JPH10259403A - Compacting apparatus and compacting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compacting apparatus which can easily produce a high quality molding in a short time, and a compacting method. SOLUTION: The compacting apparatus 1 is the apparatus for compacting a bond magnet and a die 2 for compacting and a tool for compacting a molding material 15 filled in the die 2. The die 2 is constituted of a first part (heating part) 3 for heating the molding material 15, a second part (cooling part) 5 for cooling the molding material 15 and a heat insulating part 4 positioned between the first part 3 and the second part 5. The tool 6 is constituted of an upper punch 7 and a lower punch 8 pressing the molding material 15 mutually from the reverse direction. The upper punch 7 and the lower punch 8 can relatively be shifted in the axial direction in the molding space to the die 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a compression molding apparatus and a compression molding method, and more particularly to a compression molding apparatus and a compression molding method for producing a bonded magnet by compression molding.

[0002]

2. Description of the Related Art A bonded magnet is manufactured by shaping a mixture (compound) of a magnet powder and a binder resin (organic binder) into a desired magnet shape. This molding method is roughly classified into a compression molding method, an injection molding method and an extrusion molding method.

In the compression molding method, a compound, which is a mixture or kneaded product of a magnet powder and a binder resin (organic binder), is filled in a press mold, and the compound is compression-molded to obtain a molded body. When the binder resin is a thermosetting resin, it is cured to form a magnet. In this method, molding can be performed with a smaller amount of the binder resin than in other methods, so that the amount of resin in the obtained magnet is reduced, which is advantageous for improving magnetic properties.

However, the production of magnets by such a compression molding method has the following disadvantages. That is,
The manufactured rare earth bonded magnet has a high density of the molded body, but tends to have a high porosity, and therefore has low mechanical strength and poor corrosion resistance. For this reason, especially in the compression molding method, high-pressure molding in which the molding pressure is as high as 70 kgf / mm ² or more has been performed. However, high-pressure molding imposes a heavy burden on a molding machine.

In order to reduce the molding pressure, there has been proposed a method of warm molding, that is, a method of molding in a mold temperature range of the melting temperature of the binder resin. In this case, a heater is provided inside or outside the mold, and the molding material is compression-molded while the mold is heated to a predetermined temperature by operating the heater,
Thereafter, the heater is turned off while the molded body is left in the mold, and the molded body is naturally cooled (cooled) for each mold, forcibly cooled with water, cold air, or the like, or the molded body is removed from the mold. And natural cooling (cooling).

In the case where the binder resin is a thermosetting resin, a method is employed in which, after compression molding, the mold is further heated to a curing temperature and cured to a temperature at which the shape of the resin can be maintained in the mold.

However, in such a method, the production process is complicated, and it takes a long time to cool the molded body, so that the productivity is low. In particular, when the molded body is removed from the mold and cooled, in order to maintain the shape of the molded body, it is necessary to wait until the temperature of the molded body has decreased to some extent before removing the molded body. However, the time required to complete the molding is long.

[0008] If the cooling temperature of the molded article is not appropriate, the molded article is deformed and the adhesive strength and the filling property of the magnet powder due to the resin component are reduced, and the density of the molded article is reduced (increased pores). Since the mechanical strength of the molded body is reduced, cooling conditions must be strictly controlled in order to produce a high quality and stable quality bonded magnet.

In the case where the binder resin is a thermosetting resin, a step of curing the uncured binder resin by heating the molded body in a mold after molding or after removing the material from the mold (curing). Ring) is required. Therefore, the number of manufacturing steps increases, and it takes a long time to manufacture the bonded magnet.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a compression molding apparatus and a compression molding method capable of easily and quickly obtaining a high quality molded article.

[0011]

This and other objects are achieved by the present invention which is defined below as (1) to (23).

(1) A compression molding die, and a tool for compressing a molding material filled in the die, wherein the tool is movable relative to the die. Wherein the mold has a first portion capable of holding a first temperature, and a second portion capable of holding a second temperature different from the first temperature. And the first
And the second part are arranged along the direction of relative movement between the tool and the mold.

(2) A mold for compression molding, and a tool for compressing a molding material filled in the mold, wherein the tool is movable relative to the mold. Compression molding apparatus, wherein the mold comprises a first part for heating the molding material and a second part for cooling the heated molding material.
Wherein the first part and the second part are arranged along the direction of relative movement between the tool and the mold. .

(3) The compression molding apparatus according to the above (1) or (2), wherein the tool comprises an upper punch and a lower punch which press the molding material from directions opposite to each other.

(4) It has a plurality of molds for compression molding, and a tool for compressing the molding material filled in the molds.
A compression molding apparatus configured to allow the tool to move relatively to the mold, wherein each of the molds includes a first portion capable of maintaining a first temperature; A second portion capable of maintaining a second temperature different from the first temperature, and wherein the first portion and the second portion are in a relative movement direction between the tool and the mold; And each of the molds is configured to be able to move between a material supply position where the molding material is filled into the mold and a molding position where compression molding is performed by the tool. A compression molding apparatus.

(5) It has a plurality of dies for compression molding, and a tool for compressing the molding material filled in the dies,
A compression molding apparatus, wherein the tool is configured to be movable relative to the mold, wherein each of the molds includes a first portion for heating a molding material, and a heated molding material. And a second part for cooling the tool, and the first part and the second part are arranged along a direction of relative movement between the tool and the mold, A compression molding apparatus, wherein each of the molds is configured to be able to move between a material supply position at which a molding material is filled into the mold and a molding position at which compression molding is performed by the tool.

(6) The tool has an upper punch and a lower punch for pressing the molding material from opposite directions, one of which is installed at the molding position, and the other which moves together with the mold. ) Or (5).

(7) The compression molding apparatus according to any one of (1) to (6), wherein the first portion and the second portion are arranged via a heat insulating portion.

