JP2006136924A - Powder-compacting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a powder-compacting apparatus capable of preventing stuffing and separation of powder, consistently feeding powder to a feeder unit and a filling unit, and reducing fluctuation of the density of a green compact. <P>SOLUTION: The powder-compacting apparatus comprises an upper hopper 12 mounted on an upper portion of a side part of a powder-compacting press, a lower hopper 52 which is mounted above a die plate 97 to feed the powder M fed from the upper hopper 12 to a storage space 71a of a shoe box 71, and a shutter plate 72 for allowing a lower end 52b of the lower hopper 52 to communicate with the storage space 71a at the retracting position of an opening part 72a of the shutter plate 72, and further comprises a pusher cylinder unit 3 to convey the fed powder M toward an upper end opening part 52c between a lower end 12b formed on the upper hopper 12 and an upper end opening part 52c formed on the lower hopper 52. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a powder molding apparatus.

  The green compact used for the production of sintered parts is premixed with powders such as carbon, Cu-based metal, and Fe-based metal, and the mixture is supplied to the filling part of the press die and pressure-molded in the apparatus. As a mechanism for filling powder into a powder molding apparatus, a mechanism including a die in which a filling portion is formed and a feeder that supplies powder to the filling portion is known (for example, Patent Document 1). reference).

The powder molding apparatus described in Patent Document 1 includes a hopper attached above a side of a powder press, a die that forms a filling portion between an upper punch, a lower punch, and a core rod, and is flush with the die. A die plate provided, and a feeder that is reciprocally moved in the horizontal direction on the die and the upper surface of the die plate are provided.
An opening is formed in the lower surface of the feeder, and powder is supplied from the hopper to the powder storage space of the feeder via a hose.
Japanese Patent Laid-Open No. 2004-243401

However, in the powder molding apparatus described in Patent Document 1, as the feeder reciprocates, the feeder side portion of the hose provided between the hopper and the feeder is also moved in the horizontal direction. The flow of water is not stable and the supply amount tends to vary.
Further, since vibration is applied to the powder staying inside the hose, there is a problem that the components of the powder having different specific gravity are separated inside the supply pipe.

  In this case, if the distance between the top and bottom of the hopper and the feeder is increased, the powder pressure inside the hose increases, so the variation tends to increase. Conversely, if the distance between the top and bottom of the hopper and the feeder is shortened, the feeder fills. When it is in the vicinity of the part, the hose becomes almost horizontal, and the powder becomes clogged in the hose and hardly flows.

  Furthermore, even if a screw-type feeder or a vibration feeder that does not use a hose is used, vibration is still applied to the powder, so that it is inevitable that the components of the powder are separated inside the supply pipe.

In view of the above problems, the present invention is to provide a powder molding apparatus capable of preventing powder clogging and separation.
Another object of the present invention is to provide a powder molding apparatus that can stably supply powder to the feeder part and the filling part and reduce the density variation of the green compact.

  In order to solve the above-described problems and achieve such an object, the powder molding apparatus according to claim 1 includes a die in which a powder filling portion is formed, and a powder containing space formed therein. An opening is formed in the lower part, and the opening is disposed in contact with the upper surface of the die so as to be capable of moving forward and backward, and is provided with a feeder part that supplies powder to the filling part. A first hopper for storing powder attached to the upper side of the press and a die plate of the powder forming press, and temporarily storing the powder supplied from the first hopper, A second hopper for supplying the storage space, and an opening / closing means for allowing the powder outlet formed in the second hopper to communicate with the storage space of the feeder portion at the retracted position of the opening. And the powder supplied from the powder outlet portion of the first hopper between the powder outlet portion formed in the first hopper and the powder inlet portion formed in the second hopper, A lateral conveyance mechanism for conveying the powder toward the powder inlet of the second hopper is provided.

According to the first aspect of the present invention, since the powder conveyance in the horizontal direction between the first hopper and the second hopper is performed by the lateral conveyance mechanism provided between the hoppers, the powder is clogged. Is stably conveyed from the first hopper to the second hopper.
In addition, the lateral transport mechanism includes a powder feeding tray to which powder is supplied from the powder outlet of the first hopper, and the powder fed from the second hopper is moved forward and backward on the powder feeding tray. And a plate member that is conveyed to the inlet portion, and the powder is stably conveyed from the first hopper to the second hopper without being subjected to vibration (claim 2).
Furthermore, the pressure of the powder stored in the second hopper is controlled by providing a transport amount control unit that drives the lateral transport mechanism based on the detection result of at least one sensor that detects the amount of powder stored in the second hopper. It is maintained appropriately and the powder is stably supplied to the feeder part and the filling part (Claim 3).

