JP3001387B2 - Kneading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a kneading apparatus for stirring and kneading various materials, for example, for effectively stirring and kneading different materials such as raw concrete material.

[0002]

2. Description of the Related Art There are the following three types of kneading apparatuses such as a concrete mixer for kneading cement, aggregate and water to produce a cement paste as a concrete material.

In a container rotating type (tilt type mixer), several blades are fixed to an inner wall of a cube type shape, a container is rotated, a material is lifted by the blade, and free fall by gravity. Is kneaded with a shearing force of Due to the gravity-dependent type, the efficiency is poor and the container-fixed type mixer has recently become mainstream.

In a fixed container type (bread type mixer), a plurality of paddles for kneading materials are fixed to a vertical axis in the center of a dish type container, and kneading is performed by rotating the axis.

[0005] Another container fixed type has a horizontal one axis and a two axis.
It is called a shaft type mixer, and has a horizontal axis at the center axis of a horizontal cylindrical container, and a plurality of paddles for kneading materials are fixed to this horizontal axis, and kneading is performed by rotating the shaft. I do.

[0006] The above-mentioned mixer of the container fixed type is currently the mainstream, but is kneaded only by the paddle because it is kneaded by shearing force due to the stirring of the paddle. Therefore, the circulation effect is poor and the kneading time is long. .

[0007] The above three types of mixers, when the number of revolutions is increased, cause co-rotation and scattering, thereby impairing the kneading force. There is a limit in the kneading force and kneading speed due to the mechanism.

Further, some of the single screw type mixers have been devised so as to uniformly knead the material charged in the container. As one of them, there is a proposal of a kneading apparatus as shown in FIG. In this conventional apparatus, a spiral screw 2 for stirring, which is vertically provided inside the kneading container 4, is coaxially surrounded so that the material effectively convects inside the container when the kneading material is stirred and kneaded. The draft tube 6 is fixedly mounted. In this kneading apparatus, when the screw 2 is rotated, the kneading material M charged into the kneading container 4 flows downward by the propulsive force of the rotating screw 2 as shown by an arrow in the figure, , And rises outside the draft pipe 6, enters the inside of the draft pipe 6 at the upper end of the draft pipe 6, and circulates by convection.

However, when handling highly viscous kneading materials,
The material in contact with the inner surface of the kneading container 4 or the outer surface of the draft tube 6 is prevented from flowing due to contact resistance. That is, in FIG. 6, the kneaded material tends to stay in the regions T1 and T2, and the mixing may be insufficient.

However, what is more problematic than this disadvantage is that the kneaded material inside the draft tube 6 adheres to the rotating screw 2 and rotates together. When this co-rotation, which is an idling phenomenon, occurs, the kneaded material does not flow and falls into a kneading impossible state. This is particularly noticeable when the viscosity of the material to be kneaded is high.

The co-rotation of the kneading material with the screw as described above can also occur in a double screw type mixer.

For example, even in a double screw type mixer in which two spiral stirring screws are arranged side by side in parallel, the rotation direction of the two screws arranged in parallel may be the same or opposite. Even so, there is a possibility that the material in contact with the inner wall surface of the kneading container loses fluidity due to frictional contact with the wall surface and stays there. In some cases, also in this case, the kneading material may adhere between the screw blades and rotate together with the screw to make kneading impossible.

[0013]

As described above, the conventional kneading apparatus cannot not only stir and knead the kneaded material efficiently and homogeneously, but also causes the kneaded material to stay in the kneading container or to stick to the rotating screw. There were problems such as causing co-rotation.

For example, when kneading failure occurs when preparing a cement paste to be used as a material for lightweight concrete, agglomerates of cement particles with an internal pressure of air tend to be formed in the paste, and a so-called "dama" is generated. This "dama" is a source of defects on the order of microns within hardened concrete, creating a cause of reduced concrete strength. In order to avoid such inconveniences, it is necessary to knead the materials without fail. However, from the viewpoint of productivity, it has been desired to perform the kneading process efficiently in a short time as possible.

An object of the present invention is to provide a kneading apparatus capable of rapidly and efficiently kneading a kneading material and uniformly stirring and kneading without causing a kneading defect.

Another object of the present invention is to effectively agitate and knead the kneaded material without causing the stagnation of the kneaded material in the kneading vessel at the time of kneading, or causing inconvenience such as co-rotation caused by sticking to the kneading screw. To provide a kneading apparatus.

Another object of the present invention is to provide a kneading container having a shape and a stirring means such that the kneading material does not stay in the kneading vessel during the kneading operation or adhere to the rotating stirring means to cause co-rotation. Is to provide a kneading device in which the components are arranged.

