TW201408404A - Device for high-density molding and method for high-density molding of mixed powder - Google Patents

Abstract

In the present invention, a mixed powder (100) filling the inside of a container cavity (24) is transferred into the cavity of a first die, a first applied pressure is applied to the mixed powder (100) in the first die (31), molding an intermediate powder compact (110), the post-molding first die (31) and intermediate powder compact (110) are heated, causing the intermediate powder compact (110) to be warmed to the melting-point-equivalent temperature of a lubricant, the post-warming intermediate powder compact (110) is transferred into the cavity of a second die (61) and a second applied pressure is applied, thus molding a high-density completed powder compact.

Description

High-density forming method of mixed powder and high-density forming device

The present invention relates to a high-density molding method and a high-density molding apparatus which can form a high-density (for example, 7.75 g/cm ³ ) powder compact by secondary pressurization of a mixed powder.

Generally, the powder metallurgy technique is to pressurize (compress) a metal powder to form a powder compact of a predetermined shape, and then heat the powder compact to a temperature near the melting point of the metal powder and promote bonding (solidification) between the particles. A series of techniques for sintering. As a result, it is possible to manufacture mechanical components having high shape and high dimensional accuracy at low cost.

With the demand for smaller and lighter weight of mechanical components, it is required to increase the mechanical strength of the powder compact. On the other hand, if the powder compact is exposed to a high temperature atmosphere, the magnetic properties are lowered. Therefore, when the powder compact for magnetic core is actually produced, the subsequent high temperature treatment (sintering treatment) may be omitted. In other words, a method of improving mechanical strength even without performing high temperature treatment (sintering treatment) is being explored.

Here, it has been suggested that the mechanical strength is greatly increased (hyperbolic type) as the density of the powder compact increases. As a representative high As a method of densification, a method of mixing a lubricant in a metal powder to reduce frictional resistance and press-forming is proposed (for example, Patent Document 1). Usually, about 1% by weight (1% by weight) of the lubricant-forming mixed powder is mixed in the base metal powder, and the mixed powder is subjected to press forming. Others have proposed a number of programs aimed at further increasing the density. These solutions are broadly divided into processes that improve the lubricant itself and improve the press forming and sintering processes.

As a solution belonging to the former, a carbon molecular composite in which spherical carbon molecules and platy carbon molecules are combined may be mentioned (for example, Patent Document 2); a lubricant having a penetration of 0.3 mm to 10 mm at 25 ° C is used. Solution (for example, Patent Document 3). These solutions are all solutions for reducing the frictional resistance between the metal powders and between the metal powder and the mold.

As a solution belonging to the latter, there are known warm-forming and sintering powder metallurgy methods (Patent Document 4), pre-warm forming powder metallurgy method (Patent Document 5), and secondary press-secondary sintering powder. Metallurgical methods (for example, Patent Document 6) and primary forming-sintering powder metallurgy methods (Patent Document 7).

The initial warm forming and sintering powder metallurgy method is to pre-heat a metal powder mixed with a solid lubricant and a liquid lubricant to melt a part (or all) of the lubricant and disperse the lubricant between the particles. The method reduces the frictional resistance between particles and between the particles and the mold to improve the formability; the pre-warm forming powder metallurgy method with convenient operation is provided with a primary forming step to mix the powder before the warm forming step. A low-density (for example, a density ratio of less than 76%) primary molded body which is facilitated by a press forming operation, which is lower than a low temperature which causes a blue brittleness temperature of the primary formed body In the state, the primary molded body is once disintegrated and subjected to a secondary forming step to obtain a secondary molded body (powder compact). The secondary stamping-secondary sintering powder metallurgy method is a method of pressurizing an iron powder mixture containing an alloying component in a mold to form a primary compressed body, and pre-sintering the compressed body (powder compact) at 870 ° C for 5 minutes and A pre-sintered body is produced, and a pre-sintered body which has been twice pressed is formed by pressurizing the pre-sintered body, and thereafter, a pre-sintered body which has been twice pressed is sintered at 1000 ° C for 5 minutes to form a sintered component. The last forming-sintering powder metallurgy method is to preheat the mold in advance and electrically attach the inner surface to the lubricant in advance, and then fill the mold with the heated iron-based powder mixture (iron-based powder + lubricant powder) to define The iron-based powder molded body is formed by temperature press molding, and then the iron-based powder molded body is subjected to a sintering treatment to further perform bright quenching, and thereafter a tempering treatment is performed to produce an iron-based sintered body.

As described above, the density of the powder compact is up to about 7.4 g/cm ³ (94% of true density) using any improvement method related to the lubricant or the press forming and sintering process. The mechanical strength is not enough. Further, when the sintering treatment (high temperature atmosphere) is performed, since the oxidation is increased with temperature and time, the lubricant in the powder particle-coated state is burned to generate a residue, and the quality of the powder compact after the press molding is lowered, so that the actual production is performed. The density at the time became 7.3 g/cm ³ or less. Moreover, any improvement method is complicated and inevitably becomes costly. The operation is also troublesome and the practicality is poor.

In particular, in consideration of a core (magnetic core) for producing an electromagnetic device (motor, transformer, etc.) from a powder compact, it is often pointed out that such a density (7.3 g/cm ³ or less) is far from satisfactory. In order to reduce the loss (iron loss, hysteresis loss) and increase the magnetic flux density, it is necessary to further increase the density of the powder compact. For example, from the speech of the Autumn Powder Powder Metallurgy Association Autumn Conference (Toyota Co., Ltd.) The Central Research Institute provides) it is clear at a glance. The core density, for example, even 7.5 g/cm ³ , is pointed out in practical applications not only in magnetic properties but also in mechanical strength.

Regarding the production of the powder compact for the core, a powder metallurgy method of secondary forming-primary sintering (primary annealing) has been proposed (for example, Patent Document 8). The powder metallurgy method of this patent application is based on the technical content that if a coating containing a ruthenium resin and a pigment is formed in advance on the surface of the magnetic metal powder, the insulation property is not lowered even after high-temperature treatment. That is, the method for producing a dust core is characterized in that a magnetic powder coated with a coating layer containing a bismuth resin and a pigment is preformed into a preform, and the preform is subjected to a heat treatment forming heat treatment at a temperature of 500 ° C or higher. Next, the heat-treated body is subjected to compression molding. When the temperature is 500 ° C or lower, the film is likely to be broken during the subsequent compression molding. When the temperature is 1000 ° C or higher, the insulation property is decomposed and burned. Therefore, the temperature for the heat treatment is set in the range of 500 ° C to 1000 ° C. From the viewpoint of preventing oxidation of the preform, the high temperature treatment can be carried out in a vacuum, an inert gas atmosphere or a reducing gas atmosphere. Therefore, it is described that a dust core having a true density of 98% (7.7 g/cm ³ ) can be produced.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 1-219101

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2009-280908

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2010-37632

[Patent Document 4] Japanese Patent Laid-Open No. Hei 2-156002

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2000-87104

[Patent Document 6] Japanese Patent Laid-Open No. 4-231404

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2001-181701

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2002-343657

However, the secondary forming-primary sintering powder metallurgy method (Patent Document 8) is more complicated, individualized, and difficult to implement and implement than the methods of other patent applications, resulting in a substantial increase in manufacturing costs. Further, the preform must be heat-treated at 500 ° C or higher. In order to prevent deterioration of the quality of the powder core, it must be carried out in a special atmosphere, so it is not suitable for mass production. In particular, since the glass material is deteriorated and melted, it is not suitable for the case of a magnetic metal powder coated with a glass coating.

In addition, in any of the above-described methods and apparatuses (Patent Documents 1 to 8), it is described that the sintering treatment can be performed in a relatively high-temperature atmosphere, but the details of the pressure forming step are not clear. There are no records related to new improvements in the analysis of the specifications and functions of the press forming machine, the relationship between the applied pressure and the density, or the limits thereof.

Therefore, a higher mechanical strength is required from the accompanying small size and light weight. From a point of view, it is imperative to develop a method and apparatus that can reliably and stably produce high-density powder compacts (especially high-density powder compacts for magnetic cores) at low cost.

An object of the present invention is to provide a high-density forming method of a mixed powder and a high-density forming apparatus which can produce a high-density powder compact by performing a secondary press forming before and after heating of the mixed powder and can greatly reduce the manufacturing cost. .

According to the convention of manufacturing a powder compact by the sintering metallurgy technique, it is necessary to carry out a sintering treatment on a pressure-molded powder compact under a high temperature atmosphere (for example, 800 ° C or higher). However, high-temperature treatment for sintering not only consumes a large amount of energy, but also has a large cost burden, and it also has great harm in protecting the global environment, and needs to be reconsidered.

In the conventional press forming treatment, the mixed powder is established in a specific form, and it is considered to be a mechanical treatment in the previous stage (preparation) of the high-temperature sintering treatment, and this has been treated as such. However, the current state of the art is to omit high-temperature processing for sintering only when manufacturing a powder compact for a core for an electromagnetic device (motor, transformer, etc.). This is to avoid adverse effects (deterioration of magnetic properties) after high temperature treatment. That is, it is forced to accept the lack of mechanical strength. The lack of mechanical strength is due to the problem of density, so the magnetic properties are of course insufficient.

Here, if high-temperature forming of the powder compact can be achieved by only the press forming treatment without performing the high-temperature sintering treatment, it should be able to Improve the utilization and popularization of powder compacts in the industry. The present invention has been created based on analysis, and is capable of satisfying the efficiency of filling of mixed powders suitable for actual production and miniaturization and weight reduction of first and second molds, etc., which is the effectiveness of lubricants during pressurization. , the compression limit of the lubricant powder, the space occupancy of the lubricant powder in the mixed powder, the spatial arrangement state of the base metal powder and the lubricant powder, and the characteristics thereof and the final disposal state of the lubricant, and general Analysis of the characteristics of the press molding machine, the compression limit, and the effect of the density of the powder compact on strength or magnetic properties.

