JP2925929B2 - Checking and correcting mold position in powder molding press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for confirming and correcting a relative positional relationship between a plurality of dies such as a die and upper and lower punches in a powder molding press.

[0002]

2. Description of the Related Art As a method of molding a stepped molded product, the applicant has already determined that the compression speed ratio of a plurality of punches for compressing each stepped portion is always equal to the dimensional ratio of each stepped portion of the molded product during the compression process. (Japanese Patent Laid-Open Publication No.
-94900).

[0003] That is, a high-precision molded product is obtained by eliminating movement of powder between powder portions corresponding to each step during compression.

Conventionally, since the finished product is considerably different from the final product due to the movement of the powder between the powder portions corresponding to the respective steps, the conditions such as the compression ratio of each step are changed little by little. It was necessary to re-adjust it, such as performing test punching, but the compression ratio was uniquely determined by the type of powder by the proportional control method described in the above publication, so that when molding, a product as close as possible to the product could be made became. As described above, according to the proportional control method, a molded product as close as possible to the product can be obtained without performing the test-punching, so that the test-punching step can be omitted and the productivity is dramatically improved.

[0005]

However, in the case of the above-mentioned prior art, the trial hitting step can be omitted, but a defective product is produced in large quantities immediately if there is a data input error or an incorrect mounting of the upper and lower punches. Danger. Also, if the upper and lower punches interfere with each other, it may lead to damage to the mold,
In particular, it has become necessary to check the reference length of each punch.

That is, conventionally, there is no method for confirming the position of each punch. For example, if a punch having a different length is installed by mistake when a punch is replaced, the tip position of the punch is not at a regular position. However, if the process directly proceeds to the pressing step, a molded product having completely different dimensions will be formed, and in some cases, the upper and lower punches may interfere with each other and be damaged.

[0007] Even if a punch having a regular size is attached, it is conceivable that the relative positional relationship between the punches may be lost due to a data input error.

Further, the length of the punch changes due to thermal expansion due to heat generation of the punch during continuous operation. In other words, when the forming method by the proportional control is used, the moving speed is controlled so that the moving speed always becomes a constant ratio while measuring the moving amount of each punch. It is difficult to measure the position of the tip, and in practice, it measures a moving part of a punch plate or a punch driving unit that moves integrally with each punch. Therefore, the portion from the measuring section to the punch tip position where the powder is actually pressed is an open loop portion, and the position of the punch tip is not exactly known.

[0009] Such a problem is not limited to a stepped molded product, but also occurs when a molded product having no step is molded.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a pressurizing apparatus which is capable of applying pressure even if there is a mistake in a mold, a mistake in data input, or a thermal expansion. By confirming the relative positional relationship of each mold in the previous stage, it is possible to improve the processing accuracy of the molded product, and to confirm and correct the mold position of the powder molding press that can prevent damage to the mold, etc. Is to provide.

[0011]

To achieve the above object of the Invention The present invention provides a die, a plurality of dies such as the upper and lower punches are moved relative to one another as to molding a powder molded product, the vertical path
Position detectors and punches that monitor the operation of the punch and die.
In a powder molding press having a difference between the tip position of the die and the upper surface of the die , prior to pressing, a mold confirmation position for confirming the relative positional relationship between the ends of each mold is set. Measure the relative positional relationship between the ends of the molds, check whether the measured value is the same as the set value, and correct the relative positional relationship between the ends of each mold so that the measured value is the same as the set value It is characterized by doing.

Such a position confirmation / correction method is such that the powder molded product is a stepped molded product, and the powder portion corresponding to each step portion is pressed so as to always have the same degree of compression during pressing. It is suitable in such a case.

At the mold confirmation position, the position of another mold is confirmed with reference to one of the plurality of molds.
It is characterized by being modified.

As a reference mold, a die, a lower punch, an upper punch, a core, or the like can be used.

In the case where the lower punch is used as a reference and a plurality of lower punches are provided, one of the plurality of lower punches is used as a reference and another lower punch is used as a reference. The position of the punch is checked and corrected together with other dies such as a die and an upper punch.