(8) The compression molding apparatus according to any one of the above (1) to (7), wherein the molding material is a composition for producing a bonded magnet.

(9) A mold having a first portion capable of maintaining a first temperature and a second portion capable of maintaining a second temperature different from the first temperature, and a mold in the mold. Using a tool for compressing a molding material filled in a molding material, wherein the molding material located in the first portion is relatively moved to the second portion. A compression molding method characterized by giving a temperature change to the molding material before and after the movement.

(10) A mold having a first portion for heating the molding material, a second portion for cooling the heated molding material, and a tool for compressing the molding material filled in the mold. And a compression molding method for compressing and molding the molding material, wherein the molding material is compressed while being heated in the first portion, and then relatively moved to the second portion for cooling. Characteristic compression molding method.

(11) A mold having a first portion for heating the molding material and a second portion for cooling the heated molding material, and a tool for compressing the molding material filled in the mold. A compression molding method of compressing and molding a molding material, wherein the molding material is heated in the first portion, and then relatively moved to the second portion to be compression molded and cooled. A compression molding method characterized by the above-mentioned.

(12) The compression molding method according to the above (10) or (11), wherein the cooling is performed while maintaining a pressurized state by the tool.

(13) The compression molding method according to any one of the above (9) to (12), wherein a difference in material temperature between the first part and the second part is 20 ° C. or more.

(14) a plurality of molds each having a first portion capable of holding a first temperature and a second portion capable of holding a second temperature different from the first temperature; A compression molding method for compressing and molding the molding material using a tool for compressing the molding material filled in the mold, wherein a first step of filling the molding material into a predetermined mold at a supply position. And a second step of moving the mold to a molding position and performing compression molding. In the second step, the molding material located in the first portion is transferred to the second portion. A compression molding method characterized by relatively moving and giving a temperature change to a molding material before and after this movement.

(15) A plurality of molds having a first portion for heating the molding material and a second portion for cooling the heated molding material, and compressing the molding material filled in the mold. And a compression molding method for compressing and molding a molding material using a tool that performs a first step of filling the molding material into a predetermined mold at a material supply position, and moving the mold to the molding position. And
A compression molding process, wherein the molding material is compressed while being heated in the first portion, and then relatively moved to the second portion and cooled. Method.

(16) A plurality of molds having a first portion for heating the molding material and a second portion for cooling the heated molding material, and compressing the molding material filled in the mold. And a compression molding method for compressing and molding a molding material using a tool that performs a first step of filling the molding material into a predetermined mold at a material supply position, and moving the mold to the molding position. And
A second step of performing compression molding, wherein after the molding material is heated in the first portion, the molding material is relatively moved to the second portion for compression molding and cooling. Molding method.

(17) The compression molding method according to the above (15) or (16), wherein the cooling is performed while maintaining a pressurized state by the tool.

(18) The compression molding method according to any one of the above (14) to (17), wherein a difference in material temperature in the second step is 20 ° C. or more.

(19) The compression molding method according to any one of the above (14) to (18), wherein the molding material is filled into another mold during the execution of the second step.

(20) During the execution of the second step, the molded article already molded is removed from another mold.
4) The compression molding method according to any one of (19) to (19).

(21) The compression molding method according to any one of the above (9) to (20), wherein material removal of the molded body is performed from the side having a lower temperature in the first portion and the second portion.

(22) The compression molding method according to any one of the above (9) to (21), wherein the molding material is quantified using a quantitative feeder and filled.

(23) The compression molding method according to any one of the above (9) to (22), wherein the molding material is a composition for producing a bonded magnet.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a compression molding apparatus and a compression molding method of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

1 to 5 are sectional side views schematically showing an embodiment of the compression molding apparatus of the present invention. Note that the vertical direction in FIGS. 1 to 5 will be described as “axial direction”.

The compression molding apparatus 1 shown in these figures is a compression molding apparatus for compression-molding a bonded magnet, and includes a compression molding die 2 and a molding material 15 filled in the die 2. And a tool (punch) for compressing.

The mold 2 is composed of three parts along the axial direction. That is, the mold 2 includes a first portion 3 that can hold a first temperature and a second portion 3 that is different from the first temperature.
And a heat insulating part 4 located between the first part 3 and the second part 5. In the present embodiment, the first part 3 is a heating unit for heating the molding material 15, and the second part 5 is a cooling unit for cooling the heated molding material 15.

A molding space 21 is formed in the first part 3, the heat insulating part 4, and the second part 5 of the mold 2 so as to penetrate them. The molding space 21 has a shape corresponding to the shape of the molded body to be molded, and in this embodiment, has a columnar (solid) shape. However, the shape of the molding space 21 (the shape of the molded body) is not limited to this. ), A flat plate, a curved plate, and the like.

The first part 3 is provided with a heater 9 for heating it. In the illustrated configuration, a rod-shaped heater is used, but the configuration of the heater 9 is not limited to this. The operation of the heater 9 causes the first portion 3
Is heated to a predetermined temperature described later.

Further, a refrigerant pipe 10 is buried in the second portion 5 to cool it. This refrigerant pipe 10
, A coolant such as water, air, or the like is supplied and distributed by a coolant supply unit (not shown). By the flow of the refrigerant, the second portion 5 is set (cooled) to a predetermined temperature described later.

The heat insulating portion 4 includes a first portion 3 and a second portion 5
It has a function of blocking the transfer of heat between them, and is made of, for example, ceramics, a resin sheet, an air gap, or a combination thereof. By providing such a heat insulating part 4, heat loss can be reduced and efficient heating and cooling can be performed.

It is to be noted that, different from the illustration, a configuration in which a heating jig such as a heater or a cooling jig such as a refrigerant pipe is provided on the outer peripheral portion of the mold 2 may be employed.