That is, the present invention transfers the mixed powder that has been filled into the container cavity into the first mold, maintains the powder state of the lubricant in the first mold, and forms the mixed powder intermediate compression body through the first pressing step, followed by lubrication by heating. The agent is liquefied to change the lubricating mode in the intermediate compressed body of the mixed powder, and thereafter, the mixed compact intermediate compressed body heated and heated is transferred into the second mold and subjected to the second pressurizing step to produce a high density close to the true density. Complete the powder compact. In other words, it relates to a new powder metallurgy technology (secondary press forming before and after the lubricant liquefaction step) which is invented by the conventional sintering metallurgy technology which requires high-temperature sintering treatment, and provides high density which can be stably and cost-effectively manufactured. An epoch-making method and apparatus for powder compacts.

(1) Specifically, a high-density forming method of a mixed powder according to an embodiment of the present invention, characterized in that a mixed powder is filled in a container cavity, the mixed powder being a base metal powder and a low melting point lubrication a mixture of powders that transfer the mixed powder in the container cavity to the cavity of the first mold that has been positioned corresponding to the cavity, toward the cavity of the first mold The first mixed pressure forming mixed powder intermediate compressed body is applied to the inner mixed powder, and the first molded mold and the mixed powder intermediate compressed body are heated to raise the temperature of the mixed powder intermediate compressed body to a temperature corresponding to the melting point of the lubricant, and the temperature is raised. The mixed powder intermediate compression body is positioned corresponding to the second mold together with the first mold, and the mixed powder intermediate compression body in the cavity of the first mold is transferred to the cavity of the second mold corresponding to the positioning of the first mold, to the second The mixed powder intermediate compressed body in the cavity of the mold is subjected to a second pressurization to form a high-density mixed powder to complete the compressed body.

Further, in the invention of the above (1), the melting point of the lubricant powder may be a low melting point, and the low melting point may be in a temperature range of 90 ° C to 190 ° C.

Further, in the invention of the above (1) or (2), the second mold may be preheated to a temperature corresponding to the melting point of the lubricant before receiving the mixed powder intermediate compressed body.

Further, in the invention of the above (1) or (2), the mold may be preheated after the completion of the molding of the mixed powder intermediate compression body.

Further, (5) In the invention of (1) or (2) above, the second pressing force may be equal to the first pressing force.

Further, (6) a high-density forming apparatus for a mixed powder according to a second embodiment of the present invention, comprising: a mixed powder feeder capable of filling a mixed powder with a container chamber positioned at a mixed powder filling position, The mixed powder is a mixture of a base metal powder and a low melting point lubricant powder; the mixed powder transfer device transfers the mixed powder in the container cavity to the cavity of the first mold that has been positioned corresponding to the container; the first press molding machine Applying a first pressure forming mixed powder intermediate compressed body to the mixed powder in the cavity of the first mold by the first punch; heating the heating machine for heating and heating the temperature rising position to position the first mold and the mixed powder intermediate compression body And increasing the temperature of the mixed powder intermediate compression body to a temperature corresponding to the melting point of the lubricant; the intermediate powder compact transfer device transfers the mixed powder intermediate compression body in the cavity of the first mold to the position that has been positioned at the transfer transition position In the second mold; the second press molding machine applies a second pressure forming high density to the mixed powder intermediate compression body of the second mold that has been positioned at the position where the powder compact is formed at the second blank forming machine The mixed powder completes the compressed body; and the product discharge device discharges the mixed powder in the cavity of the second mold at the discharge position of the product to complete the compressed body.

Further, (7) in the invention of (6) above, it may be provided that: the first mold transfer device is configured to transport the first mold and can be positioned corresponding to the container that has been positioned at the mixed powder filling position; before heating The powder compact conveying device is configured to convey the first mold from the intermediate powder compact forming position and to position it corresponding to the heating temperature rising position; after heating, the powder green conveying device is arranged to be stored from the heating temperature rising position The first mold of the mixed powder intermediate compression body is conveyed and positionable corresponding to the transfer transition position; the second mold transfer device is configured to be capable of accommodating the second mold containing the mixed powder intermediate compression body from the transfer transition position Transmitting and positioning corresponding to the completion of the powder compact forming position; completing the powder compact conveying device, configured to transfer the second mold containing the mixed powder to complete the compressed body from the completed powder compact forming position and Positioning corresponding to the product discharge position; and the second mold returning conveyor, configured to be discharged from the product The position will accommodate the second mold transfer of the mixed powder to complete the compression body and position it corresponding to the receiving transition position.

Further, in the invention of the above (6), the mixed powder filling position, the heating temperature rising position, and the transfer transition position are disposed on the first circular trajectory centered on the first axis, and the transfer position is completed, and the powder is completed. The compact forming position and the product discharge position are disposed on a second circular track centered on the second axis, and the first mold transfer device, the pre-heating powder green transfer device, and the heated powder green transfer device are used first The first rotary table is pivotally centered, and the second mold transfer device, the completed powder green transfer device, and the second mold return transfer device are constructed using a second rotary table that is rotatable about a second axis.

(9) In the invention of (6) or (7) above, the first preheating device for preheating the first mold may be further provided.

(10) In the invention of (6) or (7) above, the second preheating device for preheating the second mold may be further provided.

According to the invention of the above (1), it is possible to stably produce a high-density powder compact, and it is possible to greatly reduce the manufacturing cost, and it is possible to achieve high efficiency in filling work of the mixed powder corresponding to actual production, and first and second molds, and the like. Small and lightweight.

According to the invention of the above (2), it is possible to ensure sufficient lubrication of the lubricant in the first pressurizing step. Moreover, the types of lubricants are more selective.

According to the invention of the above (3), since the fluidity of the melted lubricant in all directions during the second press forming can be further improved, the space between the particles and the second mold can be greatly reduced and maintained in addition to the base metal particles. Frictional resistance.

According to the invention of the above (4), the manufacturing cycle can be shortened, and the manufacturing cycle includes the temperature rise time of the mixed powder intermediate compression body.

According to the invention of the above (5), the implementation in the press forming step and the treatment thereof are easy, and it is possible to indirectly contribute to further reducing the manufacturing cost of the powder compact.

Further, according to the invention of the above (6), the high-density molding method of the mixed powder of the above (1) to (5) can be reliably carried out, and it can be easily realized at low cost, and the operation is simple.

Further, according to the invention of the above (7), the simplification of the apparatus and the rapid and smooth transfer of the powder compact can be achieved as compared with the case of the invention of the above (6).

Further, according to the invention of the above (8), the simplification of the apparatus can be achieved as compared with the case of the invention of the above (7). This can further simplify the production line and make handling easier.

According to the invention of the above (9), the manufacturing cycle can be shortened, and the manufacturing cycle includes the temperature rise time of the mixed powder intermediate compression body.

According to the invention of the above (10), since the fluidity of the dissolved lubricant in all directions during the second press forming can be further improved, the space between the particles and the second mold can be greatly reduced and maintained in addition to the base metal particles. Frictional resistance.

Further, the configuration and effects of the present invention other than the above can be understood from the following description.

1‧‧‧High-density forming device

10‧‧‧Mixed powder feeder

20‧‧‧ container installation

23‧‧‧ Container

30‧‧‧First Press Forming Machine

31‧‧‧First mould

34‧‧‧First preheating device

37‧‧‧Under punch (mixed powder transfer device)

40‧‧‧heating machine

50‧‧‧ Launched rod (intermediate powder compact transfer device)

60‧‧‧Second pressure forming machine

61‧‧‧Second mold

64‧‧‧Second preheating device

70‧‧‧Workpiece discharge device

80‧‧‧First rotary table (first mold transfer device, pre-heated powder green transfer device, heated powder green transfer device)

90‧‧‧Second rotary table (second mold transfer device, completed powder compact transfer device, second mold return transfer device)

100‧‧‧ mixed powder

110‧‧‧Intermediate powder compact (mixed powder intermediate compression body)

120‧‧‧ Complete the powder compact (mixed powder to complete the compression).

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view for explaining a high-density molding method related to the present invention.

Fig. 2 is a top view for explaining a high-density molding apparatus and an operation according to a first embodiment of the present invention.

Fig. 3 is a longitudinal cross-sectional view for explaining an operation from the mixed powder filling operation to the positioning of the intermediate powder compact corresponding to the transfer transition position in the first embodiment of the present invention.

Fig. 4 is a longitudinal cross-sectional view for explaining an operation from the receiving operation of the intermediate green compact to the discharge of the powder compact (product) at the product discharge position in the first embodiment of the present invention.

Fig. 5 is a graph for explaining the relationship between the pressing force and the density obtained by the pressing force according to the first embodiment of the present invention, and the characteristic A indicated by a broken line indicates the forming state in the first mold, which is indicated by a solid line. Characteristic B indicates the state of formation in the second mold.

Fig. 6A is a perspective view showing the appearance of a completed powder compact (intermediate powder compact) according to the first embodiment of the present invention, and has a circular shape.

Fig. 6B is a perspective view showing the appearance of a completed powder compact (intermediate powder compact) according to the first embodiment of the present invention, which has a cylindrical shape.

Fig. 6C is an external perspective view for explaining the completed powder compact (intermediate powder compact) according to the first embodiment of the present invention, and has an elongated circular axis shape.

Fig. 6D is a perspective view showing the appearance of a completed powder compact (intermediate powder compact) according to the first embodiment of the present invention, and has a disk shape.

Fig. 6E is a perspective view showing the appearance of a completed powder compact (intermediate powder compact) according to the first embodiment of the present invention, which has a complicated shape.

FIG. 7 is a longitudinal cross-sectional view for explaining an operation from the mixed powder filling operation of the high-density molding apparatus according to the second embodiment of the present invention to the positioning of the intermediate powder compact corresponding to the transfer transition position.