Still another object of the present invention is to drive the inner stirring means and the outer stirring means which are provided coaxially in a kneading vessel in order to stir and knead the kneading material quickly and uniformly, and to efficiently rotate and drive. An object of the present invention is to provide a kneading apparatus provided with a system.

[0019]

In order to achieve the above object, a kneading apparatus according to the present invention comprises an inner stirring means vertically suspended at the center of a kneading vessel having a lower half inner wall having an inverted truncated cone shape or a half spindle shape. And an outer stirring means rotating along the inner wall of the kneading vessel, and a drive system for independently rotating and driving the inner stirring means and the outer stirring means.

The inner stirring means is constituted by a spiral screw having blades extending in a vertical direction and inclined at an angle in one direction, and this is rotated in one direction so that the kneading material in the center of the kneading vessel is kneaded. Is propelled upward and outward.

The outer stirring means includes a flow straightening plate having an angle with respect to the radial direction of the container, and a stirring member having blades inclined in a direction opposite to the angle of the blades of the screw and extending vertically. The kneading material in the kneading vessel is propelled and flowed inward by a flow straightening plate having an angle with respect to the radiation direction of the kneading vessel, and the kneading material around the inner wall is caused to flow downward and inward by a stirring member.

The circulating convection moves upward and downward around the center of the kneaded material in the kneading vessel by the upward and outward propulsion of the material by the inner stirring means and the downward and inward propulsion of the material by the outer stirring means. At the same time, a high-pressure portion where the kneading material collides in a high-pressure state at an intermediate portion between the center portion and the peripheral surface portion is formed over the outer periphery of the inner stirring means.

When the kneaded material collides in a high pressure state, shear friction occurs between the material particles to crush the bubble-like particles and to apply a forcible binding force between the material particles, so that the mixing of the materials is actively promoted. At the same time, the repulsive force exerts a wave-like impact on the material which tends to stick between the blades of the screw as the inner stirring means, thereby preventing the material from staying. Therefore, the mixing effect of the materials in the high-pressure section is greatly improved, and the efficiency of kneading the kneaded materials without causing a kneading defect is remarkably improved, and the stagnation of the materials in the screws is eliminated. Inconvenience such as co-rotation can be prevented.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a kneading apparatus for efficiently producing a good mixture by effectively stirring and kneading a kneading material. Here, a cement paste (concrete paste) which is a concrete material is conveniently used. )), Cement, aggregate (fine aggregate, coarse aggregate), water, etc. necessary for the production are assumed as kneading materials, but the materials to be kneaded are not limited.
It goes without saying that the present invention can be applied to stirring, kneading, dispersion, kneading, and the like of various materials.

The kneading apparatus shown in FIGS. 1 to 3 as one embodiment of the present invention comprises a kneading vessel 10, an inner stirring means 20 rotatably suspended at the center of the kneading vessel 10, and an inner stirring means. And an outer agitating means 30 rotatably provided on the outside of the apparatus 20.

The kneading container 10 has a cylindrical shape as a whole, comprising a substantially cylindrical upper half 10a having an opening at the upper end, and a bottomed cylindrical lower half 10b having an inverted truncated cone shape or a half spindle shape. The upper end opening is closed by a lid 12 having a shaft hole 12a at the center.

The lid 12 is partially open and the opening is
A material input section is formed by being surrounded by 2b. Meanwhile, container 1
A discharge port 14 which can be arbitrarily opened and closed is provided at a lower portion or a bottom portion of the container 0, and a discharge play 16 is provided outside the container so as to surround the discharge port. That is, the kneading material is put into the container from the hopper 12b of the lid 12, and the kneaded material is taken out from the outlet 14 after the kneading process, so that the inside of the container 10 fixed in a standing state as shown in the figure is obtained. Can be put in and taken out of the kneading material, but the structure for charging and discharging the kneading material is not particularly limited.

The inner stirring means 20 includes a rotating shaft 22a penetrating through the shaft hole 12a of the lid 12 and a helical blade 2 inclined at an angle in one direction around the rotating shaft 22a.
2b. In the illustrated embodiment, the helical direction of the blade 22b is a left winding, that is,
When the screw 22 is rotated clockwise (in the direction of arrow R1 in FIG. 2) in the right-handed screw direction, an upward propulsive force is applied to the fluid (kneading material M charged into the container 10) in contact therewith. As a result, an upward flow along the axis indicated by an arrow f1 in FIG. 4 and an outward radiation flow indicated by an arrow f2 occur in the kneaded material M in the container.

