JPH11221818A - Two-shaft concrete mixer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To knead a material in a short time by improving a conventional two-shaft mixer and improving furthermore kneading performance. SOLUTION: First arms 5 are stood on two parallel kneading shafts 3 and 3' arranged in a kneading tank 2 so as to arrange approximately spirally the first arms 5 in the shaft direction at specified intervals. The second arms 6 with an approximately same length as that of the first arms 5 are symmetrically stood at positions on approximately opposite sides of these first arms 5 to form the arms with two spirally arranged lines. On each of the first arms 5 and the second arms 6 being symmetrically stood, a large blade 7 with a size so as to overlap approximately the rotational locus of its adjoining blade end and a small blade 8 with a shorter length in the kneading shafts 3 and 3' than the length of the larger blade 7 are fitted. Kneading in a short time and uniformly is possible by providing chance of kneading of materials by means of both the large blade 7 and the small blade 8 while the kneading shafts 3 and 3' are rotated by one rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete mixer for producing ready-mixed concrete by mixing gravel, sand, cement, water, and an admixture, and more particularly to a forced-mixing concrete mixer having two mixing shafts.

[0002]

2. Description of the Related Art Biaxial concrete mixers are widely used in batcher plants for producing ready-mixed concrete. In this twin-screw mixer, two kneading shafts rotating in opposite directions are arranged in a kneading tank, and an arm having a feed blade attached to the kneading shaft is shifted at predetermined intervals in the axial direction by 45 to 90 degrees to form a spiral. It is configured to be arranged in a shape (screw shape). The material is moved over the entire area of the kneading tank while being fed up and down and left and right by feed blades having a rake angle and a rake angle, and the material is kneaded by its screw effect and shearing action.

[0003] In this conventional twin-screw mixer, the feed blade rotating along the side wall of the kneading tank is basically arranged in a single spiral around the kneading axis.

[0004]

Although the conventional twin-screw mixer has a sufficient kneading performance, the batcher plant equipped with the twin-screw mixer is a plant where shipment is concentrated at one time. For this reason, there is always a demand in the industry for a mixer with good kneading performance that can shorten the kneading time.

[0005] In view of the above, the present invention has been improved to the conventional twin-screw mixer to further improve the kneading performance so that the material can be kneaded in a shorter time than the conventional twin-screw mixer. The task is to provide

[0006]

Means for Solving the Problems Accordingly, the present inventors have:
In order to confirm that there is no more effective blade arrangement than a single spiral feed blade arrangement, the test was repeated while changing the arrangement of the blades of the twin-screw mixer, and as a result of intensive research, the opposite of the feed blade was found. It has been found that the kneading effect can be improved as compared with the conventional two-shaft mixer when the small blade is attached to the side position to form a double spiral blade arrangement.

That is, in the biaxial concrete mixer according to the first aspect of the present invention, two parallel kneading shafts rotating in opposite directions are provided in a kneading tank, and the respective kneading shafts are rotated around the respective axes. The first arm is erected so as to be spirally disposed at a predetermined interval in the axial direction while being shifted by a predetermined angle at a predetermined angle, and the first arm is substantially opposite to the first arm mounting position of the kneading shaft. A second arm of the same length is symmetrically erected to form a double spiral arm, and adjacent to the symmetrically erected first and second arms, respectively. A large blade having a size such that the rotation trajectories of the ends of the blades substantially overlap with each other, and a small blade having a length shorter in the kneading axial direction than the large blade are attached.

In the biaxial concrete mixer according to a second aspect of the present invention, the first arm and the second arm are spirally formed at predetermined intervals in the axial direction while being shifted by about 45 degrees around the kneading axis. The first arm, which is helically arranged, has large blades from one end of the kneading shaft to the vicinity of the center, and small blades from the vicinity of the center to the other end of the kneading shaft. At the same time, the second arm of the other spiral arrangement is provided with a blade having a size opposite to that of the blade of the symmetrically erected first arm.