If the upper punch is used as a reference and a plurality of upper punches are provided, one of the plurality of upper punches is used as a reference and the other upper punch is used as a reference. Check and correct the position of the punch together with other dies such as a die and a lower punch.

After confirming and correcting the relative positional relationship of the mold,
It is characterized in that the relative positional relationship between the molds is confirmed and corrected again after a prescribed time has elapsed or when the prescribed number of molded articles has been reached.

The confirmation and correction of the relative positional relationship between the molds is characterized in that they are manually confirmed and corrected manually.

The confirmation / correction of the relative positional relationship between the dies is automatically confirmed and automatically corrected.

[0020]

According to the present invention, the relative positional relationship between the ends of a plurality of molds is measured at the mold confirmation position, and it is confirmed whether or not the measured value is the same as a predetermined set value. Then, if there is an error, the relative positional relationship between the ends of each mold is corrected so as to be the same as the measured value.

The position of a plurality of dies may be confirmed with reference to the press body other than the dies. You can check the relative position.

For example, when checking at a position where the upper punch has risen to a specified position above the lower punch with reference to the lower punch, the distance from the die surface to the end surface of the upper punch and the distance from the die surface to the end surface of the lower punch Is measured and compared with the set value.

As a reference die, for example, a die is used when the die is fixed to the press body, and a fixed lower punch is used when the die is movable. When all the dies are movable, any one of the dies may be used as a reference and the upper punch may be used as a reference.

In the case where the upper or lower punch is used as a reference and a plurality of upper or lower punches are provided, one of the plurality of upper or lower punches is used as a reference,
The position of the other upper or lower punch with respect to the reference upper or lower punch is checked and corrected together with another mold.

Even if it is confirmed and corrected once, the relative positional relationship changes when it expands or contracts due to a change in air temperature, heat generation during molding and extraction, or a change in temperature when the power source is hydraulic. A similar check is required when the specified time or the specified number of moldings is reached,
If an error occurs, correction is required.

Confirmation / correction of the relative positional relationship between the dies may be performed manually or automatically.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments.

FIG. 3 shows an example of a tool setting section of the powder molding press to which the method for confirming and correcting the mold position of the powder molding press of the present invention is applied.

In this embodiment, a case where a stepped molded product W as shown in FIG. 2F is molded will be described as an example. The molded article W has an outer first step portion W1 and an inner third step W1.
A stepped portion W3 and a second portion connecting the first stepped portion W1 and the third stepped portion W3.
And a stepped portion W2, and the upper and lower end surfaces have a stepped shape corresponding to the difference in the thickness of each portion.

As shown in FIG. 3, the tool set 1 includes:
A plurality of dies, that is, a die 3 having a die hole 2 filled with powder, an upper punch unit 4 and a lower punch unit 5 which are pressed into upper and lower openings of the die 3 are provided. The upper punch unit 4 is connected via a clamper unit 7 to a punch operating unit 6 fixed to the upper ram 9 of the press body.

As shown in detail in FIG. 4, the upper punch unit 4 includes first, second and third upper punches 41, 42 and 43 which are assembled concentrically with each other. The third upper punch 43 is located at the innermost position.
The second upper punch 42 is fitted on the outer periphery of the first upper punch 42, and the first upper punch 41 is fitted on the outer periphery of the second upper punch 42 so as to be slidable with each other. These first, second and third upper punches 41,
Reference numerals 42, 43 are fixed to first, second, and third upper punch holders 44, 45, 46, respectively.

The third upper punch holder 46 is a solid cylindrical member with a flange having a first flange 46a projecting from the upper end thereof. The second upper punch holder 46 has a hollow cylindrical shape and surrounds the outer periphery of the third upper punch holder 46. The holder 45 is fitted, and a hollow cylindrical first upper punch holder 44 is fitted around the outer periphery of the second upper punch holder 45. The first and second upper punch holders 44 and 45 are stepped cylindrical members whose diameters are increased in two stages upward, and have first and second flanges 44a and 44a projecting from upper ends thereof. An upper end of a guide shaft 47 for guiding the entire upper punch unit 4 is fixed to a third flange 44a of the first upper punch holder 44. Further, the third upper punch 43 is provided with a through hole 43b through which the core 54 constituting the mold is inserted.

