JPH0665606A - Mold for powder molding - Google Patents

Abstract

PURPOSE:To provide the mold for powder molding which can be commonly used simply by partially attaching and detaching one of the constituting parts of dies to and from these dies at the time of separately forming powder molded parts having recessed parts for positioning and powder molded parts having projecting parts. CONSTITUTION:This mold 1 for powder molding has the dies 2 for producing a pair of the powder molded parts having the projecting parts on one of these parts and the recessed parts for positioning by being fitted to these projecting parts on the other and having the same shape in the other parts and is used to form the powder molded parts having a pair of partial gears of the same shape in the positions relatively deviated in a circumferential direction by fitting the projecting parts and the recessed parts of a pair of the powder molded parts. The dies 2 are so formed as to have die holes 200 for forming the projecting parts and to have attaching and detaching die members 201 which attachably and detachably fit into these die holes 200 and form the recessed parts of the powder molded parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder molding die.

[0002]

[Prior art]

(1) Conventionally, for example, as shown in FIG.
The partial gears 41a, 51a at two positions that are in phase with each other and are relatively displaced in the circumferential direction (arrow S, the same applies hereinafter).
As a powder-molding die used for powder-molding the powder-molded product 3a provided with, an Olivetti-type mold is known [edited by Japan Powder Metallurgical Industry Association, published by Gijutsu Shoin Co., Ltd. 2.29 of "Making machine parts, their design and manufacture"].

This Olivetti mold uses two upper and lower dies and presses the upper mold and the lower mold in a direction in which they approach each other, and the product after powder molding can be easily extracted from the mold. It has the advantage that
On the other hand, however, the Olivetti-type mold requires a double-pressing device that presses the upper mold and the lower mold in a direction in which they approach each other, which increases the equipment cost.

Furthermore, two partial gears 41a and 51a
When powder-molding a product with various relative angles in the circumferential direction, each time the relative angle is changed, a plurality of types of molding dies corresponding to this are required, and each time, molding is performed. The product cost increases due to the fact that a large amount of time is required for setup preparation for die replacement. (2) Therefore, without using the Olivetti-type mold, the first powder molded part 4 having the partial gear 410 in advance (see FIG. 7) and the second powder molded part 5 having the partial gear 510 are used.
(See FIG. 8) After being divided into two parts and formed separately, the two parts 4 and 5 are integrally joined, so that two partial gears 410 and 510 are provided at positions relatively displaced in the circumferential direction. It is conceivable to obtain one product 3 (see FIG. 9).

[0005]

However, in the case of the above (2), when the first powder molding part 4 and the second powder molding part 5 are integrally joined to form the powder molding product 3, ,
As the positioning for performing the alignment in advance, for example,
Two recesses 44 on the facing flat surface 43 of the first powder molded part 4,
44 is formed in advance, and the opposing flat surface 5 of the second powder molded component 5 is formed.
It is necessary to form two convex portions 54, 54 on the substrate 3. Therefore, both parts 4 and 5 do not have symmetrical shapes, and two types of powder molding dies are required. That is, it is uneconomical because one powder molding die cannot be shared.

According to the present invention, when the powder molded component having the positioning concave portion and the powder molded component having the convex portion are separately formed, one of the constituent mold components is partially attached to and detached from the lower mold. The purpose of the present invention is to provide a mold for powder molding which can be commonly used.

[0007]

The powder molding die of the first invention has a convex portion on one side and a concave portion on the other side for positioning by fitting with the convex portion. A lower die for manufacturing a pair of powder molded parts each having the same shape is provided, and the convex parts and the concave parts of the pair of powder molded parts are fitted to each other so as to be relatively displaced in the circumferential direction. A powder molding die for forming a powder molding product having a pair of partial gears of the same shape at a position, wherein the lower mold has a mold cavity that forms the convex portion, and is attached to and detached from the mold cavity. It is characterized in that it has a detachable member that fits as much as possible and forms the recess of the powder molded part.

