JP2002018269A - Powder quantitative supply apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized powder quantitative supply apparatus for stably weighing a small amount of powder. SOLUTION: In the powder quantitative supply apparatus, a powder supply container is connected to one end of a powder supply pipe comprising a hollow pipe body, and a weighing device having a weighing volume space formed by boring a small volume space in the surface of a freely axially rotatable rod-shaped body is connected to the other end thereof and a vibration generator is mounted on the pipe side part of the powder supply pipe to take out a constant amount of the powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder feeding apparatus, and more particularly to a powder feeding apparatus which has a simple structure and can measure and feed a small amount of powder stably and quickly.

[0002]

2. Description of the Related Art Conventionally, methods for quantitatively supplying powder include a method of weighing using a weight sensor such as an electronic balance or a load cell, a method of measuring the volume by filling powder in a volume space, and a method of rotating. A method of scraping powder deposited on a table with a scraping plate or a method of extruding and discharging powder from a rotary screw has been used.

However, in the method of weighing powder using a weight sensor such as an electronic balance or a load cell, it takes a long time to perform an averaging process for dealing with weighing inability due to fluctuation inherent in the weight sensor and variations in the weighed value. It has been difficult to stably supply powder in units. Further, in a method of filling a volume space with powder and weighing the volume, it is difficult to make the filling density constant depending on the powder, and there is a case where the dispersion is large in terms of weight.

In a table system in which powder deposited on a rotating table is scraped off by a scraping plate or in a screw system in which powder is extruded and discharged, it is difficult to reduce the size and weight because a table or a screw is incorporated in the apparatus. It was difficult to incorporate into the analyzer.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and it is possible to repeat the operation of uniformly filling a small volume of powder and then discharging the powder in a short time, and to stably supply a constant amount of powder. An object of the present invention is to provide a powder quantitative supply device capable of supplying a body. It also meets recent needs for miniaturization and weight reduction.

[0006]

SUMMARY OF THE INVENTION The present invention has been made as a result of intensive studies in order to achieve the above object, and comprises connecting a powder supply container to one end of a powder supply tube composed of a hollow tube, thereby forming a rod-shaped member. A measuring instrument having a measuring volume space formed by perforating a small volume space on the surface of the powder supply tube is mounted so that it can rotate freely and shuts off the top and bottom of the powder supply tube. Vibration generator is installed in the measuring device, and the measuring volume space of the measuring device is positioned above, and the powder supplied from the powder supply container to the powder supply pipe is filled into the measuring volume space of the measuring device by the vibration of the vibration generating device. Then, rotate the measuring device to position the measuring volume space downward, drop the powder from the measuring volume space downward by the vibration of the vibration generator, and discharge the powder downward from the outlet of the powder supply pipe. To take out a certain amount of powder And to provide a quantitative powder supply device according to symptoms.

It is another object of the present invention to provide the above-mentioned fixed powder supply apparatus in which the vibration generated by the vibration device vibrates the powder supply pipe and the measuring instrument.

[0008] The vibration generator may be a piezoelectric vibrator, a magnetostrictive vibrator, an electromagnetic vibrator, a pneumatic vibrator or a rotary vibrator by a motor. Is to provide.

[0009]

According to the present invention, the powder is smoothly supplied to and filled in the measuring volume space of the measuring device by the vibration generating device, and the powder is filled into the measuring volume space of the measuring device by vibrating the measuring device by the vibration generating device. The powder corresponding to the volume of the measuring volume space is accurately measured.

[0010]

1 to 6 show an embodiment of the present invention.
This will be described with reference to FIG.

FIG. 1 shows a powder quantitative supply device 1 of the present invention. The powder quantitative supply device 1 includes a powder supply pipe 2, a measuring device 4 having a measuring volume space 3, a vibration generator 5, and an AC power supply 6. , A measuring device rotating device 7 and a powder supply container 8.

An upper portion of the powder supply pipe 2 is connected to a powder supply container 8, and a round bar-shaped measuring device 4 is rotatable in a circular hole formed at an intermediate portion of the powder supply pipe 2 at right angles to the pipe axis. It is inserted and inserted. In this case, as shown in FIG. 2, the inner wall of the powder supply pipe 2 is formed in a shape along the surface of the measuring device 4, and the upper and lower portions of the powder supply tube 2 are formed so as to be blocked by the measuring device 4. . As a result, the powder is stably moved and filled from the powder supply pipe 2 into the measuring volume space 3 of the measuring device 4, and the measuring volume space 3
After the powder is filled, the powder can be discharged by rotating the measuring device 4 by 180 degrees as shown in FIG.

A vibration generator 5 is provided on the side pipe of the powder supply pipe 2.

As the vibrator as the vibration generator 5, a piezoelectric vibrator, a magnetostrictive vibrator, an electromagnetic vibrator, a pneumatic vibrator, or a rotary vibrator using a motor can be used. In the case of a piezoelectric vibrator, an AC voltage is applied by an AC power supply 6 having a peak to peak voltage of 0 to 300 volts. Frequency is 2
A vibration frequency in the audible wave range of about 0 Hz to 1000 Hz is preferable, but 20 kHz to 2 kHz depending on the type of powder.
The vibration frequency in the ultrasonic range of 00 kHz may be used.