8 is a longitudinal cross-sectional view for explaining an operation from the receiving operation of the intermediate powder compact according to the second embodiment of the present invention to the completion of discharge of the powder compact (product) at the product discharge position.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)

As shown in FIGS. 1 to 6E, the high-density molding apparatus 1 of the mixed powder has a mixed powder feeder 10, a container 23, a mixed powder transfer device (lower punch 37), a first press molding machine 30, and heating and heating. The machine 40, the intermediate powder compact transfer device (the squeeze bar 50), the second press molding machine 60, and the product discharge device 70 are provided as a high-density forming method capable of stabilizing and surely implementing the mixed powder, the mixed powder The high-density molding method is composed of the following steps: a mixed powder filling step (PR1) in which the mixed powder 100 shown in FIG. 1(A) is filled into the container 23; the mixed powder 100 is to be mixed. The mixed powder transfer step (PR2) transferred to the first mold 31; applying a first pressurizing force P1 to the mixed powder 100 in the first mold 31 to form a mixed powder intermediate compressed body (sometimes referred to as an intermediate powder compact 110) Intermediate powder compact forming step (PR3); heating the formed intermediate powder compact 110 to positively raise its temperature to a heating and heating step (PR4) corresponding to the melting point temperature of the lubricant powder; and pressing the heated intermediate powder The blank 110 is transferred to the intermediate powder green transfer step (PR5) in the second mold 61; a second pressing force P2 is applied to the intermediate powder compact 110 in the second mold 61 to form a high-density mixed powder to complete the compression body (sometimes also The completed powder compact forming step (PR6) and the product discharging step (PR7) are completed to complete the powder compact 120.

Further, in this embodiment, a first mold transfer device for conveying the first mold 31 to the mixed powder filling position (intermediate powder compact forming position) Z11, the heating temperature increasing position Z12, and the transfer transition position Z13 is provided (No. a mold return conveying device 81, a pre-heating powder green conveying device 82, and a heated powder green conveying device 83, and provided for conveying the second mold 61 to the transfer transition position Z13 (accepting the transition position Z21), completing the powder The second mold transfer device 91 of the green compact forming position Z22 and the product discharge position Z23, the completed powder compact transfer device 92, and the second mold return transfer device 93 ensure the rapid and smooth transfer of the mold.

Further, the first mold transfer device 81, the pre-heating powder green transfer device 82, and the heated powder green transfer device 83 are disposed to be integrally formed using the first rotary table 80 of FIG. 2, and the second mold transfer device 91 is disposed. The completed powder compact conveying device 92 and the second mold return conveying device 93 are arranged to be integrally formed using the second rotary table 90 of FIG. The final realization of the simplification of the composition.

The mixed powder 100 in the specification of the present application means a mixture of a base metal powder and a low melting point lubricant powder. Further, as the base metal powder, there is a case where only one main metal powder is used, and a main metal powder and a powder of one or more alloy components are mixed therein, but any case can be applied. The low melting point means a temperature (melting point) at which the temperature (melting point) is significantly lower than the melting point (temperature) of the base metal powder, and the temperature at which the base metal powder is oxidized can be greatly suppressed.

In Fig. 3 showing the high-density forming apparatus 1, the mixed powder feeder 10 disposed on the upstream side mixed powder filling position Z11 of the high-density forming operation line is a device for filling the mixed powder 100 into the container 23, and the drawing is carried out. The mixed powder filling step (PR1) of 1 (A) is used. The function and the quantitative supply function of the mixed powder 100 having a predetermined fixed amount can be selectively transferred back and forth between the initial position (the position not shown in the left direction in FIGS. 2 and 3) and the container device 20.

The container device 20 is composed of a hollow cylindrical body 21 having a stopper 22 at its upper portion, a container 23 having a stopper 25 at its lower portion and a container chamber 24 having a hollow cylindrical shape at its center, and a spring 26 biasing the container 23 upward. Positioned on the mixed powder filling position Z11. A lower punch 37 constituting a part of the first press molding machine 30 (first mold 31) is slidably fitted to the container cavity 24, and the filling of the filled mixed powder 100 is determined by the relative position of the container 23 in the vertical direction. the amount. The container 23 is held at the initial position in the up-and-down direction shown in Fig. 3(A) by the urging force of the spring 26 in a state where the stopper 25 is restricted by the stopper 22.

The mixed powder 100 is first filled into the container 23 (the container cavity 24) as compared with the case where the mixed powder 100 is directly filled into the cavity 33 of the mold 32 constituting the first mold 31 of the first press molding machine 30. After being transferred into the cavity 33, a large amount of the mixed powder 100 can be filled in a slightly compressed state by pre-compression. Further, it is easy to convey the first mold 31 (the mold 32) together with the mixed powder intermediate compression body 110 to the transfer transition position (heating temperature rising position Z12). The structure can be greatly simplified as compared with the conventional example in which only the workpiece (powder compact) is taken out from the first mold 31 and transferred into the second mold. The pre-pressing can be carried out by the action of the mixed powder transfer device (lower punch 37) which will be described later.

Since it is very important to uniformly and sufficiently fill the mixed powder 100 from the container 23 into each of the first molds 31 (the molds 32), the mixed powder 100 must be in a loose state. That is, the form of the internal space (cavity 33) of the first mold 31 (mold 32) is set to correspond to the form of the product. Even if the shape of the product is complicated or has a narrow portion, in order to secure the dimensional accuracy of the intermediate powder compact 110, it is preferable to avoid uneven filling or insufficient filling.

The form (size, state) of the powder compact 120 (intermediate powder compact 110) is not particularly limited, but is shown, for example, in FIGS. 6A to 6E. Fig. 6A shows a ring shape, Fig. 6B shows a cylindrical shape, Fig. 6C shows an elongated circular shaft shape, Fig. 6D shows a circular plate shape, and Fig. 6E shows a complicated shape. The intermediate powder compact 110 (completed powder compact 120) of this embodiment is a cylindrical shape as shown in Figs. 3 and 6B, and the internal space (cavity 33) of the first mold 31 is shaped into a shape corresponding thereto.

Here, the lubricant for reducing the frictional resistance between the base metal particles and the frictional resistance between the base metal powder and the inner surface of the mold, which is a part of the base metal powder, is selected as a solid (very small granular shape) which is in a loose state at normal temperature. For example, when a liquid lubricant is used, the mixed powder 100 has a high viscosity and low fluidity, and cannot be uniformly filled or sufficiently filled.

Next, in the intermediate powder compact forming in which the first pressing force P1 is applied and applied in the first mold 31 (cavity 33) at normal temperature, the lubricant must be stably maintained in a solid state to maintain a predetermined lubricating action. Even if the temperature rises slightly by the pressurization of the first applied pressure P1, it should be stably maintained.

On the other hand, from the viewpoint of selectively performing the relationship between the heating and heating step (PR4) of FIG. 1 and the oxidation of the base metal powder after the intermediate powder compact is formed, the melting point of the lubricant powder is required to be compared with the melting point of the base metal powder. Set to a very low melting point (low melting point).

The melting point of the lubricant powder is selected to be a low melting point, which is, for example, in the range of 90 ° C to 190 ° C. The lower temperature (90 ° C) is an upper limit temperature (80 ° C) which is lower than the temperature (for example, 70 ° C to 80 ° C) which is estimated to be less than the temperature rise during the intermediate powder compact molding. There is a margin value (for example, 90 ° C), and then the melting point of other metal soaps (for example, 110 ° C) is selected. That is, the risk of the lubricating oil powder melting (liquefying) and flowing out during the press forming of the intermediate powder compact 110 is completely eliminated.

The upper side temperature (190 ° C) is selected to be the minimum value from the viewpoint of the selective increase in the type of the lubricant powder, especially in the heating and heating step. The maximum value is seen from the viewpoint of suppressing oxidation of the base metal powder. That is, it is desirable to understand that the lower temperature and the upper temperature of the temperature range (for example, 90 ° C to 190 ° C) are not limit values but boundary values.

Therefore, many substances (zinc stearate, magnesium stearate, etc.) which are metal soaps can be selectively used as the lubricant powder. In addition, since the lubricant must be in a powder state, a viscous liquid such as zinc octoate or the like cannot be used.

In this embodiment, zinc stearate powder having a melting point of 120 ° C is used as the lubricant powder. Further, in the present invention, the invention of Patent Document 7 is a method in which a lubricant having a temperature lower than the mold temperature at the time of press molding (melting point) is used, and the lubricant is first melted (liquefied) and subjected to press molding. When the melted lubricant flows out before the completion of the intermediate powder compact 110, the portion where the lubrication is insufficient in the middle is likely to occur, so that sufficient press forming cannot be performed reliably and stably.

The amount of the lubricant powder is set to a value selected according to empirical rules in experimental research and actual production. In the relationship of the intermediate powder compact forming step (PR3) according to this embodiment, the amount of the lubricant powder is set to be 0.23 wt% to 0.08 wt% of the total amount of the mixed powder. 0.08 wt% is the lower limit value of the lubricating action until the intermediate powder compact 110 is formed, and 0.23 wt% is necessary to obtain a desired compression ratio when the mixed powder 100 is changed to the intermediate powder compact 110. Limit.

Next, the amount of the lubricant powder in actual production should be set to a value that ensures the true density ratio of the intermediate powder compact 110 formed by applying the first pressing force P1 in the first mold 31 and the sweating phenomenon in the second mold. Amount . At this time, it is necessary to take into consideration the occurrence of dripping (drip phenomenon) which causes the liquefied lubricant to leak out from the mold to the outside to cause deterioration of the working environment.

In this embodiment, since the value of the true density ratio (ratio of 100% to true density) of the intermediate powder compact 110 is 80% to 90%, the amount of the lubricant powder is set to 0.2 wt% to 0.1 wt. %. The upper limit side value (0.2 wt%) is determined from the viewpoint of preventing the occurrence of dripping, and the lower limit side value (0.1 wt%) is determined from the viewpoint of avoiding occurrence of insufficient or surplus and only occurrence of necessary sweating. Compared with the above-mentioned conventional proposal (1 wt%), the amount is only a small amount, but the industrial availability can be greatly improved.

Preventing the occurrence of dripping is extremely important for actual production. In the planning or research stage, there is a tendency to mix a very large amount of lubricant due to an insufficient amount of lubricant in order to reduce the friction at the time of pressurization. For example, there is a case where an excessive amount of lubricant liquefies and flows out from the start of a trial and error phase in which a high density of more than 7.3 g/cm ³ can be produced. Not even aware of the phenomenon of dripping. That is, the dripping of the liquefied lubricant causes an increase in the cost of the lubricant, which causes a decrease in production efficiency due to deterioration of the working environment or an increase in the burden on the operator. If it is not solved, it is not only practical but also difficult to spread.

