JPH06227501A - Method and device for filling with low bulk density powder - Google Patents

Abstract

PURPOSE:To automatically fill a container with powder by operating a filling device for an optional time interval and with a stroke (falling distance) and obtain a specified uniform filling density regardless of the bulk density of the powder and further, reduce noises. CONSTITUTION:On driving a motor, a lifting plate 7 is raised through a lifting chain 6 and a driving power transmission system and an iron case 22 is lifted up. When an upper limit switch 10 preset at a required level is actuated thereby, it ceases to move up. When an electromagnet clutch is cut off by the signal from the upper limit switch 10, the iron case is lowered with the lifting plate by the gravitational falling, the iron case is flung on a fixed base 23 and a horizontal plate provided under the lifting plate as a unit collides with a hydraulic shock absorber 9. When the lifting plate actuates the lower limit switch 11, the electromagnetic clutch is returned to the connected state and the lifting plate is again raised and thereafter, it is repeated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low bulk density powder filling method and apparatus for filling a rubber mold or the like with powder of molybdenum or the like.

In this document, "rubber mold, etc." is referred to as "primary container",
"Iron case containing rubber mold, etc."
Either or both of the “primary container” and the “secondary container” may be collectively referred to as “container”.

[0003]

2. Description of the Related Art Conventionally, as an example, in the process of manufacturing a molybdenum sintered body, particularly when the product is large, the powder filled in the rubber mold is pressed by a hydraulic press in the preceding step,
The pressed body with the required shape is obtained. At this time, it is effective to increase the density of the powder in the rubber mold as uniformly as possible.

However, molybdenum powders generally have a low bulk density, and there are large variations in height depending on the particle size of the powders. Further, since molybdenum powder has poor fluidity, a sufficient packing density cannot be obtained by hammer ring of a case or vibration of a vibrator. In addition to this, in a pneumatic molding machine using compressed air (called a jolting machine and used when filling sand in a mold, etc.), the stroke of the cylinder is about 100 mm, and due to the mechanism. Since the number of times the cylinder is repeated causes a case dance phenomenon (caused by the case not following the cylinder), it is difficult to apply an appropriate force to powders with low bulk density, and sufficient filling density due to insufficient head drop. Can't get

As a method which does not use a machine, one or a plurality of workers may install an iron case 22 further containing a rubber mold 21 containing molybdenum powder, as shown in FIG.
500 from the iron fixing table 23 with concrete inside by human power
It was the actual condition that it was lifted up to a height of up to 600 mm and tapped a considerable number of times until the required packing density was obtained on the fixed table 23 by using gravity.

In this filling work, when the filling weight of molybdenum powder is 10 kg or more, the weight of the iron case 22 is 5 kg.
Since it will be more than 15 kg including,
Continuous work is difficult, and a large impact noise is generated when the iron case 22 is hit against the fixed base 23.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve the following problems by improving the drawbacks of the conventional techniques.

(1) It is possible to perform a powder filling operation into a container by automatically operating the filling device at an arbitrary time and stroke (falling distance) without requiring human power.

(2) The required uniform packing density can be obtained regardless of the bulk density of the powder.

(3) Noise can be reduced by constructing the filling device so that noise is unlikely to occur and by covering it with a soundproof cover.

[0011]

The present invention adopts the following means in order to solve the above problems.

(1) A powder such as molybdenum is housed in a container, and the height of the container is raised so that the powder can be packed into the container at a desired density by collision between the container and the fixing table due to free fall. And a method for filling a low bulk density powder, wherein the number of repetitions of rising and free fall of the container can be arbitrarily selected.

(2) The lifting limit of the lifting device is selected by a limit switch that can be set at an arbitrary position,
A container containing a powder of molybdenum or the like is provided with means for controlling the lowering limit of the lifting device by a limit switch that sets it to a predetermined position and optionally selecting the number of repetitions of lifting and lowering of the lifting device. The elevating device is provided with a portion for raising, a fixing base is arranged below the container to collide when the container falls freely, and a hydraulic shock absorber is arranged below the elevating device. A low bulk density powder filling device in which a sound-proof cover is used to control the ascending height of the elevating device and the number of repetitions of ascending and descending according to the bulk density of the powder by a program sequencer.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

(1) Rubber mold and iron case The powder filling container set in the lifting device of the filling machine is shown in FIG.
As shown in, a rubber mold (primary container) 21 containing molybdenum powder and an iron case (secondary container) 22 for holding the molybdenum powder and incorporating the molybdenum powder into the lifting device are provided. On both sides of the upper portion of the iron case 22, hook portions 24 are provided for pulling up by the lifting device.

(2) Main Structure of Lifting Device In FIG. 1, the power transmission system of the lifting device is composed of a gear motor 1 with a brake, an electromagnetic clutch 2, a chain and a sprocket 3, and a bearing 4.

The power transmission system of the lifting device is horizontally installed on a horizontal stand frame 5 as shown in FIG.

As shown in FIG. 2, the lifting device is arranged in a symmetrical structure so that the two left and right iron cases 22 can be simultaneously raised and freely dropped. The endless elevating chain 6 is installed in the vertical direction and interlocks with the chain and the sprocket 3. For the lifting chain 6,
The lifting plate 7 is fixed, and the lifting plate 7 has
As shown in FIG. 4, four pairs of front and rear guide rollers 8 are attached, and each guide roller 8 is in contact with the guide frame 5 in the vertical direction.
The movement in the front-back direction is restricted.