The tool (punch) 6 comprises an upper punch 7 for pressing the molding material 15 from opposite directions and a lower punch 8. Each of the upper punch 7 and the lower punch 8 is configured to be relatively movable in the axial direction within the molding space 21 with respect to the mold 2. In the present embodiment, the upper punch 7 and the lower punch 8 are each configured to move in the axial direction by a drive mechanism (not shown) with respect to the mold 2 whose movement in the axial direction is fixed.

The outer diameter of the upper punch 7 and the lower punch 8 is substantially equal to the inner diameter of the mold 2 (= the diameter of the molding space 21),
Or it is set to a slightly smaller value.

A pressing surface 71 for pressing the molding material 15 is provided on each end of the upper punch 7 and the lower punch 8.
81 are formed. The shape (the cylindrical shape in the present embodiment) of the molded body is regulated by the pressing surfaces 71 and 81 and the inner peripheral surface of the molding space 21.

The pressing surfaces 71 and 81 may be any of flat surfaces, curved surfaces as desired, surfaces having protrusions and depressions, and surfaces having grooves or the like.

The molding material 15 in this embodiment is a composition (compound) for producing a bonded magnet. This composition is a mixture or kneaded product of a magnet powder and a binding resin (organic binder) or a granulated product obtained by granulating or sizing the mixture.

Examples of the magnet powder include ferrites such as Ba ferrite and Sr ferrite, and Sm-Co
And R-TM-B (R is a rare earth element, TM is a transition metal), Sm-Fe-N type and other rare earth magnet powders. The average particle size of the magnet powder is 0.5 ~ 100μm
Is preferably about 1 to 50 μm.

The binding resin may be either a thermoplastic resin or a thermosetting resin. Examples of the thermoplastic resin include a polyamide resin, an aromatic polyester resin, a polyphenylene sulfide resin, a thermoplastic polyimide resin, a polyethylene resin, a polypropylene resin, and a polyolefin resin such as an ethylene-vinyl acetate copolymer. Examples of the resin include an epoxy resin and a phenol resin.

The content of the binder resin in the composition is not particularly limited, but is preferably about 1 to 10% by weight, more preferably about 1 to 8% by weight.
More preferably, it is about 1.5 to 5% by weight. If the content of the binder resin is too large, the magnetic properties (particularly, the maximum magnetic energy product) cannot be improved. On the other hand, when the content of the binding resin is too small, the moldability is reduced.

Further, the composition may contain an antioxidant. As the antioxidant, any antioxidant can be used as long as it can prevent or suppress the oxidation of the magnet powder and the like, for example, amine compounds, amino acid compounds, nitrocarboxylic acids, hydrazine compounds, cyanide compounds, sulfides and the like. A chelating agent which forms a chelate compound with respect to the metal ion, particularly the Fe component, is preferably used.

In addition, plasticizers such as higher fatty acids and fatty acid salts, lubricants such as silicone oil and wax, silica powder, and the like, in order to facilitate dispersion of the magnet powder and the resin component during kneading and to improve the moldability of the kneaded product. And a molding aid such as a copolymer.

In the case of kneading the magnetic powder, the binder resin, and preferably the antioxidant as described above, the kneading is performed using a kneader such as a twin-screw extruder, a roll-type kneader or a kneader. .

This kneading is preferably carried out at a temperature not lower than the heat distortion temperature of the binder resin used (measured by a method according to ASTM D648), more preferably at a temperature not lower than the melting point of the binder resin used.

Further, the kneaded material can be granulated or sized to obtain a granular material having a predetermined particle size. The method of granulation or sizing is not particularly limited, but is preferably performed by pulverizing the kneaded material. This pulverization is performed using, for example, a ball mill, a vibration mill, a crusher, a jet mill, a pin mill, or the like.

The average particle size of the granular material is not particularly limited, but is preferably about 10 μm to 3 mm, and is preferably about 20 μm.
About 2 mm, more preferably 50 μm to 1.5
More preferably, it is about mm. When the average particle size of the granular material is 3 mm or more, the filling amount of the granular material into the mold 2 is delicate when the size of the bonded magnet to be molded is small, that is, when the size of the molding space 21 of the mold 2 is small. It is difficult to adjust the bond magnet and the quantitative property is poor, so that the dimensional accuracy of the bonded magnet cannot be improved. On the other hand, granules having an average particle size of less than 10 μm may be difficult or troublesome to produce (granulate), and if the average particle size is too small, the porosity of the resulting bonded magnet increases. Show the trend.

Such a granular material may have a certain degree of variation in the particle size, but preferably has a uniform particle size. Thereby, the variation in filling the mold 2 is reduced,
A bonded magnet with low porosity and high dimensional accuracy can be obtained.

Next, a first compression molding method using the compression molding apparatus 1 will be described with reference to FIGS.
Hereinafter, the molding material 15 to be filled into the mold 2 will be described using the above-mentioned granular material as a representative example.

<A-1> As shown in FIG. 1, the upper punch 7 is raised and is separated from the molding space 21. The lower punch 8 is moved so that the pressing surface 81 is located at the first portion 3.

<A-2> As shown in FIG. 2, a predetermined amount of the molding material 15 is filled (supplied) into the molding space 21. At this time, the weighing and filling of the molding material 15 may be performed by a scouring method so that the upper surface of the molding material 15 coincides with the upper end opening of the molding space 21 (with a constant volume). It is preferable that the molding material 15 is quantified and filled by using the above method. Thereby, the accuracy of the filling amount of the molding material 15 is increased, and the dimensional accuracy of the obtained bonded magnet is improved.

Examples of the quantitative feeder include those equipped with an electronic balance and a load cell. For example, JP-A-62-211518 and JP-A-62-2115.
19, JP-A-62-231121, JP-A-62-235115, JP-A-63-47216, JP-A-63-98523, JP-A-63-2
The apparatuses described in JP-A-52816, JP-A-3-88614, and JP-A-7-291203 can be used.

