JP2923147B2 - Powder processing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder processing method and apparatus for floating and transporting powder on a moving guide surface of a powder transporter or a powder feeder.

[0002]

2. Description of the Related Art In the pharmaceutical, metal, and food industries,
2. Description of the Related Art Various types of fine powder are often conveyed or supplied using a conveyor, a hopper, or the like. Conventionally, as a method for conveying and supplying such powder, there is a method using a vibrating conveyor. This vibrating conveyor gives a reciprocating vibration of a minute amplitude inclined at 20 to 30 ° to a moving guide surface of the powder, and continuously moves the powder or generates a phase difference to move or guide the powder. Things.

[0003] Vibration conveyors of this type usually have a frequency of 50 Hz
A vibration motor that generates a vibration wavelength in the audible range of about 1 KHz is used to apply high-speed linear vibration to a conveyor, a hopper, and the like.

[0004]

However, according to the conventional method using a vibrating conveyor, powder having a relatively large size in units of millimeters is jumped up from a moving guide surface of a conveyor or the like to be conveyed and supplied without adhering. However, there is a problem that fine powder having a size of several tens of microns or less adheres to the moving guide surface and easily remains without being detached even after repeated vibration.

[0005] Such residual powder on the moving guide surface causes mixing of the powder to be supplied next and the residual powder, particularly in the field of handling chemicals and the like, and causes various adverse effects. There are inconveniences. In addition to physical adhesion due to contact between the powder and the metal surface, various adsorption mechanisms such as electric adsorption, adsorption by activation or chemical reaction act on the adhesion of the fine powder. It is thought that it is.

[0006] In particular, for fine particles of several microns or less,
It is charged by the contact and friction between the powder and the metal surface during transport and by the contact and friction between the powders, and as the particles become smaller, the Coulomb force acting on the powder overcomes the gravity and the movement is significantly affected by static electricity. To receive. In addition, activation and chemical adsorption effects,
Adsorption due to ionization, adsorption due to wetting of the metal surface, and the like are likely to act, resulting in a state of being strongly attached to the moving guide surface. Therefore, in order to separate the fine powder once adhered to the moving guide surface, it is necessary to apply a force that overcomes the strong adhesion of the powder.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to make it possible to float and separate powder on a powder moving guide surface and to carry out powder efficiently and reliably. It is intended to provide a processing method and apparatus.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an ultrasonic vibration having a frequency higher than a predetermined frequency at which the powder can be suspended and conveyed on a moving guide surface of the powder and having a vibration displacement;
This is a powder processing method in which low-frequency vibrations below a predetermined frequency capable of conveying powder are synthesized and applied.

On the other hand, in the powder processing apparatus of the present invention, an ultrasonic vibrator and a low frequency vibrator are attached to a powder moving guide member,
The ultrasonic vibrator outputs ultrasonic vibrations at a frequency higher than the predetermined frequency at which the powder can be suspended and conveyed and vibration displacement, and the low frequency vibrator outputs low frequency vibrations at a predetermined frequency or lower to synthesize these vibrations. Further, the structure of a powder processing apparatus is provided in which control means for changing the output characteristics of the vibration wave of each vibrator are connected to each vibrator.

[0010] The moving guide surface is a surface for continuously moving powder, such as a surface of a conveyor or a chute, and the like.
The present invention is also applied to the inner wall surface of a hopper that temporarily stores powder and guides the movement thereof intermittently as needed.

[0011]

According to the powder processing method and apparatus of the present invention,
Ultrasonic vibration of a vibration displacement or more at a predetermined frequency or higher at which the powder can be suspended and conveyed to the moving guide surface of the powder, so that the falling speed of the moving guide surface exceeds the falling speed of the powder, thereby moving the powder. The contact time of the guide surface is reduced and the vibrating powder is decoupled from various electrical, chemical and other influences with the moving guide surface. As a result, the powder is separated and floated from the moving guide surface, the moving guide surface is cleaned, and the powder is conveyed.

[0012] In addition to the powder floating effect by the ultrasonic vibration, the powder conveying effect by the low frequency vibration is given to the moving guide surface, so that the separating force of the powder can be increased by the superposition effect. Therefore, efficient cleaning and transport of powder can be performed at a low power level.

[0013]

1 and 2 show a powder processing apparatus according to an embodiment. In the figure, reference numeral 1 denotes a Langevin vibrator formed by sandwiching a piezoelectric vibrator between elastic bodies. A step horn 2 is attached to a piston vibration end face of the Langevin vibrator 1, and a stainless steel A chute plate 3 made of a thin plate is attached.

The Langevin vibrator 1 is connected to a control device 5 for controlling an applied voltage and a current via a lead wire 4, and generates an ultrasonic wave generated by changing the voltage and the current applied to the vibrator 1. The intensity and frequency of the vibration can be changed. In this device, the displacement of the ultrasonic vibration generated by the Langevin vibrator 1 is
Is transmitted to the chute plate 3 during transmission. The chute plate 3 has a thickness of about 1 mm.
It is fixed to.