[0009]

According to the biaxial concrete mixer according to the first aspect of the present invention, an arm having a double spiral arrangement is formed on the kneading shaft by the first arm group and the second arm group. The large blade and the small blade are attached to the symmetrically erected first arm and second arm, respectively, to form two spiral wings. Therefore, while the kneading shaft makes one rotation, both the large blade and the small blade give an opportunity to knead the material, and the screw effect and the shearing action of the two spiral blades composed of the large blade and the small blade provide the conventional effect. The kneading can be performed faster than the twin-screw mixer having a single spiral blade, and the speed of material discharge from the mixer can be increased to shorten the kneading time.

In addition, the large blade has a size and an arrangement in which the rotation trajectories of the adjacent blade ends substantially overlap, and the small blade is smaller than the large blade, so that the entire material is removed so that no material remains on the large blade. Kneading while moving, also gives a different change from the large blade of cutting into the material with small blades, so that not only the material is carried around, but also the more effective kneading by the interaction between the large blade and the small blade. It is possible to shorten the kneading time.

According to the twin-screw concrete mixer of the second aspect of the present invention, the two spiral blades are arranged in a dense state while being shifted by approximately 45 degrees each. A large blade is provided from one end of the kneading shaft to the vicinity of the center, a small blade is provided from the vicinity of the center of the kneading shaft to the other end of the kneading shaft, and the other spiral blade is provided with a blade having a size opposite to that described above. The blades attached to the kneading shaft of the book can be attached without contacting each other during rotation. In addition, the kneading is rapidly performed by increasing the chance of mixing by the two spiral blades and by rapidly moving the material to the left and right by the spirally arranged blades shifted by approximately 45 degrees.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 denotes a biaxial mixer for kneading materials such as gravel, sand, cement, water and an admixture to produce ready-mixed concrete. 3 '
And is rotatably supported by a bearing 4 fixed to the kneading tank 2.

The first arms 5 are erected on the kneading shafts 3 and 3 'so as to be substantially spirally (screw-shaped) at predetermined intervals in the axial direction while being displaced by about 45 to 90 degrees around the axes. I do.

A second arm 6 having substantially the same length as the first arm 5 is provided at a position substantially opposite to the first arm 5.
Are symmetrically erected. In addition, the first arm 5 and the second arm 6 are formed by one arm, which is
3 '. As described above, the first arm 5 group and the second arm 6 group form an arm having a double spiral arrangement.

At the tips of the arms 5 and 6 having the two spiral arrangement, large blades 7 and small blades 8 having blade shapes for mixing materials by a screw effect and a shearing action are attached.
The attachment of the large blade 7 and the small blade 8 is such that when the large blade 7 is attached to the first arm 5 symmetrically erected, the small blade 8 is attached to the second arm 6 at the other opposite position. When the kneading shafts 3 and 3 'make one rotation, each of the large blade 7 and the small blade 8 makes one rotation of the same material layer to mix the materials.

The large blades 7 are arranged such that the ends of the adjacent large blades 7, 7 are substantially overlapped when viewed from the vertical direction of the kneading shafts 3, 3 '. It is preferable that the rotation trajectories substantially overlap each other, so that the material can be moved over the entire area in the kneading tank 2 without scraping the material.

The small blades 8 are so sized that they do not come into contact with the large blades 7 of the kneading shafts 3 and 3 'facing each other when the kneading shafts 3 and 3' rotate, and that the mixer power does not become too large due to kneading load resistance. It is preferable that the length of the kneading shafts 3 and 3 ′ in the axial direction be shorter than that of the large blade 7. This small feather 8
Can be changed by cutting into a material different from that of the large blade 7, and the material is simply carried around by the shearing action at different positions due to the difference in size between the large blade 7 and the small blade 8. In addition, it is considered that more effective mixing can be expected due to the interaction between the large blades 7 and the small blades 8. If the large blades 7 and the small blades 8 inevitably come into contact with each other during the rotation of the kneading shafts 3 and 3 ', the mounting positions of the first arm 5 and the second arm 6 may be slightly shifted.

The first arm 5 and the second arm 6 to which the large blade 7 and the small blade 8 are attached have substantially the same length as described above, but the length is such that the attached large blade 7 and small blade 8 are kneaded. The length is such that it can rotate along the inner wall of the tank 2. Thereby, the peripheral speed of the small blade 8 is high, and the material on the inner wall side of the kneading tank 2 same as the large blade 7 is moved to assist the screw effect and the shearing action of the large blade 7, so that effective mixing can be expected.