<A-3> As shown in FIG. 3, the upper punch 7 is lowered, and the pressing surface 71 and the pressing surface 8 of the lower punch 8 are moved downward.
1, the molding material 15 is compression-molded.

At this time, the operation of the heater 9 causes the mold 2 to move.
Is heated to a desired temperature (first temperature). Thereby, the molding material 15 is warm-formed. This first temperature is set, for example, as follows.

When the filling molding material 15 contains a thermoplastic resin as a binder resin, the temperature is set such that the thermoplastic resin is in a softened or molten state.

More specifically, the temperature is preferably higher than the thermal deformation temperature of the thermoplastic resin to be used, and more preferably, it is higher than the melting point of the thermoplastic resin to be used. It is more preferable that the temperature is set to a predetermined temperature in the range up to about ° C.
More preferably, the temperature is set to a predetermined temperature in the range of about 50) ° C.

For example, when the thermoplastic resin used is a polyamide resin (melting point: 178 ° C.), a particularly preferable material temperature (first temperature) during molding is 180 to 350.
℃.

When the filling molding material 15 contains a thermosetting resin as a binder resin, the temperature is set so that the thermosetting resin is in a softened or molten state and the curing is not completed within the molding time. You.

More specifically, the melting temperature of the thermosetting resin to be used is preferably from (melting temperature + 200) ° C.
(Melting temperature + 150) ° C. is more preferable.

For example, if the thermosetting resin used has a melting temperature of 6
In the case of an epoxy resin having a curing condition of 0 ° C. and a curing condition of 200 ° C. for 1 hour, a particularly preferable material temperature (first temperature) at the time of molding is about 60 to 260 ° C.

By molding at the first temperature as described above, the fluidity of the molding material 15 in the mold 2 (in the first portion 3) is improved, and it is needless to say that the molding material 15 has a columnar or block shape. It has low porosity, high mechanical strength, good and stable, even if it has a thin part such as a cylinder (ring), flat plate, curved plate, etc., small or long one. Shape,
Dimensions can be mass-produced.

The molding pressure in the compression molding in this step is preferably 60 kgf / mm ² or less, more preferably ² kgf / mm ² or less.
About 50 kgf / mm ² , more preferably 5 to 40 kgf / mm ²
Degree. In the present invention, since the molding is performed at the first temperature as described above, the bonded magnet having the advantages as described above can be molded (shaped) even at such a relatively low molding pressure.

The compression molding may be performed in a magnetic field (the orientation magnetic field is, for example, 5 to 20 kOe, and the orientation direction may be any of vertical, horizontal, and radial directions) or in a non-magnetic field. These are appropriately selected according to conditions such as the composition and properties of the magnet powder.

<A-4> As shown in FIG. 4, the upper punch 7 and the lower punch 8 are moved down (moved) so that the molding material (molded body) 15 is located at the second portion 5.

At this time, the second portion 5 is cooled to a desired temperature (second temperature) lower than the first temperature by the refrigerant flowing through the refrigerant pipe 10. Thereby, the molding material 15 is cooled.

The movement of the upper punch 7 and the lower punch 8 is performed while the pressurized state of the molding material 15 is maintained, that is, while the molding pressure applied to the molding material 15 is maintained within the above range. Preferably. Less than,
This is called "cooling under pressure".

By performing such cooling under pressure,
Since the compact has a low porosity state at the time of compression molding as it is, a bonded magnet having low porosity, high dimensional accuracy, and excellent magnetic properties can be obtained.

The second temperature (decompression temperature) is used to reduce the porosity and improve the dimensional accuracy of the obtained bonded magnet.
Preferably, the temperature is as low as possible.

That is, when the molding material 15 contains a thermoplastic resin as the binder resin, the second temperature is preferably the melting point of the thermoplastic resin to be used or a temperature lower than the melting point of the thermoplastic resin to be used. The temperature is more preferably (softening point) or lower.

In the case where the molding material 15 contains a thermosetting resin as a binder resin and is subjected to a curing treatment in a later step, the second temperature is preferably a melting temperature of the thermosetting resin or a temperature lower than the melting temperature. preferable.

The difference between the first temperature and the second temperature is preferably at least 20 ° C., more preferably at least 50 ° C. The greater the temperature difference, the greater the effect of reducing the porosity and improving the dimensional accuracy of the resulting bonded magnet.

When the content of the magnet powder is relatively large, it is easy to obtain a bonded magnet having a low porosity even if the second temperature is set higher. Therefore, for example, when the content of the magnet powder in the molding material 15 is, for example, 94 wt% or more, the second
The porosity can be reduced even when the temperature is set to a temperature near the melting point of the binder resin (thermoplastic resin) to be used or a temperature higher than or equal to the melting point (up to about + 10 ° C.).

The cooling under pressure may be performed after the pressure during the compression molding is once released or relaxed, but the cooling under pressure is continuously performed without releasing the pressure during the compression molding. It is preferable for simplification and improvement of dimensional accuracy.

The pressure during cooling under pressure may be constant or may vary, but it is preferable that the pressure is kept constant at least up to the melting point (particularly the heat deformation temperature) of the binder resin used. When the pressure at the time of cooling under pressure changes, for example, it may include a pattern in which the pressure increases or decreases continuously or stepwise.

The pressure during cooling under pressure (when the pressure changes with time, the average pressure thereof) is preferably equal to or less than the molding pressure during compression molding.

In the present invention, after cooling under pressure (after depressurization), it goes without saying that the upper punch 7 may be raised and cooling may be continued without pressure (under normal pressure). Also,
After cooling under non-pressurization, cooling under pressure may be performed again.

