JP2001105193A - Method and device for molding stepped compact - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for molding a stepped compact which can easily fill the powder, transfer the powder to the compaction starting position, position the compression from the simple information on variables mainly including the dimensions of a molding, and simplify the adjusting work. SOLUTION: The adjusting work to obtain a molding of a desired quality is simplified by easily determining the basic processes of filling, transferring and pressing the raw powder from the dimensions of the molding so that the transfer distance of the powder and the moving distance of upper and lower punches corresponding to molding components are uniquely obtained from the definition of the molding and the coefficient of compaction. The neutral lines in the respective molding components are made coincident with each other by satisfying the conditions of predetermined formulae, and the molding accuracy is further improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of molding powder, and more particularly, to a method of compressing a powder filled in a die by upper and lower punches to form a stepped shape having different thicknesses in the compression direction. The present invention relates to a stepped powder molding method and a stepped powder molding apparatus for molding a body.

[0002]

2. Description of the Related Art (1) Multi-stage pressing using a press machine operated by a balance mechanism Compression molding of powder to form a stepped shape with different thicknesses in the compression direction One of the conventional molding methods for obtaining a body is a method of performing a multi-stage press using a press machine operated by a balance mechanism.

In this method, the driving of another divided mold and the pressing of powder are adjusted by a balance mechanism using a force such as air pressure, a spring, or a hydraulic pressure with respect to the main pressure of each of the upper and lower shafts. This is a method of performing multi-stage molding by executing a basic process of powder filling, transfer to a compression start position, and pressurization (compression).

However, in the case of this method, powder filling, transfer to a compression start position, and pressurization (compression) are performed.
In addition to the unstable operation of each of the above, it is necessary to conduct a preliminary test to obtain data on the shape and dimensions of the product each time when the properties of the raw materials and the differences in the mold area are changed. In addition, the efficiency is low. For example, the filling amount of the powder and the moving distance (pressing amount) of the movable punch are set so that the target density is gradually reached from safe conditions so that the mold is not damaged. It is necessary to determine the molding conditions step by step by adjusting
There are problems such as the need for labor and the need for an operator who is familiar with specialized skills to repeat advanced adjustment techniques and complicated check operations.

(2) CNC multi-stage pressing method As a molding method for compressing powder and obtaining a stepped shaped body having a thickness different in a compression direction, a press machine operated by the above-mentioned balance mechanism is used. In addition to the multi-stage press method, there is a method of performing multi-stage press molding by numerical control using a computer (CNC multi-stage press method).

In the case of the CNC multi-stage press method, the operations of filling the powder, transferring the powder to the compression start position, and pressing (compressing) can be defined with certainty. Unlike the multi-stage pressing method using a press machine, it is not necessary to adjust the filling of powder, transfer to a compression start position, pressurization (compression), and the like by a balance mechanism.

However, in the case of the CNC multi-stage press method, it is necessary to accurately determine in advance the powder supply position, the transfer position, the punch position at the time of compression, and the like. In order to perform detailed position determination for each area, it is necessary not only to perform complicated confirmation work based on advanced molding knowledge and experience, but also to check the balance of the molded body after position determination, It is necessary to adjust the position.Particularly, the actual operation differs between the case of the die float system and the case of the die fixing system. Is required, and there is a problem that it is complicated.

The present invention is intended to solve the above-mentioned problem. In the case where a multi-stage press forming by numerical control is performed to form a stepped shaped body having a thickness different in a compression direction, powder filling is performed. The transfer of the powder to the compression start position and the determination of the position of the pressurization (compression) can be easily performed based on simple variable information, mainly on the size of the compact, and the adjustment work is simplified. An object of the present invention is to provide a stepped shape powder molding method and a stepped shape powder molding apparatus that can perform the method.

[0009]

In order to achieve the above object, a stepped powder molding method according to the present invention (claim 1) corresponds to a die to be filled with powder and the number of steps of the compact. Using a molding device equipped with a plurality of pairs of upper and lower punches, the powder is filled into the die, and the upper and lower punches are moved in the vertical direction, thereby compressing the powder that has been filled into the die and constituting each molded body component. After transferring a predetermined distance (transfer distance) to the start position, the powder is compressed by moving the corresponding upper and lower punches by a predetermined distance (movement distance) in the vertical direction with respect to each of the molded component parts. In the step-shaped powder molding method for molding into a stepped shape, the transfer distance of the powder and the moving distance of each of the upper and lower punches and the die corresponding to the molded component are calculated by the following formula. It is characterized by It is. F1: height of the first compact component before compression F2: height of the second compact component before compression Fn: height of the n-th compact component before compression H1: after compression H2: height of the second molded body component after compression molding Hn: height of the n-th molded body component after compression molding S2: height of the nth molded body component after compression molding Distance from the lower end of the first molded component to the lower end of the second molded component Sn: From the lower end of the first molded component to the lower end of the n-th molded component after compression molding R1a: Compression coefficient by the first upper punch P1a R1b: Compression coefficient by the first lower punch P1b R2a: Compression coefficient by the second upper punch P2a R2b: Compression coefficient by the second lower punch P2b Rna: n, the compression coefficient of the upper punch Pna Rnb: Compression coefficient by the n-th upper punch Pnb X1a · 1b: First upper punch P1a and lower punch P1
x2a · 2b: second upper punch P2a and lower punch P2
xna × nb: n-th upper punch Pna and lower punch Pn
XD: Moving distance of the die M1: Transfer distance of the first molded component before compression M2: Transfer distance of the second molded component before compression Mn: n-th molding before compression Transfer distance of body constituent part Plus (+) sign: Upward movement Minus (-) sign: Downward movement: (1) Movement distance of first upper and lower punches P1 Total compression amount (total travel distance) (X
1a.1b) X1a.1b = F1-H1 Moving distance (X1a) of upper punch P1a of first upper and lower punches P1 X1a = -X1a.1b + X1a.1bR1b + XD or X1a = -X1a.1bR1a + XD First upper and lower punches X1b = X1a.1b-X1a.1bR1a + XD or X1b = X1a.1bR1b + XD (where R1a + R1b = 1) (2) Moving distance of the second upper and lower punches P2 Compression amount of the upper and lower punches P2 (total moving distance) (X
2a / 2b) X2a / 2b = F2-H2 Moving distance of upper punch P2a of second upper / lower punch P2 (X2a) X2a = -X2a / 2b + X2a / 2bR2b + XD of lower punch P2b of second upper / lower punch P2 Movement distance (X2b) X2b = X2a · 2b−X2a · 2bR2a + XD (where R2a + R2b = 1) (3) Movement distance of nth upper / lower punch Pn Total compression amount of nth upper / lower punch Pn (total movement distance) Xna · nb = Fn-Hn The moving distance (Xna) of the upper punch Pna among the nth upper and lower punches Pn Xna = -Xna.nb + Xna.nbRnb + XD The moving distance (Xnb) of the lower punch Pnb of the nth upper and lower punches Pn Xnb = Xna · nb−Xna · nbRna + XD (where Rna + Rnb = 1) (4) First compression before compression Transfer distance of body component (M1) M1 = Fs-F1- (Xsb + S1-X1b) (5) Transfer distance of second formed body component before compression (M2) M2 = Fs-F2- (Xsb + S2-X2b) (6) Transfer distance (Mn) of the n-th molded body component before compression Mn = Fs-Fn- (Xsb + Sn-Xnb) (However, in (4) to (6), any of Fs: F1 to Fn Xsb: reference movement distance of lower punch arbitrarily selected from X1b to Xnb)