A powder molding die according to a second aspect of the present invention is the powder molding die according to the first aspect of the present invention, wherein the lower die is an outer peripheral portion forming a partial gear portion of the powder molding product, and a convex portion of the powder molding product. And an inner peripheral portion forming the concave portion, and the outer peripheral portion and the inner peripheral portion are relatively rotatable.

[0009]

[Action]

(1) The powder molding die of the first invention is a pair of powder molding parts constituting a powder molding product having a pair of partial gears of the same shape. One has a convex portion and the other has the convex portion. It is used to separately manufacture those having a concave portion that is aligned by fitting and having the other portions of the same shape.

First, when manufacturing a powder molded part having a recess, a detachable mold member for forming the recess is used in a state of being fitted in a mold cavity of a lower mold. This removable member projects into the cavity space forming the powder molded part and becomes a part of the cavity surface forming the recess. Then, the powder filled in the cavity space from which the detachable member protrudes is press-molded to be manufactured as a powder-molded component having a concave portion and a partial gear portion.

Further, in the case of manufacturing a powder molded part having a convex portion, the detachable mold member is not fitted in the mold cavity of the lower mold for forming the convex portion. This mold cavity
It becomes a part of the cavity space for forming the convex portion of the powder molded part, and the wall surface of the mold cavity becomes a part of the cavity surface. Then, the powder filled in the mold cavity is press-molded in the same manner as the powder filled in the other cavity spaces, and is manufactured as a powder molded part having a convex portion and a partial gear portion. (2) The powder molding die of the second invention is the powder molding die of the first invention, wherein the convex portion and the concave portion of the pair of powder molding parts are fitted to each other so as to be relatively displaced in the circumferential direction. It is used when manufacturing a pair of partial gears of the same shape in different positions by changing their positions.

The lower mold is prepared as a preparation prior to use.
An outer peripheral part forming a partial gear of the pair of powder molded parts and an inner peripheral part forming a convex part and a concave part for positioning the pair of powder molded parts are relatively rotated by a predetermined amount (angle). It is set at a target position relatively displaced in the circumferential direction. After that, the positions of the outer peripheral portion and the inner peripheral portion are fixedly held by a predetermined means, and a pair of powder molded parts are separately manufactured in the same manner as in (1) above.

The powder molded part having the convex portion and the partial gear and the powder molded part having the concave portion and the partial gear manufactured in the above (1) or (2) are then separated into the convex portion and the concave portion. By fitting, they are aligned and joined together. As a result, a powder molded product having a pair of partial gears of the same shape is obtained at positions where the pair of powder molded parts are relatively displaced in the circumferential direction.

[0014]

EXAMPLES Examples of the powder molding die of the present invention will be described below with reference to FIGS. Mold 1 for powder molding of Example
(See FIGS. 1 to 4) is characterized by the lower mold 2 and is a pair of first powder molded parts 4 (see FIG. 7) and second powder molded parts that are components of the powder molded product 3 (see FIG. 9). 5 (see FIG. 8) are manufactured separately. Before describing the powder molding die 1, the powder molded product 3 will be described in advance.

The powder molded product 3 serves as a thick, substantially ring-shaped gear member, and the first and second powder molded parts 4 and 5 are integrally formed with opposing flat surfaces 43 and 53. Has a central hole 30 to which a central axis (not shown) is attached in the center, and is aligned in a direction along the axis P (upper and lower in FIG. 9) in a part of the outer peripheral portion, and further in the circumferential direction (arrow S). , Etc.) and the partial gear 41 at two positions 180 ° apart from each other.
There are 0 and 510.