Cooling rate during such cooling, especially cooling under pressure (if the cooling rate changes over time, its average value)
Is not particularly limited, but is preferably 0.5 to 100 ° C / sec, more preferably 1 to 80 ° C / sec. If the cooling rate is too high, rapid shrinkage due to cooling may cause fine cracks inside the molded body, which may lead to a decrease in mechanical strength. When the material is removed from the material, strain or deformation due to stress relaxation may occur, and the dimensional accuracy may decrease. On the other hand, if the cooling rate is too slow, the molding cycle time increases, and the productivity decreases.

<A-5> The bonded magnet molded body obtained as described above is taken out of the mold 2 (material removal). That is, as shown in FIG. 5, the upper punch 7, the magnet molded body 16,
By lowering the lower punch 8 as it is, the molded body 16 is discharged from the molding space 21 to below the mold 2. At this time, it is preferable that the lower punch 8 does not press the molded body 16.

When the molded body 16 comes out of the mold 2,
The upper punch 7 is lifted and separated from the molded body 16. By pressing and moving the formed body 16 on the pressing surface 81 of the lower punch 8 in the lateral direction (the direction of the arrow in the drawing), the material of the formed body 16 is removed.

After the removal, the lower punch 8 is raised and returned to the original position (the position shown in FIG. 1).

As described above, the first portion 3 and the second portion 5
By removing the material from the one having the lower temperature, the molded body 16 is not heated again and is not deformed, which contributes to the improvement of the dimensional accuracy.

Needless to say, the removal of the molded body 16 may be performed by moving the lower punch 8 upward in the figure of the mold 2.

<A-6> When a thermosetting resin is used as the binding resin, the molded body 16 from which the material has been removed is subjected to a treatment (curing) for curing the uncured thermosetting resin. . This processing is performed by subjecting the molded body 16 to a heat treatment at a predetermined temperature and a predetermined time at which the thermosetting resin can be cured.

Next, the second compression molding method using the compression molding apparatus 1 will be described focusing on differences from the first compression molding method.

<A'-1> Same as <A-1>.

<A′-2> Similar to the above <A-1>,
Filling a predetermined amount of the molding material 15 into the molding space 21 (supply)
I do. At this time, the operation of the heater 9 causes the first
Is heated to a desired temperature (first temperature).
Thereby, the filled molding material 15 is heated to a desired temperature (first temperature).

<A'-3> The lower punch 8 is lowered (moved).
Then, the heated uncompressed molding material 15 is positioned in the second portion 5.

Next, similarly to the above <A-3>, the upper punch 7 is lowered, and the molding material 15 is compression-molded in a magnetic field or without a magnetic field. The molding material 15 has already been heated to the first temperature in the previous step, so that warm molding is performed.

<A′-4> Before and after the compression molding,
A refrigerant is supplied to the refrigerant pipe 10 to cool the second portion 5.
Thus, the molding material 15 is cooled to a desired temperature (second temperature).

At this time, the cooling is preferably performed under pressure, that is, while the pressurized state of the molding material 15 is maintained by the upper punch 7 and the lower punch 8.

<A'-5> The same as <A-5>.

<A'-6> Same as <A-6>.

According to the apparatus and the method of the present invention as described above, the molding material 15 is separated into the first portion 3 and the second portion 3 having different temperatures.
By moving between the portions 5, warm molding and cooling of the molding material 15 can be performed continuously in the same mold 2, so that molding is easy, the cycle time of molding is short, Therefore, productivity is greatly improved.

FIG. 6 is a plan view showing another embodiment of the compression molding apparatus of the present invention, and FIGS. 7 to 13 are sectional side views showing a state where the compression molding apparatus shown in FIG. 6 is expanded. . The vertical direction in FIGS. 7 to 13 will be described as “axial direction”.

The compression molding device 11 shown in these figures is a compression molding device for compression molding a bonded magnet. Hereinafter, the configuration of the compression molding device 11 will be described focusing on differences from the compression molding device 1.

The compression molding device 11 includes a disk-shaped support base 12.
And a plurality (3 in this embodiment) installed on the support table 12.
Dies) 2a, 2b, 2c and the respective dies 2a, 2b,
And a tool (punch) 6 for compressing the molding material 15 filled in 2c.

The support base 12 is configured to rotate about the rotation shaft 13 in, for example, a counterclockwise direction in FIG.

Each of the molds 2a, 2b and 2c has the same configuration as that of the mold 2. That is, the mold 2
In each of a, 2b, and 2c, a first portion 3 and a second portion 5 are arranged in the axial direction via a heat insulating portion 4, and the first portion 3 is heated by a heater 9 to a first temperature. Heated to
The second portion 5 is subjected to a second flow by the refrigerant flowing through the refrigerant pipe 10.
It is designed to be cooled to the temperature.

Adjacent ones of the dies 2a, 2b, 2c are connected to each other by a connecting member 14, and the positional relationship between the dies 2a, 2b, 2c is fixed.

If the positional relationship between the dies 2a to 2c is fixed, such a connecting member 14 is not always necessary.

The tool (punch) 6 includes one upper punch 7
And three lower punches 8a, 8b, 8c inserted into the molding spaces 21 of the dies 2a, 2b, 2c, respectively. The lower punches 8a, 8b, 8c are respectively
This is similar to the lower punch 8.

The center axis of the upper punch 7 is
The molds 2a, 2b, and 2c mounted on the rotary shaft 13 are installed at positions such that the dies 2a, 2b, and 2c are positioned on the locus of the central axis of the molding space 21 generated when the molds 2a and 2b rotate about the rotation shaft 13. In this case, the upper punch 7 can only move in the axial direction.

