KR20130117677A - Method for producting powder molding products, and powder molding apparatus - Google Patents

Abstract

The powder molding apparatus 1 of the present invention includes a die 11, a lower punch 21, an upper punch 31, an upper punch driving unit 72 for advancing and retreating the upper punch 31, and an upper punch. The plurality of pressurizing DDV servo drive devices 75 connected to the 31 and the pressure connecting part 76, and the image punch drive unit 72 advances the image punch 31, and then the plurality of pressure applications The material powder P in the charging section A is pressurized by the DDV type servo drive device 75, and the force in the direction opposite to the pressing force of the pressurized DDV type servo drive device 75 is changed before the transfer to the pressing step. The image is generated by the upper punch drive unit 72.

Description

Manufacturing method and powder molding apparatus of powder molded article {METHOD FOR PRODUCTING POWDER MOLDING PRODUCTS, AND POWDER MOLDING APPARATUS}

This invention relates to the manufacturing method of a powder molded article, and a powder molding apparatus.

As is well known, in the fields of automobile parts, electronic parts, cutting tools and the like, ceramic powders including metal powders and alumina are molded into powder molded articles, and the powder molded articles are sintered to produce products made of powder sintered articles. Powder metallurgy sintering is widely used.

According to the powder metallurgy sintering method, a powder forming apparatus having a die, a lower punch for forming a filling portion together with a die, and an upper punch supported to be able to move forward and backward toward the filling portion, wherein the filling powder formed in the die is filled with a material powder. The powder is pressed by the upper punch and the lower punch to form a powder molded article. And a powder sintered article is manufactured by sintering this powder molded article on predetermined conditions.

The said powder molded article shrink | contracts significantly at the time of sintering, and the magnitude | size of the shrinkage is largely influenced by the density of a powder molded article. Therefore, it is preferable to suppress the shrinkage at the time of sintering by making the deflection of the density distribution of the powdered molded article shape | molded by rolling powder small.

Therefore, in order to reduce the deflection of the density distribution of the powder molded article, a die fixing method of fixing the die to lower the upper punch, raising the lower punch, and compacting the powder of the material in the filling part from both the upper and lower sides (for example, a patent document) 1) or the withdrawal method in which the die is lowered at a speed of about 1/2 of the upper punch when the lower punch is fixed, thereby compacting and molding the material powder in the live part from the lower side (for example, For example, see patent document 2). However, if the supply amount of the material powder is deflected along the site of the filling part during filling of the material powder, it is difficult to avoid the occurrence of the deflection of the density distribution of the powder molded article.

Moreover, in order to reduce the deflection of the density distribution of a powder molded article and to improve the precision of a powder sintered article, the technique which adjusts the compression amount of a material powder by controlling the up-down position of an upper punch with a DDV-type servo drive device is developed. (For example, refer patent document 3).

Japanese Patent Laid-Open No. 1-181997 Japanese Patent Laid-Open No. 5-92299 Japanese Unexamined Patent Publication No. 2010-234377

However, in the case of powder-molding a molded article at high speed and high output, in the case of using a powder molding apparatus in which an image punch drive unit and a pressurized DDV-type servo drive apparatus are arranged on an image platen, the shape of the powder molded article or the like does not matter. Without this, there is a technical request to further reduce the deflection of the density distribution of the powder molded article. Here, the image punch drive unit serves to move the image punch at high speed, and the pressure DDV type servo drive device plays a role of pressing the material powder which has moved at high speed to reach the charging section at high power.

In addition, when the pressure DDV type servo drive device is used exclusively for the pressure side (the side for pressing the material powder), when the high-speed shifted phase punch is transferred to the pressure step, it is applied to the rods of the pressure DDV type servo drive devices. Differences in the amount of advancement may occur and incline may occur in the upper punch plate. In this case, when the image punch plate is inclined and shifted to the pressing step, it may not be possible to adjust a sufficient amount of compression of the material powder by the pressurizing DDV servo drive device.

This invention advances an image punch with respect to die | dye by an image punch drive part, and pressurizes DDV in a pressurization process in the case of adjusting and pressurizing the compression amount of a material powder with a pressure DDV type servo drive device. Provided are a method for producing a powder molded article and a powder molding apparatus capable of adjusting a stable compression amount of a powder molded article by a mold servo drive device and further reducing the deflection of the density distribution of the powder molded article.

A powder molding apparatus according to an aspect of the present invention includes a die on which a filling portion filled with a material powder is formed, a lower punch mounted on the die so as to be movable relative to the die, and forming a filling portion together with the die, and above the die. An image puncher disposed to be able to advance and retract with respect to the charging unit, an image punch driver connected to the image punch and a connecting portion to advance and retreat the image punch, an image platen on which the image punch driver is formed, and the image platen A plurality of pressurizing DDV-type servo driving devices formed in the connecting portion and connected to the image punch through the pressure connection portion disposed at intervals from the connection portion, and the image punch driving portion advances the image punch, A powder molding apparatus comprising a control unit for pressurizing a material powder in the charging unit by a DDV servo drive device , And the upper punch unit is configured to, at least one of the plurality of the pressure connection, generating the pushing force and the force in the opposite direction of the pressure DDV-type servo driving apparatus prior to the start of the pressing of the material powder in the charging section.