The case where the 0.2% by weight of the mixed powder 100 is compressed to the intermediate powder compact 110 having a true density ratio of 80% is an intermediate powder pressure once the lubricant powder is actively heated to a melting point equivalent temperature in the heating and heating step (PR3). The powder lubricant dispersed in the blank 110 is melted to fill the pores between the metal powder particles, and then uniformly oozes (sprays) on the surface of the intermediate powder compact 110 through the liquid lubricant between the metal powder particles. Inducing sweating Elephant. When the second pressing force P2 is applied to the intermediate powder compact 110 in the second mold for compression, the frictional resistance between the base metal powder and the inner wall of the chamber is greatly reduced.

Also, the case where the 0.1 wt% of the mixed powder 100 is compressed to the intermediate powder compact 110 having a true density ratio of 90%, and the mixed powder 100 in the range of more than 0.1 wt% and less than 0.2 wt% is compressed to a true density ratio In the case of the intermediate powder compact 110 having a value of less than 90% and exceeding 80%, sweating can also be observed. It also prevents dripping.

Therefore, it is possible to form a green compact (for example, a magnetic core) which satisfies magnetic properties and mechanical strength at a high density, and also eliminates the fear of damage to the mold. Moreover, the consumption of the lubricant can be greatly reduced, so that the liquid lubricant no longer leaks out of the mold, improving the working environment. Overall, the industrial applicability can be remarkably improved because the production efficiency can be improved and the manufacturing cost of the powder compact can be reduced.

Meanwhile, any of the above conventional methods and apparatuses (Patent Documents 1 to 8) has no knowledge of the relationship between the content ratio of the lubricant and the compression ratio of the mixed powder 100, the dripping phenomenon caused by the amount of the lubricant, and the sweating phenomenon. In particular, even in the thermoforming powder metallurgy method (Patent Document 5), it can be understood that the point of the primary molded body having a density ratio of less than 76% is formed for the convenience of handling. However, the technical basis and practical matters related to high-density forming are not disclosed. In addition, from the point of view that the primary formed body (intermediate powder compact 120) is crushed and reshaped into a secondary formed body (completed powder compact), it can only be denied that it is accumulated by primary forming and secondary forming. High density Technical thinking.

The first press molding machine 30 is a device that applies the first pressing force P1 to the mixed powder 100 supplied into the first mold 31 (cavity 33) by using the mixed powder feeder 10 to form the mixed powder intermediate compressed body 110. It is a stamping machine construction.

In FIGS. 3(A) and 3(B), the first mold 31 is composed of a lower mold (mold 32, lower punch 37) on the table side and an upper mold (upper punch 36) on the slider (not shown) side. Composition. The cavity 33 of the mold 32 is provided in a shape (hollow cylindrical shape) corresponding to the form (cylindrical shape) of the intermediate powder compact 110 as shown in FIG. 5(B). That is, it corresponds to the shape of the container cavity 24. The upper punch 36 moves up and down by means of an upper slider (not shown). The lower portion of the upper punch 36 may close the upper portion of the cavity 33 in a planar shape. That is, it abuts against most of the upper surface of the mold 32.

Further, since the cavity 33 of the mold 32 of the first press molding machine 30 is provided in a shape corresponding to the form (shape) of the intermediate powder compact 110, the form of the intermediate powder compact 110 is as shown in FIGS. 6A and 6C. ~ When shown in Fig. 6E, they are also arranged in a shape corresponding to each other. When the annular shape is shown in Fig. 6A, it becomes a circular cylindrical shape. The elongated circular shaft shape shown in Fig. 6C is set to have the same cylindrical shape as that of Fig. 6B and is long in the up and down direction. The shape of the disk shown in Fig. 6D is also the same shape but shorter (thin) in the up and down direction. When the complex shape is shown in Fig. 6E, it becomes a corresponding complicated shape. Further, the cavity 63 of the mold 62 of the second press molding device 60 (second mold 61) is also provided in the same manner.

The mixed powder transfer device is a mixed powder in the container cavity The device that has been transferred to the cavity 33 of the first mold 31 that has been positioned corresponding to the container 23 is constituted by the lower punch 37, and the transfer operation is performed by the cooperation of the upper punch 36 and the mold 32.

That is, in FIG. 3(A), the upper punch 36 is lowered to abut against the upper surface of the mold 32 held on the first rotary table 80 (the mold holding portion 85). The mold 32 is depressed. Since the lower surface of the mold 32 abuts against the upper surface of the container 23, the container 23 is pressed. The position of the lower punch 37 in the up and down direction does not change. Thereby, the mixed powder 100 in the container cavity 24 is pushed up by the lower punch 37 and transferred into the mold 32 (cavity 33) of the first mold 31. At this time, since the size of the container cavity 24 in the up-and-down direction is larger than the dimension in the up-and-down direction of the cavity 33, the mixed powder 100 in the container cavity 24 is pre-compressed due to the pre-compression effect and transferred into the cavity 33. That is, the mixed powder transfer device (the upper punch 36, the lower punch 37) can transfer the mixed powder 100 in the container cavity 24 into the cavity 33 of the first mold 31 positioned corresponding to the container 23.

As shown in FIG. 3(B), the intermediate powder compact 110 of the mixed powder 100 can be compressed by the cooperation with the lower punch 37 in a state where the upper punch 36 is lowered to the lower position (the lowermost limit position). That is, as the first press molding machine 30, the mixed body intermediate compression body is formed by applying the first pressing force P1 from the first punch (upper punch 36) to the mixed powder 100 in the cavity 33 of the first mold 31 (middle) Powder compact 110). Since the mixed powder transfer device (the lower punch 37) is provided, a large amount of the mixed powder 100 can be supplied and can be compressed and transferred as compared with the case of directly filling into the cavity 33, thereby facilitating the high density of the intermediate powder compact 100. Chemical. The dimensional accuracy of the intermediate powder compact 110 is also high. When the slider rises, the upper punch 36 rises to the figure. The upper position shown in 3(C). At this time, the first rotary table 80 is raised to the upper limit position. The container 23 is returned to the original position shown in Fig. 3(A) by the spring 26.

The relationship between the pressing force P (first pressing force P1) in the first press molding machine 30 and the true density ratio (density ρ) of the intermediate powder compact 110 obtained in correspondence with this will be described with reference to Fig. 5 . The horizontal axis represents the applied pressure P by an index. The maximum capacity (pressure P) in this embodiment is 10 Ton/cm ² , which is set to the horizontal axis index 100. Pb is the mold damage pressure and has a horizontal axis index of 140 (14 Ton/cm ² ). The vertical axis represents the true density ratio (density ρ) by an index. The vertical axis index 100 corresponds to a true density ratio (density ρ) of 97% (7.6 g/cm ³ ).

In this embodiment, the base metal powder is a magnetic core coated with an insulating coating of glass, and the lubricant powder is selected from the group consisting of zinc stearate powder in the range of 0.2% by weight to 0.1% by weight and is the first pressing force. P1 intermediate compressed body mixed powder (intermediate green compact 110) is compressed to 82 to 92 corresponds to the vertical axis index [equivalent density ^{ρ (6.24g / cm 3 ~ 7.02g} / cm 3)] the true density ratio of 80% to 90% of the substance.

Meanwhile, the vertical axis index 102 corresponds to the density ρ (7.75 g/cm ³ ), and the true density ratio (density ρ) corresponds to 99%.

In addition, as the base metal powder, iron-based amorphous powder for magnetic core (Fe-Si alloy powder for magnetic core), iron-based amorphous powder for magnetic core, Fe-Si alloy powder for magnetic core, and pure iron powder for mechanical components can be selected. Wait.

Once the first pressing force P1 is increased, the density ρ obtained by the first press molding machine 30 rises with the characteristic A (curve) indicated by a broken line. At the first applied pressure P1 (horizontal axis index 100), the density ρ becomes 7.6 g/cm ³ . The true density ratio is 97%. Even if the first pressing force P1 is raised to a value higher than this, the increase in the density ρ is minute. There is a high possibility of mold damage.

Conventionally, when the density ρ obtained by pressurizing the maximum capacity of a press molding machine (pressing machine) cannot be satisfied, it is necessary to equip a larger pressing machine. However, even if the enlargement is, for example, the maximum capacity is changed to 1.5 times, the increase in the density ρ is minute. Therefore, the current situation is that the low density ρ (for example, 7.5 g/cm ³ ) obtained by a press machine is barely accepted.

Here, in particular, the use of a pressing machine directly, such as an increase from a vertical axis index of 100 (7.6 g/cm ³ ) to 102 (7.75 g/cm ³ ), can be understood as having an epoch-making significance. That is, if the density ρ can be increased by 2%, the magnetic properties (hyperbolic property) can be greatly improved and the mechanical strength can be drastically improved. Further, since the sintering treatment in a high-temperature atmosphere can be completely removed, the oxidation of the powder compact can be greatly suppressed (the core performance can be prevented from being lowered). In addition, construction or conversion to other machines with compression can be implemented.

In order to achieve the above, the lubricant can be melted (liquefied) by heating the intermediate powder compact 110 formed by the first press molding machine 30, and thereafter the second press forming process is performed by the second press molding machine 60. When the intermediate powder compact 110 is pressurized in the second press molding machine 60, the density B is increased according to the characteristic B (straight line) shown by the solid line in Fig. 5, and the height corresponding to the vertical axis index 102 can be achieved. Density (7.75 g/cm ³ ). The details will be described in the description of the second press molding machine 60.

Heating the heating machine 40, referring to Fig. 3 (D), (E) is heating positioning The first mold 31 and the mixed powder intermediate compressed body (intermediate powder compact 110) heated at the temperature rising position Z12 actively raise the temperature of the intermediate powder compact 110 to a temperature corresponding to the melting point temperature of the lubricant. The heating and heating machine 40 has a hollow cylindrical body 41 having a stopper 42 at its upper portion, a lifting rod 43 having a stopper 45 at its lower portion, and a accommodating portion 44 for accommodating the heater 47 at the upper portion, and a lifting force for the lifting rod 43 upward. The spring 48 is constructed. The lifting lever 43 is held at the initial upper position shown in Fig. 3(D) by the urging force of the spring 48 in a state where the stopper 45 is restricted by the stopper 42.

