CN107139337A - A kind of vertical shaft type dither mixer - Google Patents

Abstract

A vertical shaft type high-frequency vibration mixer, including a vibration drive unit, a stirring drive unit, a mixing drum, a stirring device and a vibrator; the vibration driving unit and the stirring drive unit are fixed above the mixing drum; device, the center of the upper cover of the mixing drum is provided with a hole, and the upper end of the stirring device is coaxially arranged in the hole; the inside of the mixing drum below the hole is provided with an exciter, and the exciter is connected to the vibration drive unit through the connecting shaft of the exciter; The drive unit is connected to the upper end of the stirring device; the exciter is a polygonal solid shaft or hollow shaft with N smooth protrusions in the cross section, N is greater than 2, and its center of mass coincides with the center of rotation; the generated excitation frequency is linear to the number of protrusions N Positive correlation, changing the height of the protrusion can adjust the amplitude of the exciting force. The invention breaks through the limitation that the excitation frequency of the existing vibrating mixer cannot be increased, further reduces the friction force between molecules, and ultimately greatly improves the macroscopic and microscopic quality of concrete.

Description

A Vertical Shaft Type High Frequency Vibration Mixer

technical field

The invention belongs to the field of forced stirring equipment, in particular to a vertical shaft high-frequency vibration stirring machine.

Background technique

In recent years, my country's national economy has continued to develop, and domestic infrastructure construction has also continued to advance; cement concrete, as an important material in infrastructure construction, has higher and higher performance requirements during construction. However, at present, the concrete produced by ordinary mixers gradually shows shortcomings such as excessive cement consumption and cracking in the actual application process, which seriously affects the service life of the corresponding infrastructure.

Studies have shown that the concrete produced by ordinary mixers is uniform on the macro scale, but on the micro scale, the cement particles in the concrete still have 10%-30% agglomeration. It is precisely because of the existence of these aggregated particles that the contact area between cement particles and water is reduced, and the hydration reaction is incomplete, which ultimately affects the workability and strength of cement concrete. In addition, the main arrangement of the mixing blades of the existing vertical shaft forced mixer is planetary. This kind of mixer has the advantages of no dead zone in the mixing process. Poor.

At present, there are vibrating mixers on the market. The stirring shaft of this forced vibrating mixer is provided with a vibrator. During operation, the vibration and stirring of the vibrator act together on the mixture to improve the mixing quality of the mixture. In order to achieve the purpose of fully improving the mixing quality of the mixture, the vibrating mixer needs a high-frequency exciter, and the vibration frequency of the existing mixer is linearly related to the speed of the exciter. If the vibration frequency is simply increased by increasing the speed of the driving end Instead of using the new vibration excitation method, the bearing supporting the vibration shaft is prone to heat, which shortens its lifespan dramatically, which greatly limits the vibration frequency of the mixer, and ultimately leads to the inability to fully utilize the advantages of vibration and stirring. In addition, the existing form of the exciter makes the structure of the vibrating mixer more complicated.

Contents of the invention

The object of the present invention is to provide a vertical shaft type high-frequency vibration mixer to solve the above-mentioned problems in the stirring process.

To achieve the above object, the present invention adopts the following technical solutions:

A vertical shaft type high-frequency vibration mixer, including a vibration drive unit, a stirring drive unit, a mixing drum, a stirring device and a vibrator; the vibration driving unit and the stirring drive unit are fixed above the mixing drum; device, the center of the upper cover of the mixing drum is provided with a hole, and the upper end of the stirring device is coaxially arranged in the hole; the inside of the mixing drum below the hole is provided with an exciter, and the exciter is connected to the vibration drive unit through the connecting shaft of the exciter; The drive unit is connected to the upper end of the stirring device;

The exciter is a polygonal shaft with N smooth protrusions in cross section, and N is greater than 2; the exciter is a solid shaft or a hollow shaft, and the center of mass of the exciter coincides with the center of rotation.

