JP2008290320A - Concrete mixer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concrete mixer capable of not only effectively preventing damages due to crack, abrasion wear or the like of its constituting members, such as mixing blades and considerably prolonging its life, but also reducing adhesion of ready-mixed concrete, moreover, capable of easily performing exchange work of the constituting members on damaging. <P>SOLUTION: The mixing blades 6a, 6b, 6c, 6d, 6e, 6f and 6g are formed from an elastomer, in the concrete mixer where a drive shaft 3 is installed in a required mixing vessel 1 so as to be able to be freely driven to rotate, and a required number of mixing blades 6a, 6b, 6c, 6d, 6e, 6f and 6g are radially mounted to the drive shaft 3 at a prescribed pitch through mounting arms 5. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a concrete mixer for use in producing raw concrete by mixing gravel, sand, cement, water, admixture and the like.

Conventionally, as this type of concrete mixer, for example, a biaxial concrete mixer disclosed in JP-A-56-155627, JP-A-2000-42391, or JP-A-2005-41113 is known. It has been. In such a biaxial concrete mixer, a pair of drive shafts on both sides are arranged in parallel in a required mixing tank so as to be freely rotatable, and each drive shaft is provided with a substantially spiral mounting arm. The mixing blades have a basic configuration in which the mixing blades are alternately mounted radially at a predetermined pitch. The mixing blades move the concrete material up, down, left, and right while moving the entire region in the mixing tank. -The raw material is kneaded to produce raw concrete.
Japanese Patent Laid-Open No. 56-155627 JP 2000-42391 A JP 2005-41113 A

By the way, the biaxial concrete mixer configured as described above exhibits sufficient kneading performance,
While the required raw concrete can be manufactured reliably, components such as mixing blades are made of a hard metal material such as cast steel in order to maintain the strength of the concrete mixer. It has the following problems.
First of all, since the biaxial concrete mixer is made of a metal material such as cast steel having a high hardness, it is very hard and has high strength, but it exhibits fragile properties and is used over time. It is easy to break and cause breakage. In addition, during kneading, concrete materials such as gravel are forcibly agitated and kneaded, so gravel and the like come into point contact with the outer surface and force is concentrated, which is worn with the properties of the material. It is easy.
Secondly, the outer surfaces of components such as mixing blades and mixing tanks formed of a metal material such as cast steel are always rough. For this reason, the raw concrete is likely to adhere to the outer surface and solidify, and as a result, the cleaning operation after the production of the raw concrete is very troublesome and troublesome.
Thirdly, when components such as mixing blades and mixing tanks are damaged by cracks or wear, they need to be replaced. At this time, since these components are made of a metal material such as cast steel, the weight is large and the handling is very inconvenient, and the replacement work is very difficult in combination with the work space in the narrow mixing tank. It is troublesome and time-consuming.

  The present invention not only solves the problems of the conventional example, but can effectively prevent the damage due to cracking or abrasion of the components of the concrete mixer such as mixing blades, and can significantly increase the life of the concrete mixer. An object of the present invention is to provide a concrete mixer that can significantly reduce the adhesion of raw concrete and can be easily replaced when damaged.

In order to achieve the above object, according to the first aspect of the present invention, a drive shaft is rotatably disposed in a required mixing tank, and a required number of mixing blades are attached to the drive shaft via a mounting arm. Is a concrete mixer in which the mixing blades are radially attached with a predetermined pitch, and the mixing blade is formed by an elastomer.

The invention according to claim 2 is characterized in that the lining layer made of an elastomer is formed on the inner peripheral surface of the mixing tank in the form of a lining, and the summary mixer according to claim 1 is characterized. is there.

The invention according to claim 3 is the gist of the concrete mixer according to claim 1, characterized in that at least the outer surface of the mounting arm is formed of an elastomer.

According to a fourth aspect of the present invention, a drive shaft is rotatably disposed in a required mixing tank, and a required number of mixing blades are radially attached to the drive shaft through a mounting arm at a predetermined pitch. In the resulting concrete mixer, the outer peripheral edge of the mixing blade is detachable,
The gist of the concrete mixer is characterized in that the outer peripheral edge is formed of an elastomer.

Since the invention according to claim 1 is configured as described above, it is possible not only to effectively prevent damage due to cracking or abrasion of the mixing blades, but also to significantly increase the life of the concrete mixer, -It is possible to perform the cleaning operation after kneading with extremely reduced adhesion of the toe, and since it is lightweight, even if it is damaged, the replacement operation can be performed easily and efficiently. It is possible.

Since the invention according to claim 2 is configured as described above, it is possible to effectively prevent damage due to cracking or abrasion of the inner surface of the mixing tank in combination with the mixing blade, and to significantly increase the life of the concrete mixer. Not only that, the adhesion of raw concrete is significantly reduced, and the cleaning operation after kneading can be performed very easily. Moreover, since it is lightweight, it can be easily replaced even if it is damaged. Can be performed efficiently.