The powder transfer distance and the moving distance (compression amount) of each of the upper and lower punches corresponding to the constituent parts of the compact are determined by the above equations, so that the powder material can be charged, transferred, pressurized (compressed). The basic process of (1) can be easily determined from the dimensions of the molded body, and the adjustment work for molding the molded body is drastically simplified, so that a molded body of a desired quality can be efficiently formed. Becomes possible. The step-shaped powder molding method of the present invention can be applied to both a die float method in which a die moves and a die fixing method. Filling,
The basic steps of transfer and pressurization can be easily determined from the dimensions of the molded body.

According to a second aspect of the present invention, in the stepped powder molding method, a lower punch of any one of the plurality of pairs of upper and lower punches is set as a fixed shaft, and a moving distance of the fixed shaft is set to zero. It is characterized by.

In the case of the die float system in which the die is moved, of the plural pairs of upper and lower punches, the lower punch of any one axis is set as a fixed axis, and the moving distance of the fixed axis is set to 0, so that the die is moved. The moving distance can be obtained.

According to a third aspect of the present invention, there is provided the stepped powder molding method, wherein the die is a fixed shaft, and a moving distance of the fixed shaft is 0.
It is characterized by the following.

The stepped powder molding method according to the third aspect relates to a molding method of a die fixing system in which molding is performed without moving the die. In the case of the die fixing system, the die does not move. By setting the variable XD representing the movement of the die to 0 in the case of the step-shaped powder molding method of claim 1, the movement distance of each upper and lower punch and the transfer distance of the powder can be obtained.

According to a fourth aspect of the present invention, a neutral line (center of pressure) of each component of the molded body is positioned on one horizontal line by satisfying the following condition. It is characterized by having. R1bH1 = R2bH2 + S2 =... = RnbHn + S
n

By satisfying the condition of the above expression, it is possible to make the neutral lines (pressing centers) of the respective components of the molded body coincide, that is, to locate them on one horizontal line, and the neutral lines do not coincide. Thus, it is possible to suppress and prevent the deformation of the molded body and the unevenness of the molding density, thereby reliably producing a molded body with higher dimensional accuracy and shape accuracy.

The stepped powder molding method according to claim 5 is characterized in that the compression speed ratio between the axes of a plurality of pairs of upper and lower punches is made constant.

By making the compression speed ratio between the axes of a plurality of pairs of upper and lower punches constant, the pressing ratio of one upper and lower punch and the pressing ratio of the other upper and lower punch do not differ at a certain point in time. Pressurization can be performed at a constant pressurization ratio. As a result, the powder between the upper and lower punches having a large pressing ratio is prevented from flowing between the upper and lower punches having a small pressing ratio, thereby preventing the occurrence of compression unevenness and keeping the powder density of the obtained molded body constant. It becomes possible to do.