FIGS. 6 to 10 show a state in which the molding space 21 of the mold 2b is located directly below the upper punch 7. FIG.
FIG. 13 to FIG. 13 show a state in which the support base 12 is rotated by 120 ° counterclockwise in FIG. 6 and the molding space 21 of the mold 2 a is located directly below the upper punch 7.

The position of the mold 2a in FIGS.
This is the material supply position 17 where the molding material 15 is filled into the molding space 21 of the mold, and the position of the mold 2b in FIG.
This is a molding position 18 where compression molding is performed. In addition, the position of the mold 2c in the figure is a material removal position 19 where the compression molded body 16 is removed. Each mold 2a, 2b, 2c
6, respectively, by the counterclockwise rotation of the support base 12 in FIG. 6, the feeding position 17, the forming position 18, and the removing position 19.
Can be sequentially moved to

In the compression molding apparatus 11, the number of dies may be two or four or more. Also,
In the present embodiment, each mold is configured to rotate and move. However, for example, a configuration in which each mold linearly moves by a conveyor such as a conveyor may be used.

Next, a third compression molding method using the compression molding device 11 will be described with reference to FIGS.

<B-1> As shown in FIGS. 6 and 7, the upper punch 7 is raised and supported so that the molding space 21 of the mold 2b is located immediately below the upper punch 7 (molding position 18). The table 12 is rotated. Also, the lower punch 8a,
8b and 8c, the pressurizing surfaces 81 of the molds 2a and 2c
b and 2c are moved so as to be located in the first portion 3.

The mold 2b is preferably filled (supplied) with the molding material 15 preferably by the above-described quantitative feeder.

<B-2> As shown in FIG. 8, the upper punch 7 is lowered, and the molding material 15 is compression molded between the pressing surface 71 and the pressing surface 81 of the lower punch 8b.

At this time, the operation of the heater 9 causes the mold 2 to move.
The first portion 3 of b is heated to the first temperature as described above. Thereby, the molding material 15 is warm-formed.

The setting of the molding pressure and the molding in a magnetic field or in the absence of a magnetic field are the same as described above.

<B-3> As shown in FIG. 9, the upper punch 7 and the lower punch 8b are lowered (moved) so that the molding material (molded body) 15 is positioned at the second portion 5 of the mold 2b. To

At this time, the second portion 5 of the mold 2b is cooled to the second temperature by the refrigerant flowing through the refrigerant pipe 10. Thereby, the molding material 15 is cooled.
This cooling is preferably the above-mentioned cooling under pressure.

The preferred cooling rate for such cooling, particularly for cooling under pressure, is the same as described above.

<B-4> Steps <B-2> and / or
Alternatively, in the same manner as in the step <B-3>, the molding material 15 is charged (supplied) to the mold 2a at the supply position 17 in the same manner as described above.

The supply of the material to the mold 2a corresponds to a preparation step for the next compression molding. The supply of the material is performed in steps <B-2> and <B-2>.
By performing at least one of B-3> in time, the manufacturing time can be shortened as a whole, which contributes to an improvement in productivity.

<B-5> As shown in FIG. 10, the upper punch 7 is raised to be separated from the molding space 21 of the mold 2b.

<B-6> The support base 12 is rotated counterclockwise in FIG. 6 by 120 °, and the molds 2 a, which have been located at the supply position 17, the molding position 18, and the removal position 19, respectively. 2b and 2c are moved to the forming position 18, the material removing position 19 and the material supplying position 17. This results in the state shown in FIG.

<B-7> As shown in FIG. 12, the upper punch 7 is lowered, and the molding material 15 in the mold 2a is compression molded between the pressing surface 71 and the pressing surface 81 of the lower punch 8a. I do.

At this time, the operation of the heater 9 causes the mold 2 to move.
The first portion 3a is heated to the first temperature as described above. Thereby, the molding material 15 is warm-formed.

The setting of the molding pressure and the molding in a magnetic field or in the absence of a magnetic field are the same as described above.

<B-8> As shown in FIG. 13, the upper punch 7 and the lower punch 8a are lowered (moved) so that the molding material (molded body) 15 is positioned at the second portion 5 of the mold 2a. To

At this time, the second portion 5 of the mold 2a is cooled to the second temperature by the refrigerant flowing through the refrigerant pipe 10. Thereby, the molding material 15 is cooled.
This cooling is preferably the above-mentioned cooling under pressure.

The preferred cooling rate for such cooling, particularly for cooling under pressure, is the same as described above.

<B-9> The steps <B-7> and / or
Alternatively, the mold 2c at the material supply position 17 is filled with the molding material 15 (material supply) in the same manner as described above, overlapping the process <B-8>.

The supply of the material to the mold 2c corresponds to a preparation step for the next compression molding. The supply of the material is performed in steps <B-7> and <B-7>.
B-8>, the manufacturing time can be shortened as a whole, and the productivity can be improved.

<B-10> The removal position 19 is overlapped with the step <B-7> (or the step <B-8>).
Is removed from the mold 2b in the molding space 21 in the molding space 21. That is, as shown in FIG.
By lowering the lower punch 8b in the mold 2b,
6 is discharged from the molding space 21 and then the exposed molded body 1 is exposed.
6 by moving the molded body 16 in the lateral direction.
Is removed.

As described above, the first portion 3 and the second portion 5
By removing the material from the one having the lower temperature, the molded body 16 is not heated and deformed, thereby contributing to improvement in dimensional accuracy.

The molded body 16 was removed from the lower punch 8b.
May be moved upward by moving the mold 2b in the figure.

As described above, the material removal from the mold 2b is performed in the step <
B-7> (or step <B-8>) is performed in a time overlapping manner, whereby the manufacturing time can be shortened as a whole, which contributes to an improvement in productivity.

After the material is removed, the lower punch 8b is returned to the original position (the position shown in FIG. 13) for the next molding.