Further, a second support bearing is provided between the hole edge of the mixing drum and the stirring device; a first support bearing is provided on the inner side of the stirring device, and the first support bearing and the second support bearing are on the same horizontal plane; the connecting shaft of the exciter passes through Set through the center of the first support bearing.

Further, when the stirring device moves, the mixture can be lifted; the stirring device is arranged around the vibrator.

Further, a rack is provided at the bottom of the mixing drum.

Further, the frequency f of the exciter=N×rotational speed of the exciter/60.

Compared with the prior art, the present invention has the following technical effects:

When the mixer of the present invention is mixing cement concrete, the vibration exciter with N convex polygons arranged on the rotation center of the mixing device rotates at a high speed. Every time the vibration exciter rotates once, the N protrusions force the mixture to vibrate N times, thereby The excitation frequency of the mixer is greatly increased, which breaks through the limitation that the excitation frequency of the existing vibration mixer cannot be increased, and further reduces the internal friction between molecules, so that the cement aggregate particles that are difficult to be destroyed by stirring can be dispersed faster under the action of vibration, increasing the The contact area between cement particles and water is enlarged, so that the hydration reaction can be carried out more fully, and finally the mixing quality of concrete, especially its microscopic quality, can be greatly improved, and the mixing time can be greatly shortened at the same time.

In addition, compared with the existing vibrator, the vibration exciter involved in the present invention can increase the vibration frequency by changing the number of protrusions instead of the rotation speed of the shaft of the exciter, and can also adjust the vibration by changing the height of the protrusions. Amplitude, even multiple amplitudes on the same exciter at the same time; at the same time, the center of mass of the exciter coincides with the center of rotation, and no exciting force will be generated on the supporting bearing during high-speed rotation, which optimizes the stress state of the bearing, making The service life of the bearing is greatly improved.

The vibration generating principle of the mixer of the present invention is simple, thereby simplifying the overall structure of the mixer.

Description of drawings

Fig. 1 is the schematic diagram of the structural principle of mixer;

Figure 2 is a schematic cross-sectional view of a vibrator with different numbers of bumps;

Figure 3 is a schematic diagram of the principle of vibration generation.

Among them: 1-mixing drum, 2-first support bearing, 3-exciter connecting shaft, 4-vibration drive and transmission unit, 6-stirring drive unit, 8-second support bearing, 9-stirring device, 11- Shaker, 12-rack.

detailed description

The present invention is further described below in conjunction with accompanying drawing:

Please refer to Fig. 1 and Fig. 2, a kind of vertical shaft type high-frequency vibrating mixer, comprises vibration driving unit 4, stirring driving unit 6, mixing drum 1, stirring device 9 and vibrator 11; Vibrating driving unit 4 and stirring driving unit 6 They are all fixedly arranged above the mixing drum 1; the inside of the mixing drum 1 is provided with a stirring device 9, the center of the upper cover of the mixing drum 1 is provided with a hole, and the upper end of the stirring device 9 is coaxially arranged in the hole; the inside of the mixing drum 1 below the hole is arranged There is an exciter 11, and the exciter 11 is connected to the vibration drive unit 4 through the exciter connecting shaft 3; the stirring drive unit 6 is connected to the upper end of the stirring device 9;

The vibrator 11 is a polygonal shaft with N smooth protrusions in cross section, and N is greater than 2; the vibrator 11 is a solid shaft or a hollow shaft, and the center of mass of the vibrator 11 coincides with its rotation center.

A second support bearing 8 is arranged between the edge of the hole of the mixing drum 1 and the stirring device 9; the inside of the stirring device 9 is provided with a first support bearing 2, and the first support bearing 2 and the second support bearing 8 are on the same horizontal plane; The connecting shaft 3 passes through the center of the first support bearing 2.

When the stirring device 9 moves, the mixture can be lifted; the stirring device 9 is arranged around the vibrator 11 .

A frame 12 is arranged at the bottom of the mixing drum 1 .

The frequency f of the vibrator 11 =N×rotational speed of the vibrator/60.