The stepped-shaped powder molding apparatus according to the present invention (claim 6) includes a die for compressing the powder, and a plurality of pairs of upper and lower punches corresponding to the number of stages of the compact. By moving in the direction, the powder filling the die and constituting each compact component is transported a predetermined distance (transport distance) to the compression start position, and then corresponds to each compact component. A step-shaped powder molding apparatus configured such that the powder is compressed by moving the upper and lower punches by a predetermined distance (moving distance) in the vertical direction, and the powder is formed into a stepped shape having a different thickness in the compression direction. Wherein the moving distance of the powder and the moving distance of each of the upper and lower punches and dies corresponding to the component of the molded body are set to values determined by the following equations. And F1: height of the first compact component before compression F2: height of the second compact component before compression Fn: height of the n-th compact component before compression H1: after compression H2: height of the second molded body component after compression molding Hn: height of the n-th molded body component after compression molding S2: height of the nth molded body component after compression molding Distance from the lower end of the first molded component to the lower end of the second molded component Sn: From the lower end of the first molded component to the lower end of the n-th molded component after compression molding R1a: Compression coefficient by the first upper punch P1a R1b: Compression coefficient by the first lower punch P1b R2a: Compression coefficient by the second upper punch P2a R2b: Compression coefficient by the second lower punch P2b Rna: n, the compression coefficient of the upper punch Pna Rnb: Compression coefficient by the n-th upper punch Pnb X1a · 1b: First upper punch P1a and lower punch P1
x2a · 2b: second upper punch P2a and lower punch P2
xna × nb: n-th upper punch Pna and lower punch Pn
XD: Moving distance of the die M1: Transfer distance of the first molded component before compression M2: Transfer distance of the second molded component before compression Mn: n-th molding before compression Transfer distance of body constituent part Plus (+) sign: Upward movement Minus (-) sign: Downward movement: (1) Movement distance of first upper and lower punches P1 Total compression amount (total travel distance) (X
1a.1b) X1a.1b = F1-H1 Moving distance (X1a) of upper punch P1a of first upper and lower punches P1 X1a = -X1a.1b + X1a.1bR1b + XD or X1a = -X1a.1bR1a + XD First upper and lower punches X1b = X1a.1b-X1a.1bR1a + XD or X1b = X1a.1bR1b + XD (where R1a + R1b = 1) (2) Moving distance of the second upper and lower punches P2 Compression amount of the upper and lower punches P2 (total moving distance) (X
2a / 2b) X2a / 2b = F2-H2 Moving distance of upper punch P2a of second upper / lower punch P2 (X2a) X2a = -X2a / 2b + X2a / 2bR2b + XD of lower punch P2b of second upper / lower punch P2 Movement distance (X2b) X2b = X2a · 2b−X2a · 2bR2a + XD (where R2a + R2b = 1) (3) Movement distance of nth upper / lower punch Pn Total compression amount of nth upper / lower punch Pn (total movement distance) Xna · nb = Fn-Hn The moving distance (Xna) of the upper punch Pna among the nth upper and lower punches Pn Xna = -Xna.nb + Xna.nbRnb + XD The moving distance (Xnb) of the lower punch Pnb of the nth upper and lower punches Pn Xnb = Xna · nb−Xna · nbRna + XD (where Rna + Rnb = 1) (4) First compression before compression Transfer distance of body component (M1) M1 = Fs-F1- (Xsb + S1-X1b) (5) Transfer distance of second formed body component before compression (M2) M2 = Fs-F2- (Xsb + S2-X2b) (6) Transfer distance (Mn) of the n-th molded body component before compression Mn = Fs-Fn- (Xsb + Sn-Xnb) (However, in (4) to (6), any of Fs: F1 to Fn Xsb: reference movement distance of lower punch arbitrarily selected from X1b to Xnb)

By using the step-shaped powder molding apparatus having the above-described configuration, the step-shaped powder molding method of the present invention (claim 1) is surely carried out, the distortion is small, and the dimensional accuracy is reduced. In addition, it is possible to reliably manufacture a molded body having high shape accuracy.

The stepped powder molding apparatus according to claim 7, wherein the lower punch of any one of the plurality of pairs of upper and lower punches is configured as a fixed shaft. A molding apparatus, wherein the moving distance of the fixed shaft is set to zero.

According to a seventh aspect of the present invention, there is provided a step-shaped powder molding apparatus of a die float type for performing molding by moving a die. By carrying out the step-shaped powder molding method of the present invention (claim 2) of the float system without fail, it is possible to reliably produce a molded product with little distortion and high dimensional accuracy and shape accuracy.

The stepped powder molding apparatus according to claim 8 is a stepped powder molding apparatus in which the die is configured as a fixed shaft, wherein the moving distance of the fixed shaft is zero. It is characterized by the following.

The stepped-shaped powder molding apparatus according to claim 8 is a die-fixed stepped-shaped powder molding apparatus for performing molding without moving the die. Invention of the present application of the die fixing method (Claim 3)
The stepped shape powder molding method described above is surely carried out, and it is possible to reliably produce a molded body having small distortion, high dimensional accuracy and high shape accuracy.

Further, in the step-shaped powder molding apparatus according to the ninth aspect, by satisfying the following condition, the neutral line (pressing center) of each molded component is positioned on one horizontal line. It is characterized by being constituted. R1bH1 = R2bH2 + S2 =... = RnbHn + S
n

By using the molding apparatus having the above-described configuration, the stepped powder molding method of the present invention (claim 4) is carried out, and the neutral lines (pressing centers) of the respective constituent parts of the molded bodies are made to coincide with each other. This makes it possible to suppress and prevent deformation of the molded product due to the mismatch of the neutral line and deviation of the molded density, and to reliably produce a molded product with higher dimensional accuracy and shape accuracy. .

Further, the stepped powder molding apparatus according to the tenth aspect is characterized in that the compression speed ratio between the axes of a plurality of pairs of upper and lower punches is made constant.

By using the molding apparatus having the above configuration, it is possible to carry out the stepped powder molding method of the present invention (claim 5). It is possible to prevent the powder between the upper and lower punches having a large pressing ratio from flowing into the upper and lower punches having a small pressing ratio by eliminating the difference between the pressing ratio of the upper and lower punches and the pressing ratio of the other upper and lower punches. As a result, the powder density of the compact can be made constant.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be shown and the features thereof will be described in more detail.

[Embodiment 1] In Embodiment 1, a case will be described as an example in which the moving distance of each punch and the moving distance of powder are obtained in the case of a die float system in which molding is performed while moving a die. FIG. 1 is a view showing a basic concept of a stepped shape powder molding method (in the case of a die float method) according to an embodiment (Embodiment 1) of the present invention.

In this embodiment, as shown in FIG. 1, a die D, an upper punch P1a and a lower punch P1b that form a first upper and lower punch P1, and an upper punch P2a that forms a second upper and lower punch P2. As shown in FIGS. 2 (a), 2 (b) and 2 (c), using a forming apparatus provided with a lower punch P2b,
A description will be given of a case where a molded body 10 having a structure in which a non-penetrating portion (second molded body constituent part) 2 is disposed inside a cylindrical portion (first molded body constituent part) 1 will be described. However, in FIG. 1, for convenience, the shape of
It can be molded with a two-shaft / lower-shaft mold configuration.
The description will be made assuming the shape of the solid line portion in (c).

First, the definitions of various variables will be described with reference to FIGS. F1: Height of the first compact component before compression (filling height of powder) (FIG. 1) F1 is the cylindrical portion (first compact component) 1 of the compact after compaction The height (=) of the first compact component (powder) 1a (FIG. 1) before compression, which constitutes (FIG. 2)
(Filling height of powder). F2: Height of second molded body component before compression (filling height of powder) (FIG. 1) F2 is a non-penetrating part (second molded body component) 2 of the molded body after molding This is the height (= filling height of powder) of the second compact component 2a (FIG. 1) before compression, which constitutes (FIG. 2). Fn: Height of the n-th molded component before compression (vertical distance) As shown in FIG. 2, the molded product of this embodiment has a first molded component 1 as a molded component. And F2 (Fn) in the case where there is still another molded body component 3 (n) a as shown in FIG. 3 (a), for example. Things.

