JP2018047492A - Powder molding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder molding device capable of restraining variation in the quality of a molding body even in continuous molding.SOLUTION: A powder molding device 1 comprises a side die 4 having a first through-hole 4a enclosing a side of a powder material P, an upper die 2 slidably fitted with an inner wall 4aA of the first through-hole 4a and pressurizing the powder material P from above, a lower downward die 5 fixedly arranged so as to be fitted with the inner wall 4aA of the first through-hole 4a in a lower part of the first through-hole 4a and having a second through-hole 5a inside, a floating downward die 3 slidably fitted to an inner wall 5aA of the second through-hole 5a and adding a floating load from below to the powder material P, a floating load imparting mechanism 6 for imparting floating load, a temperature detection unit 10 for detecting the temperature of the powder material P, and a control unit 11 for controlling the floating load imparting mechanism 6 so that the floating load is maintained at a preset value. The control unit 11 lowers the preset value when the temperature of the detected powder material P has risen to a reference temperature.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a powder molding apparatus.

  2. Description of the Related Art A powder forming apparatus that compresses and forms a powder material filled in a space surrounded by a mold is known. In Patent Document 1, a lateral die (die) that surrounds the side of the powder material, an upper die (fixed upper punch and floating upper punch) that pressurizes the powder material from above, and a side die are fixedly disposed. A lower lower mold (fixed lower punch) and a floating lower mold (floating lower punch) that slidably fits with the inner wall of the through hole of the lower lower mold and applies a floating load to the powder material from below. A powder molding apparatus is described.

JP-A-6-025706

  FIG. 8 is a diagram showing a schematic configuration of the powder molding apparatus 101 under development. As shown in FIG. 8, the powder molding apparatus 101 includes an upper mold 102, a floating lower mold 103, a side mold 104, and a lower lower mold 105, similar to the powder molding apparatus described in Patent Document 1. I have. When the upper mold 102 is lowered, the powder material P is pressurized. At this time, the pressure applied by the upper mold 102 is transmitted to the floating lower mold 103 through the powder material P, and a pressing force F101 which is a downward force is exerted.

  On the other hand, the floating lower mold 103 is applied with a floating load F102 which is a force upward from the floating load applying mechanism 106 such as an electric servo. During the molding of the powder material P, the control unit 111 controls the floating load applying mechanism 106 so that the floating load F102 is maintained at a predetermined set value. Further, a frictional force F103, which is an upward force, is exerted on the floating lower mold 103 by contact with the powder material P existing in the space on the side of the floating lower mold 103.

  When the pressure applied by the upper mold 102 is gradually increased after the molding process is started, the pressing force F101 exerted on the floating lower mold 103 also gradually increases. When the pressing force F101, which is a downward force, exceeds the sum of the floating load F102, which is an upward force, and the friction force F103, which is an upward force, the floating lower mold 103 starts to descend. When the lower end of the floating lower mold 103 comes into contact with the stopper 109, the lowering of the floating lower mold 103 stops, and the molding process ends. Thereby, a molded object is obtained.

  By the way, when the molding process is continuously performed in the powder molding apparatus 101, the mold temperature rises. Since the heat of the mold is conducted to the powder material P filled in the void surrounded by the mold, the powder material P filled with a higher temperature of the mold is filled with a lower temperature of the mold. The temperature is higher than that of the powder material P. When the temperature is high, the powder material P is more compressible (easily compressed) than when the temperature is low. When the compressibility of the powder material P is high, compared with the case where the compressibility of the powder material P is low, the powder material P that is above the floating lower mold 103 during the molding process until the same pressing force F101 is reached. Is further advanced, the timing at which the pressing force F1 reaches the same value is delayed. For this reason, the density of the powder material P existing in the space on the side of the floating lower mold 103 is increased. That is, in the state where the mold temperature is high, the density of the powder material P existing in the space on the side of the floating lower mold 103 becomes higher during the molding process than in the state where the mold temperature is low.

