JPS6114852B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a cylindrical or partially cylindrical mixing vessel and a driven mixing mechanism rotating about its longitudinal axis, preferably extending horizontally. The present invention relates to a mixer supporting a mixing tool or radial arm whose shaft terminates at a small distance from the cylindrical inner wall of the mixing vessel.

In known mixers of this type, especially so-called plow mixers, i.e. mixers in which the mixing mechanism has a plow-spring mixer, there is the problem that deposits of the substances to be mixed accumulate on the inner walls of the mixing vessel. Hardened deposits can cause excessive tool wear and, in extreme cases, cause mixing mechanism failure.
The friction between the outer edge of the mixing device and the deposits on the inner wall may even make it impossible to start the mixing mechanism again after it has been stopped, if it exceeds the starting capability of the drive mechanism that operates the mixing mechanism.

The formation of deposits on the inner walls of the mixing vessel is undesirable as some of them break off during the mixing process and fall into the mixed material, resulting in non-homogeneous materials. If the mixing vessel is provided with wall heating means, the deposits of the mixed substance deposited on the walls will prevent the heat from the wall heating means from being transferred into the interior of the mixing vessel, resulting in a thick layer of deposits. The more it becomes, the greater the degree.

During operation, the mixing tool must be rotated at a distance from the inner wall of the mixing container to ensure that there is no contact between the mixing tool and the walls of the mixing container, so that the deposits of the mixed substance can be deposited on the inner wall of the mixing container. can be formed.

Although the formation of deposits can be substantially suppressed by special shapes of the mixing tool, especially its edges that rotate close to the walls of the mixing vessel, the formation of deposits can be avoided when mixing several substances. cannot be completely avoided. Traditionally, such deposits have only been effectively disposed of by frequent cleaning of the mixing vessel by manual separation and removal of any deposits that adhere to the interior walls of the mixing vessel. It was hot. However, this requires the mixer to be shut down for a long period of time, which is not desirable as it increases labor costs which substantially increases the operating price of the mixer. In particular, this type of cleaning method often does not comply with current regulations regulating operational safety and worker protection measures.

It is an object of the present invention to reduce any deposits of the mixed material that form on the inner walls of the mixing vessel or that deposits harden and wear out the rotating mixing implements or cause them to stop completely. The goal is to crush and separate them by a simple method using a mixing mechanism before they become powdery.

The mixer according to the invention comprises an at least partially cylindrical mixing vessel having a longitudinal axis and a mixing device rotating about said longitudinal axis and terminating at a small distance from the inner wall of said mixing vessel. a driven mixing mechanism supported on a directional arm; and means for rotatably mounting the central shaft to rotate on a central arc about the longitudinal axis of the mixing vessel.

Therefore, in the present invention, the shaft of the mixing mechanism is driven not only in rotation around its longitudinal axis, but also on an arc in which the mixing tool rotates concentrically with respect to the mixing vessel, and the rotating mixing tool The maximum approach position between the mixing container and the inner wall of the mixing container changes continuously. Therefore, a deposit of uniform thickness cannot be formed on the inner wall of the mixing vessel. Moreover, the mixer continuously acts on any thick deposits present to break them up and reduce or separate them from the walls before hardening. The reaction of the compositions in the mixed material that is prone to forming deposits continues for a period of time after contact of the compositions, and the reaction product hardens. This time can be minutes, but often hours. For this purpose, it is necessary that the position of the shortest distance between the rotating mixing tool and the inner wall of the mixing container pass through the circumferential surface of the mixing container at least once during the reaction period of the mixed substance. However, it is preferred that the shaft rotate at a rotational speed considerably lower than the rotational speed on the arc, so that the forward speed at the point of the shortest distance between the mixing tool and the inner wall of the mixing vessel is relatively small, resulting in The advantage is that any deposits are separated from the walls into relatively small pieces and can be homogeneously mixed with the mixed material again.

Because the distance between the rotating mixing tool and the inner wall of the mixing container varies everywhere and the position of the shortest distance shifts continuously, deposits tend to form in areas where the distance increases, but when the position of the shortest distance continuously shifts Because of the shearing, deposits are evenly scraped off almost immediately as soon as they form. As in known mixers, the mixing tool always rotates over the entire circumference of the mixing container at a certain distance from the inner wall of the mixing container, but there is a uniform gap between the rotating mixing tool and the inner wall of the mixing container. The formation of deposits can be prevented much better than in known mixers, since rings of deposits of a certain thickness cannot be formed. Due to the constantly changing distance between the rotating mixing tool and the inner wall of the mixing vessel, the deposits are separated and even the deposits that form in the area of the smallest distance are separated and the mixing tool and the wall of the mixing container are directly connected. It is crushed so that it is returned to the mixing process without contact. The concentrically rotating mixer constantly bites into any ring of sludge and breaks it up before it solidifies and hardens.

This minimum distance displacement must be small compared to the rotational speed of the shaft, but must be large enough to pass over the entire circumference of the mixing vessel at least once during the reaction time of the mixed product.