A method for producing a powder molded article according to another aspect of the present invention includes a die having a filling portion filled with a powder of material, a lower punch mounted relative to the die to form a filling portion with the die, and an upper portion of the die. An image punch disposed to be able to move forward and backward with respect to the charging portion, an image punch drive portion connected to the image punch and a connecting portion to advance and retract the image punch, an image platen on which the image punch drive portion is formed, and the image A plurality of pressurizing DDV-type servo drives formed on the platen and connected through pressure connecting portions arranged at intervals from the image punching portion and the connecting portion, wherein the image punch driving portion advances the image punches, To a powder molding apparatus configured to pressurize a material powder in the filling section by the plurality of pressurizing DDV servo drives. A method for producing a powder molded article, wherein a force in a direction opposite to the pressing force of the pressurizing DDV servo drive device is applied to at least one of the plurality of pressurizing connections before the phase punch starts pressurizing the material powder in the filling part. Generate.

According to the powder molding method and the powder molding apparatus, the force in the direction opposite to the pressing force is applied to at least one of the plurality of pressure connecting portions connecting the image punch and the pressurizing DDV servo drive device before the image punch pressurizes the material powder in the filling portion. The force in the rearward direction acts on the pressure DDV type servo drive device having a large amount of advancement of the load in each pressure DDV type servo drive device (for example, through the upper punch plate). As a result, the inclination of the upper punch becomes smaller (for example, horizontally) in the charging section, and the deflection of the load advance amount of each pressurized DDV servo drive device is reduced.

As a result, the inclination of the image punch with respect to the charging part becomes small, and it becomes possible to stably adjust the compression amount of the material powder by the DDV type servo drive device for pressurization after the pressurization process transition. Thereby, by making deflection of a density distribution small, the precision of the powder sintered article at the time of sintering a powder molded article and making it a powder sintered article can be improved.

Here, decreasing the inclination of the image punch with respect to a charging part means that the bias of the load advance amount of the DDV type servo drive device for pressurization is small when pressurizing the material powder charged to the charging part, and each DDV type servo drive device for pressurization is small. This means adjusting the inclination of the image punch in the direction in which the compression amount of the material powder can be adjusted by advancing the rod, and means, for example, the case where the axis of the image punch corresponds to the axis of the charging section.

A DDV type servo drive may be sufficient as the said image punch drive part, and the said control part may output to the image punch drive part the signal which positions the said connection part to the back direction of a forward direction rather than the said pressure connection part.

In this case, the DDV type servo drive device as the upper punch drive part makes the connection part correspond to the position of the rear side in the forward direction than the pressure connection part, so that the force in the opposite direction to the pressing force of the pressure DDV type servo drive device is stably generated in the connection part. You can.

A ball screw drive device may be sufficient as the said image punch drive part, and the said control part may output the signal which positions the said connection part to the back direction of a forward direction rather than the said pressure connection part, to the said image punch drive part.

In this case, the ball screw drive device as the upper punch drive part makes the connection part correspond to the position of the rear side in the forward direction than the pressure connection part, so that the force in the direction opposite to the pressing force of the pressure DDV servo drive device can be stably generated in the connection part. Can be.

The said upper punch drive part may be a hydraulic cylinder, The back pressure adjusting means which adjusts the back pressure accompanying advancing of the said upper punch is formed in the said hydraulic cylinder, The said control part is the said pressurization part in at least one of the said press connection parts. You may output the signal which generate | occur | produces the force in the direction opposite to the pressing force of a DDV-type servo drive apparatus by the said back pressure.

In this case, by adjusting the back pressure in the case of advancing the rod of the hydraulic cylinder as the upper punch drive unit, the force in the direction opposite to the pressing force of the pressurized DDV servo drive unit can be stably generated.

According to the powder molding method and the powder molding apparatus according to the present invention, before the image punch pressurizes the material powder in the filling portion, at least one of the plurality of pressure connecting portions connecting with the image punch and the DDV type servo drive device for pressurization is opposite to the pressing force. Since the force in the direction is generated, the inclination of the image punch with respect to the charging portion becomes small. Therefore, the compression amount adjustment of the material powder by the pressurizing DDV type servo drive apparatus after shifting to a pressurization process can be performed stably, As a result, the deflection of a density distribution can be made stable stably.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the outline of the powder molding apparatus which concerns on one Embodiment of this invention.
FIG. 2 is a diagram showing an example of arrangement of the phase punch movement DDV servo drive device and the pressurized DDV servo drive device according to one embodiment. FIG.
3 is a diagram illustrating an example of a configuration of a DDV servo drive device for image punch movement according to one embodiment.
4 is a diagram illustrating an example of a circuit configuration of a phase punch movement DDV servo drive device and a pressurized DDV servo drive device according to one embodiment.
5 is a diagram illustrating an example of a configuration of a pressurized DDV servo drive device according to an embodiment.
6 is a diagram illustrating an example of a control unit according to an embodiment.
7 is a diagram illustrating an example of a schematic configuration of a database according to an embodiment.
8 is a block diagram illustrating an outline of an operation of a powder molding apparatus according to one embodiment.
9 is a block diagram showing an outline of the action of the powder molding apparatus according to the embodiment.
It is a figure explaining the operation | movement of the powder molding apparatus which concerns on one Embodiment, and is a figure which shows the operation | movement of the image punch in a powder molding cycle.
FIG. 10B is a view for explaining the operation of the powder molding apparatus according to the embodiment, and the image punch, the image punch DDV servo drive device and the pressure DDV servo drive device in the portion enclosed by the circle K in FIG. 10A. It is a figure which shows the detail of the operation | movement of.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings.