  According to the powder molding apparatus according to the present invention, powder clogging and separation can be prevented, and the powder can be stably supplied to the feeder part and the filling part, so that the density variation of the green compact can be reduced.

1 to 4 show an embodiment of a powder molding apparatus according to the present invention, FIG. 1 is an overall view of the powder molding apparatus, and FIGS. 2 to 4 are schematic configurations of respective parts of the powder molding apparatus. Each is shown.
In the following description, a direction in which a shoe box 71 described later approaches the filling portion C will be described as a forward direction, and a direction away from the filling portion C will be described as a backward direction.

  A powder molding apparatus 1 shown in FIG. 1 includes an upper hopper 2 in which raw material powder M is stored, a pusher cylinder unit (lateral transport mechanism) 3 that transports the powder M supplied from the upper hopper 2 in the lateral direction, and the pusher. Lower hopper part 4 in which powder M conveyed from cylinder part 3 is temporarily stored, feeder part 5 for filling powder C supplied from this lower hopper part into filling part C, and filled powder M are pressure-molded It is comprised from the metal mold | die part 6 made.

FIG. 2 shows a configuration of the upper hopper portion 2, and the upper hopper portion 2 is not movable in the horizontal direction above the side portion of the powder molding press P by the bracket 11, and is an upper hopper (first hopper) 12. It is set as the structure attached.
The upper hopper 12 includes a large capacity powder storage space 12a, and a hose 15 having flexibility via a ball valve 14 whose lower end (powder outlet) 12b can be opened and closed by a handle 13. It is connected.
Further, the powder storage space 12 a of the upper hopper 12 is closed by a lid 16 so that the powder is not scattered outside the upper hopper 12.

The upper end of the hose 15 is attached to the lower end portion 12b of the upper hopper 12, and the lower end is attached to the upper end of an opening of a joint 36, which will be described later, arranged substantially vertically downward.
The level sensor 17 detects the amount of powder in the powder storage space 12a as needed.

3A and 3B show the configuration of the pusher cylinder part 3, in which FIG. 3A shows a plan view and FIG. 3B shows a front view.
The pusher cylinder portion 3 includes a pair of brackets 31, 31 to which a powder feeding tray 32 is horizontally attached to a powder molding press P, and an upper plate 33 covering the tray, and a plate member 34 fixed to the upper plate 33. Is arranged so as to be movable on the powder feeding tray 32.

In FIG. 3, the powder feed tray 32 is formed in a bowl shape to define an internal space 32a, and a powder outlet 32c projects downward from the left end of the bottom surface 32b of the internal space 32a in FIG. Is formed.
Further, an upper plate 33 is provided to face the bottom surface 32b so as to cover the internal space 32a, and a slot-like notch 33a is formed at the left end portion of the upper plate 33 in FIG. Yes.
A pair of guide walls 33c and 33c are formed upright from the upper surface 33b of the upper plate 33, and in the vicinity of the notch 33a of the bottom surface 33d of the upper plate 33, the plate member 34 is provided in each of the internal spaces 32a. It is slidably attached to the wall.

On the upper surface 33b of the upper plate 33, a spring receiver 35 having a through hole 35a is placed.
The lower surface 35b of the spring receiver 35 can be slidably contacted with the upper surface 33b of the upper plate 33, and the side surface of the spring receiver 35 is engaged with the guide walls 33c and 33c.
An open lower end 36a of a substantially cylindrical joint 36 is fitted into the through hole 35a.
The lower end of the hose 15 from the upper hopper 12 described above is attached to the upper end of the opening of the joint 36, and a flange portion 36 b is formed at the center in the longitudinal direction of the joint 36.
The lower surface 35 b of the spring receiver 35 is urged against the upper surface 33 b of the upper plate 33 by the spring 37 held between the flange portion 36 b and the spring receiver 35.

A driving rod 38 is attached to the center of the plate member 34 so as to extend in the longitudinal direction of the internal space 32a, and the driving rod 38 is connected to driving means (not shown).
The drive rod 38 causes the upper plate 33 and the plate member 34 to have the notch 33a opposed to the opening lower end 36a of the joint 36 from the advance position (see FIG. 3) where the plate member 34 is moved to the vicinity of the powder outlet portion 32c. It is possible to reciprocate between the retreat position.
Further, a flexible hose 39 is attached to the tip of the powder outlet portion 32c vertically downward, and opens toward a powder storage space 52a of the lower hopper 52 described later.