  When the density of the powder material P existing in the side space of the floating lower mold 103 is increased, the powder material P is more strongly pressed to the side of the floating lower mold 103, so that it exists in the side space of the floating lower mold 103. The frictional force F103 exerted on the floating lower mold 103 by the contact with the powder material P is increased. As the frictional force F103 increases, the upward force, which is the sum of the floating load F102 and the frictional force F103, increases even when the floating load F102, which is a downward force, is kept constant at a predetermined set value. The floating lower mold 103 is difficult to descend. That is, when the mold temperature is high, the floating lower mold 103 is less likely to descend than when the mold temperature is low. Therefore, the lowering speed of the floating lower mold 103 is lower than the lowering speed of the upper mold 102 during the molding process. The ratio becomes smaller. Further, when the ratio of the descending speed of the floating lower mold 103 to the descending speed of the upper mold 102 during the molding process is small, the change in the descending speed of the upper mold 102 with respect to the elapsed time from the start of the processing of the powder material is the same. If so, the time required from when the floating lower mold 103 starts to descend until it stops descending becomes longer.

  The inventors of the present invention have found that the quality of the molded product varies when the time required from when the floating lower mold 103 starts to descend to when it stops descending is intensively studied. That is, in order to suppress the variation in the quality of the molded body, it is necessary to reduce the variation in the time required from when the floating lower mold 103 starts to descend until it stops descending. However, in the case where the molding process is performed continuously, as described above, the mold temperature changes between the initial stage and the stage after the molding process is performed continuously, so that the floating lower mold 103 starts to descend. The ratio of the lowering speed of the lower floating mold 103 to the lowering speed of the upper mold 102 also changes from when the lowering is stopped. For this reason, there has been a problem that the quality of the molded product varies when the molding process is continuously performed.

  This invention is made | formed in view of the above background, and it aims at providing the powder shaping | molding apparatus which can suppress the dispersion | variation in the quality of a molded object also when performing a shaping | molding process continuously.

The present invention is a powder molding apparatus for compressing and molding a powder material filled in a space surrounded by a mold, the side mold having a first through hole surrounding a side of the powder material, and the first penetration An upper mold that is slidably fitted to the inner wall of the hole and pressurizes the powder material from above, and is arranged to be fitted to the inner wall of the first through hole at the lower part of the first through hole. A lower lower mold having two through holes, a floating lower mold that is slidably fitted to the inner wall of the second through hole, and applies a floating load to the powder material from below; and a floating load is applied to the floating lower mold A floating load applying mechanism to be applied, a temperature detection unit for directly or indirectly detecting the temperature of the powder material, and a floating load applied to the floating lower mold during the molding of the powder material are maintained at a set value. A control unit for controlling the floating load applying mechanism, and the control unit It is intended to lower the set value when the temperature of the powder material that has been detected by the temperature detector has risen to the reference temperature determined in advance.
The powder material becomes more compressible at higher temperatures. When the temperature of the mold rises by performing the molding process continuously, the temperature of the powder material also rises, so that the compressibility of the powder material increases. When the compressibility of the powder material is increased, the lowering timing of the floating lower mold is delayed, so that the density of the powder material existing in the side space of the floating lower mold is increased. When the density of the powder material existing in the side space of the floating lower mold becomes higher, the powder material is more strongly pressed to the side of the floating lower mold, so that the frictional force exerted on the side of the floating lower mold is increased and the floating material is floated. The lower mold 3 is difficult to descend. For this reason, the ratio of the lowering speed of the floating lower mold to the lowering speed of the upper mold during molding is reduced. When the ratio of the lowering speed of the floating lower mold to the lowering speed of the upper mold becomes smaller, the time required from the start of lowering of the floating lower mold to the stop of the lowering becomes longer with the same lowering speed of the upper mold. Canceling the delay in the lowering of the floating lower type by lowering the set value of the floating load when the temperature of the powder material detected directly or indirectly by the temperature detector rises to a predetermined reference temperature Can do. Therefore, it is possible to reduce the variation in the ratio of the lowering speed of the floating lower mold to the lowering speed of the upper lower mold from when the floating lower mold starts to descend until it stops descending. Thereby, it is possible to suppress variations in the quality of the molded body even when the molding process is continuously performed.

Furthermore, a plurality of different temperatures are defined as the reference temperature.
By setting multiple different temperatures as the reference temperature, cancellation of the increase in upward force exerted on the floating lower mold due to increased frictional force due to the increase in the temperature of the powder material can be performed with higher accuracy. Can do. Thereby, it is possible to further reduce the variation in the ratio of the lowering speed of the floating lower mold to the lowering speed of the upper lower mold from when the floating lower mold 3 starts to descend until it stops descending.

  According to the present invention, it is possible to suppress variations in the quality of a molded body even when molding is continuously performed.