FIG. 1: is a figure which shows the powder molding apparatus 1 of this embodiment. The powder molding apparatus 1 is provided with the die set (mold) 10 and the powder molding press 50, For example, in the die which obliquely filled and fixed the metal powder (material powder) P, The upper punch and the lower punch are powder-formed by the die-fixing method in which forward and backward punches.

The die set 10 includes a die 11 having a through hole formed in the center, a lower punch 21 disposed below the die 11, and an upper punch 31 disposed above the die. When the lower punch 21 is inserted into the through hole of 11, the filling part A is formed, and the filling part A is filled with the metal powder P. As shown in FIG.

The die 11 is disposed in the center portion of the die plate 12, and the guide plate 18H is formed in the die plate 12.

The lower punch 21 protrudes from the lower punch plate 13 which is relatively movable with the base plate 14 fixed on the main body bed 68. The lower punch plate 13 is connected to the pushing plate 44 through the lower punch DDV servo drive device 22. As the guide rod 40 extending downward from the lower punch plate 13 is inserted into the guide hole of the pushing plate 44, the lower punch plate 13 shifts in the horizontal direction with respect to the pushing plate 44. While this is suppressed, it is possible to move relative to the vertical direction.

In addition, the pushing plate 44 is connected to the T-shaped joint 45, and the T-groove 45A of the T-shaped joint 45 is connected to the T-shaped portion of the lower ram 61. As a result, the lower ram 61 advances and retreats in the vertical direction, so that the lower punch 21 and the lower punch plate 13 can move in the vertical direction together with the lifting plate 44.

In addition, the guide rod 41 which protrudes below the die plate 12 is inserted into the guide hole of the base plate 14. Thereby, the die plate 12 is able to move relative to the base plate 14 in the vertical direction.

In addition, the lower punch 21 is movable relative to the lifting plate 44 in the vertical direction as the lower punch DDV servo drive device 22 moves forward and backward by the position control function. Thereby, the relative position of the lower punch 21 in the up-down direction with respect to the lower ram 61 is adjustable.

The upper punch 31 is fixed to the upper punch plate 34, is formed to protrude downward from the upper punch plate 34 toward the die 11, and can be inserted into the filling part A. have.

The upper punch plate 34 is formed while the guide rod 18 protrudes, and the guide rod 18 is slidably inserted with respect to the guide hole 18H formed in the die plate 12. Thereby, when the upper punch 31 moves to the up-down direction with respect to the die 11, it suppresses that the upper punch 31 shifts with respect to the die 11. As shown in FIG. Moreover, the upper punch plate 34 is connected with the T type joint of the DDV type servo drive device 72 for image punch which comprises the powder molding press 50, and the DDV type servo drive device 75 for pressurization, It moves up and down.

The powder molding press 50 includes a press lower main body 60, a press upper main body 70, a control unit 80, a shoe box 90, and a laser shape measuring instrument (not shown). Based on the thickness of the powder molded article W measured by the laser shape measuring device, the vertical direction position of the image punch 31 is adjusted, and the compression amount of the metal powder P by the image punch 31 is adjusted.

The lower press main body 60 has a lower ram 61, a lower ram driver 62, a main body support 63, a lower ram drive part support plate 64, a lower ram base plate 65, and a rotation stop. The rod 66, the lower ram guide plate 67, and the main body bed 68 are provided. The main body support part 63, the lower ram drive part support plate 64, the lower ram base plate 65, the lower ram guide plate 67, and the main body bed 68 are arranged in this order from below. The rotation stop rod 66 is formed so that it may extend in the up-down direction between the lower ram base plate 65 and the lower ram guide plate 67.

Moreover, the press lower main body part 60 and the press upper main body part 70 are connected by the connecting member 52. As shown in FIG.

The lower ram drive part 62 includes a lower ram drive motor 62M formed on the lower ram drive part support plate 64, a drive pulley 62A formed on a rotation shaft of the lower ram drive motor 62M, a transmission belt 62B, And 62C of driven pulleys and 62D of concentric rams with 62C of driven pulleys. According to the lower ram drive part 62, since the transmission belt 62B is wound around the driving pulley 62A and the driven pulley 62C, the rotation of the lower ram drive motor 62M is transmitted to the driven pulley 62C, The ram drive shaft 62D is rotated.

Moreover, the male screw 62E formed in the front end side of the lower ram drive shaft 62D is screwed with the female screw 61A which extends along the axis line from the center of the lower end surface of the lower ram 61, and the lower ram drive shaft 62D. By this rotation, the lower ram 61 rises and falls.

The lower ram 61 is provided with a female screw 61A that can engage with the male screw 62E on the lower side of the lower ram 61. The lower ram 61 is inserted into the guide member 67A formed on the lower ram guide plate 67, and the lower ram 61 is slidable in the vertical direction. The lower ram 61 is fixed to the lower ram base plate 65 while the base end (lower side) is extended upward from the lower ram base plate 65.