A hooking portion 24 of an iron case 22 is placed on the elevating plate 7, and a fixing table 23 is installed below the iron case 22. A horizontal plate integrally provided under the lifting plate 7 faces a hydraulic shock absorber 9 installed at the bottom of the filling device. An upper limit switch 10 is installed at a desired position of the stand frame 5 in order to regulate the rising limit of the lifting plate 7. The upper limit switch 10 emits a signal to disconnect the electromagnetic clutch 2. In addition, in order to switch the lifting plate 7 from lowering to rising, the lower limit switch 1
1 is installed at a predetermined position on the stand frame 5. The lower limit switch 11 emits a signal for connecting the electromagnetic clutch 2. An operation panel 12 is attached to the stand frame 5, and the periphery of the filling device is covered with a soundproof cover 13.

It should be noted that the rising height of the elevating device and the number of repetitions of ascent and descent according to the bulk density of the powder are input into the program sequencer in advance, and the optimum pattern is selected to perform the filling operation. You can also

(3) Method of Using Lifting Device and Operation The method of using the lifting device and its operation will be sequentially described below.

A Rubber mold 2 containing molybdenum powder
The iron case 22 further accommodating 1 is set on the fixed base 23.

B When the operation switch of the operation panel 12 is turned on, the geared motor 1 with brake is activated.

C When the motor 1 is started, power is transmitted through the power transmission system and the lifting chain 6, the lifting plate 7 rises, and the iron case 22 is pushed up.

D The lifting plate 7 stops rising when the upper limit switch 10 preset at a desired height position is opened or closed.

E When the electromagnetic clutch 2 is disengaged by the signal from the upper limit switch 10, the iron case 22 freely falls together with the lifting plate 7.

F The iron case 22 is struck against the fixed base 23, and the horizontal plate integrally provided under the lifting plate 7 collides with the hydraulic shock absorber 9 to absorb the shock.

When the lower limit switch 11 of the lifting plate 7 is opened or closed, the electromagnetic clutch 2 returns to the connected state, and the lifting plate 7 moves up again.

After that, the elevating plate 7 repeats ascending and descending, but the number of ascending and descending is set in advance by the operation panel 12.

(4) Experimental Data The rubber mold 21 containing 10 kg of molybdenum powder having a particle size of 4.5 μm is housed in a rectangular iron case 22 of 10 kg, and the experimental data when the height after target filling is 480 mm is shown in the table below. Shown in 1.

[0031]

[Table 1]

From this table, it is found that the conventional technique cannot fill the target filled height with molybdenum powder having a low bulk density. The target post-filling height refers to a size that is easy to handle in the subsequent hydraulic pressing process and sintering process because the molybdenum sintered body is formed to have a required size, but it is optional depending on the size of the iron case. It can be set to the height of, and is not necessarily uniform.

[0033]

According to the present invention constructed as described above, the following effects can be obtained.

(1) The power can be used to automatically operate the filling device at any time and at any stroke (falling distance) to perform the powder filling operation into the container.

(2) Whether the bulk density of the powder is low or high,
The required uniform packing density can be obtained.

(3) Except for the collision point between the secondary container such as an iron case and the fixed base, the filling device has a structure in which noise is unlikely to be generated, and since it is covered with a soundproof cover, noise can be reduced. it can.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the device of the present invention.

FIG. 2 is a front view of an embodiment of the device of the present invention.

FIG. 3 is a side view of an embodiment of the device of the present invention.

FIG. 4 is a perspective view of an embodiment of a rubber mold and an iron case used for implementing the present invention.

FIG. 5 is a perspective view of a conventional technique.

[Explanation of symbols]

 1 Geared Motor with Brake 2 Electromagnetic Clutch 3 Chain and Sprocket 4 Bearing 5 Guide Frame 6 Elevating Chain 7 Elevating Plate 8 Guide Roller 9 Hydraulic Shock Absorber 10 Upper Limit Switch 11 Lower Limit Switch 12 Control Panel 13 Soundproof Cover

Claims (7)

[Claims] 1. The height of the container is arbitrarily selected so that the powder can be contained in the container and the powder can be packed into the container to a desired density by collision between the container and the fixing table by free fall. And a method of filling a low bulk density powder, wherein the number of repetitions of rising and free fall of the container can be arbitrarily selected. 2. The method for filling a low bulk density powder according to claim 1, wherein the powder is molybdenum. 3. The lifting limit of the lifting device is selected by a limit switch that can be set to an arbitrary position, and the lifting limit of the lifting device is regulated by a limit switch that sets the lifting limit to a predetermined position. Is provided with a means for arbitrarily selecting the number of repetitions of, and a portion for raising the container containing the powder is provided in the lifting device,
A low bulk density powder filling device, characterized in that a fixing table is arranged below the container to collide with the container when the container falls freely. 4. The filling device for low bulk density powder according to claim 3, wherein the rising height of the lifting device and the number of repetitions of lifting and lowering are controlled by a program sequencer according to the bulk density of the powder. 5. The low bulk density powder filling device according to claim 3, wherein a shock absorber is arranged below the lifting device. 6. The filling device for low bulk density powder according to claim 3, 4 or 5, wherein the periphery is covered with a soundproof cover. 7. The filling device for low bulk density powder according to claim 3, 4, 5 or 6, wherein the powder is molybdenum.