Although a right-handed screw structure is employed here, it is needless to say that a left-handed screw structure in which the spiral direction is reversed may be used.

The inner stirring means 20 is driven to rotate by a driving means 26 including an electric motor connected to the upper end of the rotating shaft 22a.

The outer stirring means 30 includes a revolving member 32 which revolves along the inner peripheral surface of the container 10 and the inner stirring means 20.
And a rectifying plate 34 for turning the fluid outside to apply a propulsive fluid pressure inward to the fluid.

The swirling member 32 is configured to cause the kneading material M to be charged into the container 10 to flow in the direction opposite to the direction in which the inner stirring means 20 flows.
That is, as described above, the inner stirring means 20 is
Is propelled upward (f1) and outward in the radial direction (f2) along the means 20, whereas the pivoting member 32 is moved downward (arrow f in FIG.
(3 directions) and an inward centripetal direction (the same arrow f4 direction) to generate a propulsive action (FIG. 4).

The turning member 32 in this embodiment includes a cylindrical rotary shaft 321 disposed coaxially outside the rotary shaft 22 a of the screw 22, and a pair of arms 322 extending radially from the rotary shaft 321. The arm 322 includes a support member 323 hanging down from an outer end of the arm 322 and a stirring member 324 held by the support member 323.

The stirring member 324 is made of a plate material.
4a is curved and projected forward with respect to the turning direction (left rotation direction indicated by arrow R2 in FIG. 2) to form a blade portion (upper portion 324a), fixed to support member 323 at intermediate portion 324b, and lower portion 324c. Is tilted with respect to the normal from the axis of rotation so that the outside of the shaft is forward with respect to the turning direction and the inside is rearward with respect to the turning direction.

The inclination direction of the elements constituting the stirring member 324 may be opposite to that of the illustrated embodiment, and is at least opposite to the direction of propelling the fluid by the inner stirring means 20, that is, a function of propelling the fluid downward and inward. Should be fine.

The current plate 34 is provided for the purpose of generating a thrust force in the same direction as the thrust force generated in the centripetal direction (f4) generated by the turning member 32 by utilizing the space between the inner stirring means 20 and the turning member 32. Have been. Therefore, if there is no room between the inner and outer stirring means 20 and the turning member 32, the rectifying plate 34 may be omitted.

The outer stirring means 30 transmits the rotational power of the driving means 36 including an electric motor or the like to the power transmission means 37a, 37.
The rotation is driven by receiving through b.

Here, the driving means 26 of the inner stirring means 20
The driving means 36 of the outer stirring means 30 are constituted by independent electric motors, but these driving means are not limited to the constitution of FIG. That is, the rotational driving force of one electric motor is applied to the rotating shafts 22a and 321 through the respective power transmitting means and the decelerating means, and the appropriately controlled rotational power is applied to the inner and outer stirring means 20 and 30. Is also possible. In any case, any drive system may be used as long as the inner stirring means 20 and the outer stirring means 30 can be controlled to rotate at appropriate rotational speeds respectively determined in opposite directions.

The operation of the kneading apparatus having the above-described structure will be described.
The kneading material M charged at 0 is upward (f1) and outward (f2) by the propulsive force generated by the rotation of the screw 22 around the screw 22 of the inner stirring means 20.
While the swirling member 32 of the outer stirring means 30
, The fluid flows downward (f3) and inward (f4) by the propulsive force generated by the turning of the turning member 32 around. The propulsive force acting on the kneading material M in the centripetal direction (f4) is doubled by the current plate 34.

Accordingly, the kneading material M rises at the axial center of the cylindrical container by the propulsive force of the upper f1 and the lower f3, and descends around the container to cause a circulating convection that returns to the axial center again, and has the radial direction f2. Due to the propulsion pressure in the centripetal direction f4, the kneading material M is brought into a high-pressure state by colliding around the outside of the screw 22 (a high-pressure portion which is a region T in FIG. 4). In the high-pressure portion T, the reaction (expansion force) is instantaneously and repeatedly generated while the kneaded material M receives a strong compressive force. Therefore, the material particles repeatedly collide with each other, and the material of the kneaded material is different. Particles are forcibly combined and are intimately mixed.

Further, the repetition of the compression-expansion force of the material in the high-pressure portion T wave-likely affects the kneaded material M filled between the blades 22b of the screw 22, so that the material does not stick to the blades 22b and moves upward. The promotion flow is promoted. As a result, there is no inconvenience that the kneaded material having a high viscosity rotates together with the screw 22.