The first powder molded part 4 has a central hole 40 at the center.
A partial gear 410 is formed on a part of the outer peripheral side surface 41, and two concave portions 44, 44 for positioning are circumferentially formed on the opposing flat surface 43 joined to the opposing flat surface 53 of the second powder molded component 5. It is formed so as to maintain a space of 180 °. Second
The powder molded part 5 is the recess 4 of the first powder molded part 4.
The convex portions 54, 54 that fit into the flat surfaces 4, 44
It is formed on the opposed flat surface 53 at a position opposed to 3. Further, on the outer peripheral side surface 51 of the second powder molded part 5, the partial gear 5
10 are formed. The second powder molded component 5 has the same symmetric shape as the shape of the first powder molded component 4 except for the recesses 44, 44, except for the convex portions 54, 54.

The two recesses 4 of the first powder molding part 4
4, 44 and the two convex portions 54, 5 of the second powder molding part 5.
4 is 180 ° in the circumferential direction between the partial gear 410 of the first powder molding part 4 and the partial gear 510 of the second powder molding part 5.
They are fitted to each other in a phased position and serve as so-called positioning. And the pair of first
The powder molded part 4 and the second powder molded part 5 have a recess 44,
44 and the convex portions 54, 54 to position the opposing flat surface 4
3 and 53 are joined and integrated to obtain a powder molded product 3. The powder molded product 3 includes two partial gears 41
0 and 510 are in phase with each other in the direction along the axis P and are present at positions displaced in the circumferential direction.

Next, the powder molding die 1 will be described. As shown in FIGS. 1 to 4, the powder molding die 1 includes a core 10, a die 11, an upper die 12, and a lower die 2. The core 10 has a substantially columnar shape and is arranged at the center position of the powder molding die 1, and has a center hole 40 of the first powder molding part 4.
And the central hole 50 of the second powder molded part 5 is formed.

The die 11 is provided on a part of the die wall surface 110,
It has a partial gear mold 111 for forming the partial gear 410 of the first powder molded part 4 and the partial gear 510 of the second powder molded part 5, and is arranged concentrically with the core 10 at a constant interval. And, by the device not shown, the lower mold 2
It is movable in the vertical direction (direction along the axis P ₁ ). The die 11 includes a core 10 and an upper die 12.
And a lower mold 2 for cavitation space 1a (see FIG. 1) for manufacturing the first powder molding part 4 and cavities space 1b (see FIG. 3) for manufacturing the second powder molding part 5
To form.

The upper die 12 is arranged in a ring-shaped space between the core 10 and the die 11 at a position facing the lower die 2 so as to be vertically movable, and by means of a press device (not shown), the cavity space 1a and the cavity space 1a. The raw material powder filled in the space 1b is pressed at a predetermined pressure, and the flat surface 42 of the first powder molding part 4 opposite to the facing flat surface 43 and the second powder molding part 5 of the facing flat surface 53 opposite side. To form a flat surface 52.

The lower mold 2 is held at a predetermined position by a holding device (not shown), and the facing flat surface 43 of the first powder molding component 4, the recesses 44 and 44 opening to the facing flat surface 43, and the second powder molding component 5 are formed. And a convex portion 54, 54 projecting from the facing flat surface 53, which are concentric with each other and are arranged to be rotatable relative to each other around the core 10, and an outer circumference. And a part 21.

The inner peripheral portion 20 is formed on the inner peripheral sides of the concave portions 44, 44 of the first powder molding part 4 and the facing flat surface 43 and on the inner peripheral sides of the convex portions 54, 54 of the second powder molding part 5 and the facing flat surface 53. To form. Therefore, in the inner peripheral portion 20, the mold cavity 2 having a hole diameter corresponding to the size of the convex portions 54, 54 is formed.
00 and 200, detachable die members 201 and 201 that are detachable from the die holes 200 and 200 from above and correspond to the sizes of the recesses 44 and 44, and die holes 200 and 200 in FIGS. It is provided with movable mold members 202, 202 whose vertical movement amount can be controlled from the lower side.