Working principle of the present invention:

1) Fill a certain ratio of materials into the mixing drum 1, start the vibration driving unit 4 and the stirring driving unit 6, respectively drive the vibration exciter 11 to rotate at a high speed and the stirring device 9 to rotate at a low speed;

2) Stirring device 9 continuously lifts and pushes the mixed material to the vibrator 11; at the same time, the vibrator 11 rotates at a high speed, forcing the mixed material wrapped around it to generate high-frequency vibration, so that the vibration and stirring act on the mixed material at the same time;

3) After the stirring is completed, the vibration driving unit 4 and the stirring driving unit 6 are turned off.

Referring to Fig. 3, assuming that the mixture at a certain position is closely attached to the lower position between two adjacent projections of the vibrator at a certain moment, the distance between the mixture at this position and the center of rotation is H ₀ , After the vibrator rotates through a certain angle, the mixture at this place is located directly above the protrusion, and the distance from the center _of rotation is H1 at this time; when the exciter rotates through the same angle again, the mixture at this place Under the extrusion of the peripheral mixture, it moves in the radial direction to another lower position on the vibrator, at this time the distance from the rotation center becomes H ₀ again; in this process, due to the rotation of the vibrator The speed is much higher than the stirring speed, so this process takes a very short time, and the surface of the vibrator is very smooth, so the mixture at this place basically does not move along the direction of rotation of the vibrator during this process, and the mixing at this place The movement of the material can be simplified as only moving along the radial direction of the exciter, and the movement distance is ΔH=H ₁ -H ₀ ; therefore, when the exciter rotates at a high speed, the movement of the mixture here can be regarded as a Vibration, and when the exciter rotates one circle, the number of vibrations of the mixture at a certain position is equal to the number N of protrusions distributed on the exciter, then the excitation frequency of the exciter can be expressed as: f=N× The speed of the exciter/60; it can be seen that the frequency of the exciter can be increased by increasing N, which is different from the traditional mixer that can only increase the frequency by increasing the speed of the vibration shaft. In addition, the amplitude can be adjusted by changing ΔH, and even the same exciter can achieve different amplitudes at the same time.

Further, with the continuous rotation of the vibrator, the positions of the protrusions are constantly changed, so the material wrapped anywhere around the vibrator can vibrate.

Claims (5)

1. a vertical shaft type high-frequency vibration mixer is characterized in that, comprises a vibration drive unit (4), a stirring drive unit (6), a mixing drum (1), a stirring device (9) and an exciter (11); Both the driving unit (4) and the stirring driving unit (6) are fixedly arranged above the mixing drum (1); a stirring device (9) is arranged inside the mixing drum (1), and a hole is arranged in the center of the upper cover of the mixing drum (1) , the upper end of the stirring device (9) is coaxially arranged in the hole; the inside of the mixing drum (1) below the hole is provided with a vibrator (11), and the vibrator (11) is connected to the vibration drive shaft (3) through the vibrator. The unit (4) is connected; the stirring drive unit (6) is connected to the upper end of the stirring device (9); The exciter (11) is a polygonal shaft with N smooth protrusions in cross section, and N is greater than 2; the exciter (11) is a solid shaft or a hollow shaft, and the center of mass of the exciter (11) and its center of rotation coincide. 2. A kind of vertical shaft type high-frequency vibration mixer according to claim 1, is characterized in that, the second supporting bearing (8) is arranged between the edge of the hole of mixing drum (1) and the stirring device (9); The inner side of (9) is provided with the first support bearing (2), and the first support bearing (2) and the second support bearing (8) are on the same horizontal plane; the exciter connecting shaft (3) passes through the first support bearing (2) ) center setting. 3. A vertical shaft type high-frequency vibration mixer according to claim 1, characterized in that the mixing device (9) can lift the mixture when it moves; the stirring device (9) is arranged around the vibrator (11). 4. A vertical shaft type high-frequency vibration mixer according to claim 1, characterized in that a frame (12) is arranged at the bottom of the mixing drum (1). 5 . A horizontal high-frequency vibration mixer according to claim 1 , characterized in that the frequency f of the exciter ( 11 )=N×rotational speed of the exciter/60.