Further, since the stirring member 324 of the revolving member 32 revolves close to the inner peripheral surface and the bottom surface of the container, the material which tends to stay due to frictional contact on the inner peripheral surface of the container is peeled off from the peripheral surface of the container to remove the material. Since the material is pushed inward, the flow is not hindered, and the material smoothly convects and circulates throughout the container, so that a uniform kneading action is effectively received.

Thus, according to the kneading apparatus of the present invention,
Since the kneading efficiency can be dramatically improved, the required kneading time can be reduced and the quality of the kneaded product can be improved. Further, since the inner stirring means 20 and the outer stirring means 30 can be rotated at different rotation speeds, an optimum kneading state can be created according to the type of the material to be kneaded.

The inventors have experimentally manufactured several kneading apparatuses based on the concept of the present invention and confirmed the excellent effects. One of them is a kneading vessel 10 having a diameter of 650 mm and a height of 750 mm, an outer diameter of 240 mm, and a width 1 of the blade 22b.
There is a kneading device composed of a screw 22 having a diameter of 40 mm and a diameter / pitch ratio of 1: 1. Using this kneading apparatus, a comparative experiment with a conventional kneading apparatus was performed.

The conventional kneading apparatus used in the experiment was a forced biaxial type in which two stirring screws were arranged in parallel in a kneading vessel having the same volume as the apparatus of the present invention.

Three types of concrete materials shown in Table 1 were charged into each kneading container. That is, comparative samples # CS1 to #CS made of the blended materials shown in Table 1 were added to the conventional two-axis mixer.
CS3, and the mixer of the present invention was sample #E shown in Table 1.
S41 to # ES3 were given. The cement used is usually Portland.

[0047]

[Table 1]

In an experiment, the concrete material was kneaded by rotating the screw 22 of the mixer of the present invention at 300 rpm and simultaneously rotating the revolving member 32 of the outer stirring means at 30 rpm, whereas the screw of the conventional mixer was rotated at 45 rpm.
pm, and each stirring means was operated until each concrete material reached a target slump value.

The experiment shows that the minimum time required to obtain the target slump value is 60 seconds with the conventional mixer and 15 minutes with the mixer of the present invention.
Seconds were repeatedly determined in advance by experiments, and the characteristics (compressive strength of concrete after a specific time) of the cement paste obtained by kneading for the required time were considered. Table 2 shows the results of this experiment.

[0050]

[Table 2]

As is clear from Table 2, a comparison of the cement paste, which is approximately the same as the target slump value obtained after kneading each sample material for a predetermined time, shows that the kneading apparatus of the present invention kneaded only for 15 seconds. It has been found that the product can secure the same or better characteristics as the product kneaded for 60 seconds in the conventional apparatus.

Further, in order to obtain data supporting the effect of the kneading apparatus of the present invention, when a foaming agent was added to a concrete material such as cement and kneaded, fine air bubbles independent of the cement paste as a kneaded product were uniformly obtained. A dispersed state was obtained in a short time. When this was molded and cured, it was possible to obtain a lightweight and high-quality foam concrete structure exhibiting excellent water impermeability while maintaining a state in which closed cells were uniformly dispersed.

When a high-performance water reducing agent was added together with the foaming agent, the closed cells were further refined to about tens of μm, the dispersion was more uniform, and the strength was improved.

As still another attempt, when kneading cement using the kneading apparatus of the present invention, reinforcing short fibers (having a diameter of about 14
μm, about 6 mm length), a state was obtained in which the reinforcing short fibers were uniformly dispersed in the kneaded cement paste. Despite the fact that the aspect ratio of the reinforcing short fibers was about 428, mixing was confirmed at a rate of 1% or more per liter. When this was molded and cured, an extremely high-strength fiber-reinforced high-strength concrete in which short reinforcing fibers were uniformly dispersed was obtained.

Further, when the above-mentioned foaming agent, high-performance water reducing agent and reinforcing short fiber were all added to the concrete material,
A high-quality concrete paste having the above-mentioned excellent strength and properties was obtained. Thus, the kneading apparatus of the present invention can easily and highly efficiently knead materials that are difficult or impossible to knead with the conventional kneading apparatus, and effectively produce high-quality kneaded products. can do.

In the above-described embodiment, the outer stirring means comprises a pair of revolving members 32 extending in opposite directions from both sides of the rotating shaft 321. Basically, the balance is maintained around the rotating shaft 321. As long as the configuration is such that three or more pivot members can be provided. For example, when three turning members are applied, they may be arranged around the rotation shaft 321 at an angle interval of 120 degrees. There is no need to arrange them.