The confirmation of the detaching action of the powder using the above-mentioned apparatus A is as follows. First, the Langevin vibrator 1 and the chute plate 3 are inclined by 35 ° with respect to the horizontal plane, and the average particle diameter is several tens Then, the chute plate 3 was inclined at 70 ° with respect to the horizontal plane, and the Langevin vibrator 1 was operated in this state to ultrasonically vibrate the chute plate 3.

In the experiment, the chute plate 3 was excited by high-frequency ultrasonic vibration exceeding 20 KHz. However, when the applied voltage was low and the vibration displacement was small, the effect of the standing wave was generated, and a small amount of powder was deposited on the chute plate 3. The surface remained trapped in stripes.

On the other hand, when the electric input applied to the Langevin vibrator 1 is increased to increase the vibration displacement,
The powder floated off and detached from the surface of the chute plate 3 and oscillated on the surface of the chute plate 3 and gently flowed down from above. The vibration displacement at the tip of the step horn 2 at this time is 20μ.
m to 25 μm. In the device shown in FIG. 1, when the electric input is increased, a howling phenomenon occurs, and the chute plate tends to resonate. You may.

The apparatus B shown in FIG. 3 is such that a thin metal plate 13 connected to a Langevin vibrator 12 is opposed to an inclined moving guide plate 11 such as a hopper with a predetermined gap. Thin plate 13 fixed to this Langevin vibrator 12
Act acoustically as a baffle plate,
By resonating with 1, it functions as an ultrasonic sound source. That is, when the thin plate 13 is ultrasonically vibrated and acoustic radiation sound pressure is applied to the moving guide plate 11, the moving guide plate 11 resonates in a short distance range of about several centimeters, and the behavior of the powder by the radiated sound pressure is reduced. Can be operated.

In the experiment, the powder 14 was vibrated vigorously on the movable guide plate 11 by exciting the thin plate 13 by high-frequency, high-frequency ultrasonic vibration, and floated in the air at once. In this case, it is considered that a super breeze is generated due to vibration displacement on the surface of the moving guide plate 11 causing resonance, and it is considered that the powder floats in the air due to the fan effect.

On the other hand, the apparatus C shown in FIGS. 4 and 5 is an apparatus for cleaning powder by combining ultrasonic vibration and low frequency vibration. In this apparatus C, an ultrasonic vibrator 22 made of piezoelectric ceramics and two vibration motors 23 for generating low-frequency vibration of 100 Hz or less are mounted on the back surface of a chute plate 21 made of a thin metal plate. Control devices 24 and 25 for controlling outputs are connected to the vibration motor 23, respectively.

In the experiment, a long-wavelength vibration of 100 Hz or less is generated from the vibration motor 23 at a low level, and the vibration is applied to the chute plate 21 as a sine wave or a rectangular wave in an incident angle range of 20 to 30 ° in an impulse manner. Was. Then, with the electric input of the vibration motor 23 kept constant, the ultrasonic vibrator 22 was operated to apply ultrasonic vibration to the chute plate 21.

As a result, even when the electric input applied to the ultrasonic vibrator 22 is at a low level, the powder on the surface of the chute plate 21 floats up to particles of several microns or less and flows down the chute plate 21 while swinging. A phenomenon was observed. This is because the powder levitation effect by ultrasonic vibration and the powder transport effect by low frequency vibration are combined to float powder,
It is considered that the swinging force increased and the cleaning effect was greatly improved.

Further, when the rotations of the two vibration motors for exciting the low-frequency vibration are rotated in opposite directions, the transfer capability can be improved.

FIG. 6 shows a change in the amount of powder conveyed by the combination of the ultrasonic vibration and the low frequency vibration and the change of the amount of powder transported by the excitation by the ultrasonic vibration alone. It can be seen that there is much greater transport power and cleaning effect. Also, from the results of FIG. 6, when the synthetic wave is used, a large conveying force and a cleaning effect can be obtained even when the electric output applied to the ultrasonic vibrator or the vibration motor is low. Level, and the device can be reduced in size and simplified.

The device D shown in FIG. 7 has a step horn 32 connected to a Langevin vibrator 31 with the tip of 20-30.
Cut at an angle of degree, and a chute plate 34
Is attached. In the above structure, the tip of the step horn 32 to which the vibration is applied from the Langevin vibrator 31 excites the combined vibration of the longitudinal vibration and the transverse vibration of the ultrasonic wave.
When cut at an angle of two, two vibration waves of longitudinal vibration and transverse vibration are combined on the tip surface 33 with a phase shift of 90 °,
A composite wave is generated in which the amplitude peak moves with time.

