JP6015495B2 - Powder molding equipment - Google Patents

Description

  The present invention relates to a powder molding apparatus that press-molds metal powder or the like.

2. Description of the Related Art Conventionally, a powder molding apparatus that press-molds a powder material put into a mold cavity composed of a die, a lower punch, and the like between an upper punch attached to the apparatus and a lower punch of the mold is known. ing.
For example, the powder molding apparatus disclosed in Patent Document 1 includes a die set and a punch set group including a plurality of punch sets as a mold functional unit. The die set includes a die plate and a connecting rod, and the punch set includes a punch plate and a connecting rod. In addition, as a drive function unit, a hydraulic cylinder group corresponding to each of the plurality of punch sets is provided. This powder molding apparatus can form a multi-stage molded product by forming the punch in multiple stages.

Japanese Patent Laid-Open No. 2005-29662

  In the device of Patent Document 1, the hydraulic cylinder group is configured so that multiple cylindrical cylinders surround the central cylinder, thereby reducing the size of the device in the height direction. However, since the mold function unit and the drive function unit are configured independently and the mold function unit is arranged so as to be stacked on the upper part of the drive function unit, the physique of the apparatus is still not sufficiently reduced in size. .

  Here, a comparison of terms between the present application and Patent Document 1 will be mentioned. In this application, the term “main punch” and the other “core” are used in the present application as corresponding to “plural punches” of Patent Document 1. This is derived from the difference that, in Patent Document 1, a concentric staircase-shaped molded product is a representative embodiment, whereas in the present application, a plate-shaped molded product having a plurality of through holes is a representative embodiment. . For example, the “core” in the representative embodiment of the present application is a member for removing a portion corresponding to the through hole from the cavity. However, there is no essential difference between the “lower punch and core” of the present application and the “plurality of punches” of Patent Document 1. Therefore, it is of course possible to mold the concentric stepped molded product described in Patent Document 1 using the “lower punch and core” of the present application.

  The present invention has been made in view of the above-described problems. An object of the present invention is to provide a powder molding apparatus having a mold configuration that includes at least one core in addition to a die and a lower punch. It is to provide.

The present invention relates to a powder molding apparatus that press-molds a powder material filled in a cavity between a lower punch and an upper punch provided to face the lower punch. The cavity is defined by a die in which a mold hole is formed, a lower punch inserted in the mold hole, and a plurality of cores provided separately from the lower punch inside the mold hole.
The powder molding apparatus includes a base plate, a die driving unit capable of driving the die plate supporting the die up and down relative to the base plate, and an upper punch driving unit capable of driving the upper punch plate supporting the upper punch up and down relative to the base plate. And a lower punch unit. Lower punch unit is mounted on the base plate, the lower punch, a plurality of cores, and the core actuator capable of relatively moving a plurality of cores with respect to the lower punch that are assembled together. Here, the core actuator is, for example, a hydraulic cylinder.
The plurality of cores includes a center core provided on the central axis of the lower punch, and a plurality of side cores provided along the circumferential direction outside the center core.
The plurality of core actuators are coupled to a piston that can slide in the cylinder chamber, and a core plate that fixes a flange portion whose base end is coupled to the piston and whose distal end is an end opposite to the core cavity. Includes piston rod.
In the height direction of the lower punch unit, the piston of the core actuator that drives the side core is disposed between the piston of the core actuator that drives the center core and the flange portion of the center core.

  In the lower punch unit of the present invention, the lower punch and the core as the mold function part and the core actuator as the drive function part are not independently provided, but are integrally assembled. Therefore, the physique of the powder molding apparatus can be made smaller than the prior art in which the mold function unit is arranged so as to be stacked on top of the drive function unit.

  The powder molding apparatus of the present invention can be used as a general-purpose machine by sharing the apparatus main body and replacing the lower punch unit or the like for each molded product to be applied. Since the main feature of the technical features of the present invention is the configuration of the lower punch unit, the act of producing, transferring, etc. the lower punch unit is the act of producing, transferring, etc., the items used only for the powder molding apparatus of the present invention. It seems to be applicable. Here, “used only” means that there is no other economical, commercial or practical use other than the use in the powder molding apparatus of the present invention.