In the above-described embodiment, the rectifying plate 34 is provided between the screw 22 of the inner stirring means and the turning member 32 of the outer stirring means. However, as shown in FIG. An auxiliary turning member 432 having substantially the same configuration as that described above may be provided. By rotating the turning member 32 and the auxiliary turning member 432 together (R2) in reverse to the rotation (R1) of the screw 22, the inward propulsion pressure provided by the outer stirring means is increased, and the shearing friction of the kneaded material in the high-pressure section is increased. The effect increases.

Incidentally, the material of the components such as the kneading container and the screw in the kneading apparatus of the present invention can be appropriately selected depending on the material to be kneaded. It can be formed of a chemical material such as a ceramic or plastic material.

[0059]

As described above, according to the kneading apparatus of the present invention, a smooth vertical convection is generated in the kneaded material by the rotational driving of the inner stirring means and the outer stirring means, and both the stirring means are rotated in opposite directions. The high-pressure part can be formed by colliding the kneading material in the vertical direction during the high pressure part, and the high-pressure part itself can be used as a draft tube,
Since the circulation between the outside and the inside is guided along the inner wall at the lower part of the kneading container, the circulation efficiency can be dramatically increased. As a result, it is possible to stir and knead effectively without unevenness, so that it is possible to stir and knead quickly and uniformly irrespective of the kind of the kneading material. It does not cause inconveniences such as sticking together and causing co-rotation.

In particular, according to the present invention, by mixing the kneaded material from the inside and the outside in the vertical direction between the outside stirring means and the straightening plate and the inside stirring means,
Since a high-pressure state can be formed around the outer periphery of the outer stirring means, strong shear friction can be generated between the material particles. As a result, a large amount and uniformity of the bubble-like particles can be crushed, so-called "dama" can be eliminated, and at the same time, a forcible binding force acts between the material particles. Is actively promoted, and can be stirred and kneaded in a short time without unevenness.

[Brief description of the drawings]

FIG. 1 is a partially omitted schematic perspective view of a kneading apparatus of the present invention.

FIG. 2 is a side sectional view schematically showing the apparatus shown in FIG.

FIG. 3 is a plan sectional view schematically showing the apparatus shown in FIG. 1;

FIG. 4 is a conceptual diagram of a kneading apparatus of the present invention showing a flow state of a kneading material.

FIG. 5 is a schematic side view showing another embodiment of the kneading apparatus according to the present invention.

FIG. 6 is a schematic side view of a conventional kneading apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Kneading container 20 Inner stirring means 22 Screw 30 Outer stirring means 32 Revolving member 34 Straightening plate 321 Rotating shaft 322 Arm 323 Supporting member 324 Stirring member 324a Blade part (upper part) 324b Middle part 324c Lower part 432 Auxiliary rotating member

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model No. 1-156738 (JP, U) Japanese Patent Publication No. 62-49099 (JP, B2) Japanese Utility Model Publication No. Sho 54-10580 (JP, Y2) US Patent 2,298,317 (US) , A)

Claims (3)

(57) [Claims] 1. A kneading container having a lower half inner wall having an inverted frustoconical shape or a semi-spindle shape and receiving a kneading material; a kneading container vertically provided at a center of the kneading container and inclined at an angle in one direction and in a vertical direction. Inner stirring means comprising a helical screw having a blade extending over one side and rotating the material in the kneading vessel upward and outward by rotating in one direction;
The kneading container includes a blade that is inclined in a direction opposite to the angle of the blade of the screw and extends vertically, and rotates coaxially with the screw along an inner wall of the kneading container in a direction opposite to the rotation direction. Outer stirring means comprising a swirling member for propelling and flowing the material downward and inward; having an angle with respect to the radial direction of the kneading vessel, together with the outer stirring means between the inner stirring means and the outer stirring means. A rectifying plate that rotates to propel and flow the kneading material in the kneading container inward;
A kneading device comprising at least one drive system for independently rotating and driving the inner stirring means and the outer stirring means. 2. An agitating member having a blade portion formed by bending an upper portion of the agitating member toward the front in a swiveling direction, and being fixed to the support member at an intermediate portion, and an outer portion of the lower portion being swung in a swiveling direction. 2. The kneading apparatus according to claim 1, wherein the kneading apparatus is inclined in a plane with respect to a normal line from the rotation axis so that the inside of the feeder is forward with respect to the turning direction. 3. An auxiliary rotating member having the same structure as the rotating member is fixed to the outer stirring means, and the auxiliary rotating member is rotated between the inner stirring means and the outer stirring means together with the outer stirring means to rotate the auxiliary rotating member. The kneading apparatus according to claim 1, wherein the kneading material in the kneading vessel is propelled and flowed inward.