The mold cavities 200, 200 have convex portions 54, 5
It becomes a part of the cavity space 1b for forming 4
Therefore, the positions that keep 180 ° in the circumferential direction from each other
At center line P₁Are provided in parallel along with the hole diameter is φ
It is set to 4.02 to 4.04 mm. Also the mold cavity 2
00 and 200, the two convex portions 5 of the second powder molded part 5 are provided.
Two detachable mold members 201, 2 for molding 4, 54
01 can be detachably fitted from the upper side in FIGS.
It has become. That is, the removable members 201, 201
Is one of the cavity surfaces for forming the recesses 44, 44.
As shown in Fig. 6, taper to the tip.
The large-diameter portion a having a surface a1 and the lower end side is the mold cavity 20.
Consists of a small diameter part b that can be removably fitted to 0,200
It is a cylinder. Also, the tip diameter of the removable members 201, 201
Outer diameter D of large part a ₁Is φ 4.1 to 4.12 mm, large tip diameter
The length of the portion a is 5 mm, the taper angle θ is 30 °, and the small diameter portion b
Outer diameter D₂Is 3.98 to 4.0 mm, the length of the small diameter part b
Is preset to 10 mm. The removable member 2
No large diameter tip a of 01, 201 is tapered surface a1 shape
The reason is that the powder molding die 1 of this example is used.
As the first powder molded part 4 is manufactured, the cavity
The raw material powder filled in the space 1a is part of the cavity space 1a.
Even if the detachable members 201, 201 are projected to the part,
Tapered surface a of large tip a₁Easy to flow along, and
Since the raw material powder can be densely packed around the tip large diameter portion a as well.
Is.

The movable mold members 202, 202 are formed in the mold cavity 2
00, 200 are mounted so that the vertical movement amount can be controlled from the lower side on the opposite side to the upper side on which the removable members 201, 201 are fitted, and the second powder molded component 5 to be molded is attached. The projecting length of the convex portions 54, 54 (the projecting length from the facing flat surface 53 of the second powder molded component 5) can be set according to the purpose. This movable mold member 202, 20
The outer diameter of 2 is set to φ3.98 to 4.0 mm.

The outer peripheral portion 21 forms an outer peripheral side of the partial gear 410 of the first powder molding part 4 and the facing flat surface 43 and an outer peripheral side of the partial gear 510 of the second powder molding part 5 and the facing flat surface 53. . The powder-molding die 1 configured in this way has the cavite space 1a according to the following specification (1) when the first powder-molded part 4 is prepared in advance and manufactured.
(See FIG. 1), and when the second powder molded part 5 is manufactured, according to the specification of (2) below, the cavity space 1b (see FIG. 3) is set. It

When manufacturing the first powder molded part 4 and the second powder molded part 5, raw material powders are prepared in advance. As the raw material powder, 2% by weight of Cu (copper),
0.6% by weight of Gr (graphite), 0.6% by weight of (CH ₃ (CH ₂ ) ₁₆ CO ₂ ) ₂ Zn (zinc stearate) as a lubricant, and 96.8% by weight of Fe. The blended product is mixed for 20 minutes.