H1: Height of the first molded component after compression molding (FIG. 2 (c)) As shown in FIG. 2 (c), H1 is the height of the molded product 10 after the molding is completed. Cylindrical portion (first molded component) 1
Height. H2: Height of second compact component after compression molding (FIG. 2)
(c)) As shown in FIG. 2 (c), this H2 is a non-penetrating part (second molded body constituent part) 2 of the molded body 10 after the molding is completed.
Height. Hn: Height of n-th molded component after compression molding As shown in FIG. 2 (c), the molded product of this embodiment has the first molded component 1 and the first molded component 1 as molded components. Although only the molded body component 2 is provided, as shown in FIG. 3 (b), H when there is another molded body component 3 (n)
3 (Hn).

S2: Distance from the lower end of the first molded component to the lower end of the second molded component after compression molding. Sn: From the lower end of the first molded component after compression molding. Distance to the lower end of the n-th molded component As shown in FIG. 2, the molded product of this embodiment has a first molded component 1 and a second molded component as molded components. 3, but assuming that there is still another molded part 3 (n) as shown in FIG. 3 (b), the concept of Sn is introduced and the first molded part 1 Is assumed as a distance S3 (Sn) from the lower end of the third molded body component 3 (n) to the lower end of the third (n) molded body component 3 (n).

R1a: Compression coefficient by the first upper punch P1a The compression coefficient is a coefficient for determining the moving ratio of the upper punch and the lower punch necessary for each pressurization when each component of the compact is compressed by the upper and lower punches. R1a is a coefficient that determines the rate at which the first upper punch P1a (FIG. 1) moves downward. R1b: Compression coefficient by the first lower punch P1b This R1b is a coefficient that determines the rate at which the first lower punch P1b (FIG. 1) moves upward. R2a: Compression coefficient by the second upper punch P2a This R2a is a coefficient that determines the rate at which the second upper punch P2a (FIG. 1) moves downward. R2b: Compression coefficient by the second lower punch P2b This R2b is a coefficient that determines the rate at which the second lower punch P2b (FIG. 1) moves upward. Rna: Compression coefficient by the n-th upper punch Pna Rnb: Compression coefficient by the n-th lower punch Pnb As shown in FIG. 2, the molded body of this embodiment has a first molded body constituent part as a molded body constituent part. Only the first and second molded component parts 2 are provided, and as shown in FIG. 1, it is possible to mold only with the first and second upper and lower punches, but the above Rna and Rnb are further Other (nth
1) assumes the use of upper and lower punches.

For example, as shown in FIG. 3B, a portion above the neutral line NL1 of the first molded component 1 is denoted by A, a portion below the neutral line NL1 is denoted by B, and a second molded component is denoted by B. A above the neutral line NL2 and b below the neutral line NL2. Further, when the portion above the neutral line NL3 of the third (n) molded body component is α and the lower portion is β. , R1a, R1b, R2a, R2
b, R3a (Rna), R3b (Rnb) and A, B,
The following relationship is established among a, b, α, and β. A: B = R1a: R1b a: b = R2a: R2b α: β = R3a (Rna): R3b (Rnb) The compression coefficient depends on the properties of the powder and the shape characteristics of the molded body. It is a value that can be determined as appropriate.

X1a and 1b: total compression amount by first upper punch P1a and lower punch P1b X2a and 2b: second upper punch P2a and lower punch P2
xna × nb: n-th upper punch Pna and lower punch Pn
x1a · 1b, X2a · 2b, and Xna · nb
Are the total compression amounts (total pressurization amounts) for compressing the powder to the target thickness of the compact by the first to n-th upper punches and lower punches, respectively. Is distributed to each upper punch and lower punch. That is, X1a · 1b,
X2a · 2b and Xna · nb are the total values of the moving distances of the first, second, and n-th upper punches and lower punches. Note that it is possible to express the compression amount as a real number by separating it into upper and lower parts, or to express the total compression amount by an upper and lower ratio distribution, but the purpose is the same.

XD: Moving distance of die The value of XD is 0 (XD =
0)

M1: first molded component before compression
Minute transfer distance M2: transfer distance of the second compact component before compression M2 is the powder material (the second compact component)
Before pressing the powder raw material to be
To the position where pressurization starts without performing pressure (pressurization start point).
(In this embodiment, downward)
It is. Note that, here, the first molded component part 1 is used.
Since the powder 1a to be used is a reference, the first compact
What is the transfer distance (M1) of the powder 1a that should become the component 1?
It doesn't matter.  Mn: Transfer distance of n-th molded body component before compression The molded body of this embodiment has a molded body structure as shown in FIG.
As a component, a first molded component 1 and a second molded component
Although only the component 2 is provided, as shown in FIG.
In addition, there is a case where there is a further molded component 3 (n) and the like.
Assuming, in this case, the third molded component 3 (n)
Assuming transfer distance M3 (Mn) of raw material powder 3 (n) a to be
It was done. Note that the upper punch, lower punch, and
For the die and die movements, the plus (+) sign indicates upward movement.
Movement, the minus (-) sign indicates downward movement.
You.

Next, a method for obtaining the moving distance of each punch and the moving distance of the powder (compacted body component) by using the above variables will be described. (1) Moving distance of first upper and lower punches P1 Total compression amount (total moving distance) of first upper and lower punches P1 (X
1a.1b) X1a.1b = F1-H1 Moving distance (X1a) of upper punch P1a of first upper and lower punches P1 X1a = -X1a.1b + X1a.1bR1b + XD or X1a = -X1a.1bR1a + XD First upper and lower punches X1b = X1a.1b-X1a.1bR1a + XD or X1b = X1a.1bR1b + XD (However, R1a + R1b = 1) In the case of the die float method, the lower punch P1 is usually used.
b is fixed, in which case X1b = 0, and
XD becomes XD =-(F1-H1) R1b. FIG. 4 shows the basic operation of the multi-stage press and the positional relationship of the compact when the lower punch P1b is fixed.