The radius of the arc around which the shaft rotates, and thus the eccentricity of this rotational movement, is preferably greater than the maximum bending of the shaft in the center, but not more than about 50 mm. This eccentricity may be a few millimeters and is preferably at least 20% of the average distance between the mixing device and the inner wall of the mixing vessel. This is achieved, for example, by mounting the shaft of the mixing mechanism in a bush with an eccentric passage. These bushes are held for synchronous or common rotation in the end wall of the mixing vessel and are provided with a drive mechanism. Problems in driving the eccentric rotating shaft can be easily solved by such a configuration.
This is because the connection between this shaft and a fixed drive motor or drive transmission can be achieved, for example, by a simple Cardan transmission.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below by way of example with reference to the accompanying drawings.

The mixer according to the invention has a closed cylindrical mixing vessel 1 with a horizontally extending longitudinal axis 2, which has a flange 5, which is bent at right angles at its lower end and thus serves as a support. It is fixed between two end plates 3, 4 with 6.
On the outside of the end plates 3, 4, bearing stands 7, 8, which are integral with them in the illustrated embodiment, are provided, respectively.

Inside the mixing vessel 1, a mixing mechanism is arranged, which consists of a horizontally arranged shaft 9 and a radially extending arm 10 fixed on this shaft. A latch-shaped mixing tool 11 or a partially latch-shaped mixing tool 12 is supported at the tip of each arm 10.
The longitudinal axis 13 of the shaft 9 is parallel to the longitudinal axis 2 of the mixing vessel 1 but offset by a distance e and rotates with this eccentricity on an arc of radius e.

This is achieved by mounting the shaft 9 in the region of each end plate 3, 4 in a bush 14, 15, respectively. These bushes 14, 15 each have an eccentric passage 16, 17 with eccentricity e. On the other hand, the bushes 14 and 15 are the bearing stands 7 and 8, respectively.
a toothed ring 2 rotatably mounted in the central passages 18, 19 of the mixing vessel 1 and shaped about a longitudinal axis coincident with the longitudinal axis 2 of the mixing vessel 1;
0,21 may be rotated by known methods, although not described in detail.

The mounting between the shaft 9 and the bushes 14, 15 and between the bushes 14, 15 and the bearing pedestals 7, 8 is achieved in the illustrated embodiment by ball bearings 22, 23, but with sealing rings. 24 and 25 are also provided.

Due to the eccentric mounting of the shaft 9, the area 26 between the inner wall of the cylindrical mixing vessel 1 and the mixing device 11, which is not covered by the mixing device, is not of uniform thickness but extends over the entire circumference of the mixing container. The thickness over the surface is particularly as shown in FIG. However, since the shaft 9 is not only mounted eccentrically with respect to the longitudinal axis 2 of the mixing container 1 but also continuously rotates on an arc concentric with the longitudinal axis 2 with an eccentricity e, the rotating mixing tool Since the position 27 of the shortest distance between 11, 12 and the inner wall of the mixing container 1 moves along the inner wall of the mixing container 1, deposits of uniform thickness are not formed anywhere on the circumferential surface of the mixing container 1. I don't get it. On the contrary, the thickness of the space allowing the formation of deposits varies continuously from a minimum to a maximum depending on the rotation of the shaft 9 on an arc around the longitudinal axis 2 of the mixing vessel 1. As soon as the sludge is formed, it is always reduced again, separated and crushed. The sludge cannot harden or solidify in any way, so that even if the sludge falls into the mixed material, it can immediately mix homogeneously with a large amount of material, so that the sludge does not adversely affect the mixing. There isn't.

[Brief explanation of the drawing]

FIG. 1 of the accompanying drawings is a longitudinal cross-sectional diagram through both ends of an embodiment of a mixer according to the invention, and FIG. 2 is a cross-sectional view of the mixer shown in FIG. 1... Mixing container, 2, 13... Longitudinal axis,
3, 4... End plate, 5, 6... Flange, 7, 8...
...bearing stand, 9... shaft, 10... arm, 11, 12...
...Mixing tool, 14,15...Butsuyu, 16,17
...Eccentric passage, 18, 19...Central passage, 20,
21... Toothed ring, 22, 23... Ball bearing,
24, 25...Sealing ring, 26...Area not covered by the mixing tool, 27...Position of the shortest distance.

Claims (1)

Claims: 1. An at least partially cylindrical mixing container having a longitudinal axis and a radial arm rotating about the longitudinal axis and terminating at a short distance from the inner wall of the mixing container. A mixer comprising: a driven mixing mechanism having a central shaft supporting a mixing tool; and means for mounting the central shaft for rotation in a concentric arc about the longitudinal axis of the mixing vessel. 2. The mixer according to claim 1, wherein the shaft rotates at a rotational speed substantially lower than the rotational speed at which the shaft rotates on an arc. 3. The mixer of claim 2, wherein the rotational speed is about 1% to about 6% of the rotational speed of the shaft. 4. The mixer of claim 1, wherein said circle has a radius greater than the maximum bend of the shaft and not more than about 50 millimeters. 5. Claim 4, wherein said radius is at least 20% of the average distance between the mixing tool and the inner wall of the mixing container.
The mixer described in section. 6. A mixer according to claim 1, wherein the shaft is mounted in a bush having an eccentric passage, the bush being mounted to rotate synchronously in the center of the end wall of the container. 7. The mixer according to claim 1, wherein the axis extends in a horizontal direction.