It is a schematic diagram which shows schematic structure of the powder shaping | molding apparatus concerning this Embodiment. It is a schematic diagram explaining operation | movement of the powder shaping | molding apparatus concerning this Embodiment. It is a schematic diagram explaining operation | movement of the powder shaping | molding apparatus concerning this Embodiment. It is a schematic diagram explaining operation | movement of the powder shaping | molding apparatus concerning this Embodiment. It is a figure which shows an example of the setting value of the floating load with respect to the temperature of an upper mold | type. Floating load, upper mold position and floating lower mold position applied to the floating lower mold during the molding process for the filled powder material with respect to the elapsed time from the start of the molding process for the filled powder material It is a graph to show. It is a figure which shows another example of the setting value of the floating load with respect to the temperature of an upper mold | type. It is a figure which shows schematic structure of the powder shaping | molding apparatus in development.

Embodiment 1
Embodiment 1 of the present invention will be described below with reference to the drawings.
First, the schematic configuration of the powder molding apparatus 1 according to the present embodiment will be described with reference to FIG. The powder molding apparatus 1 compresses and molds a powder material P filled in a space surrounded by a mold. The powder material P is, for example, a powder obtained by mixing graphite, a lubricant, or the like with a metal powder such as iron, copper, nickel, chromium, tungsten, or molybdenum. FIG. 1 is a schematic diagram showing a schematic configuration of a powder molding apparatus 1 according to the present embodiment. As shown in FIG. 1, a powder molding apparatus 1 includes an upper die (upper punch) 2, a floating lower die (floating lower punch) 3, a side die (die) 4, and a lower lower die (fixed lower punch). 5, a floating load applying mechanism 6, a temperature detection unit 10, and a control unit 11.

  The side mold 4 has a first through hole 4a surrounding the side of the powder material P. The upper die 2 is slidably fitted to the inner wall 4aA of the first through hole 4a of the side die 4, and pressurizes the powder material P from above. The lower lower mold 5 is fixedly disposed so as to be fitted to the inner wall 4aA of the first through hole 4a at the lower part of the first through hole 4a, and has a second through hole 5a on the inner side. The floating lower mold 3 is slidably fitted to the inner wall 5aA of the second through hole 5a of the lower lower mold 5, and applies a floating load to the powder material P from below. The gap formed by the floating lower mold 3, the side mold 4 and the lower lower mold 5 is filled with the powder material P.

  The floating load applying mechanism 6 applies a floating load to the floating lower mold 3 through the rod 7. The floating load applying mechanism 6 is, for example, an electric servo, a hydraulic servo, an air cylinder, or the like. The temperature detection unit 10 directly or indirectly detects the temperature of the powder material P. As described above, since the powder material P is filled in the space surrounded by the mold, the powder material P is thermally conducted from the mold to the powder material P. For this reason, the temperature of the powder material P can be replaced by the temperature of the mold. That is, the temperature of the powder material P can be indirectly detected by detecting the temperature of the mold (for example, the upper mold 2). In this Embodiment, the temperature of the powder material P is indirectly detected by measuring the temperature of the outer peripheral surface 2a of the upper mold | type 2 with the infrared sensor as the temperature detection part 10. FIG.

  The control unit 11 controls the floating load application mechanism 6 so that the floating load applied to the floating lower mold 3 is kept constant at a predetermined set value during the molding of the powder material P. A floating load applied to the floating lower mold 3 is detected by a load sensor 8 installed between the rod 7 and the floating load applying mechanism 6. The load sensor 8 is a load converter such as a load cell, for example. A value detected by the load sensor 8 is input to the control unit 11. Based on this detection value, the control unit 11 controls the floating load applying mechanism 6 so that the floating load is maintained at the set value.

Next, operation | movement of the powder shaping | molding apparatus 1 concerning this Embodiment is demonstrated with reference to FIGS. 2 to 4 are schematic diagrams for explaining the operation of the powder molding apparatus 1.
As shown in FIG. 2, after filling the gap formed by the floating lower mold 3, the side mold 4 and the lower lower mold 5 with the powder material P, the upper mold 2 is lowered to add the powder material P. Start pressure.