4 shows the configuration of the lower hopper part 4, the feeder part 5 and the mold part 6. FIG. 4 (a) shows a plan view and FIG. 4 (b) shows a front view.
The lower hopper portion 4 has a structure in which a lower hopper 52 is mounted on a die plate 97, which will be described later, by a pair of brackets 51 and 51 so that the lower hopper 52 cannot move in the horizontal direction. Has been.
Further, the lower hopper 4 is arranged in a notch 91a of an upper punch plate 91 described later, and is configured not to interfere with the upper punch plate 91 during vertical movement.

The lower hopper (second hopper) 52 includes a powder storage space 52a having a relatively small capacity, and a lower end portion (powder outlet portion) 52b of the lower hopper 52 is attached to an upper end of an opening of a joint 74 described later. ing.
Further, the lower end portion of the hose 39 from the pusher cylinder portion 3 described above is guided from the upper end opening portion 52c of the lower hopper 52 to the powder containing space 52a.
Further, an upper level sensor 53 and a lower level sensor 54 are inserted from the outside of the lower hopper 52 toward the powder storage space 52a with an appropriate interval, and the amount of powder in the powder storage space 52 is reduced. It is detected from time to time.

Next, the feeder unit 5 will be described.
The feeder unit 5 is placed on an upper surface 96a of a die 96, which will be described later, and an upper surface 97a of a die plate 97, which will be described later.
In the shoe box 71 having a box shape, an accommodation space 71a and a lower surface opening 71b are formed.
The lower surface opening 71b can be slidably contacted with the upper surface 96a of the die 96 and the upper surface 97a of the die plate 97.

A shutter plate (opening / closing means) 72 is attached to the upper surface 71c of the shoe box 71 so as to cover the accommodation space 71a.
In the shutter plate 72, an opening 72a is formed so as to face the accommodation space 71a of the shoe box 71, and a pair of guide walls 72c and 72c are formed upright from an upper surface 72b of the shutter plate 72. .

A spring receiver 73 having a through hole 73 a is placed on the upper surface 72 b of the shutter plate 72.
The lower surface 73b of the spring receiver 73 can be slidably contacted with the upper surface 72b of the shutter plate 72, and the side surface of the spring receiver 73 is engaged with the guide walls 72c and 72c.
An open lower end 74a of a substantially cylindrical joint 74 is fitted into the through hole 73a.
The lower end portion 52b of the lower hopper 52 described above is attached to the upper end opening portion of the joint 74, and a flange portion 74b is formed in the longitudinal center portion of the joint 74.
The lower surface 73 b of the spring receiver 73 is biased against the upper surface 72 b of the shutter plate 72 by a spring 75 held between the flange portion 74 b and the spring receiver 73.

The side surfaces of the shoe box 71 are engaged with the ends 76a and 76a of arms 76 and 76 that extend in the longitudinal direction of the accommodation space 71a. The opposite ends of the arms 76 and 76 are not shown. The drive means is pivotally supported so as to be rotatable.
With these arms 76, 76, the shoe box 71 and the shutter plate 72 move up and down in conjunction with the movement of the die 96 and the die plate 97, while the lower surface opening portion 71b of the shoe box 71 faces the filling portion C. From the position (see FIG. 4), the through hole 73a of the shutter plate 72 can reciprocate between a retracted position facing the opening lower end 74a of the joint 74.

The mold part 6 will be described with reference to FIGS. 1 and 4B.
The mold portion 6 includes an upper punch plate 91 in which a notch 91a is formed, an upper punch 92 supported and fixed to the upper punch plate 91 so as to be movable in the vertical direction, and below the upper punch 92. A lower punch 94 supported and fixed to the lower punch plate 93, and a core rod 95 that penetrates the center of the lower punch 94 and is provided so as to be relatively movable in the vertical direction. The upper punch 92, the lower punch 94, and the core rod A die 96 that forms a cylindrical filling portion C between the die 96 and a die plate 97 that holds the die 96 and is flush with the die 96.
Further, a guide rod 98 slidably penetrating the lower punch plate 93 is extended on the lower surface of the die plate 97, and a lower end of the guide rod 98 is a yoke that can be moved up and down by a driving device (not shown). It is fixed to the plate 99.

