner 10 and the energy consumption can be reduced. It is desirable that the heat insulating material 5 be removable from the stirrer 3 and the air duct 2 at any time in order to effectively use the outside air temperature.

【0024】

In FIGS. 1 and 2, 13 is a water tank for storing water used for cleaning the inside of the stirrer 3, and 14 is a discharge sheet for ready-mixed concrete.

【0025】

[Effect of the invention]

The present invention is as described above. In either case of an agitator car or a batcher, cold air or hot air is sent into the raw concrete stirrer, which is affected by the outside temperature depending on the season and region, to make the raw concrete. -Maintain the temperature in the set temperature range, delay the curing time while maintaining the quality of the raw concrete, and after discharging the raw concrete, send only cold air into the stirrer 3 to make the residual raw concrete. It provides a method of removing the adhesiveness of raw concrete, and realizes maintenance of quality of raw concrete and a significant delay in curing time, especially in long-distance delivery.

【0026】

As a result, in the case of long-distance delivery with few relay bases, such as in areas without raw concrete bases, especially in the vast area of the United States, raw concrete raw materials, that is, raw sand, cement and water, are delivered separately. It is possible to transport raw concrete and clean the stirrer without using the laborious and costly method of manufacturing raw concrete locally (dry delivery), and it is possible to transport raw concrete at high temperature or at low temperature. You can place raw concrete underneath. Even reducing the number of relay bases will save a lot of money. In addition, the ease of washing the residual concrete with water eliminates the problem of work-related accidents that could be life-threatening.

【0027】

The cooling / warming air feeding device 1 for carrying out the above method has a simple structure, can be compactly designed, has low manufacturing cost and running cost, and can be easily installed in an agitator vehicle.

[Simple explanation of drawings]

[Figure 1]

Side view of the agitator vehicle according to the present invention [Figure 2]

Same as above side view with a stirrer coated with heat insulating material [Fig. 3]

Rear perspective view of an agitator vehicle according to the present invention [Fig. 4]

Schematic side view of the batcher in which the present invention is carried out. [Fig. 5]

Fig. 2 A-A vertical stirrup end view [Fig. 6]

Figure 2 Longitudinal section view of line B-B [Fig. 7]

Longitudinal side view of the device of the present invention carried out on an agitator vehicle [Fig. 8]

Longitudinal side view of the apparatus of the present invention carried out on the batcher. [Explanation of symbols]

1 Cool / warm air blower 2 Blower duct 2a Base end of air duct 2b Tip of air duct 3 Raw concrete stirrer 4 Agitator-Car 5 Insulation 6 Air intake 7 Compressor- 8 Moisturizer 9 Heater Moisturizer 10 air conditioner) 11 heat exchanger 12 Control panel 13 Water tank 14 Emission shot