65 A of through-holes are formed in the center part of the lower ram base plate 65, 61 A of female threads of the lower ram 61 are concentric with 65 A of through-holes. The har ram drive shaft 62D is inserted into the female screw 61A of the lower ram 61, and the male screw 62E and the female screw 61A are screwed together.

Moreover, when the lower ram drive shaft of the lower ram drive motor 62M rotates by rotating the rotation stop rod 66 through the hole 65B formed in the lower ram base plate 65, the lower ram 61 and lower The ram base plate 65 is prevented from rotating.

As a result, when the lower ram drive shaft of the lower ram drive motor 62M is rotated, the male screw 62E of the lower ram drive shaft 62D and the female screw 61A of the lower ram 61 are screwed together, thereby lowering the lower ram drive motor. The rotation of 62M is converted to the movement of the up-down direction, and the lower ram 61 advances and moves in the up-down direction.

The press upper main body 70 includes an image platen 71, an image punch DDV servo drive device (image punch drive unit) 72, and a pressure DDV servo drive device 75. In this embodiment, as shown in FIG. 2, for example, the DDV type servo drive device 72 for punching is formed in the center of the upper surface of the image platen 71, and the DDV type servo drive device for pressure ( For example, 75 sets two sets as one set, and each pair is arrange | positioned between the DDV-type servo drive device 72 and the charging part A for phase punches, and two sets of DDV type servo drives for pressurization are provided. The devices 75 are arranged perpendicular to each other. In addition, the dashed-dotted line has shown the upper punch 31, the die 11, and the filling part A. FIG.

By this structure, the up-down direction position of the upper punch 31 in the axial direction of the upper punch 31, and the inclination of the front end surface of the upper punch 31 are opposed to each other in the radial direction (between the filling portions A). Relative position of the site) can be adjusted.

The DDV type servo drive device 72 for image punching has a recess formed in the circumferential direction at the tip of the rod, and the recess formed on the convex portion 34A formed at the center of the image punch plate 34 ( 34B). Thereby, the connection part 73 of the image punch DDV servo drive 72 and the image punch 31 is comprised.

In addition, the rod DDV servo drive device 72 for the upper punch moves the upper punch plate 34 and the upper punch 31 in the vertical direction when the rod moves forward and backward.

The pressurized DDV servo drive device 75 is swingably connected through the upper punch plate 34 and the pressure connecting portion 76, and the rod is moved through the upper punch plate 34 through the upper punch plate 34 as the rod moves forward. The metal powder P in the filling part A is pressurized by this. Moreover, when the DDV type servo drive apparatus 75 for pressurization moves the upper punch 31 up and down by the DDV type servo drive apparatus 72 for up punching, the rod advances and retreats in an up-down direction.

In this embodiment, the DDV type servo drive device 72 for image punching has a schematic structure as shown in FIG. 3, for example. Moreover, the DDV type servo drive apparatus 22 for lower punches for advancing and lowering the lower punch 21 also has the same structure.

Hereinafter, with reference to FIG. 3, the bidirectional propulsion type DDV (Direct Drive Volume Control) servo drive device which comprises the DDV type servo drive device 72 for image punching is demonstrated.

The DDV servo drive device 72 for phase punching includes an adder 72F, a servo amplifier 72G, a servo motor 72M, a hydraulic pump 72P, a hydraulic cylinder 72C, and a position detection sensor. 72D is provided. The position detection sensor 72D detects the amount of advance and fall of the rod of the hydraulic cylinder 72C.

The adder 72F adds the control signal Sd related to the position control or the pressure control inputted from the outside and the feedback signal St from the position detection sensor 72D to output to the servo amplifier 72G. The servo amplifier 72G amplifies the signal from the adder 72F to drive the servo motor 72M.

The servo motor 72M drives hydraulic oil 72P to drive hydraulic oil to the hydraulic cylinder 72C, and advances or retracts the rod of the hydraulic cylinder 72C to adjust its amount of retraction.

In addition, as shown in FIG. 4, in the DDV servo drive device 72 for the upper punch, the hydraulic pump 72P, the hydraulic oil storage unit 72S, and the hydraulic oil tank 72T are parallel to the hydraulic cylinder 72C. It is connected to and it is possible to adjust the difference of the hydraulic fluid of 72C of hydraulic cylinders.

Moreover, when the hydraulic cylinder 72C advances, the fall prevention valve 72V is formed in the side which hydraulic oil returns, and the drop prevention valve 72V is opened, and a rod advances and a drop prevention valve 72V is provided. ) Is closed, and the forward of the rod stops.

As a result, a control signal is output to the DDV type servo drive device 72 for image punching, and the advance / retraction amount of the rod of the hydraulic cylinder 72C changes, so that the DDV type servo drive device for image punches 72 can be controlled in position. It is.

Moreover, pressure sensors 72A and 72B are connected to the rod side and the head side of the hydraulic cylinder 72C, respectively, and the pressure of the hydraulic fluid of the rod side and the head side is detectable.

It goes without saying that the other well-known DDV servo drive apparatus other than the above is applicable.

Moreover, the DDV type servo drive apparatus 75 for pressurization has a schematic structure as shown in FIG. 5, and in the pressurizing process, the phase punch 31 can pressurize the metal powder P in the filling part A. At the time, the deflection of the amount of advancement in each position of the upper punch 31 is adjusted.