(2) Moving distance of second upper / lower punch P2 Total compression amount (total moving distance) of second upper / lower punch P1 (X2a / 2b) X2a / 2b = F2-H2 Of second upper / lower punch P2 X2a = −X2a · 2b + X2a · 2bR2b + XD = − (F2-H2) + (F2-H2) R2b− (F1-H1) R1b = (F2-H2) (R2b−1) -(F1-H1) R1b Moving distance (X2b) of lower punch P2b of second upper and lower punches P2 X2b = X2a / 2b-X2a / 2bR2a + XD = (F2-H2) R2b- (F1-H1) R1b , R2a + R2b = 1)

(3) Moving distance of the n-th vertical punch Pn Total compression amount (total moving distance) of the n-th vertical punch Pn (X
na · nb) Xna · nb = Fn−Hn Moving distance of upper punch Pna of nth upper / lower punches Pn (Xna) Xna = −Xna · nb + Xna · nbRnb + XD of lower punch Pnb of nth upper / lower punches Pn Moving distance (Xnb) Xnb = Xna · nb−Xna · nbRna + XD (However, Rna + Rnb = 1)

(4) Transfer distance (M1) of first molded component before compression (M1) In this embodiment, since the powder 1a constituting the first molded component 1 is not transferred, the transfer distance (M1) M1) is 0. (5) Transfer distance (downward) of the second compact component before compression (M2) M2 = F1-F2- (X2a + S2-X2b) = F1-F2-S2 + (F2-H2) R2b- ( F1-H1) R1b

(6) Transfer distance (Mn) of the component part of the n-th molded body (downward) before compression Mn = Fs-Fn- (Xsb + Sn-Xnb) where (5), (6) In the formula, Fs and Xsb are as follows. Fs: Reference height of a component part arbitrarily selected from F1 to Fn Xsb: Reference movement distance of lower punch arbitrarily selected from X1b to Xnb

As described above, the transfer distance of the powder and the moving distance (compression amount) of each of the upper and lower punches corresponding to the constituent parts of the compact.
From the above equations, it is possible to easily determine the basic steps of filling, transferring, and pressurizing (compressing) the powder raw material from the dimensions of the molded body. This greatly simplifies the adjustment work, and makes it possible to efficiently form a molded body of a desired quality.

[Embodiment 2] In this embodiment 2, FIG.
The case of the die fixing method will be described with reference to FIG.
Since the shape of the molded body and the definition of each variable are the same as those in the first embodiment, the description will be omitted to avoid duplication. In the case of the die fixing method, by setting the variable XD representing the movement of the die to 0, the moving distance of each upper and lower punch and the moving distance of the powder can be obtained as follows.

(1) Moving distance of first upper and lower punches P1 Total compression amount (total moving distance) of first upper and lower punches P1 (X
1a.1b) X1a.1b = F1-H1 Moving distance (X1a) of upper punch P1a of first upper and lower punches P1 X1a = -X1a.1b + X1a.1bR1b or X1a = -X1a.1bR1a First upper and lower punches Moving distance (X1b) of lower punch P1b of P1 X1b = X1a.1b-X1a.1bR1a or (However, R1a + R1b = 1)

(2) Moving distance of second upper / lower punch P2 Total compression amount (total moving distance) of second upper / lower punch P2 (X
2a.2b) X2a.2b = F2-H2 Movement distance of upper punch P2a of second upper and lower punches P2 (X2a) X2a = -X2a.2b + X2a.2bR2b Lower punch P2b of second upper and lower punches P2 Moving distance (X2b) X2b = X2a · 2b−X2a · 2bR2a = (F2-H2) R2b

(3) Moving distance of the n-th vertical punch Pn The total compression amount (total moving distance) of the n-th vertical punch Pn (X
na · nb) Xna · nb = Fn−Hn Moving distance of upper punch Pna of nth upper / lower punches Pn (Xna) Xna = −Xna · nb + Xna · nbRnb Lower punch Pnb of nth upper / lower punches Pn Moving distance (Xnb) Xnb = Xna · nb−Xna · nbRna (however, Rna + Rnb = 1)

(4) Transfer distance (M1) of first compact component before compression In this embodiment, the powder 1a constituting the first compact component 1 is not transferred, so the transfer distance (M1) M1) is 0. (5) Transfer distance (downward) of the second compact component before compression (M2) M2 = F1-F2- (X2a + S2-X2b) = F1-F2-S2 + (F2-H2) R2b- ( F1-H1) R1b

(6) Transfer distance (Mn) of the component part of the n-th molded body (downward) before compression Mn = Fs-Fn- (Xsb + Sn-Xnb) However, the above (5) and (6) In the formula, Fs and Xsb are as follows. Fs: Reference height of a component part arbitrarily selected from F1 to Fn Xsb: Reference movement distance of lower punch arbitrarily selected from X1b to Xnb

As described above, even in the case of the die fixed type, the moving distance of each of the upper and lower punches corresponding to the component of the compact and the transfer of the powder are determined by the method of the present invention from the size and compression coefficient of the compact. The distance can be uniquely obtained.

As described above, according to the two embodiments of the die float method (Embodiment 1) and the die fixing method (Embodiment 2), according to the method of the present invention, in the equipment system of any specification of the die float and the die fixing. It can also be seen that it is possible to control the basic operation of the molding apparatus with a common concept.

[Embodiment 3] In this embodiment, a case will be described in which a multi-stage press is performed in a state where the neutral line (the center of pressure) in each molded part constituting the molded body is positioned on one horizontal line. I do.