Next, the operation of the powder molding apparatus 1 will be described.
In the upper hopper portion 2, the ball valve 14 is normally in an “open” state, and is retracted to a retracted position where the notch 33 a of the upper plate 33 of the pusher cylinder portion 3 faces the open lower end 36 a of the joint 36. If it is, the powder M in the upper hopper 12 is always supplied into the internal space 32 a of the powder feeding tray 32.
Further, the remaining amount of the powder M in the powder storage space 12a of the upper hopper 12 is monitored at any time by the level sensor 17, and when the remaining amount decreases, the lid 16 is removed, and the powder M is appropriately placed in the storage space 12a. Added.

In the pusher cylinder portion 3, when the powder M is supplied from the upper hopper 12, the plate member 34 to which the upper plate 33 is attached is advanced and retracted by the drive rod 38.
At this time, the guide walls 33 c and 33 c of the upper plate 33 are engaged with the side surfaces of the spring receiver 35, and the upper surface 33 b of the upper plate 33 is in sliding contact with the lower surface 35 b of the spring receiver 35.
Further, since the spring receiver 35 is urged to the upper surface 33b of the upper plate 33 by the spring 75, the powder M does not scatter to the outside from the lower surface 35b.

When the plate member 34 is retracted to the retracted position where the notch 33a of the upper plate 33 faces the opening lower end 36a of the joint 36, the plate member 34 is stored in the upper hopper 12 via the ball valve 14, the hose 15 and the joint 36. The powder M is supplied into the internal space 32a of the powder feeding tray 32 from the opening lower end 36a.
Then, the supplied powder M is conveyed to the powder outlet portion 32c by the plate member 34 being advanced by the drive rod 38, and into the powder accommodating space 52a from the upper opening surface of the lower hopper 52 via the hose 39. To be replenished.
At this time, as the plate member 34 advances, the upper plate 33 closes the open lower end 36 a of the joint 36.

In the lower hopper 4, the amount of powder in the powder storage space 52 a of the lower hopper 52 is determined based on the conveyance amount (not shown) that determines whether or not the pusher cylinder 3 needs to be operated in response to signals from the upper level sensor 53 and the lower level sensor 54. When the amount of powder falls below the lower limit of the allowable level, which is monitored at any time by the control unit, the pusher cylinder unit 3 is operated as described above, and the powder M stored in the upper hopper unit 2 is moved to the pusher cylinder. The lower hopper 52 is replenished via the part 3.
Further, when the amount of powder reaches the upper limit of the allowable level, the operation of the pusher cylinder unit 3 is stopped, and the replenishment of the powder M is also stopped.
The allowable level of the amount of powder in the lower hopper 52 is determined so that the powder M is supplied to the accommodation space 71a of the shoe box 71 at a predetermined powder pressure so that the density variation of the green compact can be suppressed as much as possible. Is considered.

In the feeder part 5, when the shoe box 71 to which the shutter plate 72 is attached is retracted by the arms 76, 76 to a position where the opening 72a of the shutter plate 72 and the opening lower end 74a of the joint 74 are communicated with each other. The powder M accommodated in the lower hopper 52 is supplied into the accommodating space 71 a from the opening lower end 74 a of the joint 74.
At this time, the guide walls 72 c and 72 c of the shutter plate 72 are engaged with the side surfaces of the spring receiver 73, and the upper surface 72 b of the shutter plate 72 is in sliding contact with the lower surface 73 b of the spring receiver 73.
Further, since the spring receiver 73 is urged to the upper surface 72b of the shutter plate 72 by the spring 75, the powder M is not scattered outside from the lower surface 73b.

The shoe box 71 is advanced by the arms 76, 76 to a position where the lower surface opening 71b of the shoe box 71 faces the filling portion C, and the powder M in the accommodation space 71a is filled into the filling portion C.
As the shoe box 71 moves forward, the upper surface 71a of the shutter plate 71 closes the opening lower end 74a of the joint 74.
Next, after the shoe box 71 is retracted, the upper punch 92 is lowered and the raw material powder M is compressed in the filling portion C, whereby a green compact (not shown) is formed.
Thereafter, the upper punch 92 is raised and the lower punch plate 93 and the lower punch 94 are raised, whereby the green compact is pushed up onto the die plate 97 by the lower punch 94.
Such a process is repeated so that the green compacts are sequentially formed.