The pressurized DDV type servo drive device 75 includes an adder 75F, a servo amplifier 75G, a servo motor 75M, a pressure side exclusive hydraulic pump 75P, a hydraulic cylinder 75C, and a position detection. The sensor 75D is provided. The position detection sensor 75D detects the amount of advancement of the rod of the hydraulic cylinder 75C.

The adder 75F, the servo amplifier 75G, and the position detection sensor 75D have the same function as the case of the DDV type servo drive device 72 for image punching. The servomotor 75M drives the hydraulic oil pressurized by driving the hydraulic pump 75P to the hydraulic cylinder 75C, and adjusts the amount of load advance of the hydraulic cylinder 75C.

Moreover, as shown in FIG. 4, the pressurized DDV-type servo drive device 75 has a hydraulic pump 75P, a hydraulic oil storage part 75S, a hydraulic oil tank 75T, and a prefill, with respect to the hydraulic cylinder 75C. The valve 75V is connected in parallel, and it is possible to adjust the difference of the hydraulic oil of the hydraulic cylinder 75C.

The prefill valve 75V is capable of opening and closing control by the pilot pressure of the hydraulic oil supplied from the pilot pump 78. At the time of the rod forward of the hydraulic cylinder 75C, the prefill valve 75V is "opened" by the pilot pressure, and a large amount of oil can be sucked from the hydraulic oil tank 75T to the hydraulic cylinder 75C, thereby pressurizing it. The load of the DDV type servo drive device 75 advances at high speed. Moreover, the prefill valve 75V respond | corresponds the backflow of the hydraulic oil from the hydraulic cylinder 75C to the hydraulic oil tank T, and respond | corresponds to the pressurization process of the load of the DDV type servo drive apparatus 75 for pressurization. In addition, the prefill valve 75V acts as a check valve at the time of the rod retraction of the pressure-type DDV servo drive apparatus 75. In this way, the prefill valve 75V appropriately controls the high speed forward, the pressurizing step, and the retraction of the rod of the pressurized DDV servo drive device 75.

Moreover, the pressure sensor 75A is connected to the rod side of the hydraulic cylinder 75C, and the pressure of hydraulic fluid is detectable.

As a result, the pressure sensor 75A outputs a control signal to the pressure DDV servo drive device 75 to adjust the amount of advancement of the rod of the hydraulic cylinder 75C, whereby the pressing force of the pressure DDV servo drive device 75 is adjusted. Control and position control are carried out.

It goes without saying that the other well-known DDV servo drive apparatus other than the above is applicable.

The shoe box 90 moves forward and backward on the die plate 12 toward the charging unit A by the signal output from the control unit 80 with respect to the drive source, and the upper punch 31 and the lower punch. Sequence control is carried out by (21).

A laser shape measuring instrument (not shown) is disposed outside the die 11 and measures the thickness of the powder molded article W taken out. For example, it receives the reflected light of the laser beam irradiated while moving the powder molded article W, scans the thickness of the powder molded article W from the measurement start end toward the measurement end, detects the shape data, and finishes the measurement from the measurement start end. The thickness data of the powder molded article W during the stage is transmitted to the control unit 80.

For example, as shown in FIG. 6, the control unit 80 includes an input unit 81, a memory 82, an operation unit 83, a hard disk device 84, an output unit 86, A communication line 87 is provided for communicating data of these mutually. The input unit 81 includes an DDV servo drive device 72 for upper punches, a DDV servo drive device for pressure 75, a lower ram drive motor 62M, an upper ram drive motor 73M, and a lower punch DDV type. The servo drive 22 and the laser shape measuring device are connected. The output unit 86 includes a DDV servo drive device 72 for upper punches, a DDV servo drive device for pressure 75, a lower ram drive motor 62M, an upper ram drive motor 73M, and a lower punch DDV. The type servo drive device 22 is connected.

The input unit 81 has, for example, a data input device such as a keyboard (not shown), and outputs the setting and the like to the operation unit 83, and the DDV servo drive device 72 for press punching and the DDV for pressurization. The detection signal of the pressure sensor of the type servo drive device 75 and the pressure sensor of the DDV type servo drive device 22 for lower punches, the encoder of the lower ram drive motor 62M and the upper ram drive motor 73M (not shown) The rotation angle detection signal and the measurement signal from the laser shape measuring instrument are input, and these signals are output to the calculating part 83.

The calculating unit 83 reads the program stored in the ROM of the memory 82 and executes the program. And the calculating part 83 is the operation program data of the powder shaping | molding press 50 stored in the memory 82, and the encoder from the encoder of the DDV-type servo drive device 72 and the ram drive motor 62M for phase punching. A signal for controlling the position, speed, stop operation and the like of the upper punch 31 and the lower ram 61 with respect to the upper punch DDV servo drive device 72 and the lower ram drive motor 62M based on the signal. Outputs

Moreover, the calculating part 83 calculates the load advance amount of each pressurization DDV type servo drive apparatus 75 based on the measurement data of a laser shape measuring instrument with reference to the database 85, and each pressurization DDV. Output to the type servo drive unit 75 is performed. In this embodiment, a four-axis control system (multi-axis control) is possible in that the load advance amounts of the plurality of pressure-type DDV servo drive devices 75 can be independently controlled based on the measurement data from the laser shape measuring device. Method) is preferred.

