JPS6220257Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotating drum provided in a concrete mixer truck.

As is well known, concrete mixers are used to transport fresh concrete mixed at a concrete plant to the pouring site while stirring it with a rotating drum to prevent it from separating and to maintain proper quality. , fine aggregate, coarse aggregate, etc. are each weighed at the plant and put into a rotating drum, and after forming ready-mixed concrete in the rotating drum, it is stirred and run, and then transported and discharged as is. As shown in FIG. 1, the rotating drum has a conical drum body 2, which has a conical shape that narrows as it approaches the mouth part 1. The rotary drum has a mouth part 1 extending from the bottom part 3 of the drum body 2 to the inner surface thereof. It has a structure in which two spiral blades 4 are provided over the blade.

In such a concrete mixer truck,
As mentioned above, when making ready-mixed concrete from water, cement, etc. (this is called wet mixing), after putting water, cement, etc. into a rotating drum, the rotating drum is rotated at high speed to knead them. Although this is a good idea, conventional rotating drums had the disadvantage that the kneading efficiency was poor and the kneading time took about 15 minutes.

In addition to the conventional two spiral blades, the present invention provides a kneading blade with flow holes from approximately the center to the bottom of the drum body.
It is an object of the present invention to provide a rotating drum for a concrete mixer truck which eliminates the above-mentioned conventional disadvantages and can greatly improve the mixing efficiency using the kneading blades.

Hereinafter, the present invention will be explained in detail based on the drawings. 2 to 4 show an embodiment of the present invention, in which reference numeral 12 indicates a drum body of a rotating drum. As is well known, this drum body 12 is mounted diagonally on the loading platform of a traveling vehicle (not shown) with the mouth 11 facing up and the bottom 13 facing down. ), it can be rotated in any forward or reverse direction around the imaginary axis A, and is formed into a conical shape that narrows as it approaches the mouth 11. On the inner surface of the drum body 12, two blades 14, 14 are spirally provided so as to face each other from the bottom 13 to the mouth 11 of the drum body 12. These two blades 14, 14 have substantially the same shape as the conventional blades 4, 4, but differ in their details. FIG. 3 shows this difference. The blades 14, 14 have raised members 14a, 14 extending from the approximate center of the drum body 12 to the bottom 13, unlike the conventional blades 4, 4 shown by the two-dot chain line.
a is formed in a joined shape, and an extension member 14b is also provided at the tip of one blade 14 on the bottom 13 side.
It has become an added form.

Furthermore, the inner surface of the drum body 12 extending from approximately the center to the bottom 13 is filled with cement, aggregate, etc., which have been put into the drum body 12, by the blades 14,
two kneading blades 15 for kneading together with 14;
15 spirally so as to be substantially parallel to the blades 14, 14 and exactly in the middle position thereof,
They are arranged via connecting members 16, respectively. As shown in FIG. 4, the kneading blades 15, 15 are made by sequentially joining a plurality of blade members 15a, each having a different shape and a notch of a predetermined size, into a shape substantially the same as the blades 14, 14. The tip 15b on the bottom 13 side is formed at the same position as the tips of the blades 14, 14 in the direction of the mouth 11 and the bottom 13. Therefore, as a matter of course, the extension member 14b of the blade 14 protrudes toward the bottom 13 from the same position. On the other hand, the above-mentioned notches of the kneading blades 15, 15 are arranged on the inner surface of the drum body 12, and cement, aggregate, etc. pass through the flow holes h formed by these notches, and the notches of the kneading blades 15, 15. They are designed to be able to flow reciprocally from one side to the other or from the other side to one side.

The rotating drum of the concrete mixer truck according to the present invention is constructed as described above. Fresh concrete is put into the drum body 12 from the mouth 11, and the fresh concrete is stirred within the drum body 12 by rotating the drum body 12 in the normal direction. Transport while doing so.
At the concrete placement site, the drum body 12 is reversed to discharge the fresh concrete to the outside. Also, when performing wet mixing,
Water, cement, fine aggregate, coarse aggregate, etc. are each weighed in a concrete batcher plant and put into a drum body 12, and the drum body 12 is rotated forward at a high kneading speed to mix. At that time, water, cement, etc. are transferred to the blade 1 as the drum body 12 rotates.
4, 14 and kneading blades 15, 15, and when the position reaches a certain height, it collapses downward due to gravity and is mixed by convection to become fresh concrete. At this time, water, cement, etc. move back and forth through the flow holes h of the kneading blades 15, 15 and do not remain in one place, which improves kneading performance and helps prevent separation. Moreover, once the ready-mixed concrete is made, it is then stirred and transported or discharged in the same manner as described above.

Therefore, the rotating drum of the present invention has the kneading blades 15, 15 equipped with flow holes h in the main part extending from the center part to the bottom part 13, and the height of the blades 14, 14 in the main part is lower than that of the kneading blades 15, 15 in the main part. Since it is formed to be more bulky, the kneading efficiency is increased, and the kneading time, which conventionally required about 15 minutes, is shortened to about 5 minutes. Further, the tip of one of the blades 14 on the bottom 13 side is connected to the extension member 1.
4b is longer than before, so the mixing balance is lost when the fresh concrete is stirred, and the fresh concrete is always shaken, which is effective in preventing cement, aggregate, etc. from sticking to the bottom 13 side. Furthermore, since the kneading blades 15, 15 and the blades 14, 14 are both formed in substantially the same shape based on the conventional blade 4, it is possible to modify the conventional rotating drum to make it as in the present invention. is also easy. In this case, a part of the conventional blade 4 can be cut to form the above-mentioned raising member 14a and extension member 14b, and the remaining part can be used as the kneading blade 15, which can be cut out at a predetermined location and attached to the drum body 12.

As explained above, according to the rotating drum of the present invention, wet mixing can be performed extremely efficiently and the kneading time can be significantly shortened. Further, since the structure is simple, it is easy to manufacture a new one, and since the blade type is almost the same as a conventional one, it can also be manufactured by modifying a conventional rotating drum.

[Brief explanation of the drawing]

FIG. 1 is an external view of a conventional rotating drum with the drum main body cut away. In addition, FIGS. 2 to 4 show an embodiment of the present invention, in which FIG. 2 is a schematic side view showing the arrangement of each blade, FIG. 3 is a schematic front view of the raised blade, FIG. 4 is a schematic front view of the kneading blade. 12...Drum body, 13...Bottom, 14...
Blade, 14a... Raising member, 14b...
Extension member, 15...Kneading blade, h...Flow hole.

Claims (1)

[Scope of utility model registration request] A rotating drum of a concrete mixer truck in which blades are spirally provided on the inner surface of a conical drum body from the bottom to the mouth of the drum body, and the drum body is provided with flow holes from approximately the center to the bottom. A rotating drum for a concrete mixer truck, characterized in that a kneading blade is provided in a spiral shape, separate from the blade and substantially parallel to the blade.