In the present embodiment, the upper hopper portion 2 having a large capacity accommodation space 12a is attached to the upper side of the powder molding apparatus main body so as not to move horizontally, and the lower hopper portion having a relatively small capacity accommodation space 52a. 4 is mounted above the die plate 97 so as to be immovable in the horizontal direction, and the pusher cylinder portion 3 is provided as a lateral transfer mechanism between the first hopper 12 and the second hopper 52, so that the first hopper The horizontal relative positional relationship between the hopper 12 and the second hopper 52 can be kept constant.
Further, in the pusher cylinder portion 3, the powder M supplied on the powder feeding tray 32 is horizontally extruded by the plate member 34, and extra vibration is added to the powder M in which a plurality of components having different specific gravities are mixed. Therefore, it is possible to prevent the components of the powder M from being separated inside the pusher cylinder portion 3.
In the present embodiment, the hose 15 is provided between the upper hopper portion 2 and the pusher cylinder portion 3 and the hose 39 is provided between the pusher cylinder portion 3 and the lower hopper portion 4. And the hose 39 do not move in the horizontal direction and can be provided substantially vertically downward, so that it is necessary to dispose the hose 15 obliquely extending from the first hopper 12 toward the second hopper 52. Absent.
Therefore, the powder is not clogged inside the hose 15 or the hose 39 and does not flow easily, and the powder M is not subjected to excessive vibration. Can be prevented from being separated inside.

In the present embodiment, the lengths of the hose 15 and the hose 39 can be made extremely short, so that an increase in the powder pressure inside the hose 15 and the hose 39 can be prevented, and filling from the feeder section 5 is possible. It becomes possible to maintain the pressure of the powder M supplied to the part C appropriately, and to reduce the density variation of the green compact.
Further, in the present embodiment, by forming the notch portion 91 a in the upper punch plate 91, even if the pusher cylinder portion 3 and the lower hopper portion 4 move up and down in conjunction with the die plate 97, they are There is no interference with the upper punch plate 91.
Further, since the operation of the pusher cylinder unit 3 is controlled by the carry amount control unit at any time in response to signals from the upper level sensor 53 and the lower level sensor 54, the powder M stored in the first hopper 12 is The second hopper can be stably supplied.

Further, in the present embodiment, the feeder part 5 is provided between the second hopper 52 and the filling part C, and the powder M is conveyed by the shoe box 71, so that the powder M having a high specific gravity is accommodated. It is not necessary to move the second hopper 52 itself forward and backward, and the configuration of the entire powder molding apparatus can be simplified.
Further, since it is not necessary to dispose the hose obliquely from the second hopper 52 toward the shoe box 71, the above-described inconvenience can be prevented more effectively.

1 is an overall view of a powder molding apparatus according to an embodiment of the present invention. It is a figure which shows the structure of the upper hopper part of the shaping | molding apparatus. The structure of the pusher cylinder part (lateral conveyance mechanism) of the shaping | molding apparatus is shown, (a) is a top view, (b) is a front view. The structure of the lower hopper part of the molding apparatus, a feeder part, and a metal mold | die part is shown, (a) is a top view, (b) is a front view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Powder shaping | molding apparatus 2 Upper hopper part 3 Pusher cylinder part (horizontal conveyance mechanism) 4 Lower hopper part 5 Feeder part 6 Mold part 12 Upper hopper (first hopper) 32 Powder feeding tray 33 Upper plate 34 Plate member 36 Joint 38 Drive rod 52 Lower hopper (second hopper) 53 Upper level sensor 54 Lower level sensor 71 Shoe box 72 Shutter plate (opening / closing means) 74 Joint 76 Arm 91 Upper punch plate 92 Upper punch 96 Die 97 Die plate M Powder

Claims (3)

A die formed with a powder filling portion;
A feeder for supplying powder to the filling portion by forming a powder containing space inside and forming an opening in the lower portion, and the opening is in contact with the upper surface of the die so as to be capable of moving forward and backward. A powder molding apparatus comprising:
A first hopper for storing powder attached above the side of the powder forming press;
A second hopper attached above the die plate of the powder molding press, temporarily storing the powder supplied from the first hopper, and supplying the powder to the accommodation space of the feeder part;
In the retracted position of the opening, provided with an opening / closing means for communicating the powder outlet formed in the second hopper with the accommodation space of the feeder,
The powder supplied from the powder outlet portion of the first hopper is placed between the powder outlet portion formed in the first hopper and the powder inlet portion formed in the second hopper. A powder molding apparatus comprising a lateral conveying mechanism for conveying toward a powder inlet of the hopper. The lateral conveyance mechanism includes a powder feeding tray to which powder is supplied from a powder outlet portion of the first hopper,
The plate member which conveys the supplied powder to the powder inlet portion of the second hopper by moving forward and backward on the powder feeding tray. Powder molding equipment. The at least one sensor for detecting the amount of powder stored in the second hopper, and a transport amount control unit for driving the lateral transport mechanism based on a detection result of the sensor. The powder molding apparatus according to 1 or 2.

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