In this state, when the first mold 31 (mold 32) is placed (correspondingly positioned) on the accommodating portion 44, the first rotary table 80 is lowered to the lower limit position to be in the state of FIG. 3(E). Thus, the heater 47 is turned on to heat the intermediate powder compact 110. The timing at which the heater 47 is turned on can change the setting. For example, it may be set as the timing at which the intermediate powder compact 110 is placed as shown in FIG. 3(D). It can also be set to the on state as long as it is allowed by power conditions or production cycles.

The technical significance of the low-temperature heat treatment in the first press molding machine 30 will be described in relation to the first press-forming process. If the mixed powder 100 filled in the first mold 31 (mold 32) is observed, it is understood that the portion where the lubricant powder is sparse (sparse portion) and the denser portion (dense portion) in the relationship with the base metal powder . The dense portion reduces the interparticle frictional resistance of the base metal powder and the frictional resistance of the base metal powder and the inner surface of the mold. The sparse part should make these frictional resistances larger.

In the pressurization of the first press molding machine 30, the dense portion is composed of Because it is small in friction, it has excellent compressibility and is easy to compress. The sparse part has poor compressibility due to large friction and slow compression. In either case, it is difficult to perform compression corresponding to the value of the preset first pressing force P1. That is, the compression limit appears. When the fracture surface of the intermediate powder compact 110 taken out from the mold 32 in this state is magnified, the portion as the dense portion is integrally pressed against the base metal powder. However, a lubricant powder is also mixed. As a portion of the sparse portion, a small gap (space) remains between the pressed base metal powders. Almost no lubricant powder is visible.

Therefore, when the lubricant powder is removed from the portion as the dense portion, a compressible gap is generated. When a lubricant can be added to a part of the gap which is a sparse portion, the compressibility of the portion can be improved.

That is, the intermediate powder compact 110 after the completion of the first press molding is heated to a temperature (for example, 120 ° C) corresponding to the melting point of the lubricant powder, and the lubricant powder is melted (liquefied) to improve the fluidity thereof. The lubricant melted from the portion as the dense portion penetrates to the periphery thereof and is added to the portion of the sparse portion. Thereby, the intergranular frictional resistance of the base metal powder can be reduced, and the space occupied by the lubricant powder can also be compressed. It is also possible to reduce the frictional resistance of the particles of the base metal powder and the inner surface of the mold. That is, the liquefaction of the lubricant is promoted and the second press forming treatment is performed.

The intermediate powder compact transfer device (squeeze rod 50) transfers the intermediate powder compact 110 in the cavity 33 of the first mold 31 (mold 32) to the second mold 61 positioned at the transfer transition position Z13 (mold 62) The device within the cavity 63.

In Figure 3 (F), Figure 4 (G), the intermediate powder compact transfer The pressing rod 50 is formed by the pressing rod 50 and the transfer transition stage 55 positioned at the transfer transition position Z13, and the pressing rod 50 can be moved up and down between the upper limit position shown in FIG. 3(F) and the lower limit position shown in FIG. 4(G). Move back and forth. The rod diameter may be equal to or slightly smaller than the diameter of the upper punch 66 shown in Fig. 4(H).

3(F) shows a case where the first mold 31 is lowered from the upper limit position to the lower limit position and placed on the upper surface of the second mold 61 after the second mold 61 is correspondingly positioned on the upper surface of the transfer transition stage 55. In this state, the squeeze rod 50 can be lowered to transfer the mixed powder intermediate compression body 110 in the cavity 33 of the first mold 31 into the cavity 63 of the second mold 61.

That is, at the transfer transition position Z13 as shown in FIG. 4(G), the intermediate powder compact 110 can be transferred from the first mold 31 to the second mold 61. As seen from the second mold 61, at the receiving transition position Z21, the intermediate powder compact 110 is received from the first mold 31. That is, the transfer transition position Z13 and the reception transition position Z21 are the same position.

The second press molding machine 60 shown in Fig. 4(H) is for performing a second press forming process for applying the second pressing force P2 to the intermediate powder compact 110 set in the second die 61, and forming a high density. The mixed powder completes the device of the compact (completed powder compact 120).

The second mold 61 is composed of a lower mold (mold 62, lower punch equivalent 67) on the table side and an upper mold (upper punch 66) on the side of the slider (not shown), and is positioned at the position where the powder compact is formed. Z22. The shape of the cavity 63 of the mold 62 corresponds to the shape of the cavity 33 of the first mold 31 (mold 32). That is, it is set to a shape (hollow cylindrical shape) corresponding to the form (cylindrical shape) of the completed powder compact 120 shown in FIG. 5(B). The upper side of the mold 62 is convenient The intermediate powder compact 110 is received to be slightly larger than in the case of the mold 32.

In Fig. 4(H), the upper punch 66 is pressed into the cavity by a slider (not shown) which is movable up and down between the upper position and the lower position, and a second pressing force P2 is applied to the intermediate powder compact 110. The powder compact 120 is completed at a high density. The lower punch equivalent stage 67 that receives the second pressing force P2 has the same structure as the transfer transition stage 55, but may have the same structure including the lower punch 37 as shown in Fig. 3(B).

Further, the maximum capacity (pressure P) of the second press molding machine 60 in this embodiment is 10 Ton/cm ² as in the case of the first press molding machine 30. Therefore, the first press molding machine 30 and the second press molding machine 60 can be configured as one press machine, and the common sliders can be constructed to synchronously move the molds 31 and 61 simultaneously. From this point of view, it is advantageous to save the device and reduce the manufacturing cost of completing the powder compact 120.

The relationship between the pressing force (second pressing force P2) on the second press molding machine 60 and the density ρ of the finished powder compact 120 obtained correspondingly thereto will be described with reference to FIG.

The density ρ obtained by the second press molding machine 60 is a characteristic B as indicated by a solid line. That is, unlike the case of the first press molding machine 30 [according to the characteristic A shown by the broken line], the density ρ does not gradually increase as the second pressing force P2 increases. That is, the density ρ does not rise until the final first pressing force P1 (for example, the horizontal axis index 50, 75 or 85) in the first press forming step (PR3) is exceeded. When the second applied pressure P2 exceeds the final first applied pressure P1, the density ρ rapidly increases. The second press forming can be understood as just continuous The first press forming is performed.

Therefore, in the first press forming step, it becomes possible to increase the first pressing force P1 up to the value corresponding to the maximum capacity (horizontal axis index 100) at all times. It is possible to eliminate the time and energy consumed when the first press forming is continued after the compression limit. Thereby reducing manufacturing costs. Further, since it becomes easy to avoid overload operation exceeding the horizontal axis index 100, there is no need to worry about mold breakage. The overall operation is easy and safe and stable.

The product discharge device 70 is a device that discharges the completed powder compact 120 in the cavity 63 of the second mold 61 to the outside at the product discharge position Z23. In Fig. 4(I), the product discharge device 70 includes a discharge rod 71 positioned corresponding to the product discharge position Z23 and a discharge groove 73 assembled on the discharge table 77, which can be pressed into the cavity 63 by the discharge rod 71 to complete the powder. The green compact 120 is discharged.

That is, the discharge lever 71 can be moved up and down between the upper limit position (not shown) and the lower limit position shown in FIG. 4(I). The diameter of the rod is equal to or slightly smaller than the diameter of the upper punch 66 shown in Fig. 4(H). When the second mold 61 is positioned on the upper surface of the discharge table 77 and the discharge rod 71 is lowered to the lower limit position, the completed powder compact 120 in the cavity 63 of the mold 62 constituting the second mold 61 can be discharged from the discharge tank 73. .

Since the transfer (transport) method of the powder compact determines the speed of the production cycle, it is important to decide which method to use. Moreover, it is also important because the specific composition and structure are directly related to the saving, operation and maintenance, and manufacturing cost of the device. There are many examples It is used to transport (handle) the workpiece in a straight line.

In the invention, the rotation transmission mode using the two rotary stages 80, 90 is provided. In FIG. 2, the mixed powder filling position Z11, the heating temperature increasing position Z12, and the transfer transition position Z13 are disposed in isolation on the first circular locus R1 centered on the first axis Z1. Further, the receiving transition position Z21, the completed powder compact forming position Z22, and the product discharging position Z23 are disposed in isolation on the second circular locus R2 centering on the second axis Z2. In this embodiment, they are arranged at equal angles (120 degrees) in three equal parts. Moreover, it is constructed to use a first rotating table 80 that is rotatable about the first axis Z1 and a second rotating table 90 that is rotatable about the second axis Z2.

The interval between the first axis Z1 and the second axis Z2 is set to be the same position as the transfer transition position (longitudinal axis) Z13 and the reception transition position (longitudinal axis) Z21. The first rotating table 80 can be intermittently rotated in the DRL (counterclockwise) direction about the first axis Z1, so that the mold holding portion 85 can be positioned and stopped corresponding to the mixed powder filling position Z11, the heating temperature increasing position Z12, and the transfer transition position Z13. And stay in that position.

The first rotary table 80 can be moved up and down between the upper limit position and the lower limit position and can also be stopped at any of the upper limit position and the lower limit position. The upper limit position means a position that is in the state shown in FIGS. 3(A), (C), (D), and (F), and the lower limit position means that FIG. 3(B), (E), (F), and FIG. The position of the state shown in 4(G). Further, the first rotating table 80 generates a downward pressure that lowers the lifting rod 43 to the lower limit position against the urging force of the spring 48 shown in Figs. 3(D) and (E).

In FIG. 2, the first rotary table 80 is supported by a transfer drive shaft 87 (rotation drive shaft 88, lift shaft 89). Since the rotary drive shaft 88 is controlled by the servo motor to rotate the angle, the first rotary table 80 can be stopped and held at the set angle, so that the mold holding portion 85 can be correctly positioned corresponding to the respective positions Z11, Z12, and Z13. The lifting shaft 89, which is spline-connected to the rotary drive shaft 88, can selectively raise and lower the first rotary table 80 by the cylinder device and correspondingly position it at any of the upper limit position and the lower limit position. A first mold 31 (mold 32) is attached to the mold holding portion 85.