Since the invention according to claim 3 is configured as described above, it is possible to effectively prevent damage due to cracking or abrasion of the mounting arm in combination with the mixing blade, and to significantly increase the life of the concrete mixer. Not only that, the adhesion of raw concrete is significantly reduced, and the cleaning operation after kneading can be performed very easily, and because it is lightweight,
Even if it is damaged, the replacement work can be easily and efficiently performed.

Since the invention described in claim 4 is configured as described above, it not only achieves the same effect as the invention described in claim 1, but also appropriately removes the outer peripheral edge of the mixing blade, which is particularly easily worn, as necessary. In other words, the life of the mixing blade itself can be significantly increased.

Hereinafter, the best mode for carrying out the present invention will be described in detail based on an embodiment shown in the drawings.

1 to 7 show an embodiment of the present invention. In the figure, reference numeral 1 is a cast steel mixing tank having a substantially semi-cylindrical shape, and 2 is a lining formed on the inner peripheral surface of the mixing tank 1. A pair of metal drive shafts 4 horizontally disposed at predetermined intervals in the mixing tank 1 to rotate and drive the elastomer lining layers 3 in opposite directions, and 4 rotate the drive shafts 3. A motor with a speed reducer 5 attached to the outside of the mixing layer 1 to be driven is a mounting arm composed of substantially spiral elastomers alternately attached to the pair of driving shafts 3 at a predetermined pitch. , 6a is the mounting arm
A mixing blade 7 made of a substantially plate-like elastomer, which is detachably attached to the front portion of the drum 5 with fastening members such as bolts and nuts, and 7 is a pair of mounting holes formed at the center of the mixing blade 6a. . In addition, 8 is a discharge gate attached to the bottom wall of the mixing tank 1.

As the elastomer for forming the lining layer 2, the mounting arm 5 and the mixing blade 6a of the mixing tank 1, a thermosetting elastomer or a thermoplastic elastomer is adopted and used. Such thermosetting elastomers and thermoplastic elastomers are lightweight and have excellent wear resistance. As an example of this, a urea type resin elastomer, which is a kind of the above-mentioned elastomer, is used in a taper type abrasion test (JI) frequently used for evaluating the wear resistance of resin-based materials such as plastics.
S7204-1999 and ISO9352) and the test results are shown in Table 1. Further, as a comparative example, the general structural rolled steel (SS40) and cast steel (Cr27) are also tested.
A bar-type wear test was conducted, and the results are also shown in Table 1. In Table 1, the wear index is obtained by indexing the wear volume when the general structural rolled steel is 1.0.

As is clear from Table 1, the urea resin elastomer is lightweight and has a large wear volume and the evaluation index is 0.06, whereas the rolled steel is 1.00 and the cast steel is 0.15. Resin elastomers have excellent wear resistance. This is presumably because the urea resin elastomer is lightweight and has high elasticity, so when it receives an external force, its power point is deformed and can be released by receiving a force on a larger surface. .

Further, the thermosetting elastomer and the plastic elastomer are highly elastic as described above, and the thermal expansion coefficient of the metal material such as concrete and cast steel is almost the same, but the elastomer is greatly different. Since the affinity is poor due to the difference in physical properties, the elastomer is presumed to be easily peeled off from the adhered concrete and can significantly reduce the adhesion of the raw concrete. .

Examples of the thermosetting elastomer include thermosetting elastomers such as phenol resin, urea resin, unsaturated polyester resin, epoxy resin, and polyurethane, acrylonitrile butadiene rubber, natural rubber, butadiene rubber, styrene butadiene rubber, Examples include isoprene rubber, butyl rubber, chloroprene rubber, acrylic rubber, epichlorohydrin rubber, ethylene propylene rubber, ethylene-propylene-diene copolymer rubber, or rubber-based thermosetting elastomer in which two or more of these are mixed.

Further, examples of the thermoplastic elastomer include polyurethane, polystyrene,
Polyester, polypropylene, polyethylene, nylon, polyvinyl chloride, polyvinylidene chloride, polybutene, polyacetal, polyphenylene oxide, polyvinyl alcohol
Rubber, polymethyl methacrylate, polycarbonate, polyarylate, aromatic polysulfone, polyamide, polyimide, fluororesin, ethylene-propylene resin, ethylene-ethyl acrylate resin, acrylic resin, norbornene resin, For example, a styrene copolymer represented by vinyl polyisoprene-styrene copolymer, butadiene-styrene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, polyurethane-based, polyolefin-based Examples thereof include thermoplastic elastomers, natural rubber, and synthetic rubber. These may be used alone, or may be mixed or copolymerized.

