JP2016221576A - Powder feeding device, and powder feeding method using the powder feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder feeding device which can stably feed a fixed amount of powder to a mold cavity.SOLUTION: A powder feeding device 1 to feed powder P to a mold cavity 15 comprises a powder box 31, a storage chamber shutter 32 and a control part 50. The powder box 31 includes a storage space 310 storing the powder P, and can move between a retreat position where an upper surface 1113 of a die 11 faces the storage space 310 and a powder feeding position where the storage space 310 communicates with the mold cavity 15. The storage chamber shutter 32 can perform switching between a closed state in which the storage space 310 is partitioned into a first storage chamber 313 and a second storage chamber 315 and an open state where the first storage chamber 313 and the second storage chamber 315 communicate with each other. The first storage chamber 313 is arranged on an upper side in a vertical direction, and the second storage chamber 315 is arranged on a lower side in the vertical direction and has a volume larger than the volume of the mold cavity 15. The storage chamber shutter 32 can divide and feed the powder P of the storage space 310 into the first storage chamber 313 and the second storage chamber 315.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a powder supply apparatus that supplies powder to a cavity, and a powder supply method using the powder supply apparatus.

  2. Description of the Related Art Conventionally, there is known a powder feeding device that supplies powder to a cavity that opens on an upper surface of a die used for compacting. A typical powder feeder includes a powder box that can move horizontally on the upper surface of the die so as to move forward and backward with respect to the cavity while containing powder. The bottom of the powder box is open, and the powder in the powder box is charged into the cavity when the bottom of the powder box overlaps the cavity. For example, Patent Document 1 discloses a feeder that can supply powder to a cavity, a hopper that is provided above the feeder in a vertical direction and that can supply powder to the feeder, and a shutter that can divide the feeder and hopper. Is described.

Japanese Utility Model Publication No. 63-192434

  In the powder feeding apparatus described in Patent Document 1, by closing the shutter, the weight of the powder in the hopper is prevented from acting on the powder in the feeder, and the amount of powder in the feeder is made constant. However, in the powder feeding apparatus described in Patent Document 1, since the upper side in the vertical direction of the feeder is open, when the feeder moves from the bottom of the hopper onto the cavity, the powder in the feeder moves in the feeder due to inertial force. However, the density distribution of the powder in the feeder may be biased, or the powder in the feeder may leak from the upper side in the vertical direction in the feeder. For this reason, the fluidity of the powder supplied to the cavity varies from shot to shot, and the density distribution and dimensional accuracy of the green compact after press molding may be deteriorated.

  The present invention has been made in view of the above-described problems, and is a powder feeding apparatus that can stably supply a certain amount of powder to a cavity, and a powder feeding that can stably supply a certain amount of powder to a cavity. It aims to provide a method.

The present invention is a powder supplying apparatus that supplies powder to a cavity that opens to the upper surface of a die that is used for forming a green compact, and includes a powder box, a storage chamber shutter, and a control unit.
The powder box has a storage space for storing powder, and is movable between a retracted position where the upper surface of the die faces the storage space and a powder supply position where the storage space communicates with the cavity.
The storage chamber shutter can be switched between a closed state in which the storage space is divided into a first storage chamber and a second storage chamber and an open state in which the first storage chamber and the second storage chamber communicate with each other. The first storage chamber is disposed on the upper side in the vertical direction, and the second storage chamber is disposed on the lower side in the vertical direction and has a volume larger than the volume of the cavity. The storage chamber shutter can separate the powder in the storage space into a first storage chamber and a second storage chamber.
The control unit controls the operation of the storage chamber shutter.

In the powder feeding apparatus of the present invention, the powder box moves from the retracted position to the powder feeding position and then returns to the retracted position, whereby one shot of powder feeding is completed.
According to the above configuration, when the storage chamber shutter is switched from the open state to the closed state in a state where the powder is stored in the storage space, the powder is cut out to the second storage chamber and the second storage in a state where the powder is filled. The room is partitioned. That is, the second storage chamber is filled with powder. As a result, when the powder box moves from the retracted position to the powder feeding position, the bias of the density distribution of the powder is less likely to occur due to the inertial force in the second storage chamber filled with the powder. Moreover, since the storage chamber shutter is in the closed state, the powder does not scatter to the outside from the second storage chamber.
Further, when the powder box is located at the powder supply position, since the storage chamber shutter is in the closed state, a certain amount of powder divided into the second storage chamber is supplied to the cavity.

  As described above, the powder feeding apparatus of the present invention can supply a certain amount of powder to the cavity for each shot while preventing the uneven density distribution of the powder in the second storage chamber. Thereby, since the fluidity | liquidity of the powder supplied to a cavity is stabilized, the powder supply apparatus of this invention can make the density distribution of the green compact after press molding constant, and can improve a dimensional accuracy.