The second rotating table 90 can be intermittently rotated in the DRR (clockwise) direction about the second axis Z2, so that the mold holding portion 95 can be positioned corresponding to the receiving transition position Z21, the finished powder compact forming position Z22, and the product discharging position Z23. . It can be stopped and kept in each position. The transfer rotary shaft 97 is dedicated to the rotary drive, and in this embodiment, it does not have a lift function. That is, the second rotating stage 90 is maintained at a predetermined height, that is, the state shown in FIG. 3(F) and FIGS. 4(G), (H), and (I). A second mold 61 (mold 62) is attached to the mold holding portion 95.

In this embodiment, the plurality of (three) mold holding portions 85 on the first rotating table 80 are arranged at equal angles (120 degrees), and the first mold 31 is attached to each of the mold holding portions 85. Similarly, the plurality of (three) mold holding portions 95 are arranged at three equal angles (120 degrees) on the second rotary table 90, and the second mold 61 is attached to each of the mold holding portions 95.

In addition, any of the rotary tables 80 and 90 is formed using a large-diameter circular plate, but a plurality of bracket-shaped members may be equally divided into equal angles (120 degrees) and each of the bracket-shaped members may be mounted as the first and second axes. Z1 and Z2 are The construction of the center synchronous rotation.

Here, it can be understood that the first mold transfer device 81, the pre-heated powder green transfer device 82, and the heated powder green transfer device 83 utilize the first rotary table 80 (the first mold transfer device 81, the pre-heated powder green transfer) The device 82 and the heated powder compact conveying device 83) are integrally formed. Each of the conveying devices 81, 82, 83 is intermittently rotated in the DRL direction centering on the first axis Z1 of the first rotating table 80, and the mold holding portion 85 is conveyed and conveyed along the first circular path R1. The lifting of the first rotary table 80 is combined in the middle.

The first mold transporting device 81 transports the first mold 31 located at the transfer transition position Z13 shown in FIG. 3(F) to the mixed powder filling position Z11 shown in FIG. 3(A), and the first mold 31 is located The container 23 on the mixed powder filling position Z11 is correspondingly positioned. In the middle, the first mold 31 is raised from the lower limit position to the upper limit position. The first mold transfer device 81 can also be referred to as a first mold return transfer device from the function of returning the first mold 31 from the transfer transition position Z13 to the mixed powder filling position Z11.

The pre-heating powder green conveyance device 82 conveys the first mold 31 located at the intermediate powder green compact forming position (mixed powder filling position Z11) shown in Fig. 3(B) from the intermediate powder compact forming position (mixed powder filling position Z11) The heating temperature rising position Z12 shown in FIG. 3(E) is positioned and the first mold 31 is positioned corresponding to the heating temperature rising position Z12. In the middle, the first mold 31 rises from the lower limit position shown in FIG. 3(B) to the upper limit position shown in FIG. 3(C). Next, the first mold 31 is transferred to the drawing by the rotation of the first rotary table 80. The heating temperature rising position Z12 shown in 3 (D). Further, the first mold 31 is mounted (correspondingly positioned) on the accommodating portion 44 at the upper limit position, and thereafter, the lowering operation is performed by the lowering operation of the elevating rod 43.

After heating, the powder green transfer device 83 transfers the first mold 31 in which the mixed powder intermediate compressed body 110 is housed from the heating temperature rising position Z12 shown in Fig. 3(E) to the transfer transition position Z13 shown in Fig. 3(F). By the raising and lowering operation of the first rotating table 80, the first die 31 is raised to the upper limit position in the middle, and is lowered to the lower limit position after being correspondingly positioned at the transfer transition position Z13.

Further, it can be understood that the second mold transfer device 91, the completed powder green transfer device 92, and the second mold return transfer device 93 utilize the second rotary table 90 (the second mold transfer device 91, the completed powder green transfer device 92, and The second mold return conveyor 93) is constructed in one piece. Each of the conveying devices 91, 92, 93 conveys the mold holding portion 95 along the second circular path R2 and conveys the second mold 61 by intermittent rotation in the DRR direction about the second axis Z2 of the second rotating table 90.

The second mold transporting device 91 transports the second mold 61, which is located at the receiving transition position Z21 shown in FIG. 4(G) and houses the intermediate powder compact 110, to the finished powder compact forming position Z22 shown in FIG. 4(H). Positioned corresponding to the lower punch equivalent 67 located at the completion of the powder compact forming position Z22. The second rotary table 90 is rotated only according to 120 degrees.

The completed powder compact conveying device 92 transports the second mold 61 containing the completed powder compact 120 from the completed powder compact forming position Z22 shown in FIG. 4(H) and positions the second mold 61 correspondingly to FIG. 4 ( I) The product exit position Z23 is shown. The second rotary table 90 rotates only in accordance with 120 degrees in the DRR direction.

The second mold return conveying device 93 conveys the second mold 61 after the completion of the powder compact 120 is discharged from the product discharge position Z23 to the receiving transition position (product discharge position Z23) shown in FIG. 3(F), and the second mold 61 is used. Correspondingly positioned at the receiving transition position (product discharge position Z23). That is, the second mold 61 is returned before the next cycle.

The powder green conveying device is configured as a rotary table and is conveyed along a circular path. Further, the transfer mode of the powder compact is set so as to be directly transferred from the first die 31 to the second die 61 as shown in Figs. 3(F) and 4(G) to transfer the transition. When such a rotary transfer and push-out transfer mode is set, compared with the conventional transfer mode (using a robot or a transfer device to transport a workpiece in a straight line in a straight line), there is no need to worry about the workpiece falling off, and it is easy to solve the collision between the workpiece and the slider or the mold. The problem can be transmitted quickly and correctly. The same applies to the transfer of the mixed powder 100 shown in Figs. 3(A) and (B).

In the high-density molding apparatus 1 of the mixed powder according to the embodiment, the high-density molding method is carried out by the following procedure. The processing procedure shown in FIG. 1(A) and the transmission operation described in FIG. 1(B) will be described with reference to FIG. 1(B). Further, a symbol (for example, Z22) enclosed in parentheses in the square indicating each step indicates the position at which the step is performed (finished powder compact forming position).

(Preparation of mixed powder)

The base metal powder (the core is coated with iron powder with a glass insulating coating) Finally, a mixed powder 100 in a loose state was prepared by mixing with 0.2 wt% of a lubricant powder (zinc stearate powder). It is supplied to the mixed powder feeder 10 only in a predetermined amount (step PR0 of Fig. 1).

(filling of mixed powder)

At a predetermined time, the mixed powder feeder 10 is transported from a predetermined position (not shown) to the replenishment position (broken line) shown in FIG. 3(A). Then, the supply port of the mixed powder feeder 10 is opened, and the quantitative mixed powder 100 is filled into the container device 20 [empty container cavity 24] (step PR1 of FIG. 1). For example, it can be filled in 2 seconds. After filling, the supply port is closed, and the mixed powder feeder 10 returns to a predetermined position. At this time, the first mold transfer device 81 is activated, and the first mold 31 (mold 32) returns from the state of FIG. 3(F) to the state of FIG. 3(A).

(transfer of mixed powder)

When the upper punch 36 is lowered in the state shown in FIG. 3(A), the first die 31 is lowered together with the first rotary table 80, and the upper punch 36 pushes the first die 31 and the container 23 against the urging force of the spring 26. Press down. Since the lower punch 37 is positioned and fixed at a prescribed position, the mixed powder 100 in the container 23 is pre-compressed and transferred into the cavity 33 of the first mold 31 (mold 32). That is, the mixed powder transfer device (lower punch 37) is activated.

(Formation of intermediate powder compact)

Further, the upper punch 36 is lowered to pressurize the mixed powder 100 in the mold 32 (cavity 33) with the first pressing force P1. In FIG. 3(B), the first press forming process (step PR3 of FIG. 1) is performed. The powder (solid) lubricant exerts sufficient lubrication. The density ρ of the compressed intermediate powder compact 110 increases with the characteristic A (dashed line) of FIG. When the first applied pressure P1 reaches a pressure (3.0Ton/cm ² ) equivalent to the horizontal axis index (for example, 30), the true density ratio is increased to 85%, that is, the density ρ is 6.63 g/cm ³ (corresponding to the longitudinal axis). Index 87). For example, 8 seconds of press forming is completed. The formed intermediate powder compact 110 stays in the cavity 33 of the first mold 31.

(Transfer of intermediate powder compact)

In Fig. 3(C), the powder green transfer device 82 before heating is started. When the upper punch 36 is raised to the upper position, the first die 31 is raised to the upper limit position (a position lower than the position above the upper punch 36) in a state in which the intermediate powder compact 110 is accommodated. Next, the first mold 31 and the intermediate powder compact 110 are transferred from the intermediate powder compact forming position (mixed powder filling position Z11) to the heating temperature rising position Z12 shown in FIG. 3(D). The first rotary table 80 is rotated by only 120 degrees in the DRL direction of FIG. The container 23 returns from the lower limit position to the initial position (upper limit position) shown in Fig. 3(A) before the next cycle. The first mold 31 is heated by the heating device 40 (the accommodating portion 44) at the upper limit position (the position lower than the upper limit position of the first die 31) at the heating temperature increasing position Z12 as shown in FIG. 3(D) by the urging force of the spring 26. ) Corresponding to positioning. Next, the lifter 43 is lowered, and the first mold 31 is correspondingly positioned at the lower limit position (heating position) shown in FIG. 3(E).

(heating and heating)

In FIG. 3(E), when the accommodating portion 44 is lowered to the lower limit position (a position lower than the lower limit position of the first die 31), the heating and heating machine 40 (heater 47) is activated. The intermediate powder compact 110 in the mold 32 is heated to a temperature corresponding to the melting point of the lubricant powder (for example, 120 ° C) (step PR4 of Fig. 1). That is, the lubricant is melted, and the flow of the lubricant in the intermediate powder compact 110 becomes uniform by the flow thereof. The heating and heating time is, for example, 8 seconds to 10 seconds. The timing of starting the heater 47 is not limited to this. For example, it can also be started from the state of FIG. 3(D).