In order to prevent rotation between the first, second and third upper punch holders 44, 45 and 46, the first upper punch holder 44 and the second upper punch holder 45, and the second upper punch Lock pins 48a and 48b are inserted between the holder 45 and the third upper punch holder 46, and guide the vertical movement by the lock pins 48a and 48b.

First, second and third upper punch holders 4
At the upper ends of the 4, 45, 46, first, second and third insertion portions 81, 82,
83 are provided.

The third insertion portion 83 is a third upper punch holder 4
The third engaging teeth 86 project radially outward at a predetermined pitch in the circumferential direction on the outer periphery of the upper end of the second engaging tooth 86.

The second insertion portion 82 is a second upper punch holder 4
A second engagement tooth 85 is provided on the inner periphery of the upper end of the second insertion portion 82 so as to project radially inward at a predetermined pitch in the circumferential direction. ing.

The first insertion portion 81 is provided with the first upper punch holder 4.
A first engagement tooth 84 is provided on the inner periphery of the upper end of the first insertion portion 81 and protrudes radially inward at a predetermined pitch in the circumferential direction. ing.

A spring 4 is provided between the first upper punch holder 44 and the second upper punch holder 45 and between the second upper punch holder 45 and the third upper punch holder 46, respectively.
9a and 49b are mounted, and this spring 49
a, 49b, the second upper punch holder 45
And the third upper punch holder 46 to prevent the second and third insertion portions 82 and 83 from falling downward in a free state.

On the other hand, the punch operating unit 6 is constructed by assembling first and second upper punch operating means 10 and 11 for operating the first and second upper punches 41 and 42 concentrically with each other. Third operation of the third upper punch 43
The upper punch operating means is constituted by a pressing mechanism of the press body.

In this case, the press body has a cylinder for operating the entire upper punch unit 4 at the upper part. Due to the combination with the position detection sensor, a fluid pressure cylinder such as air pressure, hydraulic pressure, or water pressure is preferable to a mechanical press. Also,
A structure driven by a screw drive mechanism other than the fluid pressure cylinder may be used.

The second upper punch operating means 11 includes a solid second fixing member 12 disposed at the center and a cylindrical second fixing member 12 which is slidably fitted to the outer periphery of the second fixing member 12 in a fluid-tight manner. And two movable members 13. An annular second working chamber 14 into which a working fluid such as pressure oil or air pressure flows is provided in a middle part of the outer periphery of the second fixed member 12, and an inner periphery of the second movable member 13 is provided inside the second working chamber 14. To the second working chamber 14
A second annular piston portion 15 for dividing the inside into two chambers is provided. A solid third adapter 18 is fixed to the lower end of the second fixing member 12.
An annular second adapter 17 is fixed to the lower working end.

The first upper punch operating means 10 includes a cylindrical first fixing member 19 fixed to the upper ram 9 of the press body,
A cylindrical first movable member 20 which is slidably fitted in an inner periphery of the first fixed member 19 in a fluid-tight manner.
A first working chamber 22 into which a working fluid such as pressure oil or air pressure flows is provided in the middle part of the inner periphery of the first fixed member 19, and protrudes into the first working chamber 22 on the outer periphery of the first movable member 20. First
First annular piston portion 21 that partitions working chamber 22 into two chambers
Is provided. An annular first adapter 16 is fixed to a lower end of the first movable member 20.

The first and second upper punch operating means 10, 1
The upper ends of the first fixing member 19 and the second fixing member 12 are connected via a fixing plate 23. That is, the second
The upper end of the fixing member 12 is directly fixed to the fixing plate 23,
The first fixing member 19 is fixed to a fixing plate 23 via a fixing rod 24. The fixed rod 24 is the first and second
It extends along the moving direction of the movable members 20, 13 and is slidably inserted into first and second movable plates 25, 26 connected to the upper ends of the first and second movable members 20, 13. I have.