1 is an overall schematic view of a powder molding apparatus according to an embodiment of the present invention. It is sectional drawing of the lower punch unit of the powder shaping | molding apparatus by one Embodiment of this invention. It is (a) top view and (b) sectional drawing of the principal part of a lower punch unit. It is a schematic diagram of the filling preparation process of the powder shaping | molding apparatus by one Embodiment of this invention. It is a schematic diagram of a filling process same as the above. It is a schematic diagram of a pressurization compression process same as the above. It is a schematic diagram of the same extraction process. It is a schematic diagram of the extraction process same as the above. (A), (b): It is a schematic diagram of the molded article shape | molded by the powder shaping | molding apparatus of one Embodiment of this invention. (C), (d), (e): It is a schematic diagram of the molded article shape | molded by the powder shaping | molding apparatus of other embodiment of this invention.

Hereinafter, a powder molding apparatus according to an embodiment of the present invention will be described with reference to the drawings.
(One embodiment)
A powder molding apparatus according to an embodiment of the present invention is an apparatus that compresses and compresses a powder material such as metal as a pre-process of a sintering method. As shown in FIG. 1, the powder molding apparatus 100 includes a base plate 11, an upper ram 12, a guide post 13, a die drive unit 70, an upper punch drive unit 80, a lower punch unit 20, and other support tables (not shown), a control panel, and the like. It is a vertical machine equipped.
When FIG. 1 is a front view of the apparatus, the side view is substantially the same, and thus the illustration is omitted. In addition, the members illustrated on the central axis O in FIG. 1 are arranged coaxially in principle.

  The base plate 11 and the upper ram 12 are rectangular plates, and support the lower and upper portions of the four guide posts 13 at square corners. The die plate 17 and the upper punch plate 18 can be moved up and down along the guide post 13 by a slide guide 19 provided at a position corresponding to the guide post 13. The die plate 17 supports the die 5 in which the mold cavity 51 is formed. The upper punch plate 18 supports the upper punch 6 that faces the lower punch 2.

  The die driving unit 70 can drive the die plate 17 up and down with respect to the base plate 11 by the operation of the lower cylinder 71 connected to the die plate 17 and the tie rod 72. Further, the upper punch driving unit 80 can drive the upper punch plate 18 up and down with respect to the base plate 11 by the operation of the upper cylinder 81 connected to the upper punch plate 18 by the tie rod 72. In this embodiment, hydraulic cylinders are used as the lower cylinder 71 and the upper cylinder 81.

The lower punch unit 20 is mounted on the base plate 11, and the lower punch 2, the side core 3, the center core 4, the side core cylinder 37, the center core cylinder 47, and the like are assembled together.
The lower punch 2 is inserted into the mold hole 51 of the die 5. The side core 3 and the center core 4 are provided separately from the lower punch 2 inside the contour of the lower punch 2 at the end surfaces. That is, the lower punch 2 is provided inside the mold cavity 51 with the lower punch 2 inserted in the mold cavity 51.
The side core cylinder 37 and the center core cylinder 47 correspond to a “core actuator” recited in the claims, and move the side core 3 and the center core 4 relative to the lower punch 2, respectively. In this embodiment, a hydraulic cylinder is used.

Next, a detailed configuration of the lower punch unit 20 will be described with reference to FIG.
A center core cylinder block 471 is fixed on the base plate 11 by a fixing member 48. On the center core cylinder block 471, the side core cylinder block 371, the pressure receiving shaft 27, the lower punch plate 26, and the lower punch presser 25 are stacked in order and fixed. The lower punch presser 25 and the lower punch plate 26 are fixed by sandwiching the flange portion of the lower punch 2. Therefore, in this embodiment, the lower punch 2 does not move.

A piston 473 coupled with a piston rod 474 is slidably accommodated in a cylinder chamber 472 formed in the center core cylinder block 471, and the center core cylinder 47 is configured by these. The center core cylinder 47 raises and lowers the piston rod 474 by supplying hydraulic pressure to the cylinder chamber 472 from a hydraulic supply path (not shown).
A center core presser 45 and a center core plate 46 that are fixed with a flange portion of the center core 4 interposed therebetween are coupled to the tip of the piston rod 474. Accordingly, the center core 4 can be driven up and down with respect to the lower punch 2 by the operation of the center core cylinder 47.