Moreover, this invention is a powder supply method using the said powder supply apparatus, Comprising: A 1st process, a 2nd process, and a 3rd process are included.
In the first step, powder having a volume sufficient to fill the second storage chamber is supplied to the storage space of the powder box located at the retreat position.
In the second step after the first step, the storage space is partitioned into a first storage chamber and a second storage chamber by the storage chamber shutter.
In the third step, the powder in the second storage space is supplied to the cavity.

  In the powder supply method of the present invention, in the second step, the storage space is partitioned into a first storage chamber and a second storage chamber by the storage chamber shutter. Thereby, since the powder is filled in the second storage chamber, the powder in the second storage chamber is less likely to be biased by the inertial force when the powder box moves from the retreat position to the powder supply position. . Further, only a certain amount of powder divided into the second storage chamber is supplied to the cavity. Thereby, since the fluidity | liquidity of the powder supplied to a cavity is stabilized in the powder supply method of this invention, the density distribution of the green compact after press molding can be made constant, and a dimensional accuracy can be improved.

It is a schematic diagram which shows the powder supply apparatus by 1st Embodiment of this invention. It is a flowchart of the powder supply method to the cavity by 1st Embodiment of this invention. (A)-(b) is a schematic diagram for demonstrating the powder supply method to a cavity. (A)-(b) is a schematic diagram for demonstrating the powder supply method to a cavity. (A)-(c) is a schematic diagram which shows a mode that the storage tank of the powder feeder by 2nd Embodiment of this invention switches from a closed state to an open state. (A)-(c) is a schematic diagram which shows a mode that the powder box of the powder supply apparatus by 2nd Embodiment of this invention switches from a closed state to an open state, Comprising: The powder supply apparatus of a structure different from FIG. It is a schematic diagram which shows. It is a schematic diagram which shows the powder supply method to the cavity by other embodiment. It is a schematic diagram which shows the powder supply apparatus of a comparative example. It is a graph showing the thickness of the green compact in the powder supply apparatus by 1st Embodiment of this invention, and the powder supply apparatus of a comparative example.

  Hereinafter, powder supply devices according to a plurality of embodiments of the present invention will be described with reference to the drawings. Hereinafter, in a plurality of embodiments, the same numerals are given to the substantially same composition, and explanation is omitted.

[First Embodiment]
As shown in FIG. 1, the powder feeding apparatus 1 according to the present embodiment supplies powder as a raw material to a mold 10 used for molding a green compact. The mold 10 includes a die 11 having a mold hole, and a lower punch 12 and an upper punch (not shown) that can be inserted into the mold hole. By inserting the lower punch 12 into the die hole of the die 11, the cavity 15 opened in the upper surface 113 of the die 11 is defined.
The powder feeder 1 is installed with the vertical direction in FIG. 1 as the vertical direction, and the powder supplied from the powder feeder 1 is filled into the cavity 15 by its own weight. In this specification, for convenience of explanation, the lower side in the vertical direction and the upper side in the vertical direction are simply referred to as “upper side” and “lower side”.

  The powder supply apparatus 1 according to the present embodiment includes a storage tank 21, a first storage chamber shutter 22, a second storage chamber shutter 23, a powder box 31, a storage chamber shutter 32, a sensor 33, a powder box drive mechanism 40, and a control unit. 50 etc.

  The storage tank 21 has a storage space 210 in which the powder P can be stored, and a supply port 212 that can supply the powder in the storage space 210 to the powder box 31. Powder is continuously supplied to the storage space 210 of the storage tank 21 from, for example, a hopper (not shown).

The 1st storage chamber shutter 22 and the 2nd storage chamber shutter 23 are each provided in the storage tank 21, and can move with respect to the storage tank 21 with the drive source which is not shown in figure.
Specifically, the first storage chamber shutter 22 is in a closed state that partitions the storage space 210 into an upper first storage chamber 214 and a lower second storage chamber 216, and the first storage chamber 214 and the second storage chamber. The open state in which the chamber 216 communicates can be switched. For example, the second storage chamber 216 has a volume for storing the powder P corresponding to the amount of powder supplied to the cavity 15 in one shot.
Further, when the first storage chamber shutter 22 is switched from the open state to the closed state, the first storage chamber shutter 22 can be inserted into the storage space 210 in a state where the powder P is stored, and the powder P in the storage space 210 is inserted into the first storage chamber 214. And the second storage chamber 216 can be separated.