As shown in FIG. 5, the clamper unit 7 includes first, second, and third clampers 71, 72, and 73 that are assembled concentrically with each other. Third
The clamper 73 is a solid columnar member, and a cylindrical second clamper 72 is fitted around its outer periphery so as to be movable in the axial direction. A cylindrical first clamper 71 is fitted on the outer periphery of the second clamper 72 so as to be movable in the axial direction.

The upper end of the third clamper 73 is connected to the third adapter 8 at the lower end of the second fixing member 12 of the punch operating unit 6.
Is rotatably connected to the

The upper end of the second clamper 72 is rotatably connected to the second adapter 17 at the lower end of the second movable member 13 of the punch operating unit 6.

Further, the upper end of the first clamper 71 is rotatably connected to the first adapter 16 at the lower end of the first movable member 20 of the punch operating unit 6.

On the other hand, at the lower end of the third clamper 73, there is provided a concave third receiving portion 93 with which the third insertion portion 83 at the upper end of the third upper punch holder 46 is engaged. This third
A plurality of third receiving teeth 96 are formed on the inner periphery of the lower end of the receiving portion 93 at a predetermined pitch in the circumferential direction.

A second receiving portion 92 is formed at the lower end of the second clamper 72 so that the second insertion portion 82 at the upper end of the second upper punch holder 45 is engaged. This second receiving part 9
A plurality of second receiving teeth 95 are formed on the outer periphery of the lower end 2 at a predetermined pitch in the circumferential direction.

Further, at the lower end of the first clamper 71, there is provided a first receiving portion 91 with which a first insertion portion 81 at the upper end of the first upper punch holder 44 is engaged.
At the outer circumference of the lower end of the
Receiving teeth 94 are formed.

The first, second, and third clampers 71, 7
The detents 2 and 73 are detented by keys 97 and 98 mounted between the first and second clampers 71 and 72 and between the second and third clampers 72 and 73, and are fixed in the rotation direction. It is movably rotatable in the axial direction. The phases of the first, second, and third receiving teeth 94, 95, and 96 of the first, second, and third clampers 71, 72, and 73 are maintained in a fixed relationship by the rotation preventing members such as the keys 97 and 98. To keep it.

On the other hand, a rotation operating section 30 is provided as rotation means for rotating the clamper unit 7.

As shown in FIG. 5B, the rotation operating section 30 includes a driven tooth 31 formed on the outer periphery of the first clamper 71,
A rack 32 meshing with the driven teeth 31 and a rack 3
And a reciprocating cylinder 33 for driving the first and second members to move forward and backward.
Attached to.

The above-described upper punch unit 4 is assembled to the tool set 1 to which the corresponding lower punch unit 5 is attached.

The tool set 1 includes a die plate 34 having a die 3 to be filled with powder, and a die plate 34.
A first lower punch plate 35 disposed below the first lower punch plate 35 to hold the first lower punch 51; a second lower punch plate 36 disposed below the first lower punch plate 35 to support the second lower punch 52; And a pull-down plate 39 disposed below the fixed plate 38 and connected to the die plate 34 via a tie rod 61. A tie rod 61 is slidably inserted into the first lower punch plate 35 and the second lower punch plate 36.

Then, the first lower punch plate 35 and the second
A first lower punch driving cylinder 62 for operating the first lower punch 51 is mounted between the lower punch plates 36, and a second lower punch 52 is mounted between the second lower punch plate 36 and the fixed plate 38. A second lower punch drive cylinder 63 for operation is mounted. Further, a core rod driving cylinder 67 for reciprocatingly driving the core rod 54 is mounted on the lower surface side of the fixed plate 38. The pull-down plate is also driven by a hydraulic cylinder, not shown, such as hydraulic or pneumatic.