  As shown in FIG. 3, when the upper mold 2 pressurizes the powder material P, the pressure applied by the upper mold 2 is transmitted to the floating lower mold 3 through the powder material P, and the pressing force F1 is a downward force. Is affected. On the other hand, a floating load F2 that is an upward force from the floating load applying mechanism 6 is applied to the floating lower mold 3. During the molding process, the control unit 11 controls the floating load applying mechanism 6 so that the floating load F2 is maintained constant at a predetermined set value. Furthermore, a frictional force F3, which is an upward force, is exerted on the floating lower die 3 by contact with the powder material P existing in the space on the side of the floating lower die 3. When the pressurization by the upper mold 2 is gradually increased after the molding process is started, the pressing force F1 exerted on the floating lower mold 3 by the upper mold 2 through the powder material P also gradually increases. When the pressing force F1 that is a downward force exceeds the sum of the floating load F2 that is an upward force and the friction force F3 that is an upward force, the floating lower die 3 starts to descend.

  As shown in FIG. 4, when the lower end of the floating lower die 3 comes into contact with the stopper 9, the lowering of the floating lower die 3 stops and the molding process is completed. Thereby, the molded object W is obtained.

  By the way, in the powder molding apparatus 1, when the molding process is continuously performed, the temperature of the mold (upper mold 2, floating lower mold 3, side mold 4, and lower lower mold 5) rises. Since the heat of the mold is conducted to the powder material P filled in the void surrounded by the mold, the powder material P filled with a higher temperature of the mold is filled with a lower temperature of the mold. The temperature is higher than that of the powder material P.

  When the density of the powder material P existing in the space S2 on the side of the floating lower mold 3 is increased, the powder material P is more strongly pressed against the side of the floating lower mold 3, so that the powder material P is pressed into the space on the side of the floating lower mold 3. The frictional force F3 exerted on the floating lower mold 3 by the existing powder material P increases. As described above, when the pressing force F1, which is a downward force, exceeds the sum of the floating load F2, which is an upward force, and the friction force F3, which is an upward force, the floating lower die 3 is lowered. Even if the floating load F2 is kept constant at the set value, if the compressibility is improved, the timing at which the pressing force F1 reaches the applied pressure of the upper mold 2 is delayed. The density of the powder material P existing in S2 is increased. That is, in the state where the mold temperature is high, the density of the powder material P existing in the space S2 on the side of the floating lower mold 3 is increased during the molding process and the frictional force F3 is higher than in the state where the mold temperature is low. growing.

  When the frictional force F3 is increased, the upward force that is the sum of the floating load F2 and the frictional force F3 is increased, so that the floating lower die 3 is difficult to descend. If it becomes difficult for the floating lower mold 3 to descend, the time required for the floating lower mold 3 to start descending after the floating lower mold 3 begins to descend becomes longer.

  The inventors of the present invention have found that the time required for the floating lower die 3 from starting to descend until it stops descending during the molding process affects the quality variation of the molded body. In other words, in order to suppress the variation in the quality of the molded body, the variation in the ratio of the descending speed of the floating lower mold 3 to the descending speed of the upper mold 2 from when the floating lower mold 3 starts to descend until it stops descending is changed. There is a need to reduce.

  In the powder molding apparatus 1 according to the present embodiment shown in FIG. 1, the control unit 11 detects the floating load when the temperature of the powder material P detected by the temperature detection unit 10 rises to a predetermined reference temperature. Decrease the setting value. Since the temperature of the powder material P is replaced with the temperature of the upper mold 2 as described above, the control unit 11 determines that the temperature of the upper mold 2 detected by the temperature detection unit 10 is a predetermined reference temperature. Decrease the floating load setting when rising.

  FIG. 5 is a diagram illustrating an example of a set value of the floating load with respect to the temperature of the upper mold 2. As shown in FIG. 5, when the temperature of the upper mold 2 is 20 ° C. or more and less than 40 ° C., the set value of the floating load is 300 kN, and when the temperature of the upper mold 2 is 40 ° C. or more and less than 60 ° C. Set the value to 250 kN. That is, in the example shown in FIG. 5, the reference temperature for changing the set value of the floating load is 40 ° C. When the temperature of the upper mold 2 rises above the reference temperature of 40 ° C., the set value of the floating load is lowered from 300 kN to 250 kN.