For this reason, a traveling ultrasonic vibration is applied to the chute plate 34 fixed to the hole front end surface 33, and the powder supplied to the surface of the chute plate 34 is caused to float along the traveling direction of the vibration wave. It has the effect of being transported. That is, when the ultrasonic vibration which advances to the movement guide surface of the powder is given, the direction of the movement of the powder can be clearly controlled, and the transfer operation can be performed efficiently. In each of the above-described devices, when the breeze is sent along the moving guide surface, the powder trapped in stripes due to the standing wave of vibration is scattered, and the trap phenomenon can be eliminated.

Further, in each of the above-mentioned examples, the resonance phenomenon of the moving guide surface, the combination of the ultrasonic vibration and the low frequency vibration, or the combination of the proceeding ultrasonic vibrations can be combined to increase the powder conveying force. A floating force can be obtained, and efficient cleaning and transport can be performed.

FIG. 8 shows an example in which the present invention is applied to a hopper for supplying powder. An ultrasonic vibrator 42 made of piezoelectric ceramics and a vibration motor 4 for generating low-frequency vibration are provided on the side of the hopper 41.
3 is installed. The vibrator 42 and the vibration motor 43 may be mounted on a plurality of side surfaces of the hopper 41. In the example of FIG. 9, a cylindrical ultrasonic horn 52 is attached to a wall surface of a hopper 51. This structure has an advantage that the resonance level of the wall surface of the hopper 51 becomes constant.

FIG. 10 shows a medicine (powder) dispensing apparatus as an example of a powder processing apparatus. In the figure, 61 is a hopper for powder supply, 62 is a conveyor, and 6 is a conveyor.
3 is a V-mass disk for dispersing the powder, 64 is a distribution disk for averaging and depositing the powder, 65 is a scraping device for scraping the powder from the distribution disk 64 by a fixed amount, and 66 is a device for feeding the scraped powder to a medicine bag or the like. Hopper. In this distribution device, an ultrasonic vibrator or a vibration motor is attached to the hopper 61, the conveyor 62, and the hopper 66.

[0030]

As described above, the present invention provides powder by applying ultrasonic vibration having a frequency higher than a predetermined frequency capable of floating and transporting the powder on the moving guide surface of the powder and low frequency vibration lower than the predetermined frequency. Since the powder is floated and separated on the moving guide surface of the body and transported, it has a high ability to clean and transport the powder without remaining on the moving guide surface, and a powder transport and supply technology with excellent transport power is developed. There are effects that can be provided.

[Brief description of the drawings]

FIG. 1 is a front view showing an apparatus according to an embodiment.

FIG. 2 is a side view taken along the line II-II in FIG.

FIG. 3 is a diagram showing an apparatus according to another embodiment.

FIG. 4 is a diagram showing an apparatus according to another embodiment.

FIG. 5 is a rear view of the chute plate in the above device.

FIG. 6 is a graph showing a change in the amount of powder conveyed by a combined wave of ultrasonic vibration alone and low-frequency vibration.

FIG. 7 is a front view showing an apparatus according to another embodiment.

FIG. 8 is a perspective view showing an example applied to a hopper.

FIG. 9 is a perspective view showing another application example.

FIG. 10 is a diagram showing a medicine dispensing apparatus.

[Explanation of symbols]

 1, 31 Langevin vibrator 2, 32 Step horn 3, 21, 34 Chute plate 11 Movement guide plate 22, 42 Ultrasonic vibrator 23, 43 Vibration motor 41, 51 Hopper

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B65G 27/00-27/34

Claims (6)

(57) [Claims] 1. A method for floating and transporting powder on a moving guide surface of the powder.
Ultrasonic vibration with vibration displacement at or above a predetermined frequency to obtain
By synthesizing low frequency vibration below a predetermined frequency that can carry the body
A powder treatment method to be added. 2. A moving plan using the ultrasonic vibration as a radiation sound pressure.
The powder treatment according to claim 1, wherein the powder treatment is applied to an inner surface.
Method. 3. The powder processing method according to claim 1, wherein a resonance phenomenon is caused on the moving guide surface by the ultrasonic vibration. 4. The powder according to claim 1, wherein the ultrasonic vibration is obtained by synthesizing a plurality of vibration waves, and the peak of the amplitude of the synthesized wave moves with time. Processing method. 5. The powder processing method according to claim 1, wherein air is sent into the moving guide surface from inside. 6. An ultrasonic vibrator is provided on the powder moving guide member.
Attach frequency oscillator, ultrasonic oscillator floats and transports powder
Output ultrasonic vibration at a frequency higher than
And the low-frequency vibrator emits low-frequency vibration below a predetermined frequency.
Force each of the vibrators to combine these vibrations
Control means for changing the output characteristics of the vibration wave are connected to each vibrator.
A powder processing device formed by knotting.