In the embodiment configured as described above, after a concrete material, such as aggregate or cement, weighed by a conventional method is put into the mixing tank 1, the motor 4 is started to drive the drive shaft 3 in a predetermined manner. The concrete material is moved in the mixing tank 1 while being moved up and down and left and right by the mixing blade 6a, and the concrete material is kneaded by the screw effect and the shearing action to produce the raw concrete. To manufacture At this time, since the lining layer 2, the mixing blade 6a, and the mounting arm 5 of the mixing tank 1 are each formed by a highly elastic elastomer, they receive an external force caused by a concrete material such as an aggregate. Even in the case, the deformation can escape the force point, so that wear can be effectively prevented. In addition, although the thermal expansion coefficient of raw concrete and metal materials such as cast steel are almost the same, the elastomer is greatly different, so the affinity is poor due to the difference in the physical properties, and the elastomer does not adhere to the adhered concrete. Since it is easy to peel off, the adhesion of the raw concrete is remarkably reduced, and the cleaning operation after the production of the raw concrete can be performed quickly and reliably and efficiently.

Even when the lining layer 2 or the mixing blade 6a of the mixing tank 1 is damaged due to use over time, it is lighter than cast steel and can be replaced even in the mixing tank 1 with a narrow space. The work can be performed very easily and efficiently.

8 to 10 show another embodiment of the mixing blade 6b, which is different from the above embodiment in that a reinforcing metal core 9 is embedded in the mixing blade 6b, and the other portions are the same. is there.

11 and 12 show another embodiment of the mixing blade 6c, which is different from the above embodiment in that the reinforcing plate 10 is mounted on the mounting surface of the mixing blade 6c, and the other portions are the same.

FIG. 13 shows another mixing blade 6d, 6e, 6f, and 6g of the present invention. FIG. 13A shows that the outer peripheral edge portion 12 is detachably attached to the front portion of the blade body 11 with a fastening member 13 such as a bolt. 13B shows that the outer peripheral edge 12 is detachably engaged with the tip of the blade body 11 by the engaging member 14, and FIG. 13C shows that the outer peripheral edge 12 is connected to the tip of the blade body 11 with the engaging member. FIG. 13D shows that the outer peripheral edge 12 is detachably connected to the tip of the blade body 11 via a connecting member 16 with an engaging protrusion. FIG. Unlike 6a, 6b and 6c, the other parts are the same.

The embodiment configured as described above not only has the same operational effects as the above embodiment, but also appropriately replaces the outer peripheral edge 12 of the mixing blades 6d, 6e, 6f, and 6g that are easily worn. The life of the mixing blades 6d, 6e, 6f, and 6g itself can be increased.

In the above embodiment, the mounting arm 5 is formed of an elastomer.
However, the present invention is not limited to this, and a coating layer made of an elastomer may be formed on the outer surface of a mounting arm made of cast steel, and the coating layer made of an elastomer is also formed on the drive shaft 3 in the same manner. It may be.
Furthermore, although the two-axis concrete mixer is shown in the above embodiment, the present invention is not limited to this. However, the present invention is not limited to this. It can be applied.

It is a perspective view which shows one Example of this invention. It is a cross-sectional view of FIG. It is a partially expanded sectional view which shows the mixing tank 1 of an Example. It is a perspective view which shows the mixing blade | wing 6a of an Example. It is a front view which shows the mixing blade | wing 6a of an Example. It is sectional drawing which follows the II line | wire of FIG. It is sectional drawing which follows the II-II line of FIG. It is a front view which shows the other mixing blade | wing 6b of an Example. It is sectional drawing which follows the III-III line of FIG. It is sectional drawing which follows the IV-IV line of FIG. It is a front view which shows the other mixing blade | wing 6c of an Example. It is sectional drawing which follows the VV line of FIG. It is a partially expanded sectional view which shows the other mixing blade | wing 6d * 6e * 6f * 6g of an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mixing tank 2 Lining layer 3 Drive shaft 5 Mounting arm 6a, 6b, 6c, 6d, 6e, 6f, 6g Mixing blade 11 Blade body 12 Outer peripheral edge

Claims (5)

In a concrete mixer in which a drive shaft is rotatably disposed in a required mixing tank, and a required number of mixing blades are radially attached to the drive shaft through a mounting arm at a predetermined pitch. A concrete mixer, wherein the mixing blade is formed of an elastomer. 2. The concrete mixer according to claim 1, wherein a lining layer made of an elastomer is formed on the inner peripheral surface of the mixing tank in a lining shape. 2. The concrete mixer according to claim 1, wherein the mounting arm has at least an outer surface formed of an elastomer. In a concrete mixer in which a drive shaft is rotatably disposed in a required mixing tank, and a required number of mixing blades are radially attached to the drive shaft through a mounting arm at a predetermined pitch. A concrete mixer characterized in that the outer peripheral edge of the mixing blade is detachable, and the outer peripheral edge is formed of an elastomer. 5. The concrete mixer according to claim 1, wherein the elastomer is a thermosetting elastomer or a thermoplastic elastomer.

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