This raw material powder is used in the cavity space 1
After being filled in a or 1b, it is pressure-molded at a surface pressure of 5 ton / cm ² by the upper mold 12 which is interlocked with a general-purpose press device (not shown). That is, (1) In the case of manufacturing the first powder molding part 4 shown in FIG. 7, in the mold cavities 200, 200 formed in the inner peripheral portion 20 of the lower mold 2 of the powder molding mold 1, As shown in FIG. 1, the detachable members 201, 201 are used in a fitted state. Therefore, the removable members 201, 201 project into the cavity space 1a forming the first powder molded part 4 and become a part of the cavity surface. And detachable members 201, 2
The raw material powder filled in the cavity 1a in which 01 is projected is press-molded by the core 10, the die 11, the upper mold 12, and the lower mold 2, and the first powder molding part having the recesses 44, 44 and the partial gear part 410 is formed. Manufactured as 4. (2) In the case of manufacturing the second powder molding part 5 shown in FIG. 8, in the mold cavities 200 and 200 formed in the inner peripheral portion 20 of the lower mold 2 of the powder molding mold 1, FIG. As shown, the detachable members 201, 201 are used without being fitted. Therefore, the mold cavities 200, 200 for forming the convex portions 54, 54 of the second powder molded part 5 become a part of the cavity space 1b, and the wall surfaces of the mold cavities 200, 200 are a part of the cavity surface. Becomes And the mold cavities 200, 20
The raw material powder filled in the cavity space 1b containing 0 is
It is pressed and molded by the core 10, the die 11, the upper mold 12, and the lower mold 2, and is manufactured as the second powder molded component 5 having the convex portions 54, 54 and the partial gear portion 510. (3) Further, according to the powder molding die 1 of the present embodiment, the phase of the partial gear 410 of the first powder molded part 4 and the partial gear 510 of the second powder molded part 5 in the circumferential direction. When it is necessary to set the angle to, for example, 30 ° rather than the angle of 180 °, the inner peripheral portion 20 of the lower mold 2 is manufactured at the time of manufacturing one of the first powder molded component 4 and the second powder molded component 5. And the outer peripheral portion 21 are rotated relative to each other (the inner peripheral portion 20 and the outer peripheral portion 21 of the lower mold 2 are set to 30 ° as shown in FIG. 5).
The target position S ₂ is rotated in the circumferential direction from the reference position S ₁ so that the same angle θ ₁ is obtained. After this,
Alternatively, the position is fixed and held by the fixing bolt 212 shown in FIG.

Then, a predetermined amount from the reference position S ₁ ,
Either the first powder molding part 4 or the second powder molding part 5 is powder-molded by the powder-molding mold 1 using the lower mold 2 which is relatively rotated in the circumferential direction and whose phase angle is set to 30 °. Manufactured by. In the first powder molded part 4 and the second powder molded part 5 manufactured as described in (1), (2), and (3), the composition component is Cu between the facing flat surfaces 43 and 53, and The brazing material made of Ni, Mn, Si, and B is brought into contact with each other, and the concave portions 44 and 44 of the first powder molded component 4 and the convex portions 54 and 5 of the second powder molded component 5 are contacted with each other.
4 and 4 are aligned and fitted at the matched position. Then, the first powder molded part 4 and the second powder molded part 5 in this state were sintered (simultaneous bonding) at 1120 ° C. for 30 minutes in an inert gas and integrated to obtain a powder molded product 3.

According to the powder-molding die 1 of this embodiment, as the components of the powder-molded product 3, the first powder-molded component 4 having the partial gear 410 and the concave portions 44, 44, the partial gear 510 and the convex portion. Second powder molded part 5 having 54, 54
When the and are separately manufactured, the removable mold members 201, 201, which are one of the component parts of the lower mold 2, can be shared by only being removable from the mold holes 200, 200 of the inner peripheral portion 20. .

Further, the circumference of the partial gear 410 and the partial gear 510 existing on the circumference of the powder molded product 3 obtained by bonding the first powder molded part 4 and the second powder molded part 5 together. The positions that are relatively deviated in the directions are the inner peripheral portion 20 and the outer peripheral portion 21 of the lower mold 2 when the first powder molded component 4 and the second powder molded component 5 are manufactured by the powder molding mold 1. By relatively rotating the target predetermined amount, the formation positions of the concave portions 44, 44 and the convex portions 54, 54 for positioning can be freely set.

Therefore, using the powder molding die 1, the first
When manufacturing the powder molded part 4 and the second powder molded part 5, the manufacturing cost thereof can be reduced. In addition,
In the examples, as the raw material powder, the metal powder mainly made of iron was used, but it is not limited to this, for example, other metal powder, structural ceramic powder,
It can also be applied to those using other powders.

[0032]

【effect】

(1) In the powder molding die of the first aspect of the present invention, a powder molding part having a recess can be formed at the time of powder molding by fitting a removable mold into the mold cavity of the lower mold. Further, by removing the removable mold from the mold hole of the lower mold, the hole into which the removable mold has been fitted becomes a mold hole to form a powder molded part having a convex portion.