It is preferable that the vibration frequency of the vibration generator 5 can be selected according to the powder physical properties such as the particle size, adhesion and specific gravity of the powder.

The application time of the piezoelectric vibrator of the vibration generator 5 may be changed in a pulsed manner.

As shown in FIG. 2, the piezoelectric vibrator serving as the vibration generating device 5 can generate vibration such that the outer wall of the cross section of the powder supply pipe 2 causes radial vibration (r direction).

This vibration is a vibration with small attenuation, and oscillates the powder supply pipe 2 and the measuring device 4 inserted in the powder supply pipe 2.

The vibration generated by the vibration generator 5 propagates to the powder supply pipe 2 and the measuring device 4, and also to the powder supply container 8, and contributes to the operation of taking the powder into the powder supply pipe 2. .

As a piezoelectric vibrator of the vibration generator 5, as shown in FIG. 3, a ceramic PZT 9 having a thickness of 0.2 to 1 mm is sandwiched between electrodes 10 and 10 from both sides and a thickness of 0.1 to 0.3 mm is provided. A single plate (unimorph) in which the metal plates 11 are bonded together can be used. The ceramic expands and contracts by applying a voltage between the electrodes,
Since one side is attached to the metal plate 11, expansion and contraction of the attached surface is suppressed, and as shown in FIGS. 4 (A) and 4 (B),
The unimorph repeats the warping motion to generate vibration.

In FIG. 4, only one piezoelectric vibrator is provided. However, as shown in FIG. 5, if a sandwich type (bimorph type) in which two piezoelectric vibrators are laminated with a metal plate 11 interposed therebetween is used, the excitation vibration is further increased. Can be increased, the vibration transmitted to the powder supply pipe 2 and the powder meter 4 can be increased, and the filling efficiency can be increased.

Examples of the material of the powder supply pipe 2 include a metal material having a small vibration damping, polyacrylate, nylon, CFC, polycarbonate, polypropylene, and the like.
A plastic material with small vibration damping such as polystyrene is preferable.

The powder supply pipe 2 and the meter 4 are preferably made of fluorocarbon resin or the like, which is a low-friction material on the rotating contact surface. The powder supply pipe 2 and the measuring instrument which is inserted into the perforated portion of the powder supply pipe 2 and rotates. When the container 4 is made of fluorocarbon resin, the frictional resistance during the contact rotation is small and the rotation is performed smoothly, and the powder filled in the measuring volume space 3 may be peeled and discharged from the measuring device 4.

Further, the powder supply pipe 2 may be installed in an inclined state with the powder outlet side downward, but when the powder supply pipe 2 is set vertically, the falling gravity of the powder itself is effectively added, and the filling and discharging effects are improved. I do.

It is preferable that the center of the opening of the measuring volume space 3 of the measuring device 4 and the center axis of the hollow portion of the powder supply pipe 2 coincide with each other. If the structure does not flow out, the central axes do not necessarily have to be aligned.

The cross section of the powder supply pipe 2 does not necessarily have to be circular, and may have a structure having no opening other than the end face. The powder supply pipe 2 is preferably a straight pipe in order to reduce the flow resistance of the powder, but may be a curved pipe.

The powder supply pipe 2 and the measuring instrument 4 may be inserted and connected firmly so that the measuring instrument 4 can be rotated. However, the powder may be prevented from flowing out using an O-ring. good.

When a predetermined amount of powder is taken out by the apparatus of the present invention, the measuring device 4 having the measuring volume space 3 attached thereto is attached to the powder supply pipe 2 having the powder supplying container 8 connected to the upper portion. 4 is positioned in the upper hollow portion of the powder supply pipe 2.

In this state, the powder supply pipe 2 and the measuring volume space 3
When the measuring device 4 that has been processed is driven by the vibration generator 5, the powder supply pipe 2 and the measuring device 4 vibrate.

The vibration also propagates to the powder supply container 8, and the powder falls from the powder supply container 8 into the hollow portion of the powder supply pipe 2 and is continuously taken into the powder supply pipe 2. The powder taken into the powder supply pipe 2 fills the measuring volume space 3 of the measuring device 4 mounted on the powder supply pipe 2 by the vibration propagated from the inner wall surface of the powder supply pipe 2. Since the powder supply pipe 2 is hollow, the powder in the pipe has no escape route in the radial direction, and the powder taken in one after another is brought into a compressed state by vibration and pushed into the measuring volume space 3.

The powder continuously taken into the powder supply pipe 2 is subjected to a gravitational pushing force applied to the powder in a state where the frictional resistance between the powder and the inner wall is reduced by the flow effect of the vibrating wall surface. The powder pressed into the measuring volume space 3 of the measuring device 4 is compressed and press-fitted.

Next, when the position of the measuring volume space 3 of the measuring device 4 filled with the powder is rotationally moved downward, the powder is dropped and discharged downward by vibration.

