JPH0362450B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a powder mixing device for homogeneously mixing different types of ultrafine particles when manufacturing a composite material using ultrafine particles of ceramic or the like as a raw material.

Conventional technology In general, devices for stirring and mixing powder and granular materials include those that rotate a container to stir and mix the powder and granular materials inside, and those that rotate rotary blades installed in a fixed container to mix the powder and granular materials inside. It is broadly divided into those that stir and mix.

The former type, in which the container is rotated, is a batch type and is difficult to operate continuously and is not suitable for stirring and mixing in large volumes, and is therefore not generally used.
In general, the latter type of stirring blade is often used, and known stirring blades include ribbon type, screw type, turbine type, and paddle type.

Problems to be Solved by the Invention As mentioned above, stirring and mixing of powder and granules is generally done by rotating stirring blades and using so-called mechanical stirring. When certain particulates are stirred with a stirring blade, the contact surface of the stirring blade is worn out, and a small amount of the worn particulates gets mixed in between the particulates of the product. Therefore, it becomes a problem if contamination is to be avoided.

In view of the current situation, the present invention provides a container rotating type mixing device that does not include a mechanical stirring device in the container in order to avoid contamination due to abrasion of stirring blades and achieve homogeneous mixing when stirring and mixing ultrafine particles. It is something.

Means for Solving the Problems The present invention provides an apparatus for mixing powder and granular materials by rotating a container using a mechanical rotation mechanism. The reason lies in the formation of spiral grooves that allow the particles to flow upward.

In this invention, the spiral uneven grooves formed on the inner wall surface of the container generate an upward vector due to the centrifugal force accompanying the rotation of the container, and if the powder can flow upward due to this, the inclination angle of the spiral I don't care. Further, the cylindrical portion is provided with an uneven groove so as to guide the spiral flow path in the conical portion gradually upward in the vertical direction.

Note that it is desirable that no grooves be provided in the upper part of the cylindrical part of the container in order to cause the granular material that has risen along the grooves to be reversed and lowered at the upper part of the container.

Effect: The container of the present invention has spiral grooves formed in the lower conical portion and grooves formed upward in the upper cylindrical portion to guide the concave and convex grooves upward. When the loaded container is rotated, centrifugal force is generated depending on the rotational speed, and based on this centrifugal force, an upward vector acts on the powder and granules, causing them to rise along the uneven grooves. Then, it rises while turning in the uneven grooves of the cylindrical part, and reverses at the upper end of the grooves.
Fall. The powder and granules falling from the entire circumferential surface of the cylinder form a vortex and fall while being mixed. Different types of powder and granular materials are uniformly mixed while repeating the swirling flow consisting of an upward flow along the uneven grooves of the rotating container and a falling flow inside.

Example Embodiments of this invention will be described based on the drawings.

The container 1 is made up of a conical part 2 and a cylindrical part 3, with the lower part of a cylindrical body narrowed into a conical shape, and uneven grooves 4 are provided on the entire circumference of the conical part 2 and the cylindrical part 3 except for the upper part. This uneven groove 4 is provided in a spiral shape, and the cylindrical portion 3
The lower part of is a spiral which is an extension of the spiral of conical part 2,
The helical angle gradually becomes smaller and forms a vertical groove in the upper part. A delivery port for taking out the uniformly mixed powder and granular material is formed at the tip of the conical portion 2, and is normally closed with a stopper 5. Further, an opening/closing lid 6 is provided at the upper end of the cylindrical portion 3 so as to be fixed with a lock 7.

The container 1 has a flange 8 protruding from the lower part of the cylindrical portion 3 connected to a rotation transmission joint 9 of a rotation drive device 11.
It is removably attached to via bolts 10.

The rotary drive device 11 has a drive shaft of a motor 15 connected to the lower end of a rotary shaft 14 that is vertically supported by a bearing provided in a bearing box 13 attached to the upper surface of a support frame 12, and a drive shaft of a motor 15 connected to the upper end of the rotary shaft 14. It is formed by joining a conduction joint 9.

Now, put 2 kg of ultra-fine barium sulfate and 2 kg of iron oxide into the container attached to the rotary conduction joint, close the lid, and drive the motor to rotate at a rotation speed of 500 times.
min and rotated the container for 10 min. Then, the container was removed from the rotational conduction joint, the stopper 5 was pulled out, and the powder was taken out. As a result of examining this mixed powder by magnifying it with a magnifying glass and examining it with a microscope, it was confirmed that the different types of powder were mixed uniformly.

Effects of the Invention In this invention, there is no stirring blade that rotates in contact with the powder in the container into which different types of powder and granules are charged, and when the container rotates, the powder and granules move through a spiral provided on the inner peripheral surface of the container. The swirling flow that rises and falls along the uneven grooves allows for uniform mixing during movement. As a result, there is no contamination of impurities due to wear of the stirring blades, etc., which is extremely effective in improving the quality of powdered products.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view of an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1, FIG. 3 is a cross-sectional view taken along line B-B in FIG. 1, and FIG. is a developed view of spiral grooves provided on the inner circumferential surface of the container. 1... Container, 2... Conical part, 3... Cylindrical part, 4
...Uneven groove, 5... Stopper, 6... Opening/closing lid, 7...
...Lock, 8...Flange, 9...Rotation transmission joint,
10...Bolt, 11...Rotary drive device, 12...
... Support frame, 13 ... Bearing box, 14 ... Rotating shaft, 1
5...Motor.

Claims (1)

[Claims] 1. In a device that mixes powder and granules by rotating a container using a mechanical rotation mechanism, the inner wall surface of the container is formed by constricting the lower part of a cylindrical body into a spiral shape that allows upward flow of the powder and granules. A powder/grain material mixing device characterized by forming uneven grooves.