When molding is performed by a multi-stage press driven by CNC control, it is possible to adjust the neutral line for each component (each molded component) by the divided molds, and to form one molded product. At
It is also possible to unify the neutral line. In the third embodiment, for example, a case where a molded body having a shape as shown in FIG. 6 is molded in a state in which a neutral line (a center of pressure) is positioned on one horizontal line will be described as an example. The molded body 10 molded in the third embodiment is the first
Molded part 1, second molded part 2,
It has a total of three molded component parts, namely, the molded component part 3 (n) of (n). When the molded body 10 is molded by the multi-stage press, the neutral line NL of each molded body constituent part 1, 2, 3 (n) is unified by satisfying the condition of the following expression, and one horizontal line is formed. On top. R1bH1 = R2bH2 + S2 = R3b (Rnb) H3
(Hn) + S3 (Sn)

That is, when the neutral line is determined so as to satisfy the condition of the above equation, the compression coefficient is determined. The portion above the neutral line of the first molded component 1 is denoted by A, the portion below the neutral line is denoted by B, the portion of the second molded component 2 above the neutral line is denoted by a, and the lower portion is denoted by b. And the third (n) molded component 3
When the portion above the neutral line NL in (n) is α and the portion below the neutral line NL is β, the above R1a, R1b, R2a,
The following relationships are established between R2b, R3a (ie, Rna), R3b (ie, Rnb) and A, B, a, b, α, β. A: B = R1a: R1b a: b = R2a: R2b α: β = R3a (Rna): R3b (Rnb)

Then, as in the first and second embodiments, the transfer position (transfer distance) of the raw material powder before pressurization is uniquely determined from the compression coefficient. Conversely, if the transfer position (transfer distance) is determined, the total compression amount by the upper and lower punches is uniquely determined, and then the moving distance of each of the upper and lower punches is uniquely determined from the compression coefficient.

In FIG. 6, the neutral line NL is used.
Are located in the compact, but as shown in FIG.
In the molded part 3 (n) of (n), the neutral line N
The present invention can be applied to a case where L is out of the range.

According to the method of the present invention, as described above, the ratio of one portion is determined so as to satisfy the conditional expression for unifying the neutral line simultaneously with the total compression amount, and the ratio of the other portion is determined. When any one of the compression coefficients is determined, the compression coefficient of the other part is uniquely determined, and further, the transfer position of the powder before compression is determined. Is uniquely determined. Therefore, according to the present invention, the basic steps of filling, transferring, and pressurizing the powder material can be performed without the need for complicated confirmation work based on advanced molding knowledge and experience as in the related art. It is possible to easily determine it from the dimensions of the body, and it is possible to drastically simplify the adjustment operation for forming a desired quality molded body.

The present invention is not limited to the above embodiment, but relates to the specific shape of the molded body, the mode of definition of each variable, etc., within the scope of the invention. It is possible to add

[0061]

As described above, according to the stepped powder molding method of the present invention (claim 1), the transfer distance of the powder and the moving distance (compression amount) of each of the upper and lower punches corresponding to the component of the compact are described. )
From the above equations, it is possible to easily determine the basic steps of filling, transferring, and pressurizing (compressing) the powder raw material from the dimensions of the molded body. This greatly simplifies the adjustment work, and makes it possible to efficiently form a molded body of a desired quality.

The step-shaped powder molding method of the present invention can be applied to both a die float method in which a die moves and a die fixing method.
In any case, the basic steps of charging, transferring, and pressurizing the powder raw material can be easily determined from the dimensions of the compact.

In the case of the die float system in which the die is moved, the lower punch of any one of a plurality of pairs of upper and lower punches is used as a fixed shaft, and the moving distance of the fixed shaft is set to 0. Thus, the moving distance of the die can be obtained.

In the case of the die fixing method in which the die is not moved, the variable XD representing the movement of the die in the case of the stepped powder molding method of claim 1 is set to 0. Thus, the moving distance of each of the upper and lower punches and the moving distance of the powder can be obtained.

Further, as in the stepped powder molding method of the fourth aspect, the above formula: R1bH1 = R2bH2 + S2 =
.. = RnbHn + Sn so that the neutral line (the center of pressure) of
When performing multi-stage pressing so that it is positioned on two horizontal lines, it suppresses distortion of the molded body and bias in the molding density that occur when the neutral line does not match,
Thus, it is possible to reliably manufacture a molded body having higher dimensional accuracy and shape accuracy.

Further, by making the compression speed ratio between the axes of a plurality of pairs of upper and lower punches constant at a certain point in time as in the stepped powder molding method according to the fifth aspect, the application of one of the upper and lower punches can be performed at a certain point in time. The pressure ratio does not differ from the pressure ratio of the other upper and lower punches, and it is possible to perform pressure at a constant pressure ratio. As a result, the powder between the upper and lower punches having a large pressing ratio is prevented from flowing between the upper and lower punches having a small pressing ratio, thereby preventing the occurrence of compression unevenness and keeping the powder density of the obtained molded body constant. It becomes possible to do.

Further, in the stepped powder molding apparatus according to the sixth aspect, the powder transfer distance and the moving distance X of each of the upper and lower punches corresponding to the component of the compact are determined based on the definition of the compact and the compression coefficient. Since it is configured to operate with a uniquely determined value as a target, the stepped shape powder molding method according to claim 1 of the present invention is surely performed to reduce distortion, reduce dimensional accuracy and shape accuracy. A high-quality molded article can be reliably manufactured.

A step-shaped powder molding apparatus according to a seventh aspect is a die-float step-shaped powder molding apparatus for moving a die. The step-shaped powder molding method of the invention of the present application (claim 2) of the die float method is surely carried out, and it is possible to reliably produce a molded product with little distortion, high dimensional accuracy and high shape accuracy. .

The step-shaped powder molding apparatus according to claim 8 is a die-fixed step-shaped powder molding apparatus that does not move a die. By using the molding apparatus having the above-described configuration, The step-shaped powder molding method of the present invention (Claim 3) of the die fixing method is surely carried out, and it is possible to reliably produce a molded body with little distortion, high dimensional accuracy and high shape accuracy. .

Further, the step-shaped powder molding apparatus according to the ninth aspect is configured such that the neutral line (the center of pressure) in each molded component can be positioned on one horizontal line. In order to suppress and prevent the distortion and uneven density of the molded body caused by the mismatch of the neutral line, it is possible to produce the molded body with less distortion, high dimensional accuracy and high shape accuracy more reliably. Becomes possible.