If the applied power and the excitation frequency of the vibration generator 5 are kept constant, the volume 3 of the filled powder can be measured.
The bulk density is kept constant every time even if filling and discharging are repeated, and the weight conversion value is also constant.

The powder supply pipe 2 and the measuring device 4 are
Vibration applied to the measuring volume space 3 may be continuous during rotation.
Vibration may be limited only to the positions of filling and discharging, and may be stopped during rotation. Further, the rotation may be stopped for a certain time when the measuring volume space 3 reaches the powder filling position. Also,
The rotation may be stopped for a certain time when the measuring volume space 3 reaches the powder discharging position. The rotation speed may be freely determined.

[0035]

EXAMPLE An apparatus shown in FIG. 1 was manufactured using a powder supply pipe 2 and a measuring instrument 4 as a fluorocarbon resin. The powder supply pipe 2 has an outer diameter of 20.
The piezoelectric vibrator of the vibration generator 5 was press-contacted to the side of a tube having a diameter of 8 mm, an inner diameter of 8 mm, and a length of 40 mm.

The measuring device 4 has a round bar shape having an outer diameter of 10 mm and a length of 50 mm, and a hemispherical measuring volume space 3 having a diameter of 4 mm and a depth of 2 mm on the surface centered at 10 mm from one end. Was processed.

The diameter of the powder supply pipe 2 is
A millimeter hole is drilled, and the measuring device 4 is inserted so that the measuring volume space 3 of the measuring device 4 is located at the center of the hollow portion of the powder supply pipe 2 and mounted as shown in FIG. Is connected to a powder supply container 8 at one end of the powder supply pipe 2 so that the powder supply pipe 3 is vertical, and Gravity works.

A filling experiment was carried out into the measuring volume space 3 of the measuring device 4 by using powder of 82 percent of an aluminum oxide component having an average particle size of 10 microns.

The vibration generator 5 was set to a vibration frequency of 400 Hz, the voltage was excited at a peak-to-peak voltage of 200 volts, and the rotation of the measuring instrument 4 was made for 5 seconds. Weighed and measured.

The maximum filling amount is 0.065 g, and the minimum filling amount is 0.065 g.
052 grams, average fill was 0.059 grams.

[0041]

As described above, according to the present invention, the powder quantitative supply device in which the powder supply pipe and the measuring device are connected is excited by the vibration generator at a constant power and a constant frequency, and the powder is gravitationally moved. , And filling and discharging can be repeated to supply a fixed amount of powder quickly, stably and efficiently.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view of a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a longitudinal sectional view showing an example of an audible wave piezoelectric vibrator.

FIGS. 4A and 4B are longitudinal cross-sectional views illustrating warping vibration of an audible piezoelectric vibrator.

FIG. 5 is a longitudinal sectional view showing another example of the audible wave piezoelectric vibrator.

FIG. 6 is a vertical cross-sectional view of the powder weighing device in which a measuring volume space is moved.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 powder fixed quantity supply device 2 powder supply tube 3 measuring volume space 4 measuring device 5 vibration generator 6 AC power supply 7 measuring device rotating device 8 powder supply container 9 ceramic PZT 10 electrode 11 metal plate

Claims (4)

[Claims] 1. A measuring instrument having a measuring volume space formed by connecting a powder feeding container to one end of a powder feeding tube formed of a hollow tubular body and forming a small volume space in the surface of a rod-like body. It is rotatable and mounted so that the top and bottom of the powder supply pipe are shut off, and a vibration generator is arranged on the side of the powder supply pipe,
With the measuring volume space of the measuring device positioned above, the powder supplied from the powder supply container to the powder supply tube is filled into the measuring volume space of the measuring device by the vibration of the vibration generator, and then the measuring device is rotated. The metering volume space is positioned below, the powder is dropped from the metering volume space by the vibration of the vibration generator, and a certain amount of powder is taken out by discharging the powder downward from the outlet of the powder supply pipe. A fixed-quantity powder supply apparatus characterized in that: 2. The powder quantitative supply device according to claim 1, wherein the vibration generated by the vibration generator gives vibration to the powder supply pipe and the measuring instrument. 3. A powder supply container is connected upward with the powder supply pipe as a vertical direction, an intermediate position of the powder supply pipe is pierced, and the powder supply pipe is rotatable and vertically rotatable. When the measuring device consisting of a rod is inserted horizontally so as to shut off the powder, it is installed so that the measuring volume space of the measuring device is located in the hollow part of the powder supply pipe, and the powder is filled into the measuring volume space. Is located at the upper opening of the powder supply tube when the measuring volume space of the measuring device is positioned, and when the powder is discharged, the measuring device rotates and the measuring volume space is positioned at the lower opening portion of the powder supply tube and the powder falls. The powder quantitative supply device according to claim 1, wherein 4. The vibration generator according to claim 1, wherein the vibration generator is a piezoelectric vibrator, a magnetostrictive vibrator, an electromagnetic vibrator, a pneumatic vibrator, or a rotary vibrator formed by a motor, and is driven at an ultrasonic or audible wave frequency. The powder quantitative supply device according to 4.