The second storage chamber shutter 23 is installed below the first storage chamber shutter 22 in the storage tank 21. The second storage chamber shutter 23 functions as a bottom portion of the storage space 210 that can be opened and closed, and shuts off and communicates with the second storage chamber 26 and the supply port 212.
When the second storage chamber shutter 23 is in the open state, the powder P in the storage tank 21 falls by its own weight and is discharged through the supply port 212.

  The powder box 31 has a storage space 310 in which the powder P can be stored. The accommodation space 310 is formed so as to penetrate the powder box 31 in the vertical direction. That is, the powder box 31 has an upper opening 311 and a lower opening 312 that communicate with the accommodation space 310.

Further, the powder box 31 is moved by the powder box drive mechanism 40 in a horizontal direction between a retracted position where the upper surface 113 of the die 11 faces the storage space 310 and a powder supply position where the storage space 310 communicates with the cavity 15. Is possible.
When the powder box 31 is located at the retracted position, the upper surface 113 of the die 11 functions as the bottom of the accommodation space 310. In addition, the storage space 310 can receive the powder P discharged from the storage tank 21 through the upper opening 311.
On the other hand, when the powder box 31 is located at the powder supply position, the powder P in the accommodation space 310 is supplied to the cavity 15 through the lower opening 312.

The storage chamber shutter 32 is provided in the powder box 31 and can be moved relative to the powder box 31 by a drive source (not shown).
Specifically, the storage chamber shutter 32 has a closed state in which the storage space 310 is partitioned into an upper first storage chamber 313 and a lower second storage chamber 315, and the first storage chamber 313 and the second storage chamber 315. It is possible to switch between the open state and the communication. The second storage chamber 315 has a volume larger than that of the cavity 15.
In addition, the storage chamber shutter 32 can be inserted into the storage space 310 in a state where the powder P is stored when switching from the open state to the closed state, and the powder P in the storage space 310 is inserted into the first storage chamber 313 and the first storage chamber 313. It can be divided into two storage chambers 315.

  The sensor 33 is installed in the powder box 31 and detects that the volume of the powder P in the accommodation space 310 is not more than a predetermined lower limit value. For example, the predetermined lower limit value is set to a value of a volume necessary and sufficient for the powder P to fill the second storage chamber 315. The detection result by the sensor 33 is transmitted to the control unit 50.

  The powder box drive mechanism 40 is a mechanism for driving the powder box 31, and a known technique can be used. For example, the powder box 31 can be driven when the rod 42 connected to the powder box 31 reciprocates in the cylinder 41.

  The control part 50 is comprised, for example with a microcomputer, and controls operation | movement of each member. Further, the control unit 50 can control the opening / closing operations of the first storage chamber shutter 22, the second storage chamber shutter 23, and the storage chamber shutter 32 based on the detection result of the sensor 33.

  Next, a method for supplying powder to the cavity 15 will be described with reference to FIGS. 2, 3 (a) to 3 (c), and FIGS. 4 (a) to (c). In FIG. 2, the flowchart of the powder supply method of the powder P is shown. 3A to 3C and FIGS. 4A to 4C, for convenience, the first storage chamber 313 and the second storage chamber 310 of the storage space 310 when the storage chamber shutter 32 is in the open state. The boundary with the storage chamber 315 is indicated by a dotted line L31, and the boundary between the first storage chamber 214 and the second storage chamber 216 of the storage space 210 when the first storage chamber shutter 22 is in the open state is indicated by a dotted line L21.

  First, in steps (hereinafter simply referred to as “S”) 101 as “first step” and “fourth step”, the second storage chamber 315 is filled with respect to the powder box 31 located at the retracted position. The storage tank 21 supplies a sufficient volume of the powder P. Specifically, the second storage chamber shutter 23 is opened while the storage chamber shutter 32 remains open. Thereby, the powder P in the second storage chamber 216 is discharged from the supply port 212 and supplied to the accommodation space 310 of the powder box 31. After the supply, the second storage chamber shutter 23 is closed (see FIG. 3A).

Next, in S102 as the “second step” and the “fifth step”, as shown in FIG. 3B, the open storage chamber shutter 32 is switched to the closed state, and the storage space 310 is changed to the first storage chamber. It is divided into 313 and a second storage chamber 315. Thereby, the powder P in the storage space 310 is cut into the first storage chamber 313 and the second storage chamber 315. At this time, the second storage chamber 315 is filled with the powder P.
In S102, the first storage chamber shutter 22 in the closed state of the storage tank 21 is switched to the open state. Thereby, the 1st storage chamber 214 and the 2nd storage chamber 216 are connected, and the 2nd storage chamber 216 is satisfy | filled with the powder P, as shown in FIG.3 (b).