The first lower punch driving cylinder 62 and the second
Each of the lower punch driving cylinders 63 has annular first and second piston rods 64 and 65, and the lower punch driving cylinder 63 has an inner periphery of the second piston rod 65 of the second lower punch driving cylinder 63. The third lower punch holder 57 is inserted, and the second lower punch holder 56 is inserted inside the first piston rod 64 of the first lower punch drive cylinder 62. The core rod drive cylinder 67 has a piston 67a to which the core rod holder 55 that supports the core rod 54 is connected.

The upper punch unit 4 is fixed at the upper end of a guide shaft 47 inserted through the die plate 34, and the upper punch unit 4 is supported by the die plate 34 via the guide shaft 47.

The die plate 34 is provided with an elevating cylinder 66 as an advancing / retreating means for elevating the upper punch unit 4 to advance and retreat with respect to the clamper unit 7.

To connect the upper punch unit of the powder molding press having the above structure, the tool set 1 is mounted in a press body (not shown), the elevating cylinder 66 is operated, and the upper punch unit 4 is raised. The first of the punch units 4
The first, second, and third insertion portions 81, 82, and 83 at the upper ends of the second and third upper punches 41, 42, and 43 are connected to the lower ends of the first, second, and third clampers 71, 72, and 73 of the clamper unit 7. Into the first, second, and third receiving portions 91, 92, and 93.

Next, the drive rack 32 is moved straight by a predetermined amount by the cylinder 33 of the rotation operating section 30, and the clamper unit 7 is rotated via the driven teeth 31 meshing with the drive rack 32, so that each of the first The first, second and third receiving teeth 94, 95 and 96 are engaged with the first, second and third engaging teeth 84, 85 and 86 of the upper punch unit 4. In the case of the illustrated example, since the first, second, and third engagement teeth 84, 85, and 86 are nine, they are engaged when rotated by 20 degrees.

Next, the molding process will be briefly described with reference to FIG.

The molding step includes a mold position confirmation step for confirming and correcting the relative positional relationship of each mold (see FIG. 1), and a step of filling the die hole 2 with the powder P after confirming the mold position ( 2 (a)), a step of transferring the filled powder P (see FIG. 2 (b)), a proportional pressing step (see FIG. 2 (c)), and a step of extracting the molded article 1 after depressurization. (See FIG. 2D).

In the mold position confirmation step, in this embodiment, the lower third punch 53 fixed to the press body is used as a reference.
Check and correct the positional relationship of other molds. In the case of the present embodiment, the dies 3, lower second 2, lower first punches 52, 51, core rod 54, upper The positions of the first, second, and third punches 41, 42, and 43 are set to have a fixed dimensional relationship.

At this mold confirming position, the lower first to third punches 51, 52, 53, the core 54, the die 3, and the upper first to third punches 51, 52, 53.
When the third punches 41, 42, 43 are in a regular positional relationship, the lower first and second punches 51, 52, the end surfaces of the core rod 4 and the die 3 Are set to be the same surface, and the lower end surfaces of the upper first to third punches 41 to 43 are located at a predetermined height H from the upper end surface of the lower third punch 53.

The mold confirmation position may be selected at a certain position in the molding cycle, for example, at a position where the removal of the molded product is completed, to confirm whether or not the proper positional relationship exists at that time. It is preferable to provide a mold position confirmation position separately from the molding stroke, instead of a certain position during the stroke.

That is, since the molding stroke differs depending on the shape and size of the molded product, it is necessary to change the setting position of the mold confirmation position every time a molded product having a different shape and size is hit, which makes the operation troublesome. . That is, as shown in FIG. 2 (g), the ascending position A of the upper first to third punches 51, 52, 53 during the molding cycle corresponding to the extraction completion position.
Is calculated by A = A1 (height of the feeder Fe sliding on the upper surface of the die 3) + A2 (filling depth from the upper surface of the die 3 to the end face of the lower third punch 53) + α (predetermined dimension). This filling depth A2 varies depending on the size of the molded product.