<B-11> When a thermosetting resin is used as the binding resin, the molded body 16 from which the material has been removed is subjected to a process (curing) of curing the uncured thermosetting resin. . This processing is performed by subjecting the molded body 16 to a heat treatment at a predetermined temperature and a predetermined time at which the thermosetting resin can be cured.

<B-12> Thereafter, the support base 12 is rotated in the counterclockwise direction in FIG. 6 by 120 °, and the steps <B-5> to <B− By repeating the same steps as <11>, a bonded magnet molded body can be manufactured continuously.

Next, a fourth compression molding method using the compression molding apparatus 11 will be described, focusing on differences from the third compression molding method. The fourth compression molding method includes the first compression molding method.
The relationship between the second compression molding method and the third compression molding method is similarly applied to the third compression molding method.

That is, <B-1>, <B-4>, <B
-9>, the heater 9 is operated to heat the first portion 3 of the mold, and the filled molding material 15 is heated to a desired temperature (first temperature). I do.

Next, the lower punch is lowered to move the heated molding material 15 to the second portion 5 in an uncompressed state, and subsequently, the upper punch is lowered to lower the molding material 15.
Is compression molded in the second part 5. Further, before and after this, a coolant is supplied to the coolant pipe 10 to cool the second portion 5, and the molding material 15 is cooled to a desired temperature (second temperature), preferably cooled under pressure.

The other points are the same as in the third compression molding method.

According to the apparatus and method of the present invention as described above, the molding material 15 is formed by the first part 3 and the second part 3 having different temperatures.
By moving between the portions 5, warm molding and cooling of the molding material 15 can be performed continuously in the same mold 2, so that molding is easy, the cycle time of molding is short, Therefore, productivity is greatly improved. In particular, by using a plurality of dies and performing different processes on them in parallel, productivity is remarkably improved.

Further, according to the apparatus and method of the present invention, a bonded magnet having the following excellent characteristics can be manufactured. That is, the porosity of the bonded magnet is low, preferably 4.5% (vol%) or less, more preferably 3.5%.
Or less, more preferably 2.0% or less. Thus, since the porosity is low (= high density),
It has high mechanical strength, excellent corrosion resistance, high dimensional accuracy, little dimensional variation even in mass production, and excellent dimensional stability.

Further, the bonded magnet produced by the apparatus and method of the present invention has excellent magnetic properties. In particular, the bonded magnet is an isotropic magnet due to the composition of the magnet powder and the large content of the magnet powder. However, it has excellent magnetic properties.

As described above, the compression molding apparatus and the compression molding method of the present invention have been described based on the embodiments shown in the accompanying drawings, but the present invention is not limited to these.

In the illustrated embodiment, warm forming and cooling are performed in one mold, but the present invention is not limited to this, and the following steps may be performed in the mold.

Warm forming at high temperature-heat treatment at low temperature Warm forming at high temperature-heat treatment at low temperature-normal temperature Warm forming at high temperature-warm forming at low temperature-cooling-Warm forming- Cooling-Heating resin curing-Warm forming-Heating (higher temperature) resin curing-Cold forming-Heating resin curing-Cold or warm forming-Heating resin curing-Cooling-Heat treatment at high temperature-Low temperature Cold pressing-Heat treatment at high temperature-Hot forming at low temperature-Cooling-Cold pressing-Hot forming at high temperature-Cooling-Cold pressing-Temperature at high temperature In the apparatus of the present invention, the first portion 3 and the second portion 5
May be reversed.

In the illustrated configuration, the mold has a three-layer structure including the first portion 3, the heat insulating portion 4, and the second portion 5, but the mold is not limited to this, and may have four or more layers. In this case, for example, a portion (cooling unit) for applying a temperature lower than the first temperature can be provided as a third portion on the first portion 3.

The present invention can be applied to other than the production of bonded magnets, such as the production of dust magnets, the production of molded articles subjected to firing and sintering, and the production of resin molded articles. .

[0156]

As described above, according to the present invention, a high-quality molded product can be easily and quickly manufactured, thereby contributing to an improvement in productivity.

In particular, when applied to the production of a bonded magnet, a bonded magnet having high mechanical strength, excellent magnetic properties, and high dimensional accuracy can be produced with high production efficiency.

[Brief description of the drawings]

FIG. 1 is a sectional side view schematically showing an embodiment of a compression molding apparatus of the present invention.

FIG. 2 is a sectional side view schematically showing an embodiment of the compression molding apparatus of the present invention.

FIG. 3 is a sectional side view schematically showing an embodiment of the compression molding apparatus of the present invention.

FIG. 4 is a sectional side view schematically showing an embodiment of the compression molding apparatus of the present invention.

FIG. 5 is a sectional side view schematically showing an embodiment of the compression molding apparatus of the present invention.

FIG. 6 is a plan view showing another embodiment of the compression molding apparatus of the present invention.

7 is a sectional side view showing a state where the compression molding apparatus shown in FIG. 6 is expanded.

8 is a sectional side view showing a state where the compression molding apparatus shown in FIG. 6 is expanded.

9 is a sectional side view showing a state where the compression molding apparatus shown in FIG. 6 is expanded.

10 is a sectional side view showing a state where the compression molding device shown in FIG. 6 is expanded.

11 is a sectional side view showing a state where the compression molding apparatus shown in FIG. 6 is expanded.

12 is a sectional side view showing a state where the compression molding apparatus shown in FIG. 6 is expanded.