Next, in S103 as “third step” and “sixth step”, as shown in FIG. 3C, the powder box 31 is slid on the upper surface 13 of the die 11 from the retracted position to the powder feeding position. (Outline arrow F3 in FIG. 3C). When the powder box 31 is located at the powder supply position, the second storage chamber 315 communicates with the cavity 15, so that the powder P in the second storage chamber 315 is put into the cavity 15 by its own weight.
In S <b> 103, in the storage tank 21, the opened first storage chamber shutter 22 is switched to the closed state, and the storage space 210 is partitioned into a first storage chamber 214 and a second storage chamber 216. Thereby, the powder P in the storage space 210 is cut into the first storage chamber 214 and the second storage chamber 216, and the powder P for the next supply is prepared in the second storage chamber 216.

  Next, in S104, as shown in FIG. 4A, the powder box 31 is slid and moved on the upper surface 13 of the die 11 from the powder feeding position to the retracted position (open arrow F4 in FIG. 4A). At this time, the powder box 31 grinds the powder P put into the cavity 15. Thereby, powder supply to the cavity 15 is performed.

  Next, in S <b> 105 as the “seventh step”, the powder is supplied to the first storage chamber 313 of the powder box 31. Specifically, as shown in FIG. 4B, the closed second storage chamber shutter 23 is switched to the open state. As a result, the powder P in the second storage chamber 216 is discharged from the supply port 212 and supplied to the powder box 31 located at the retracted position. At this time, since the storage chamber shutter 32 is in a closed state, the supplied powder P is deposited on the storage chamber shutter 32. That is, the supplied powder P is stored in the first storage chamber 313.

  Next, in S106, the first storage chamber 313 and the second storage chamber 315 are communicated. Specifically, as shown in FIG. 4C, the storage chamber shutter 32 is switched to the open state. Thereby, the first storage chamber 313 and the second storage chamber 315 communicate with each other, and the powder P in the first storage chamber 313 and the powder P in the second storage chamber 315 are combined and stored in the storage space 310. . The second storage chamber shutter 23 is switched from the open state to the closed state.

  As described above, the powder box 31 moves from the retracted position to the powder supply position, and then returns to the retracted position, whereby one shot of powder supply is completed. Further, when the powder box 31 returns to the retracted position, the powder P is supplied to the powder box 31. From the next supply, the process described with reference to FIGS. 3B to 3C and FIGS. 4A to 4C may be repeated.

  In the present embodiment, since the second storage chamber 216 stores the powder P corresponding to the amount of powder for one shot, the volume of the powder P stored in the storage space 310 after supply is the same as before supply. Is kept at the same level.

  In the above powder feeding method, when the first storage chamber 313 and the second storage chamber 315 communicate with each other (see, for example, FIG. 4C), the volume of the powder P in the storage space 310 is detected by the sensor 33. Is done. When it is detected that the volume of the powder P is equal to or lower than the predetermined lower limit value, the control unit 50 causes the first storage chamber shutter 22 and the second storage chamber shutter 23 to further supply the powder to the powder box 31. Open and close.

(effect)
In order to explain the effect of the powder feeding apparatus 1 of the present embodiment, first, a powder feeding apparatus 100 of a comparative example will be briefly described with reference to FIGS. The powder supply apparatus 100 of the comparative example has an opening 131 that is always open above the powder box 130. 8A shows a state where the powder box 130 is in the retracted position, and FIG. 8B shows a state where the powder box 130 is in the powder supply position.

  In the powder supply apparatus 100 of the comparative example, the amount of powder supplied from the storage tank 120 to the powder box 130 is adjusted by opening and closing one shutter 121 provided in the storage tank 120. For this reason, the amount of powder supplied to the powder box 130 is likely to fluctuate, and it is difficult to make the amount of powder in the powder box 130 constant during powder feeding. Therefore, the fluidity of the powder P supplied from the powder box 130 to the cavity 15 is different for each shot, and the amount of the supplied powder varies.

  Further, in the powder supply apparatus 100 of the comparative example, when the powder box 130 moves on the die 11 from the retracted position to the powder supply position, the powder P in the powder box 130 is unevenly distributed on one side in the powder box 130 due to inertial force. By putting the powder P in such a state into the cavity 15, the powder density in the cavity 15 is biased. Moreover, since the upper side of the powder box 130 is always open, the powder P in the powder box 130 may leak to the outside due to the movement of the powder box 130.