A turning blade 9 for changing the moving direction of the material is attached to the first arm 5 at one end of the kneading shafts 3, 3 '. The large blade 7, the small blade 8, and the return blade 9 are attached at an angle of about 45 degrees with respect to the axial direction of the kneading shafts 3, 3 ', respectively. And move around the entire area of the kneading tank 2 while moving to.

The blade arrangement shown in FIGS. 1 to 3 is such that large blades 7 and small blades 8 are attached to arms 5 and 6 which are spirally displaced by about 45 degrees about the axes of kneading shafts 3 and 3 '. Is shown. With the two spiral blades shifted by approximately 45 degrees, the large blade 7 is attached to the first arm 5 from one end of the kneading shafts 3 and 3 'to the vicinity of the center, and the first arm 5 from the vicinity of the center to the other end. The small blade 8 is attached to the arm 5.

The second arm 6 has a large blade 7 and a small blade 8 which are opposite in size to the blades of the first arm 3 located on the opposite side. That is, if the large blade 7 is attached to the first arm 3, the small blade 8 is attached to the second arm 6, and if the small blade 8 is attached to the first arm 3, the second arm 6 is attached. The large wing 7 is attached to.

When the large blades 7 and the small blades 8 are attached to the kneading shafts 3 and 3 ', respectively, the large blades 7 and the small blades 8 of the opposing kneading shafts 3 and 3' are substantially opposed to each other. Attach 3 'so that the blades do not contact each other during rotation. If the large blades 7 and the small blades 8 inevitably come into contact with each other during the rotation of the kneading shafts 3 and 3 ', the mounting positions of the first arm 5 and the second arm 6 may be slightly shifted.

In the spiral blades shifted by approximately 45 degrees in this manner, a large blade 7 extends from one end of the kneading shafts 3 and 3 'to the vicinity of the center, and a small blade 8 extends from the vicinity of the kneading shaft to the other end of the shaft. If the spiral blades are formed, they can be arranged so as not to contact each other during rotation.

When the arms 5, 6 of the two spiral arrangement are shifted by 90 degrees around the kneading shafts 3, 3 ', the large blades 7 are attached to all of the first arms 5 and the second arms 5 are attached. Even if the small blades 8 are attached to all the groups of the arms 6, the large blades 7 and the small blades 8 attached to the respective kneading shafts 3 and 3 'facing each other during rotation can be arranged so as not to contact each other. It is conceivable, however, that the arrangement of the spiral blades on the way to the large blades 7 and the small blades 8 may be determined as appropriate.

Gears 10 and 1 are provided at one end of kneading shafts 3 and 3 '.
0 'is attached and fixed, and each gear 10,
The kneading shafts 3 and 3 'are rotated at a synchronous speed by meshing the kneading shafts 10'.

At the other end of the kneading shafts 3 and 3 ', sprockets 11 and 11' are mounted and fixed as a rotation transmission mechanism, and the sprockets 11 and 11 'and the driving motors 12 and 11' are fixed.
The sprockets 13, 13 ′ attached to the drive motors 12, 12 ′ are connected by chains 14, 14 ′.
By 2 ', the kneading shafts 3, 3' are rotated in the directions shown by the arrows in FIG.

The kneading shaft 3 of the twin-screw mixer 1
When the concrete material is put into the kneading tank 2 by rotating 3 ', the material is moved up and down, left and right by both the large blade 7 and the small blade 8, and the material is kneaded by the screw effect and the shearing action. In the two spiral blades, the kneading shaft 3,
During the rotation of 3 ', the large blades 7 and the small blades 8 provide an opportunity to mix and mix the materials, and the screw effect and the shearing action are increased as compared with the conventional single-screw twin-screw twin-screw mixer. Can also be mixed quickly. Also, the speed of discharging the material from the mixer is increased, and the kneading time can be reduced.