The side core cylinder block 371 cylinder chamber 372 formed in which a piston 373 which piston rod 374 is attached is slidably housed, rhinoceros DoCoMo Ashirinda 37 is constituted by these. The side core cylinder 37 raises and lowers the piston rod 374 by supplying hydraulic pressure to the cylinder chamber 372 from a hydraulic supply path (not shown).
A side core presser 35 and a side core plate 36 that are fixed with a flange portion of the side core 3 interposed therebetween are coupled to the tip of the piston rod 374. Thereby, the side core 3 can be driven up and down with respect to the lower punch 2 by the operation of the side core cylinder 37.

Further, between the lower punch plate 26 and the side core cylinder 37 fixed to each other, a side core presser 35 and a side core plate 36, and a guide pin 49 penetrating the center core presser 45 and the center core plate 46 are provided. Yes. Thereby, the positional accuracy during operation of the center core 4 and the side core 3 is ensured, and tilting and twisting are prevented.
A plurality of pressure receiving shafts 27, guide pins 49, and the like are arranged in consideration of balance including portions other than the cross section shown in FIG.

  As described above, the lower punch unit 20 includes the lower punch 2, the side core 3, and the center core 4 as mold functions, and the side core cylinder as a drive function that moves the side core 3 and center core 4 relative to the lower punch 2. 37 and the center core cylinder 47 are laminated and assembled integrally within a certain range in a plan view.

The die 5 is attached to the die plate 17 by fitting the outer wall 53 into the hole 171 of the die plate 17 and pressing the flange portion 56 with the die presser 57. The outer wall 21 of the lower punch 2 is fitted into the inner wall 52 of the mold cavity 51 formed at the center of the die 5. At the initial position of the apparatus, the height of the end face 54 of the die 5 matches the height of the end face 24 of the lower punch 2. The concave portion 55 of the die 5 accommodates the lower punch presser 25 and the lower punch plate 26.
The die 5 is not included in the lower punch unit 20 itself defined as “mounted on the base plate 11”. However, when the lower punch unit 20 is replaced, when the outer diameter or fitting length of the lower punch 2 changes, the die 5 is replaced with the lower punch unit 20 as a set.

A more detailed configuration of the upper portion of the lower punch 2 is shown in FIG. In the lower punch 2, the outer wall 21 is fitted in the inner wall 52 of the die hole 51 of the die 5. The center core 4 is provided on the central axis of the lower punch 2, and the outer wall 41 is fitted in a center core fitting hole 22 formed on the central axis of the lower punch 2. The side core 3 is provided at eight locations along the circumferential direction on the outside of the center core 4, and the outer wall 31 is fitted in a side core fitting hole 23 formed outside the center core fitting hole 22 of the lower punch 2. In the present embodiment, the side cores 3 are arranged at regular intervals in the circumferential direction, but the side cores 3 may be arranged at irregular intervals.
At the initial position of the apparatus, the heights of the end surface 32 of the side core 3 and the end surface 42 of the center core 4 coincide with the heights of the end surface 24 of the lower punch 2 and the end surface 54 of the die 5. This height position corresponds to the lower limit position DL of the end face 54 of the die 5 as will be described later.

The powder molding apparatus 100 having the above configuration forms a disk-shaped molded product P1 shown in FIGS. 9 (a) and 9 (b). The outer diameter of the molded product P1 corresponds to the outer diameter of the lower punch 2. The center through hole Hc is formed by the center core 4, and the eight side through holes Hs are formed by the side core 3. A mold for molding and extracting the molded product P1 having these through holes Hc and Hs needs to be provided with a center core 4 and a side core 3 that can move relative to the lower punch 2.
This molded product P1 is used as a member of an electromagnetic actuator, for example. For example, the center through hole Hc is used as a shaft insertion hole, and the side through hole Hs is used as a mounting bolt insertion hole.