(1) As described above, the powder feeding apparatus 1 of the present embodiment supplies the powder P to the cavity 15 opened on the upper surface of the die 11 used for forming the green compact. The storage chamber shutter 32 and the control unit 50 are provided.
The powder box 31 has a storage space 310 for storing the powder P, and moves between a retracted position where the upper surface of the die 11 faces the storage space 310 and a powder supply position where the storage space 310 communicates with the cavity 15.
The storage chamber shutter 32 can be switched between a closed state in which the storage space 310 is partitioned into a first storage chamber 313 and a second storage chamber 315 and an open state in which the first storage chamber 313 and the second storage chamber 315 communicate with each other. is there. The first storage chamber 313 is arranged on the upper side in the vertical direction, and the second storage chamber 315 is arranged on the lower side in the vertical direction and has a volume larger than the volume of the cavity 15. The storage chamber shutter 32 separates the powder P in the storage space 310 into a first storage chamber 313 and a second storage chamber 315.
The control unit 50 controls the operation of the storage chamber shutter 32.

According to the above configuration, when the storage chamber shutter 32 is switched from the open state to the closed state while the powder P is stored in the storage space 310, the powder P is cut out to the second storage chamber 315 and filled with the powder P. The second storage chamber 315 can be partitioned. That is, the second storage chamber 315 is filled with the powder P having a certain volume.
In the present embodiment, the control unit 50 maintains the storage chamber shutter 32 in the closed state while the powder box 31 moves from the retracted position to the powder supply position. Accordingly, since the second storage chamber 315 is partitioned in a state where the powder P is filled, the powder P in the powder box 130 receives an inertial force while the powder box 31 moves from the retracted position to the powder feeding position. However, the powder P in the second storage chamber 315 is not biased.
Further, when the powder box 31 is located at the powder supply position, since the storage chamber shutter 32 is in a closed state, a certain amount of powder P divided into the second storage chamber 315 is supplied to the cavity 15.

  Thus, according to the powder feeder 1 of the present embodiment, it is possible to supply a certain amount of the powder P to the cavity 15 for each shot while preventing the uneven distribution of the density of the powder P in the second storage chamber 315. it can. Thereby, since the fluidity | liquidity of the powder P supplied to the cavity 15 is stabilized, the powder supply apparatus 1 can make the density distribution of the green compact after pressure molding constant, and can improve dimensional accuracy.

(2) The powder feeding apparatus 1 of the present embodiment further includes a storage tank 21, a first storage chamber shutter 22, and a second storage chamber shutter 23.
The storage tank 21 has a storage space 210 that stores the powder P, and a supply port 212 that can supply the powder P in the storage space 210 to the powder box 31 located at the retreat position.
The first storage chamber shutter 22 has a closed state that divides the storage space 210 into a first storage chamber 214 disposed on the upper side in the vertical direction and a second storage chamber 216 disposed on the lower side in the vertical direction, and the first storage chamber The open state where 214 and the second storage chamber 216 communicate with each other can be switched, and the powder P in the storage space 210 is divided into the first storage chamber 214 and the second storage chamber 216.
The second storage chamber shutter 23 blocks and communicates with the second storage chamber 216 and the supply port 212.

  According to the above configuration, when the first storage chamber shutter 22 is switched from the open state to the closed state in a state where the second storage chamber shutter 23 is in the closed state and the powder P is stored in the storage space 210, the powder P The second storage chamber 216 in a state where is satisfied is partitioned. That is, a fixed volume of powder P can be stored in the second storage chamber 216. Thereafter, when the second storage chamber shutter 23 is switched from the closed state to the open state, a certain volume of powder P is supplied from the second storage chamber 216 to the powder box 31 through the supply port 212.

  When supplying a plurality of shots continuously, the powder stored in the storage space 310 before the storage chamber shutter 32 is separated by supplying the storage space 310 each time the supply of one shot to the cavity 15 is completed. The volume of P can be made constant. Thereby, the density of the powder P cut out to the second storage chamber 315 can be stabilized for each shot, and the amount of the powder supplied to the cavity 15 can be further stabilized.

  (3) The powder feeding apparatus 1 of the present embodiment further includes a sensor 33 capable of detecting the volume of the powder P accommodated in the accommodation space 310 of the powder box 31. The controller 50 can control each operation of the first storage chamber shutter 22 and the second storage chamber shutter 23 based on the volume of the powder P detected by the sensor 33.

In particular, in this embodiment, when the sensor 33 detects that the volume of the powder P is equal to or lower than a predetermined lower limit value, the control unit 50 causes the first storage chamber to supply the powder P to the powder box 31. The shutter 22 and the second storage chamber shutter 23 are opened and closed.
According to such a configuration, the powder P that is necessary and sufficient to fill the second storage chamber 315 is reliably stored in the storage space 310 before the storage chamber shutter 32 is separated. This is suitable when a plurality of shots are supplied continuously.