Further, in the step-shaped powder molding apparatus according to the tenth aspect, the compression speed ratio between the axes of the plural pairs of upper and lower punches is made constant, so that the step of the present invention (the fifth aspect). It becomes possible to carry out the powder molding method with a shape, and at a certain point in the molding process, the pressing ratio of one upper and lower punch and the pressing ratio of the other upper and lower punches are not different, and the pressing ratio is reduced. It is possible to prevent the powder between the large upper and lower punches from flowing between the upper and lower punches having a small pressing ratio, and to keep the powder density of the molded body constant.

[Brief description of the drawings]

FIG. 1 is a view showing a basic concept of a stepped powder molding method (in the case of a die float method) according to an embodiment (Embodiment 1) of the present invention.

FIGS. 2A and 2B are views showing a molded object targeted for molding in the embodiment of the present invention, wherein FIG. 2A is a perspective view, FIG.
(c) is a diagram showing the shape of a predetermined region of the molded article used for describing the present invention.

3A and 3B are diagrams showing a modified example of a compact formed by the stepped powder molding method of the present invention, wherein FIG. 3A shows a shape before compression, and FIG. 3B shows a shape after compression molding. FIG.

FIG. 4 is a diagram showing an operation when the present invention is carried out by a multi-stage press of a die float system.

FIG. 5 is a diagram showing an operation of a stepped powder molding method (in the case of a die fixing method) according to another embodiment (Embodiment 2) of the present invention.

FIG. 6 is a view showing a compact formed by a stepped powder molding method according to another embodiment (Embodiment 3) of the present invention.

FIG. 7 is a view showing a modified example of a compact formed by a stepped powder molding method according to another embodiment (Embodiment 3) of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 First compact component 1a First compact component (powder) before compression 2 Second compact component 2a Second compact component (powder) before compression 3 (n) Third compact component 3 (n) a Third compact component (powder) before compression 10 Compact D Die F1 Height of first compact component before compression (filling of powder) Height) F2 Height of second compact component before compression (filling height of powder) Fn Height of nth compact component before compression (height of powder filling) H1 Compression molding H2 Height of second molded body component after compression molding Hn Height of n-th molded body component after compression molding S2 First height after compression molding Distance from lower end of molded part to lower end of second molded part Sn Lower end of first molded part after compression molding Distance from the lower end of the n-th molded component to the lower end of the n-th molded component M2 (the downward distance) the transfer distance of the second molded component before compression Mn (downward) of the n-th molded component before compression ) Transfer distance X1a, X1b, X2a, X2b Movement distance of each punch XD Movement distance of die P1 First upper and lower punches P1 P1a Upper punch of first upper and lower punches P1b Lower punch of first upper and lower punches P2 Second upper / lower punch P2a Upper punch of second upper / lower punch P2b Lower punch of second upper / lower punch Pn nth upper / lower punch Pna Upper punch of nth upper / lower punch Pnb nth upper / lower Lower punch of punches NL, NL1, NL2, NL3 Neutral line

Claims (10)