Moreover, when controlling the load advancement amount of each pressurization DDV servo drive apparatus 75 irrespective of a measurement data for the reason that the pressurization characteristic in powder molding is known, etc., a certain pressurization DDV servo drive apparatus Using master as the master, you may apply the master slave system which controls another pressurized DDV type servo drive apparatus 75 based on the position of a master.

Moreover, it is good also as a structure which outputs the signal regarding the diagonal charge of the lower punch DDV type servo drive apparatus 22, and the vibration generation at the time of charging to the lower punch DDV type servo drive apparatus 22. As shown in FIG.

The output unit 86 transmits the signal from the operation unit 83 to the DDV servo drive device 72 for upper punches, the DDV servo drive device 75 for pressurization, and the DDV servo drive device 22 for lower punches. To the ram drive motor 62M.

In the hard disk device 84, for example, the same database 85 as shown in FIG. 6 is stored.

According to the thickness (measurement data) of the site | part which becomes the object of the powder molded article W, the database 85 has numerical data of the rod advancement amount of the DDV-type servo drive apparatus 75 for pressurization for making it into a target thickness, Each pressing force is configured in the form of a data table. Parameters ΔL1 to ΔL4 in FIG. 7 indicate the amount of advancement of the load of the DDV type servo drive device 75 for pressurization corresponding to the amount of compression of the metal powder P. In FIG.

Next, with reference to FIGS. 8-10B, the operation | movement from filling up the metal powder P in the powder molding apparatus 1 to a pressurization process is demonstrated.

8 and 9 are diagrams for explaining an outline of the operation and action of the powder molding apparatus 1 according to the embodiment.

10A and 10B are lines showing the operation of the powder forming apparatus 1 phase punch 31 (the DDV type servo drive device 72 for image punch and the DDV type servo drive device 75 for pressurization). Drawing. FIG. 10A is a diagram illustrating details of the operation of the image punch 31 in the powder molding cycle. FIG. 10B shows the details of operations of the image punch 31, the image punch DDV servo drive device 72, and the pressure DDV servo drive device 75 in the portion enclosed by the circle K in FIG. 10A. It is a figure which shows.

(1) First, the control part 80 charges the charging part A with the metal powder P by driving the shoebox 90, while the upper punch 31 stops at top dead center (S1). .

(2) Next, the control part 80 outputs the signal which lowers the image punch 31, and each rod of the image punch DDV servo drive device 72 and the pressure DDV servo drive device 75 is carried out. The upper punch plate 34 is lowered by advancing (S2).

At this time, the control part 80 outputs to the pilot pump 78, and opens the prefill valve 75V, and flows a large amount of hydraulic fluid into the DDV type servo drive apparatus 75 for pressurization. In this way, the control part 80 makes the pressurization DDV type servo drive 75 correspond to advance in high speed (low pressure).

Thereby, the rod of the DDV type servo drive device 72 for image punches and the DDV type servo drive device 75 for pressurization advances at high speed, and as shown in FIG. 10A, the image punch 31 falls at high speed. .

(3) Next, before transferring to the pressurization process in which the image punch 31 pressurizes the metal powder P in the filling part A by the DDV type servo drive apparatus 75 for pressurization, the control part 80 is With respect to the DDV type servo drive device 72 for up punching, a signal in which the up-down direction position of the connecting portion 73 is positioned in the forward direction back side position than the up-down position of the pressure connecting portion 76 is output (S3).

As a result, as shown in FIG. 10B, the pressure-connected portion 73 in which the connection portion 73 connected to the rod of the DDV-type servo drive device 72 for punching is connected to the rod of the DDV-type servo drive device 75 for pressurization ( 76), for example, is located upwards by h. Here, FIG. 10B has shown the detail of the timing enclosed by the circle K in FIG. 10A.

In addition, the signal which makes the up-down direction position of the connection part 73 into a position rearward from the up-down direction position of the pressurization connection part 76 is the DDV-type servo drive apparatus 75 for pressurization to at least one of the some pressurization connection part 76. Means a signal for positioning the connection portion 73 and the pressure connection portion 76 so that a force in a direction opposite to the pressing force of the force is generated.

The action in this S3 is as shown in FIG. 9, for example.

(3-1)

The force in the upward direction is applied to the pressure connecting portion 76 by the output to the DDV type servo drive device 72 for image punching in S3 (S31).

(3-2)

In S31, when an upward force is applied to the pressure connecting portion 76, the inclination of the upper punch plate 34 becomes horizontal, for example, and the axis of the upper punch 31 and the axis of the filling portion A are inclined. This is adjusted to almost match (S32).

(3-3)

When the inclination of the upper punch plate 34 is adjusted so that the axis of the upper punch 31 and the axis of the charging section A are substantially coincident, the rod of the pressurized DDV type servo drive device 75 is made of metal in the charging section A. The powder P can be stably moved forward.

As a result, when it moves to a pressurization process, it becomes possible to adjust the amount of compression of the metal powder P sufficiently stable stably by the rod advancement of the DDV type servo drive apparatus 75 for pressurization (S33).

(4) As shown in FIG. 8, when it transfers to a pressurization process, the load advancement amount of the DDV type servo drive apparatus 75 for pressurization is adjusted, and the deflection of the compression amount of the metal powder P is made small (S4). .