(4) The green compact was molded a plurality of times using the powder feeder 1 of the present embodiment, and the thickness of the green compact was measured. The result is shown in FIG. In FIG. 9, the measurement result of the thickness of the green compact at the time of shape | molding green compact several times using the powder supply apparatus 100 of a comparative example is also shown.
As shown in FIG. 9, compared with the comparative example, in the powder feeder 1, it turned out that the dispersion | variation in the thickness of a molded object reduces about 50%.

  (5) Further, in the method for supplying powder to the cavity 15 according to the present embodiment, a powder having a volume sufficient to fill the second storage chamber 315 in the storage space 310 of the powder box 31 located at the retracted position in S101. After the supply, the storage space 310 is partitioned into a first storage chamber 313 and a second storage chamber 315 by the storage chamber shutter 32 in S102. As a result, the second storage chamber 315 is filled with the powder P. Therefore, even if the powder box 31 moves from the retracted position to the powder feeding position, the powder P in the second storage chamber 315 has an uneven density distribution. It becomes difficult. Further, since only a certain amount of powder divided into the second storage chamber 315 is supplied to the cavity 15, the fluidity of the powder P put into the cavity 15 from the second storage chamber 315 is stabilized. Accordingly, the method for supplying powder to the cavity 15 according to the present embodiment makes it possible to make the density distribution of the green compact after pressure forming constant and improve the dimensional accuracy.

  (6) In the method for supplying powder to the cavity 15 according to the present embodiment, the powder P in the second storage chamber 216 is supplied to the storage space 310 in S101, and then the second storage chamber shutter 23 is closed. Thereafter, the first storage chamber shutter 22 is opened, and the second storage chamber 216 is filled with the powder P in the first storage chamber 214. After filling the second storage chamber 216 with the powder P, the first storage chamber shutter 22 is closed and the first storage chamber 214 and the second storage chamber 216 are partitioned. Thereby, when supplying a plurality of shots continuously, the storage chamber shutter 32 is provided by supplying the powder P in the second storage chamber 216 to the storage space 310 every time supply of one shot to the cavity 15 is completed. The volume of the powder P accommodated in the accommodation space 310 can be made constant before cutting. Therefore, the density of the powder P cut out into the second storage chamber 315 can be stabilized for each shot, and the amount of the powder supplied to the cavity 15 can be further stabilized.

[Second Embodiment]
The powder feeder of 2nd Embodiment is demonstrated with reference to Fig.5 (a)-(c) and Fig.6 (a)-(c). The second embodiment is different from the first embodiment in the configuration of the second storage chamber shutter 230 and the storage chamber shutter 320.

  As shown in FIGS. 5A to 5C, the second storage chamber shutter 230 includes a plurality of plate members 231 having through holes 233 as “storage side through holes”. The plurality of plate members 231 are movable in different directions with respect to the storage tank 21.

  When the horizontal positions of the through holes 233 of the plate member 231 overlap each other in the storage space 210, the second storage chamber shutter 230 is opened. On the other hand, when the horizontal positions of the through holes 233 of the plate member 231 are different from each other, the second storage chamber shutter 230 is closed. In particular, it is preferable that the horizontal position of the through hole 233 starts to overlap from the radial center of the storage space 210.

  When the second storage chamber shutter 230 is switched from the closed state to the open state, the powder P falls from the radial center portion of the second storage chamber 216 and radially outward from the radial center portion of the storage space 310 of the powder box 31. It accumulates to spread. Thereby, the powder density in the accommodation space 310 can be made more uniform.

As shown in FIGS. 6A to 6C, the storage chamber shutter 320 includes a plurality of plate members 321 having through holes 323 as “accommodating side through holes”. The plurality of plate members 321 can move in different directions with respect to the powder box 31.
When the horizontal positions of the through holes 323 of the plate member 321 overlap each other in the storage space 310, the storage chamber shutter 320 is opened. On the other hand, when the horizontal positions of the through holes 323 of the plate member 321 are different from each other, the storage chamber shutter 320 is closed. In particular, it is preferable that the horizontal position of the through hole 323 starts to overlap from the radial center of the accommodation space 310.

  When the storage chamber shutter 320 is switched from the closed state to the open state, the powder P falls from the radial central portion of the first storage chamber 313 and accumulates while spreading from the radial central portion of the second storage chamber 315 outward in the radial direction. I will do it. Thereby, the powder density in the second storage chamber 315 can be made more uniform.

  According to such 2nd Embodiment, compared with 1st Embodiment, the powder density in the cavity 15 can be made uniform. For this reason, the quantity of the powder P supplied to the cavity 15 can be stabilized more.