  As described above, when the mold temperature rises by continuously performing the molding process, the timing at which the pressing force F1 reaches the same value is delayed compared to before the mold temperature rises. Since the frictional force F3 exerted on is increased, the floating lower mold 3 is difficult to descend. For this reason, the ratio of the descending speed of the floating lower mold 3 to the descending speed of the upper mold 2 from when the floating lower mold 3 starts to descend until it stops descending during molding is reduced. By lowering the set value of the floating load when the temperature of the powder material P rises due to the rise in the mold temperature, the delay in the lowering timing of the floating lower mold 3 can be cancelled. Therefore, it is possible to reduce the variation in the ratio of the lowering speed of the floating lower mold to the lowering speed of the upper lower mold from when the floating lower mold 3 starts to descend until it stops descending. Thereby, it is possible to suppress variations in the quality of the molded body even when the molding process is continuously performed.

  When the temperature of the upper mold 2 is lower than the lower limit temperature (20 ° C. in the example shown in FIG. 5), the molding process is not performed, and the molding process is performed after the upper mold 2 is warmed so that the upper mold temperature becomes equal to or higher than the lower limit temperature. May be started. Further, when the temperature of the upper mold 2 is equal to or higher than the upper limit temperature (60 ° C. in the example shown in FIG. 5), the molding process may be stopped.

  FIG. 6 shows the floating load exerted on the floating lower mold 3 during the molding process for the filled powder material P with respect to the elapsed time from the start of the molding process for the filled powder material P. It is a graph shown about a position and a position of floating lower type 3. Here, the solid line L1 represents the position of the lower end of the upper mold 2 and the solid line L2 represents the position of the upper end of the floating lower mold 3. The solid line L3 indicates the floating load exerted on the floating lower mold 3 when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. The solid line L4 indicates the case where the temperature of the upper mold 2 is 40 ° C. or higher and lower than 60 ° C. Represents the floating load exerted on the floating lower mold 3 at. The horizontal axis represents the elapsed time (sec) from the start of the molding process on the filled powder material P. The vertical axis for the solid lines L1 and L2 (left vertical axis in the figure) represents the position (mm) relative to the upper end of the lower lower mold 5, and the vertical axis for the solid lines L3 and L4 (right side in the figure) The vertical axis represents the floating load (kN).

  As shown in FIG. 6, the position of the lower end of the upper mold 2 (solid line L1) and the position of the upper end of the floating lower mold 3 (solid line L2) gradually decrease from the start time t1 of the forming process. The floating load exerted on the floating lower die 3 is controlled so as to gradually increase from the starting time t1 of the forming process and to be kept constant at the set value when it rises to the set value of the floating load. When the temperature of the upper mold 2 indicated by the solid line L3 is 20 ° C. or higher and lower than 40 ° C., the floating load exerted on the floating lower mold 3 reaches the set value at the time t3, and then remains constant at the set value 300 kN from there. To be controlled. On the other hand, when the temperature of the upper mold 2 indicated by the solid line L4 is not lower than 40 ° C. and lower than 60 ° C., the floating load exerted on the floating lower mold 3 reaches the set value at the time point t2, and is constant at the set value 250 kN therefrom. It is controlled to be maintained.

  The change in the position of the lower end of the upper mold 2 during the molding process is the same in the solid line L1 when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C. That is, when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C., the lowering speed of the upper mold 2 with respect to the elapsed time since the processing of the powder material is started. The change is the same. The change in the position of the upper end of the floating lower mold 3 is the same as the solid line L2 when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C. That is, when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C., the lowering speed of the floating lower mold 3 with respect to the elapsed time from the start of processing of the powder material The changes are the same. Therefore, when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C., the upper mold 2 from when the floating lower mold 3 starts to descend until it stops descending. The ratio of the lowering speed of the floating lower mold 3 to the lowering speed is the same. As described above, even if the temperature of the upper mold 2 rises, the set value of the floating load is reduced, so that the lower mold 3 can respond to the lowering speed of the upper mold 2 after the floating lower mold 3 starts to descend. Variations in the ratio of the descending speed of the floating lower mold 3 can be reduced.

  At the time point t4, the position of the lower end of the upper mold 2 indicated by the solid line L1 and the position of the upper end of the floating lower mold 3 indicated by the solid line L2 are no longer lowered. That is, time t4 indicates the time when the forming process is completed. When the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C., the period during which the molding process is performed is the period M3. That is, when the temperature of the upper die 2 is 20 ° C. or higher and lower than 40 ° C. or 40 ° C. or higher and lower than 60 ° C., the time required for the floating lower die 3 to start moving down and to stop moving down is The same.