[Claims] 1. A die filled with powder and a molding device having a plurality of pairs of upper and lower punches corresponding to the number of stages of the molded body, filling the die with powder and moving the upper and lower punches in the vertical direction. Thereby, after transferring the powder, which is filled in the die, and constituting each compact component to a compression start position by a predetermined distance (transport distance), for each compact component,
In the step-shaped powder molding method of compressing the powder by moving the corresponding upper and lower punches in the vertical direction by a predetermined distance (moving distance) and molding the powder into a stepped shape, A stepped powder molding method, wherein a moving distance of each of the upper and lower punches and the die corresponding to the molded component is a value obtained by the following equation. F1: height of the first compact component before compression F2: height of the second compact component before compression Fn: height of the n-th compact component before compression H1: after compression H2: height of the second molded body component after compression molding Hn: height of the n-th molded body component after compression molding S2: height of the nth molded body component after compression molding Distance from the lower end of the first molded component to the lower end of the second molded component Sn: From the lower end of the first molded component to the lower end of the n-th molded component after compression molding R1a: Compression coefficient by the first upper punch P1a R1b: Compression coefficient by the first lower punch P1b R2a: Compression coefficient by the second upper punch P2a R2b: Compression coefficient by the second lower punch P2b Rna: n, the compression coefficient of the upper punch Pna Rnb: Compression coefficient by the n-th upper punch Pnb X1a · 1b: First upper punch P1a and lower punch P1
x2a · 2b: second upper punch P2a and lower punch P2
xna × nb: n-th upper punch Pna and lower punch Pn
XD: Moving distance of the die M1: Transfer distance of the first molded component before compression M2: Transfer distance of the second molded component before compression Mn: n-th molding before compression Transfer distance of body constituent part Plus (+) sign: Upward movement Minus (-) sign: Downward movement: (1) Movement distance of first upper and lower punches P1 Total compression amount (total travel distance) (X
1a.1b) X1a.1b = F1-H1 Moving distance (X1a) of upper punch P1a of first upper and lower punches P1 X1a = -X1a.1b + X1a.1bR1b + XD or X1a = -X1a.1bR1a + XD First upper and lower punches X1b = X1a.1b-X1a.1bR1a + XD or X1b = X1a.1bR1b + XD (where R1a + R1b = 1) (2) Moving distance of the second upper and lower punches P2 Compression amount of the upper and lower punches P2 (total moving distance) (X
2a / 2b) X2a / 2b = F2-H2 Moving distance of upper punch P2a of second upper / lower punch P2 (X2a) X2a = -X2a / 2b + X2a / 2bR2b + XD of lower punch P2b of second upper / lower punch P2 Movement distance (X2b) X2b = X2a · 2b−X2a · 2bR2a + XD (where R2a + R2b = 1) (3) Movement distance of nth upper / lower punch Pn Total compression amount of nth upper / lower punch Pn (total movement distance) Xna · nb = Fn-Hn The moving distance (Xna) of the upper punch Pna among the nth upper and lower punches Pn Xna = -Xna.nb + Xna.nbRnb + XD The moving distance (Xnb) of the lower punch Pnb of the nth upper and lower punches Pn Xnb = Xna · nb−Xna · nbRna + XD (where Rna + Rnb = 1) (4) First compression before compression Transfer distance of body component (M1) M1 = Fs-F1- (Xsb + S1-X1b) (5) Transfer distance of second formed body component before compression (M2) M2 = Fs-F2- (Xsb + S2-X2b) (6) Transfer distance (Mn) of the n-th molded body component before compression Mn = Fs-Fn- (Xsb + Sn-Xnb) (However, in (4) to (6), any of Fs: F1 to Fn Xsb: reference movement distance of lower punch arbitrarily selected from X1b to Xnb) 2. An arbitrary one of the plurality of pairs of upper and lower punches.
The lower punch of the shaft is a fixed shaft, and the moving distance of the fixed shaft is 0.
The step-shaped powder molding method according to claim 1, wherein: 3. The step-shaped powder molding method according to claim 1, wherein the die is a fixed shaft, and the moving distance of the fixed shaft is zero. 4. The method according to claim 1, wherein a neutral line (a center of pressure) of each component of the molded body is positioned on one horizontal line by satisfying a condition of the following expression. 3. The step-shaped powder molding method according to any one of the above items 3. R1bH1 = R2bH2 + S2 =... = RnbHn + S
n 5. The stepped powder molding method according to claim 1, wherein the compression speed ratio between the axes of the plural pairs of upper and lower punches is made constant. 6. A configuration in which each compact is filled with a die for compressing powder, and a plurality of pairs of upper and lower punches corresponding to the number of stages of the compact, and the upper and lower punches are moved up and down. After the powder constituting the portion has been transported a predetermined distance (transport distance) to the compression start position, the upper and lower punches corresponding to the respective molded body component portions move up and down a predetermined distance (movement distance). A step-shaped powder molding apparatus configured so that the powder is compressed and is formed into a stepped shape having a thickness different in a compression direction, wherein a transfer distance of the powder, Wherein the moving distance of each of the upper and lower punches and the die corresponding to the above is set to a value determined by the following equation. F1: height of the first compact component before compression F2: height of the second compact component before compression Fn: height of the n-th compact component before compression H1: after compression H2: height of the second molded body component after compression molding Hn: height of the n-th molded body component after compression molding S2: height of the nth molded body component after compression molding Distance from the lower end of the first molded component to the lower end of the second molded component Sn: From the lower end of the first molded component to the lower end of the n-th molded component after compression molding R1a: Compression coefficient by the first upper punch P1a R1b: Compression coefficient by the first lower punch P1b R2a: Compression coefficient by the second upper punch P2a R2b: Compression coefficient by the second lower punch P2b Rna: n, the compression coefficient of the upper punch Pna Rnb: Compression coefficient by the n-th upper punch Pnb X1a · 1b: First upper punch P1a and lower punch P1
x2a · 2b: second upper punch P2a and lower punch P2
xna × nb: n-th upper punch Pna and lower punch Pn
XD: Moving distance of the die M1: Transfer distance of the first molded component before compression M2: Transfer distance of the second molded component before compression Mn: n-th molding before compression Transfer distance of body constituent part Plus (+) sign: Upward movement Minus (-) sign: Downward movement: (1) Movement distance of first upper and lower punches P1 Total compression amount (total travel distance) (X
1a.1b) X1a.1b = F1-H1 Moving distance (X1a) of upper punch P1a of first upper and lower punches P1 X1a = -X1a.1b + X1a.1bR1b + XD or X1a = -X1a.1bR1a + XD First upper and lower punches X1b = X1a.1b-X1a.1bR1a + XD or X1b = X1a.1bR1b + XD (where R1a + R1b = 1) (2) Moving distance of the second upper and lower punches P2 Compression amount of the upper and lower punches P2 (total moving distance) (X
2a / 2b) X2a / 2b = F2-H2 Moving distance of upper punch P2a of second upper / lower punch P2 (X2a) X2a = -X2a / 2b + X2a / 2bR2b + XD of lower punch P2b of second upper / lower punch P2 Movement distance (X2b) X2b = X2a · 2b−X2a · 2bR2a + XD (where R2a + R2b = 1) (3) Movement distance of nth upper / lower punch Pn Total compression amount of nth upper / lower punch Pn (total movement distance) Xna · nb = Fn-Hn The moving distance (Xna) of the upper punch Pna among the nth upper and lower punches Pn Xna = -Xna.nb + Xna.nbRnb + XD The moving distance (Xnb) of the lower punch Pnb of the nth upper and lower punches Pn Xnb = Xna · nb−Xna · nbRna + XD (where Rna + Rnb = 1) (4) First compression before compression Transfer distance of body component (M1) M1 = Fs-F1- (Xsb + S1-X1b) (5) Transfer distance of second formed body component before compression (M2) M2 = Fs-F2- (Xsb + S2-X2b) (6) Transfer distance (Mn) of the n-th molded body component before compression Mn = Fs-Fn- (Xsb + Sn-Xnb) (However, in (4) to (6), any of Fs: F1 to Fn Xsb: reference movement distance of lower punch arbitrarily selected from X1b to Xnb) 7. An arbitrary one of the plurality of pairs of upper and lower punches.
7. A step-shaped powder molding apparatus in which a lower punch of a shaft is configured as a fixed shaft, wherein the moving distance of the fixed shaft is set to 0. Powder molding equipment. 8. The step-shaped powder molding apparatus in which the die is configured as a fixed shaft, wherein a moving distance of the fixed shaft is set to 0. Stepped powder molding equipment. 9. The apparatus according to claim 6, wherein the neutral line (the center of pressure) of each component of the molded body is positioned on one horizontal line by satisfying the following condition. The step-shaped powder molding apparatus according to any one of claims 1 to 8. R1bH1 = R2bH2 + S2 =... = RnbHn + S
n 10. The compression speed ratio between the axes of a plurality of pairs of upper and lower punches is made constant.
The step-shaped powder molding apparatus according to any one of the above.