Therefore, two kinds of powder molding parts can be formed with one powder molding mold, and two kinds of powder molding parts corresponding to two kinds of powder molding parts having different shapes as in the conventional case can be formed. There is no need to prepare a mold. Furthermore, powder molding can be performed using a general-purpose press machine, and the equipment cost is low. (2) Further, in the powder molding die of the second invention, since the outer peripheral portion and the inner peripheral portion are relatively movable, the relative angle in the circumferential direction between the partial gear and the positioning concave and convex portions can be adjusted. is there.

That is, when it is necessary to form the two partial gears by phasing each in the direction along the axis and shifting the various positions in the circumferential direction as well, the powders on one side and the other side are formed. The outer peripheral part of the mold forming the partial gear of the molded part and the inner peripheral part of the mold forming the concavo-convex part of the one and the other powder molded parts may be relatively rotated in the circumferential direction by a predetermined amount. . For this reason, when it is necessary to change the positions of the pair of partial gears of the powder molded product, which are deviated in the circumferential direction relative to each other, according to the purpose, a concave portion and a convex portion are provided at the corresponding positions. A pair of powder molding parts can be easily manufactured by one powder molding die.

Therefore, it is not necessary to replace the whole mold and to set up, and it is not necessary to prepare several kinds of powder molding dies for shifting the positions in the circumferential direction. The manufacturing cost can be reduced accordingly.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a main part of a powder molding die of the present invention, showing a state in which a removable mold member is fitted in a mold cavity of a lower mold.

2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a cross-sectional view showing a main part of a powder molding die of the present invention, showing a state where a removable mold member is removed from a mold hole of a lower mold.

4 is a sectional view taken along the line AA in FIG.

FIG. 5 is a transverse cross-sectional view showing a state in which an inner peripheral portion and an outer peripheral portion of the lower die of the powder molding die of the present invention are displaced in predetermined positions in the circumferential direction.

FIG. 6 is an enlarged vertical cross-sectional view showing in an enlarged manner a detachable mold member fitted in a mold cavity of the lower mold in FIG.

FIG. 7 is a perspective view showing, in a partial cross section, a powder molded part manufactured using the powder molding mold in the state shown in FIG. 1 and having a recess and a partial gear.

FIG. 8 is a perspective view showing a partial cross-section of a powder molded component having a convex portion and a partial gear, which is manufactured by using the powder molding mold in the state shown in FIG.

9 is a perspective view showing a partial cross section of a powder molded product obtained by integrally joining the powder molded part in FIG. 7 and the powder molded part in FIG.

FIG. 10 is a perspective view showing a powder molded product formed using a conventional Olivetti powder molding die.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Powder-molding die 2 ... Lower mold 20 ... Inner peripheral part 21 ... Outer peripheral part 200 ... Mold hole 201 ... Removable mold member 3 ... Powder molded product 4 ... First powder molded part 40 ... Opposing plane 44 ... Recess 42 ... Recessed portion 410 ... Partial gear 5 ... Second powder molded part 50 ...
Opposing plane 54 ... Convex portion 52 ... Convex portion 510 ... Partial gear

Claims (2)

[Claims] 1. A pair of powder molded parts each having a convex portion on one side, a concave portion for positioning by fitting with the convex portion on the other side, and the other portions having the same shape are manufactured respectively. A powder mold product having a pair of partial gears of the same shape at positions relatively displaced in the circumferential direction by fitting the convex portion and the concave portion of the pair of powder molded parts. A mold for powder molding for forming, wherein the lower mold has a mold cavity for forming the convex portion,
A mold for powder molding, comprising a removable mold member detachably fitted in the mold cavity to form a recess of the powder molded part. 2. The lower mold is composed of an outer peripheral portion forming a partial gear portion of the powder molded product and an inner peripheral portion forming a convex portion and a concave portion of the powder molded product, and the outer peripheral portion and the inner peripheral portion. The powder molding die according to claim 1, wherein the die is capable of relative rotation.