  When the temperature of the upper mold 2 is 20 ° C. or higher and lower than 40 ° C., the period during which the floating load applied to the floating lower mold 3 is controlled to be maintained at the set value is the period M1. When the temperature of the upper mold 2 is not lower than 40 ° C. and lower than 60 ° C., the period during which the floating load applied to the floating lower mold 3 is controlled to be maintained at the set value is the period M2. That is, when the set value of the floating load is reduced, the period during which the floating load applied to the floating lower mold 3 is controlled to be maintained at the set value becomes longer.

[Modification 1]
In the example shown in FIG. 5, one temperature is defined as the reference temperature, but a plurality of different temperatures may be defined as the reference temperature. FIG. 7 is a diagram illustrating another example of the set value of the floating load with respect to the temperature of the upper mold 2. For example, as shown in FIG. 7, when the temperature of the upper mold 2 is 20 ° C. or higher and lower than 30 ° C., the setting value of the floating load is 300 kN, and when the temperature of the upper mold 2 is 30 ° C. or higher and lower than 40 ° C. Is set to 275 kN. When the temperature of the upper mold 2 is 40 ° C. or more and less than 50 ° C., the setting value of the floating load is 250 kN, and when the temperature of the upper mold 2 is 50 ° C. or more and less than 60 ° C., the setting value of the floating load is 225 kN. That is, in the example shown in FIG. 7, three different temperatures, 30 ° C., 40 ° C., and 50 ° C., are defined as reference temperatures for changing the set value of the floating load. As described above, since a plurality of different temperatures are determined as the reference temperature, the lowering timing of the lowering of the floating lower mold due to the increase in compressibility due to the increase in the temperature of the powder material accompanying the increase in the mold temperature. The delay can be canceled more accurately. Thereby, the dispersion | variation in the time required from the floating lower mold | type 3 starting a descent to stopping a descent | fall can be reduced more.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. In the above embodiment, an infrared sensor that is a non-contact type temperature sensor that measures the temperature of the outer peripheral surface of the upper mold is used as the temperature detection unit, but the present invention is not limited to this. As the temperature detection unit, for example, a contact-type temperature sensor such as a thermocouple provided on the outer peripheral surface or inside of the upper mold may be used. In the above embodiment, the temperature of the powder material P is replaced with the upper mold temperature, but the present invention is not limited to this. The temperature of the powder material P may be replaced with any one of the floating lower mold, the side mold, and the lower lower mold. Further, for example, as a temperature detection unit, a temperature sensor of a contact type such as a thermocouple provided on a surface in contact with the powder material P in a mold (for example, an upper mold) is used, and the temperature of the powder material P is directly measured. Also good. In the above embodiment, the lower lower mold is fixedly arranged so as to be fitted to the inner wall of the first through hole in the lower part of the lateral mold, but it is not necessarily required to be arranged fixedly. For example, the lower lower mold may be arranged to be slidably fitted to the inner wall of the first through hole in the lower part of the lateral mold and apply a floating load to the powder material from below. The upper mold and the lower mold may be divided into a plurality of parts.

DESCRIPTION OF SYMBOLS 1 Powder shaping | molding apparatus 2 Upper type | mold 3 Floating lower type | mold 4 Side type | mold 4a 1st through hole 5 Lower lower type | mold 5a 2nd through hole 6 Floating load provision mechanism 7 Rod 8 Load sensor 10 Temperature detection part 11 Control part P Powder material

Claims (2)

A powder molding apparatus for compressing and molding a powder material filled in a void surrounded by a mold,
A lateral mold having a first through hole surrounding the lateral side of the powder material;
An upper mold that slidably fits with the inner wall of the first through hole and pressurizes the powder material from above;
A lower lower mold that is arranged to fit with an inner wall of the first through hole at a lower portion of the first through hole, and has a second through hole on the inside;
A floating lower mold that slidably fits with the inner wall of the second through hole and applies a floating load to the powder material from below;
A floating load applying mechanism for applying a floating load to the floating lower mold;
A temperature detector for directly or indirectly detecting the temperature of the powder material;
A control unit that controls the floating load application mechanism so that the floating load applied to the floating lower mold is maintained at a set value during the molding of the powder material,
The powder molding apparatus, wherein the control unit decreases the set value when the temperature of the powder material detected by the temperature detection unit rises to a predetermined reference temperature.   The powder molding apparatus according to claim 1, wherein a plurality of different temperatures are set as the reference temperature.

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