(Transfer and reception of the intermediate powder compact that has been heated)

The powder green conveyance device 83 is started after heating at the end of heating and heating. As shown in FIGS. 3(E) and (F), the intermediate powder compact 110 that has been heated is transferred from the heating temperature increasing position Z12 to the transfer transition position Z13 while being stored in the first mold 31. That is, the first rotary table 80 is rotated by only 120 degrees in the DRL direction of FIG. Since it is not conveyed in a state of being exposed to the atmosphere, it is almost impossible to determine that the temperature of the intermediate powder compact 110 is lowered. Further, the first mold 31 (mold 32) is placed on the second mold 61 that is standby (corresponding to positioning) on the transfer transition stage 55. As a result, the intermediate powder compact transfer device (ejection rod 50) is activated. That is, as shown in FIG. 4(G), the push-out lever 50 is lowered from the upper position of FIG. 3(F), and the heated intermediate powder compact 110 accommodated in the first mold 31 is transferred into the second mold 61 ( Step PR5) of Figure 1. After the transfer is completed, the push-out lever 50 returns to the upper position.

(return transmission of the first mold)

When the intermediate powder compact 110 completes the transfer from the first die 31 to the second die 61, the first die transfer device 81 raises the first die 31 shown in FIG. 4(G) to the upper limit of FIG. 3(F). The position continues to return from the transfer transition position Z13 to the mixed powder filling position Z11 as shown in Fig. 3(A). That is, it is positioned corresponding to the container 23. At this time, the first rotary table 80 is also rotated by only 120° in the DRL direction.

(Transfer of intermediate powder compact)

On the other hand, the second mold transfer device 91 is also activated. The intermediate powder compact 110 received at the receiving excessive position Z21 (transfer transition position Z13) of Fig. 3(F) is transferred from the receiving transition position Z21 of Fig. 4(G) to the finished powder compact forming position of Fig. 4(H). Z22. The intermediate powder compact 110 is also conveyed in a state of being housed in the second mold 61. The second rotary table 90 is rotated by only 120 degrees in the DRR direction as shown in FIG.

(Complete the formation of powder compact)

In FIG. 4(H), the upper punch 66 is lowered from the upper position together with the slider (not shown). The lower punch stage 67 receives the second pressing force P2 in a stationary state. That is, the intermediate powder compact 110 which has been heated in the mold 62 (cavity 63) is pressurized at the second pressing force P2. The liquid lubricant is created to provide adequate lubrication. In particular, sweating occurs, and the lubricant flows out in all directions as the pressure is formed. Not only the basic metal particles can effectively reduce the frictional resistance between the particles and the mold. The density ρ of the compressed intermediate powder compact 110 increases with the characteristic B (solid line) of FIG. That is, when the second applied pressure P2 exceeds the horizontal axis index (for example, 30...plus pressure 3.0Ton/cm ² ), the density ρ rapidly increases from 6.63 g/cm ³ to a density ρ corresponding to the vertical axis index 102 (7.75 g). /cm ³ ). When the second pressing force P2 is raised to the horizontal axis index of 100 (10 Ton/cm ² ), the density ρ (7.75 g/cm ³ ) as a whole becomes uniform. Here, for example, when the second press forming process of 8 seconds is completed, the powder compact 120 is completed in the mold (41) (step PR6 of FIG. 1). Thereafter, the upper punch 66 is raised to the upper position by the slider. The finished powder compact 120 corresponding to the density ρ (7.75 g/cm ³ ) of the vertical axis index 102 is not deteriorated and melted because the lubricant powder has a low melting point. Therefore, the eddy current loss is small, and a high-quality magnetic core powder for magnetic core having a high magnetic flux density can be efficiently produced.

(Complete the transfer of the powder compact)

In this way, the completion of the powder compact conveying device 92 is completed, and the completion of the powder compact 120 in the state of being stored in the second mold 61 is transmitted from the completed powder compact forming position Z22 of FIG. 4(H) to FIG. 4(I). The product is discharged at position Z23. Correspondingly, it is positioned at the product discharge position Z23, that is, the discharge table 77. During this time, the discharge lever 71 stands by at the upper position. The second rotary table 90 is rotated by only 120° in the DRR direction.

(product discharge)

The product discharge device 70 is activated, and in FIG. 4(I), the discharge lever 71 is lowered from the upper position to push the completed powder compact 120 in the second mold 61 to the discharge groove 73. The product discharge ends (step PR7 of Fig. 1). after the end, The discharge lever 71 is raised to the upper position to become the standby state.

(return transmission of the second mold)

The second mold return conveyor 93 returns the second mold 61 from the product discharge position Z23 of Fig. 4(I) to the reception transition position Z21 (transfer transition position Z13) of Fig. 3(F). The second rotary table 90 is rotated by only 120° in the DRR direction. Since there is no lifting action in the middle, it can be quickly returned.

(manufacturing cycle)

According to the high-density molding method using the above steps, the metal powder (mixed powder 100) to be sequentially supplied can be simultaneously subjected to the first press molding treatment, the heating temperature treatment, and the second pressure molding treatment. A high-density powder compact is produced in a period of 12 seconds to 14 seconds obtained by adding a powder compact transfer time (for example, 2 seconds to 4 seconds) to the longest heating and heating treatment time (10 seconds) (completed powder pressure) Blank 120). That is, it is understood that the manufacturing and production time is remarkably improved even when compared with the high-temperature sintering treatment time of 30 minutes or more in the conventional example. For example, it is possible to stably supply a component for an automobile having high mechanical strength, a component for electromagnetic equipment having excellent magnetic strength and mechanical strength, and a large contribution to reducing the production cost.

Thus, according to this embodiment, the mixed powder 100 can be loaded into the container 23, and then the intermediate pressing compact 110 is formed by transferring and applying the first pressing force P1 to the first mold 31, and heating and actively raising the temperature to the lubricant powder. Intermediate powder compact at melting point temperature (eg 120 ° C) The 110 is loaded into the second mold 61 and the second pressing force P2 is applied to form the high-density forming method of the powder compact 120, so that the high-density powder compact can be stably produced and the manufacturing cost can be greatly reduced, and can be used to adapt to the actual situation. The filling operation of the produced mixed powder 100 is made efficient, and the size and weight of the first mold 31 and the like are reduced.

Further, since the sintering treatment at a high temperature for a long period of time can be removed, not only the oxidation of the powder compacts 110 and 120 but also the high utilization rate of energy consumption and the manufacturing cost can be greatly reduced. It is also welcomed in protecting the global environment.

Further, since the melting point of the lubricant powder is a low melting point in a temperature range of from 90 ° C to 190 ° C, sufficient lubrication of the lubricant in the first pressurizing step can be ensured. It also helps to inhibit oxidation while increasing the selectivity of the lubricant.

Since the second mold 61 can be preheated to a temperature corresponding to the melting point before the intermediate powder compact 110 is received, the fluidity of the melted lubricant in the second press forming can be further improved in all directions. That is, not only the base metal particles can be greatly reduced but also the frictional resistance between the particles and the second mold 61 can be reduced and maintained.

Since the first mold 31 can be preheated after the formation of the intermediate powder compact 110 is completed, the shortening of the manufacturing cycle time including the temperature rise time of the intermediate powder compact 110 can be promoted.

Further, since the value of the second pressing force P2 can be made equal to the value of the first pressing force P1, the fluidity of the melted lubricant in the press forming in all directions can be further improved. In addition to the basic metal particles The frictional resistance between the particles and the second mold 61 can also be greatly reduced and maintained. Moreover, the ease of carrying out the press forming step and its operation can indirectly contribute to further reducing the manufacturing cost of the powder compact, and can also simplify the construction on the basis of, for example, one press machine when the apparatus is implemented.

In addition, even if the base metal powder is replaced with any one of the iron-based amorphous powder for magnetic core and the Fe-Si alloy powder for magnetic core, and the other conditions are the same, A magnetic mind assembly having magnetic characteristics corresponding to the type of base metal powder is efficiently and stably manufactured.

In summary, it is impossible to increase the density to a value corresponding to a vertical axis index of 100 or more depending on the capability of the existing device (for example, a compression machine) (the horizontal axis index of FIG. 5). Conversely, the same device can be used for the same device. High enough to correspond to the density of the vertical axis index 102. This fact is acclaimed in this technical field as epoch-making.

Further, the high-density device 1 is composed of a mixed powder feeder 10, a mixed powder transfer device (lower punch 37), a first press molding machine 30, a heating and heating machine 40, and an intermediate powder compact transfer device (ejection rod 50). Since the second press molding machine 60 and the product discharge device 70 are configured, the above-described high density method can be reliably and stably performed, and it can be realized at low cost. easy to use.

Since the first mold transfer device 81 that transports the first mold 31, the pre-heated powder green transfer device 82, and the heated powder green transfer device 83 are provided and the second mold transfer device 91 that transports the second mold 61 is provided, the completion is completed. Powder green transfer device 92 and second mold return conveyor By setting 93, the simplification of the apparatus can be achieved and the powder compact can be conveyed quickly and smoothly.

Further, since the mixed powder filling position Z11, the heating temperature rising position Z12, and the transfer transition position Z13 are disposed on the first circular trajectory R1 centered on the first axis Z1, and the transition position Z21 is received, the powder compact is completed. The forming position Z22 and the product discharging position Z23 are disposed on the second circular trajectory R2 centered on the second axis Z2, and the respective rotating devices 81, 82 are constructed using the first rotating table 80 rotating around the first axis Z1. 83. The second rotating table 90 rotating around the second axis Z2 is used to construct the respective conveying devices 91, 92, 93, so that the device can be further simplified. This can lead to further simplification of the manufacturing line and make the operation easier. Compared with the conventional straight-line transmission direction, overall rapid transmission and small size and light weight can be achieved.

(Second embodiment)

This embodiment is shown in Figs. 7 and 8 . The basic configuration and function setting is the same as that of the first embodiment (Figs. 1 to 6E), but the second mold 61 (mold 62) constituting the second press molding machine 60 is provided with the second preheating device 64. Further, the first mold 31 (mold 32) constituting the first press molding machine 30 is provided with a first preheating device 34.