Next, the powder molding process by the powder molding apparatus 100 will be described with reference to FIGS. 4 to 8, the molded product P <b> 1 is molded from the powder material M mainly by the relative movement of the lower punch 2, the side core 3, the center core 4, the die 5 and the upper punch 6 of the lower punch unit 20. Shows the process up to. In this embodiment, the lower punch 2 does not move among these members, and the side core 3, the center core 4, the die 5, and the upper punch 6 move along a common central axis O. In the figure, the up arrow is indicated by a block arrow with the letters “UP” and the down arrow with “DN”. Since the configuration of the cylinder that moves each member is as described above, the description thereof is omitted here.
In addition, the lower limit position of each of the end faces 24, 32, 42, 54 of the lower punch 2, the side core 3, the center core 4 and the die 5 in the lower punch unit 20 is denoted by DL, and the upper limit position is denoted by DH.

<Filling preparation process >
As shown in FIG. 4, from the initial position shown in FIG. 3B, the end face 54 of the die 5 first rises to the upper limit position DH. Then, the powder material M is put into a temporary cavity C ′ defined by the inner wall 52 of the die 5 and the end faces 24, 32, 42 of the lower punch 2, the side core 3, and the center core 4 as a preparation for filling.

<Filling process>
Subsequently, as shown in FIG. 5, the end surface 32 of the side core 3 and the end surface 42 of the center core 4 rise to the upper limit position DH and project from the end surface 24 of the lower punch 2. In this state, a space defined by the inner wall 52 of the die 5, the end face 24 of the lower punch 2, the side core 3, and the outer walls 31 and 41 of the center core 4 becomes a true cavity C. In this example, the volume of the cavity C is smaller than the temporary cavity C ′ by a volume corresponding to the protruding portion of the side core 3 and the center core 4. Accordingly, the upper surface of the charged powder material M is lifted. In FIG. 5, for convenience, the upper surface of the powder material M is illustrated so as to coincide with the upper limit position DH. However, in an actual process, the upper surface of the powder material M overflowing from the cavity C may be “ground”. is there. Thus, the powder material M is filled in the cavity C.

<Pressure compression process>
Next, as shown in FIG. 6, the upper punch 6 is lowered. Then, the outer wall 61 of the upper punch 6 is in the mold hole inner wall 52 of the die 5, the center core fitting hole 62 of the upper punch 6 is in the outer wall 41 of the center core 4, and the side core fitting hole 63 of the upper punch 6 is in the outer wall 31 of the side core 3. Are fitted simultaneously. In this state, the upper punch 6 is further lowered to a predetermined position and maintained at a predetermined temperature and pressure for a predetermined time, whereby the powder material M is compressed by pressure and cured to become a molded product P1.

<Extraction process>
Thereafter, as shown in FIG. 7, the upper punch 6 is raised to the original position, and the side surfaces 3, the center core 4 and the end face 42 of the die 5 are lowered to the lower limit position DL. Thereby, the molded product P1 is extracted from the lower punch unit 20.
<Removal process>
Finally, as shown in FIG. 8, the molded product P1 is taken out by a take-out means (not shown).

  As described above, the powder molding apparatus 100 according to the present embodiment employs a mold configuration including the side core 3 and the center core 4 in addition to the die 5 and the lower punch 2. Then, the lower punch 2, the side core 3, the center core 4, and the lower punch 2 and the die 5 can be relatively moved. Therefore, the molded product having the through holes Hs and Hc can be appropriately extracted as in the molded product P1 of the present embodiment.

  In an apparatus having such a mold configuration, a plurality of drive function units such as the side core cylinder 37 and the center core cylinder 47 are required in addition to the lower cylinder 71 that drives the die 5. Therefore, the arrangement of the mold function unit and the drive function unit is an important factor that determines the physique of the apparatus. In that respect, the powder molding apparatus 100 of the present embodiment has a conventional punching unit 20 in which the mold functional part and the drive functional part are laminated within a certain range in plan view and are integrally assembled. On the other hand, the physique of the apparatus can be reduced in size.

  When the powder molding apparatus 100 according to the present embodiment is used as a general-purpose machine for molding various molded products, the lower punch unit 20 and the upper punch 6 and, if necessary, the die 5 are provided for each molded product to be applied. Replace it. At this time, the strokes of the lower cylinder 71 and the upper cylinder 81 of the apparatus main body can be made constant by adjusting the dimension related to the compression amount on the unit to be replaced or by using a spacer.