The large blades 7 have a size and an arrangement in which the rotation trajectories of the adjacent large blades 7 and 7 end substantially overlap with each other.
When the small blades 8 are smaller than the large blades 7, the large blades 7 mix the whole material while moving it so that no material remains, and the small blades 8 cut into the material.
Therefore, not only the material is carried around but also the more effective kneading is performed by the interaction between the large blades 7 and the small blades 8, and the kneading time can be shortened.

The inventors of the present invention conducted a kneading test of the twin-screw mixer according to the second aspect of the present invention using an actual machine. It was also confirmed that the kneading batch cycle was further shortened, and that a further increase in capacity could be expected. Also, the large blades 7 and the small blades 8 are arranged symmetrically, and the movement of the material in the surface layer portion is smooth because the two blades lift and move the material of the same layer near the inner wall of the kneading tank 2. Various effects were also confirmed, such as the phenomenon that the material hits the inner wall of the kneading tank 2 and scatters, thereby reducing the adhesion of the material to the inner wall of the kneading tank 2.

[0031]

As described above, in the twin-screw concrete mixer of the present invention, two parallel kneading shafts rotating in opposite directions are provided in the kneading tank, and each kneading shaft is rotated around the axis. The first arm is erected so as to be spirally arranged at a predetermined interval in the axial direction while being shifted by a predetermined angle, and substantially the same as the first arm on a side substantially opposite to the first arm mounting position of the kneading shaft. A second arm of length is symmetrically erected to form a double helical arrangement of arms and is adjacent to each of the symmetrically erected first and second arms. Since a large blade whose rotation trajectory at the blade end is almost overlapped and a small blade whose length in the kneading axis direction is shorter than that of the large blade are attached, the screw effect and shearing by the two spiral wings are provided. Mixes faster than conventional single-spiral blade twin-screw mixers It can, also material discharge spin from the mixer - can de even faster to shorten the kneading time.

The first arm and the second arm are erected at predetermined intervals in the axial direction while being shifted by about 45 degrees about the kneading axis, and are erected. A large blade is attached to the first arm from the one end of the kneading shaft to the vicinity of the center, a small blade is attached from the vicinity of the center to the other end of the kneading shaft, and the other arm of the other spiral arrangement is symmetrical. Since the blades of the size opposite to the blades of the first arm, which is installed upright, are attached, the blades attached to the two kneading shafts can be attached without contacting each other during rotation. The kneading is performed quickly by increasing the mixing chance by the spiral blades and by rapidly moving the material to the left and right by the spirally arranged blades shifted by approximately 45 degrees.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a biaxial concrete mixer according to the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a view taken in the direction of arrows AA in FIG. 1;

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 ... Biaxial mixer 2 ... Kneading tank 3, 3 '... Kneading shaft 5 ... 1st arm 6 ... 2nd arm 7 ... Large blade 8 ... Small blade

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akihiro Yamamoto 1-103-1 Eijima, Okubo-cho, Akashi-shi, Hyogo Inside Niko Corporation (72) Inventor Hiroyuki Sasaki 1-13-1, 1013 Eijima, Okubo-cho, Akashi-shi, Hyogo Nikko Corporation

Claims (2)

[Claims] 1. A kneading tank in which two parallel kneading shafts rotating in opposite directions are arranged, and are spirally arranged at predetermined intervals in the axial direction while being shifted by a predetermined angle around each of the kneading shafts. The first arm is erected so that a second arm having substantially the same length as the first arm is symmetrically erected on a side substantially opposite to the first arm mounting position of the kneading shaft. A large blade that forms a spirally arranged arm, and has a size in which the rotation trajectories of the adjacent blade ends substantially overlap each of the first arm and the second arm that are symmetrically erected, A twin-shaft concrete mixer, comprising small blades having a shorter kneading axial length than the large blades. 2. The apparatus according to claim 1, wherein the first arm and the second arm are erected at predetermined intervals in the axial direction while being shifted by about 45 degrees around the kneading axis. A large blade is attached to the first arm from the one end of the kneading shaft to the vicinity of the center, a small blade is attached from the vicinity of the center to the other end of the kneading shaft, and the other arm of the other spiral arrangement is symmetrical. 2. The two-shaft concrete mixer according to claim 1, further comprising a blade having a size opposite to that of the first arm.