  The number and shape of the plate members 231 and 321 are not particularly limited and can be determined based on the structure of the storage tank 21 or the powder box 31.

[Other Embodiments]
In the example embodiment, as shown in FIG. 7, the cavity 15 may be formed by lowering the lower punch 12 after the powder box 31 is located at the powder feeding position. When supplying the powder P to such a cavity 15, the powder density in the cavity 15 can be made more uniform.

  In another embodiment, the volume of the second storage chamber 216 may be smaller or larger than the volume of the powder P corresponding to the amount of powder for one shot. In the former case, the powder P in the second storage chamber 216 may be supplied to the powder box 31 a plurality of times after one shot of powder supply. In the latter case, the volume of the second storage chamber 216 may be configured so as to be larger than the volume corresponding to the volume of one shot and the amount of powder for one shot, for example.

In another embodiment, the sensor 33 may detect that the volume of the powder P in the accommodation space 310 is greater than or equal to a predetermined upper limit value. For example, the predetermined upper limit value may be set to a value that prevents the powder P from being excessively stored in the storage space 310. When the sensor 33 detects that the volume of the powder P is equal to or greater than a predetermined upper limit value, the control unit 50 causes the first storage chamber shutter 22 and the second storage chamber shutter to pause the next powder supply once. The opening / closing operation of 23 is stopped.
In another embodiment, a plurality of sensors 33 may be provided in the powder box 31 to detect a predetermined upper limit value and a predetermined lower limit value for the volume of the powder P in the accommodation space 310, respectively.

  In the second embodiment, the size of the through hole 233 of the second storage chamber shutter 230 may be any size as long as it fits in the storage space 210. Similarly, the size of the through hole 323 of the storage chamber shutter 320 may be any size as long as it can fit in the storage space 310.

  In the second embodiment, the second storage chamber shutter 230 has one through-hole 233. In other embodiments, the second storage chamber shutter 230 has a plurality of through-holes 233. Also good. The same applies to the through-hole 323 of the storage chamber shutter 320.

  In the above-described embodiment, after the storage chamber shutter 32 in the open state is switched to the closed state in S102, the powder box 31 is slid on the upper surface 13 of the die 11 from the retracted position to the powder supply position in S103. However, the timing at which the storage chamber shutter 32 in the open state is switched to the closed state is not limited to this. While the powder box 31 is moving from the retreat position to the powder supply position, the open storage chamber shutter 32 is switched to the closed state, and the storage space 310 is partitioned into a first storage chamber 313 and a second storage chamber 315. May be. More specifically, the first storage chamber 313 and the second storage chamber 315 may be partitioned before the second storage chamber 315 communicates with the cavity 15.

  In the above-described embodiment, in S101, the storage tank 21 supplies the powder P to the powder box 31 located at the retracted position as the “first process”, and then the second storage chamber shutter 23 as the “fourth process”. Is in a closed state. However, the “first process” and the “fourth process” may not be performed in the same step. For example, the “fourth step” may be performed in S102, S103, and S104 so that the powder can be supplied to the first storage chamber 313 of the powder box 31 as the “seventh step” in S105.

  In the above-described embodiment, in S102, the storage space 310 is partitioned into the first storage chamber 313 and the second storage chamber 315 as the “second step”, while the storage tank 21 is closed in the closed state as the “fifth step”. The one storage chamber shutter 22 is assumed to be switched to the open state. However, the “second process” and the “fifth process” may not be performed in the same step. For example, the “fifth step” may be performed in S101, S103, and S104 so that the powder can be supplied to the first storage chamber 313 of the powder box 31 as the “seventh step” in S105.

  In the above-described embodiment, when the powder box 31 moves from the retracted position to the powder feeding position as the “third process” in S103, the first storage chamber shutter 22 in the open state of the storage tank 21 is used as the “sixth process”. Suppose that it switches to the closed state. However, the “third process” and the “sixth process” may not be performed in the same step. For example, the “sixth step” may be performed in S101, S102, and S104 so that the powder can be supplied to the first storage chamber 313 of the powder box 31 as the “seventh step” in S105.

  As mentioned above, this invention is not limited to each above-mentioned embodiment, In the range which does not deviate from the meaning of invention, it can implement with a various form.