That is, it is set to preheat the second mold 61 and prevent the temperature of the intermediate powder compact 110 which has been heated and lowered. Furthermore, the first mold 31 can be preheated and the intermediate powder compact 110 can be preheated. In this embodiment, both the first preheating device 34 and the second preheating device 64 are provided. However, any one of them can be set according to the operating temperature environment.

In addition, FIG. 7 (FIG. 8) corresponds to FIG. 3 (FIG. 4) concerning the first embodiment. Others (Fig. 1, Fig. 2, Fig. 5, Fig. 6A to Fig. 6E) are the same as those in the first embodiment.

In the implementation, the temperature of the heated intermediate powder compact 110 is not lower than the temperature exceeding the certain temperature range before the timing at which the second pressing force P2 is applied in the second mold 61, even if the second mold 61 is not preheated. High density forming of the present invention can also be practiced. Further, it is not necessary to preheat the first mold 31 before the heating and heating step to perform the preheating of the intermediate powder compact 110. In this case, the preheating function of the second mold 61 and the first mold 31 for preheating may not be provided.

However, when the heat capacity of the intermediate powder compact 110 is small, the transfer time to the second mold 61 or the transport path is long, the intermediate powder compact 110 that has been heated according to the composition of the mixed powder 100 or the form of the intermediate powder compact 110 or the like is used. The temperature may be lowered before the time at which the formation of the powder compact 120 is started. In this case, the second mold 61 is preheated to obtain a preferable molding effect.

In Fig. 8, on the second mold 61 (mold 62), a second preheating device (heater) 64 which can change the set temperature is provided. Before the second preheating device 64 receives (loads) the intermediate powder compact 110, the second preheating device 64 is heated (preheated) to a temperature corresponding to the melting point of the lubricant powder (zinc stearate) (eg 120 ° C). The warmed intermediate powder compact 110 can be received without cooling. Thereby, it is possible to prevent the previously melted (liquefied) lubricant from solidifying again and to ensure lubrication.

This preheating step is carried out before the completion of the powder compact forming step (PR6) of the first embodiment. This preheating can be formed by heating before completion of the press forming of the powder compact 120. Thus, the fluidity of the lubricant melted in the press molding in all directions can be further improved, so that the frictional resistance between the particles and the second mold 61 (mold 62) can be greatly reduced and maintained in addition to the base metal particles.

Further, when the composition of the mixed powder 100 and the form of the intermediate powder compact 110 are different, when the heat capacity of the intermediate powder compact 110 is large, when a large heating and heating machine is not provided, or when the working environment temperature is low, there is an intermediate powder compact It takes a long time for the heating of 110 to heat up. At this time, it is preferable to preheat the first mold 31. Therefore, in this embodiment, the first mold 31 is preheated.

Therefore, the first mold 31 (mold 32) incorporates a first preheating device (heater) 34 that can change the set temperature, and is set in the state shown in FIG. 7(A) [corresponding to FIG. 3(A)]. The first mold 31 can be preheated by turning on the heater. That is, it can be used as a part of the heating and heating machine 40. The heating time of the heating and warming machine 40 can be reduced by the preheating, and the production cycle can be shortened. That is, since the two heaters 47, 34 can be heated from the outer surface and the lower surface as shown in Figs. 7(D) and (E), the temperature of the entire intermediate powder compact 110 can be uniformly and rapidly increased.

This preheating step is performed after the intermediate powder compact forming step (PR3) of the first embodiment is completed. In this embodiment, it is provided that the preheating can be performed by heating before being transferred to the heating and heating machine 40.

In addition, the first preheating device 34 and the second preheating device 64 In this embodiment, the electric heating method (electric heater) is provided, but it may be implemented by a heating device or the like of a circulation type using hot oil or hot water circulation preheating.

As described above, according to this embodiment, the same operational effects as in the first embodiment can be achieved, and since the second mold 61 can be preheated in advance, it is possible to further improve the press forming at the second pressing force P2. Since the directional fluidity of the lubricant is melted, the frictional resistance between the particles and the second mold 61 can be greatly reduced and maintained in addition to the base metal particles.

Further, since the first mold 31 can be preheated, when the preheating is performed in advance, the load of the heating and heating machine 40 can be lowered and the intermediate powder compact 110 can be rapidly heated. Can shorten the production cycle.

10‧‧‧Mixed powder feeder

20‧‧‧ container installation

21‧‧‧ hollow cylindrical body

22‧‧‧

23‧‧‧ Container

24‧‧‧ container cavity

25‧‧‧

26‧‧‧ Spring

30‧‧‧First Press Forming Machine

31‧‧‧First mould

32‧‧‧Mold

33‧‧‧ cavity

36‧‧‧Upper punch

37‧‧‧Under punch (mixed powder transfer device)

40‧‧‧heating machine

41‧‧‧ hollow cylindrical body

42‧‧‧

43‧‧‧ Lifting rod

44‧‧‧ 收纳 department

45‧‧‧

47‧‧‧heater

48‧‧‧ Spring

50‧‧‧ Launched rod (intermediate powder compact transfer device)

55‧‧‧Transfer transition station

61‧‧‧Second mold

62‧‧‧Mold

63‧‧‧ cavity

80(83)‧‧‧First rotary table (first mold transfer device, pre-heating powder Final green conveying device, heated powder green conveying device), second Rotary table (second mold transfer device, complete powder compact transfer device) , the second mold return conveyor)

90‧‧‧ mixed powder

110‧‧‧Intermediate powder compact (mixed powder intermediate compression body)

Z11‧‧‧ Mixed powder filling position (intermediate powder compact forming position)

Z12‧‧‧heating position

Z13(Z21)‧‧‧Transfer transition position

Claims (10)

A high-density forming method of a mixed powder, characterized in that a mixed powder is filled into a container cavity, the mixed powder is a mixture of a base metal powder and a low-melting lubricant powder; and the mixed powder in the container cavity is transferred to the container a first pressure-molded mixed powder intermediate compression body is applied to the mixed powder in the cavity of the first mold corresponding to the positioned first mold cavity; the first mold and the mixed powder intermediate compression body are heated and formed, and the mixed powder is intermediate The compressed body is heated to a temperature corresponding to the melting point; the heated mixed intermediate compressed body is positioned corresponding to the first mold and the second mold, and the mixed powder intermediate compressed body in the cavity of the first mold is transferred to the first The mold corresponds to the cavity of the second mold positioned; a second pressure is applied to the mixed powder intermediate compression body in the cavity of the second mold to form a high-density mixed powder to complete the compression body. The high-density molding method of the mixed powder according to the first aspect of the invention, wherein the lubricant powder has a melting point of a low melting point and a melting point temperature of from 90 ° C to 190 ° C. The high-density molding method of the mixed powder according to the first or second aspect of the invention, wherein the second mold is preheated before receiving the mixed powder intermediate compressed body. The high-density molding method of the mixed powder according to the first or second aspect of the invention, wherein the molding of the compressed body is completed in the mixed powder The first mold is preheated afterwards. The high-density molding method of the mixed powder according to the first or second aspect of the invention, wherein the second pressing force is selected to be equivalent to the first pressing force. A high-density forming device for mixing powder, comprising: a mixed powder supply device capable of filling a mixed powder into a container chamber positioned at a filling position of the mixed powder, wherein the mixed powder is a mixture of a base metal powder and a low-melting lubricant powder; a powder transfer device for transferring the mixed powder in the container cavity to the first mold cavity corresponding to the container; the first press molding machine applies the first additive from the first punch to the mixed powder in the cavity of the first mold Press-forming the mixed powder intermediate compression body; heating the heating machine, heating the first mold and the mixed powder intermediate compression body positioned at the heating temperature rising position, and heating the temperature of the mixed powder intermediate compression body to a temperature corresponding to the melting point; The device transfers the mixed powder intermediate compression body in the cavity of the first mold to the second mold positioned at the transfer transition position; the second press molding machine is positioned from the second punch pair to complete the compression body forming position The mixed powder intermediate compression body in the cavity of the second mold is applied with a second pressure forming high density Powder was complete compression of the body; and a product discharge device provided within the mixing chamber the powder discharge position in the article to be discharged compressed body of the second mold is completed. High density of mixed powder as described in claim 6 a forming device, wherein: a first mold transfer device is disposed, configured to transfer the first mold and can be positioned corresponding to a container that has been positioned at a mixed powder filling position; and the powder compact transfer device before heating is set to be the first The mold is transferred from the intermediate powder compact forming position and can be positioned corresponding to the heating temperature rising position; the heated powder compact transfer device is configured to transfer the first mold containing the mixed powder intermediate compression body from the heating temperature rising position and can communicate with the transfer transition Position corresponding positioning; the second mold transfer device is configured to transfer the second mold containing the mixed powder intermediate compression body from the transfer transition position and can be positioned corresponding to the completed powder compact forming position; the powder compact transfer device is set to be set to Transferring the second mold in which the mixed powder is completed to complete the compressed body from the completion of the powder compact forming position and positioning corresponding to the product discharge position; and the second mold returning transfer device is disposed to transfer the mixed powder from the product discharge position to complete the compression The second mold of the body and the receiving transition position pair Positioning. The high-density molding apparatus for mixed powder according to claim 7, wherein the mixed powder filling position, the heating temperature rising position, and the transmission transition position are disposed on the first circular trajectory centered on the first axis, and The transfer transition position, the completed powder compact forming position, and the product discharge position isolation are disposed on a second circular trajectory centered on the second axis; The first mold transfer device, the pre-heating powder green transfer device, and the heated powder green transfer device are constructed using a first rotary table that is rotatable about a first axis; the second mold transfer device completes powder compact transfer The device and the second mold return transfer device are constructed using a second rotary table that is rotatable about a second axis. A high-density molding apparatus for a mixed powder according to claim 6 or 7, further comprising a first preheating device for preheating the first mold. A high-density molding apparatus for a mixed powder according to claim 6 or 7, further comprising a second preheating device for preheating the second mold.