(5) Then, the control part 80 outputs to the pilot pump 78, closes the prefill valve 75V, and is pressurized from the hydraulic pump 75P to the DDV type servo drive apparatus 75 for pressurization. The hydraulic powder of the metal powder P is pressurized in the pressurizing process by flowing the working oil of the DDV servo drive device 75 and advancing it at high pressure while adjusting the amount of compression. And when the upper punch 31 reaches bottom dead center, the control part 80 will hold the upper punch 31 at bottom dead center.

Thereafter, the control unit 80 stops driving of the hydraulic pumps 72P and 75P, and stops the pressurization by the DDV-type servo drive device 72 for press punching and the DDV-type servo drive device 75 for pressurization. To reduce the pressure. Next, the control unit 80 discharges the hydraulic pump 72P in the direction in which the rod of the DDV servo drive device 72 for image punching rises, whereby the image punch plate 34 and the image punch 31. To increase. At this time, in the pressurized DDV type servo drive apparatus 75, the hydraulic oil flows in from the hydraulic oil storage part 75S to the side which raises a load with respect to the hydraulic cylinder 75C.

According to the powder shaping | molding apparatus 1, the DDV type servo drive apparatus 75 for pressurization formed in the image punch plate 34 before the image punch 31 starts pressurizing the metal powder P in the filling part A. Since a force in the upward direction is generated in at least one of the plurality of pressure connection portions 76 for connecting the force, the force in the upward direction acts on the DDV servo drive device 75 for pressurization, and each DDV servo drive for pressure is applied. The deflection of the rod forward amount of the device 75 becomes small. As a result, the inclination of the image punch 31 with respect to the charging part A becomes small, and the compression amount of the metal powder P by the pressure DDV type servo drive apparatus 75 after a pressurization process transition is adjusted stably. The deflection of the density distribution can be reduced.

As a result, the precision of a powder sintered article can be improved.

Moreover, since the rod advancing amount of the pressurizing DDV type servo drive apparatus 75 is adjusted, and it adjusts so that the deflection of the compression amount of the metal powder P may become small, the deflection of the density distribution of the powder molded article W can be made small. . As a result, the powder molded article with small deflection of the density distribution can be molded efficiently.

In addition, according to the powder molding apparatus 1, the deflection of the thickness of the molded powder molded article W is accurately measured in a short time by a laser shape measuring instrument without directly contacting the powder molded article W, and the pressure DDV type Since it feeds back to the position control of the servo drive apparatus 75, the deflection of the thickness of the following powdered molded article W can be adjusted easily and efficiently.

In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of invention.

For example, in the said embodiment, although the case where the image punch drive part was the DDV servo drive device 72 for image punches was demonstrated, you may use a ball screw drive device as an image punch drive part. In this case, similarly to the DDV type servo drive device 72 for punching, the connection portion 73 may be configured to output a signal corresponding to the ball screw drive device to the position in the forward direction rearward than the pressure connection portion 76. have.

Moreover, when the upper punch drive part becomes a hydraulic cylinder and the back pressure adjusting means which adjusts the back pressure accompanying advancing of the upper punch 31 is provided in this hydraulic cylinder, at least one of the several pressure coupling part 76 is provided. It is good also as a structure which outputs the signal which generate | occur | produces the force in the direction opposite to the pressing force of the DDV type servo drive apparatus 75 for pressurization by a back pressure to a back pressure adjustment means. In this case, as the back pressure adjusting means, a pressure regulating valve, a flow rate regulating valve, or the like formed in the hydraulic line in which the back pressure occurs when the rod of the hydraulic cylinder lowers the upper punch 31 can be used.

Moreover, in the said embodiment, the powder molding apparatus 1 adjusts the back pressure accompanying advancing of the DDV type servo drive apparatus 72 for ball punches, the ball screw drive device, or an image punch as an image punch drive part. The case where the hydraulic cylinder provided with a back pressure adjustment means was used was demonstrated. However, you may comprise an image punch drive part by other means.

Moreover, in the said embodiment, the case where the powder shaping | molding apparatus 1 is equipped with four pressurization DDV servo drive apparatus 75 was demonstrated. However, it is good also as a structure provided with the some DDV type servo drive apparatus 75 for pressurization other than four, for example.

Moreover, in the said embodiment, the case where the powder molding apparatus 1 is equipped with the laser shape measuring device as a shape measuring means of the powder molded article W was demonstrated. However, for example, a shape measuring device using ultrasonic waves or radiation may be used instead of the laser shape measuring device, and the powder molding apparatus 1 may be configured to have no shape measuring means.

Moreover, in the said embodiment, the case where the amount of advancement of the rod of the DDV type servo drive apparatus 75 for pressurization was demonstrated when there existed a site | part outside the permissible range with respect to the thickness of the powder molded article W. However, without setting an allowable range, it is good also as a structure which adjusts the load advancement amount, for example based on the signal from a laser shape measuring device every time it is pressed.

Moreover, in the said embodiment, when the load advancement amount of each pressurized DDV type servo drive apparatus 75 is calculated, when the calculating part 83 references the database 85 in the control part 80, Explanation was made. However, for example, the calculation unit 83 may calculate the load advance amount based on the set formula.