13 is a sectional side view showing a state where the compression molding device shown in FIG. 6 is expanded.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compression molding apparatus 2 Die 2a, 2b, 2c Die 21 Molding space 3 First part 4 Heat insulation part 5 Second part 6 Tool 7 Upper punch 71 Pressing surface 8 Lower punch 8a, 8b, 8c Lower punch 81 Addition Compression surface 9 Heater 10 Refrigerant tube 11 Compression molding device 12 Support base 13 Rotating shaft 14 Connecting member 15 Molding material 16 Molded body 17 Feeding position 18 Molding position 19 Molding position 19

Claims (23)

[Claims] 1. A mold for compression molding, and a tool for compressing a molding material filled in the mold, wherein the tool comprises:
A compression molding apparatus configured to be relatively movable with respect to the mold, wherein the mold includes a first portion capable of maintaining a first temperature, and a second portion different from the first temperature. And a second portion capable of maintaining the temperature of the tool, and the first portion and the second portion are arranged along a direction of relative movement between the tool and the mold. A compression molding apparatus characterized by the above-mentioned. 2. A mold for compression molding, and a tool for compressing a molding material filled in the mold, wherein the tool comprises:
A compression molding apparatus configured to be relatively movable with respect to the mold, wherein the mold includes a first portion that heats a molding material, and a second portion that cools the heated molding material. And the first part and the second part are arranged along a direction of relative movement between the tool and the mold. 3. The compression molding apparatus according to claim 1, wherein the tool includes an upper punch and a lower punch that press the molding material from directions opposite to each other. 4. A method according to claim 1, further comprising: a plurality of compression molds; and a tool for compressing a molding material filled in the mold, wherein the tool is movable relative to the mold. It is a compression molding apparatus configured, wherein each of the molds is capable of maintaining a first temperature.
And a second part capable of maintaining a second temperature different from the first temperature, and the first part and the second part are the tool and the mold. Each of the dies can move between a material supply position for filling a molding material into the dies and a molding position for performing compression molding by the tool. A compression molding apparatus characterized by being configured as described above. 5. A method comprising: a plurality of compression molds; and a tool for compressing a molding material filled in the mold, wherein the tool is movable relative to the mold. In the compression molding apparatus configured, each of the molds has a first portion for heating the molding material, and a second portion for cooling the heated molding material, and The first part and the second part are arranged along the direction of relative movement between the tool and the mold, and each of the molds is configured to supply a molding material into the mold. A compression molding apparatus configured to be movable between a material position and a molding position at which compression molding is performed by the tool. 6. The tool according to claim 4, wherein the tool has an upper punch and a lower punch for pressing a molding material from directions opposite to each other, one of which is provided at the molding position and the other moves with the mold. 6. The compression molding apparatus according to 5. 7. The compression molding apparatus according to claim 1, wherein the first part and the second part are arranged via a heat insulating part. 8. The compression molding apparatus according to claim 1, wherein the molding material is a composition for producing a bonded magnet. 9. A first portion capable of maintaining a first temperature;
Compression molding of a molding material using a mold having a second portion capable of maintaining a second temperature different from the first temperature, and a tool for compressing the molding material filled in the mold. Compression molding method, wherein a molding material located in the first portion is relatively moved to the second portion, and a temperature change is given to the molding material before and after the movement. Molding method. 10. A mold having a first portion for heating the molding material, a second portion for cooling the heated molding material, and a tool for compressing the molding material filled in the mold. A compression molding method for compressing and molding a molding material, wherein the molding material is compressed while being heated in the first portion, and then relatively moved to the second portion for cooling. Compression molding method. 11. A mold having a first portion for heating a molding material, a second portion for cooling the heated molding material, and a tool for compressing the molding material filled in the mold. A compression molding method for compressing and molding a molding material using the method, wherein after the molding material is heated in the first portion, the molding material is relatively moved to the second portion for compression molding and cooling. Characteristic compression molding method. 12. The compression molding method according to claim 10, wherein the cooling is performed while maintaining a pressurized state by the tool. 13. A material temperature difference between the first part and the second part is 20 ° C. or more.
The compression molding method according to any one of the above. 14. A plurality of molds each having a first portion capable of maintaining a first temperature and a second portion capable of maintaining a second temperature different from the first temperature, and the mold. A compression molding method for compressing and molding the molding material using a tool for compressing the molding material filled therein, comprising: a first step of filling the molding material into a predetermined mold at a supply position; Moving the mold to a molding position and performing compression molding. In the second step, the molding material located in the first portion is moved relative to the second portion. A compression molding method characterized in that the molding material moves in a predetermined manner and a temperature change is applied to the molding material before and after the movement. 15. A plurality of molds having a first part for heating the molding material and a second part for cooling the heated molding material, and compressing the molding material filled in the mold. A compression molding method for compressing and molding a molding material using a tool, comprising: a first step of filling the molding material into a predetermined mold at a material supply position; and moving the mold to the molding position. And a second step of performing compression molding. After the molding material is compressed while being heated in the first portion, the molding material is relatively moved to the second portion and cooled. Molding method. 16. A plurality of molds having a first part for heating the molding material and a second part for cooling the heated molding material, and compressing the molding material filled in the mold. A compression molding method for compressing and molding a molding material using a tool, comprising: a first step of filling the molding material into a predetermined mold at a material supply position; and moving the mold to the molding position. And a second step of performing compression molding. After the molding material is heated in the first portion, the molding material is relatively moved to the second portion, compression-molded, and cooled. Compression molding method. 17. The compression molding method according to claim 15, wherein the cooling is performed while maintaining a pressurized state by the tool. 18. The compression molding method according to claim 14, wherein the difference between the material temperatures in the second step is 20 ° C. or more. 19. The compression molding method according to claim 14, wherein the molding material is filled into another mold during the execution of the second step. 20. The compression molding method according to claim 14, wherein during the execution of the second step, a molded body that has already been molded is removed from another mold. 21. The molding material is removed from the lower temperature side of the first part and the second part.
0. The compression molding method according to any one of the above items. 22. The compression molding method according to claim 9, wherein the molding material is quantified and filled using a quantitative feeder. 23. The compression molding method according to claim 9, wherein the molding material is a composition for producing a bonded magnet.