DESCRIPTION OF SYMBOLS 1 ... Powder feeding apparatus 11 ... Die 15 ... Cavity 31 ... Powder box 310 ... Storage space 313 ... 1st storage chamber 315 ... 2nd storage chamber 32, 320 ...・ Container shutter 50 ... Control unit

Claims (8)

A powder supply apparatus for supplying powder to a cavity (15) opened on an upper surface of a die (11) used for forming a green compact,
A powder box (31) having a storage space (310) for storing powder and movable between a retracted position where the upper surface of the die faces the storage space and a powder supply position where the storage space communicates with the cavity )When,
A closed state in which the storage space is partitioned into a first storage chamber (313) disposed on the upper side in the vertical direction and a second storage chamber (315) disposed on the lower side in the vertical direction and having a volume larger than the volume of the cavity; A storage chamber shutter that can switch between an open state in which the first storage chamber and the second storage chamber communicate with each other, and that can separate powder in the storage space into the first storage chamber and the second storage chamber ( 32, 320),
A control unit (50) for controlling the operation of the storage chamber shutter;
A powder supply apparatus comprising:   The said control part maintains the said storage chamber shutter in the said closed state, while the said powder box moves from the said retracted position to the said powder supply position, The powder supply apparatus of Claim 1 characterized by the above-mentioned. The storage chamber shutter (320) includes a plurality of plate members (321).
Each of the plurality of plate members has an accommodation-side through hole (323), and the horizontal position of the accommodation-side through hole can be switched between a state where they overlap each other in the accommodation space and a different state. The powder feeding apparatus according to claim 1 or 2. A storage tank (21) having a storage space (210) for storing powder, and a supply port (212) capable of supplying the powder in the storage space to the powder box located at the retracted position;
A closed state that divides the storage space into a first storage chamber (214) disposed on the upper side in the vertical direction and a second storage chamber (216) disposed on the lower side in the vertical direction; A first storage chamber shutter (22) capable of switching between an open state in communication with the second storage chamber and capable of separating powder in the storage space into the first storage chamber and the second storage chamber;
A second storage chamber shutter (23, 230) for blocking and communicating between the second storage chamber and the supply port;
The powder feeding apparatus according to any one of claims 1 to 3, further comprising: The second storage chamber shutter (230) includes a plurality of plate members (231),
Each of the plurality of plate members has a storage-side through-hole (233), and the horizontal position of the storage-side through-hole can be switched between a state where they overlap each other in the storage space and a different state. The powder feeding apparatus according to claim 4. A sensor (33) capable of detecting the volume of the powder contained in the accommodation space of the powder box;
The said control part can control each operation | movement of a said 1st storage chamber shutter and a said 2nd storage chamber shutter based on the volume of the powder detected by the said sensor. The powder feeding apparatus as described. There is an accommodation space (310) for accommodating the powder supplied to the cavity (15) opened on the upper surface of the die (11) used for compacting, and the upper surface of the die faces the accommodation space. A powder box (31) movable between a position and a powder supply position where the accommodation space communicates with the cavity;
A closed state in which the storage space is partitioned into a first storage chamber (313) disposed on the upper side in the vertical direction and a second storage chamber (315) disposed on the lower side in the vertical direction and having a volume larger than the volume of the cavity; A storage chamber shutter that can switch between an open state in which the first storage chamber and the second storage chamber communicate with each other, and that can separate powder in the storage space into the first storage chamber and the second storage chamber ( 32, 320),
A control unit (50) for controlling the operation of the storage chamber shutter;
A powder feeding method using a powder feeding device comprising:
A first step of supplying a sufficient volume of powder to fill the second storage chamber into the storage space of the powder box located at the retracted position;
A second step of partitioning the storage space into the first storage chamber and the second storage chamber by the storage chamber shutter after the first step;
A third step of supplying powder in the second storage chamber to the cavity;
Including a powdering method. A storage tank (21) having a storage space (210) for storing powder, and a supply port (212) capable of supplying the powder in the storage space to the powder box located at the retracted position;
A closed state in which the storage space is partitioned into a first storage chamber (214) disposed on the upper side in the vertical direction and a second storage chamber (216) disposed on the lower side in the vertical direction; the first storage chamber and the first storage chamber; A first storage chamber shutter (22) capable of switching between an open state communicating with the two storage chambers and capable of separating the powder in the storage space into the first storage chamber and the second storage chamber;
A second storage chamber shutter (23, 230) that shuts off and communicates with the second storage chamber and the supply port, and a powder supply method using the powder supply apparatus, further comprising:
A fourth step of closing the second storage chamber shutter after supplying the powder in the second storage chamber to the housing space in the first step;
After the fourth step, the fifth step of opening the first storage chamber shutter and filling the second storage chamber with the powder stored in the first storage chamber;
A sixth step of closing the first storage chamber shutter after the fifth step;
After the sixth step, the seventh step of opening the second storage chamber shutter and supplying the powder in the second storage chamber to the storage space located at the retracted position;
The powder supply method according to claim 7, comprising:

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