In the said embodiment, the case where the position control of the lower punch 21 was controlled by the CNC control system which has the screw structure formed in the lower ram drive shaft 62D and the lower ram 61 was demonstrated. However, the lower punch 21 may be operated using a control system other than the CNC control system or a drive device other than the screw structure. Moreover, you may comprise using other position measuring means, such as a linear scale, instead of an encoder.

In the said embodiment, the case where the lower punch 21 was operable by the DDV type servo drive device 22 for lower punches was demonstrated. However, for example, the powder molding apparatus 1 may be configured to not use the DDV type servo drive device 22 for lower punches, and may be configured to lower the die 11 relative to the lower punch 21. You may also

In addition, when the metal part P is filled in the charging part A, it may be set as the structure which obliquely charges or vibrates the metal powder P using the DDV type servo drive device 22 for lower punches. .

In the said embodiment, shaping | molding in the powder shaping | molding apparatus 1 is fixed with the die 11 with respect to the powder shaping | molding press 50, and the upper punch 31 and the lower punch 21 are die 11 It demonstrated about the case implemented by the die-fixing shaping | molding system which advances about. However, the present invention can also be applied to a powder molding apparatus 1 in which molding is performed by a withdrawal molding method.

In the said embodiment, the case where the lower punch 21 and the upper punch 31 were each single was demonstrated. However, any one or both of the lower punch 21 and the upper punch 31 may be configured to include a punch that retreats in multiple steps in the rolling direction, and any of the lower punch 21 and the upper punch 31 may be used. It can also be set as the structure provided with the core rod.

Moreover, in the said embodiment, the case where the powder molded article W was shape | molded using metal powder P as a material powder was demonstrated. However, instead of the metal powder P, cemented carbide powder, ceramic powder, cermet powder, or the like may be used to produce cutting inserts, cutting tools, and various other products.

In the above embodiment, the case where the storage medium for storing the program is a ROM has been described. However, for example, storage means other than ROM, such as a storage medium such as an EP-ROM, a hard disk, a flexible disk, a magneto-optical disk, or a nonvolatile memory card, may be used. In addition, it goes without saying that the well-known method by which the operation | movement of above-mentioned embodiment is implemented by the process in the control part 80 is applicable.

According to the powder molding apparatus and the method for producing a powder molded article according to the present invention, by stably adjusting the rod forwarding amount of the pressurized DDV servo drive device, it is possible to efficiently produce a powder molded article with a small deflection in density distribution. Available.

A: charging part
P: metal powder (material powder)
1: powder forming device
11: die
21: Ha Punch
31: Prize Punch
71: award platen
73: connection
76: pressure connection
72: DDV type servo drive device for image punch (phase punch driver)
75: DDV servo drive device for pressurization

Claims (5)

A die formed with a filling portion filled with the material powder,
A lower punch mounted relative to the die and forming a filling section together with the die;
An upper punch disposed above the die so as to be able to move forward and backward with respect to the live part;
An image punch driver connected to the image punch through a connecting portion to advance and retract the image punch;
An image platen in which the image punch drive unit is formed;
A plurality of pressurizing DDV-type servo drive devices formed on the image platen and connected to the image punches through pressure connection portions disposed at intervals from the connection portion;
A powder molding apparatus comprising a control unit for pressing a material powder in the filling unit by the plurality of pressurizing DDV servo drives after the image punch driving unit advances the image punch.
The control unit,
Powder molding configured to generate a force in a direction opposite to the pressing force of the pressurizing DDV servo drive device to at least one of the plurality of pressurizing connections before the phase punch starts pressurizing the material powder in the filling part. Device. The method of claim 1,
The said image punch drive part is a DDV type servo drive device for image punches,
The control unit,
A powder molding apparatus for outputting a signal for positioning the connecting portion on the rear side in the forward direction than the pressing connecting portion to the image punch drive unit. The method of claim 1,
The upper punch drive unit is a ball screw drive device,
The control unit,
A powder molding apparatus for outputting a signal for positioning the connecting portion on the rear side in the forward direction than the pressing connecting portion to the image punch drive unit. The method of claim 1,
The upper punch drive unit is a hydraulic cylinder, the back pressure adjusting means is formed in the hydraulic cylinder to adjust the back pressure accompanying the advance of the upper punch,
The control unit,
And at least one of the plurality of pressure connecting portions, a signal for generating a force generated by the back pressure to a force in a direction opposite to the pressing force of the pressure DDV servo drive device, to the back pressure adjusting means. A die formed with a filling portion filled with the material powder,
A lower punch mounted relative to the die and forming a filling section together with the die;
An upper punch disposed above the die so as to be able to move forward and backward with respect to the live part;
An image punch driver connected to the image punch through a connecting portion to advance and retract the image punch;
An image platen in which the image punch drive unit is formed;
A plurality of pressurizing DDV-type servo drives formed on the image platen and connected through pressure connecting portions disposed at intervals from the image punching portion and the connecting portion, wherein the image punch driving portion advances the image punches; Thereafter, as a manufacturing method of a powder molded article by a powder molding apparatus configured to pressurize the material powder in the filling section by the plurality of pressurizing DDV servo drives.
And a force in a direction opposite to the pressing force of the pressurizing DDV servo drive device, to at least one of the plurality of pressurizing connections before the phase punch starts pressurizing the material powder in the filling part.

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