(Other embodiments)
(A) Other examples of molded products to which the powder molding apparatus of the present invention can be effectively applied are shown in FIGS. 9 (c), (d) and (e).
The molded product P2 shown in FIG. 9C has only the center through hole Hc. In this case, the lower punch unit may include only the center core 4 as a core. In another example, by providing three or more cores, the molded product P1 can be applied to a molded product having multiple side through holes on the outside of the side through holes Hs.

A molded product P3 shown in FIG. 9D has a relatively small protrusion amount of the center core 4 with respect to the end face 24 of the lower punch 2, and forms a recess Lm in the molded product.
The molded product P4 shown in FIG. 9 (e) has a lower end surface 42 of the center core 4 than the end surface 24 of the lower punch 2, and forms a convex portion Lp on the molded product. That is, it corresponds to a concentric stepped molded article described in Patent Document 1 which is a conventional technique. It is also effective to combine the molded product P4 with the through holes Hs and Hc as in the molded product P1.

(I) (Delete)

(C) If you have a multiple core cylinder, it is possible use for changing the drive stroke move the corresponding core by the time difference. Thereby, for example, when the pressurization stroke and the load are different depending on the part as in insert molding, various powder moldings according to the molded product can be realized.

(D) The side core cylinder 37, the center core cylinder 37 of the lower punch unit 20, the lower cylinder 71 of the die drive unit 70, and the upper cylinder 81 of the upper punch drive unit 80 are not limited to hydraulic cylinders as in the above embodiment. For example, an electric actuator using a servo motor and a ball screw may be used. In this case, the stroke is not limited to the two-position actuator that restricts only the forward limit and the reverse limit, and the stroke may be arbitrarily adjustable. When an actuator capable of adjusting the stroke is used, it becomes easy to change conditions when the lower punch unit 20 or the like is replaced, and to make fine adjustments associated with die wear.
As mentioned above, this invention is not limited to such embodiment, In the range which does not deviate from the meaning of invention, it can implement with a various form.

100 ... Powder molding apparatus, 11 ... Base plate,
17 ... Die plate, 18 ... Upper punch plate,
20 ... lower punch unit, 2 ... lower punch,
3 ... side core (core),
37 ・ ・ ・ Side core cylinder (core actuator),
4 ... Center core (core),
47 ・ ・ ・ Center core cylinder (core actuator),
5 ... Die, 51 ... Mold hole,
6 ・ ・ ・ Upper punch,
70 ... Die drive unit, 80 ... Upper punch drive unit,
C: cavity, M: powder material.

Claims (2)

A die (5) in which a mold hole (51) is formed, a lower punch (2) inserted in the mold hole, and a plurality of cores provided separately from the lower punch inside the mold hole ( 3. Press the powder material (M) filled in the cavity (C) defined by 3 and 4) between the lower punch and the upper punch (6) provided to face the lower punch. A powder molding apparatus (100) for molding,
A base plate (11);
A die driving unit (70) capable of driving the die plate (17) supporting the die up and down relative to the base plate;
An upper punch driving section (80) capable of moving the upper punch plate (18) supporting the upper punch up and down with respect to the base plate;
The base plate is mounted on the lower punch, said plurality of cores, and the plurality of the plurality of cores actuators (37, 47) for relatively moving the core relative to the lower punch is a lower punch units assembled together ( 20)
Equipped with a,
The plurality of cores include a center core (4) provided on the center axis of the lower punch, and a plurality of side cores (3) provided along the circumferential direction outside the center core,
The plurality of core actuators include pistons (373, 473) slidable in cylinder chambers (372, 472), base ends coupled to the pistons, and tip ends opposite to the cavities of the core. Including piston rods (374, 474) coupled to a core plate (36, 46) for fixing a flange portion as an end;
In the height direction of the lower punch unit, the piston (373) of the core actuator (37) that drives the side core is coupled with the piston (473) of the core actuator (47) that drives the center core. powder molding according to claim 2, characterized that you have been disposed between the flange portion of the. The cavity is defined by an inner wall (52) of the mold cavity, an end face (24) of the lower punch, and an outer wall (31, 41) of the core protruding from the end face of the lower punch,
The powder molding apparatus according to claim 1 , wherein a molded product (P1, P2) having a through hole (Hs, Hc) corresponding to the shape of the core can be molded.

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