Therefore, in order to be able to confirm at a common mold confirmation position even if the shape and dimensions of the molded product change,
A position having a certain dimensional relationship is set as a mold confirmation position. That is, when exchanging the upper and lower punches and the like in order to strike different molded products, the reference length of the upper and lower punches and the like is not changed, so by setting a predetermined mold confirmation position separately from the molding stroke, the same With this tool set, a common mold checking position can be set regardless of the shape and size of the molded product.

The reference length is a part to be replaced, and the reference length A of the first lower punch 51 is equal to that of the first lower punch 51.
The reference length B of the entire lower punch holder 58 and the second lower punch 52 is up to the middle of the second lower punch 52 and the second lower punch holder 56, and the reference length C of the third lower punch 53 is the third lower punch 53. The reference length D of the core rod 54 is only the core rod 54 up to the middle of the third lower punch holder 57.

The reference lengths A, B, C and D are constant irrespective of the molded product. For the same press, A, B, C, D
If they have the same length, they can be used in common. Each punch is made according to this reference length, but if an error occurs, correction is made at the mold confirmation position.

The reference length E of the first upper punch 41 is equal to the middle of the first upper punch 41 and the first upper punch holder 44, and the reference length F of the second upper punch 42 is equal to the second upper punch 42.
And the third upper punch 43 until the middle of the second upper punch holder.
The reference length G is only the third upper punch 43. Like the lower punch, each punch is made according to the reference length.
If there is an error, correction is made at the mold confirmation position.

Each reference length in the illustrated example is a length obtained by adding each of the upper and lower punches and the punch holder. However, although it is uneconomical, all of the reference length including the punch holder may be made of a material for a mold. .

In the normal position, the lower end surfaces of the first, second, and third upper punches 41, 42, and 43 are flush with each other. Lower punch 51,
The upper end surfaces of 52 and 53 and the core rod 54 are flush with the upper surface of the die 3. The distance H from the upper end surface of the third lower punch 53 to the first to third upper punches 41 to 43 is set to, for example, 100 [mm]. Of course, distance H
It is sufficient to select a dimension that is easy to measure, and an arbitrary dimension can be selected.

Further, the first to third upper punches 41 to 43 need not be flush, and the first to third lower punches 51 to 53,
The die 3 and the core rod 54 need not be flush.

Each of the first to third lower punches 5 to be confirmed
The end shapes of the first to third upper punches 41 to 43 are as shown in FIG.
b, 52b and the projections 51b, 41b, 43b, 53b are provided, so that the flat surface portion 41a avoids the edge portion.
To 43a and 51a to 53a.

At this mold checking position, the movable members 20 and 13 of the first and second upper punch operating means 10 and 11 have a margin so that they can be moved up and down for position adjustment. I have. Further, the first and second lower punch operating means 62, 6
The 3 and the core drive cylinder 67 also have room to be able to move up and down, respectively.

For the checking operation, as shown in FIG. 1, a checking jig using a dial gauge is used.

That is, the checking jig 200 is
The retainer 203 includes a block-shaped retainer 203 formed so that the first and second parts are parallel to each other, and a dial gauge 204 attached to an intermediate portion of the retainer 203 in the vertical direction. The height H of the holder 203 is set to be equal to the regular height dimension between the upper surface 3a of the die 3 and the lower end surface of the upper punch unit 4 at the mold checking position, and the reference point of the measuring element 205 of the dial gauge 204. Is the holder 203
Of the lower end surface 202 of the die 3, that is, the upper surface 3a of the die 3.
It is adjusted to be located in.

The dial gauge 204 has a well-known structure, and includes a gauge main body 206 having a scale and a gauge main body 206.
A measuring element 205 which is provided so as to be able to come and go from the gauge body 20.
In this configuration, the pointer of No. 6 can swing. In the illustrated example, the gauge main body 206 is attached to the holder 203 via the arm 207.

Then, the press is set to the mold confirmation position mode, the lower end surface of the holder 203 is placed on the die upper surface 3a, and the measuring element 205 of the dial gauge 204 is moved to the first, second, and second positions of the lower punch unit 5. 3 Contact the upper end surfaces of the lower punches 51, 52, 53 and the core rod 54 to measure the positions of the upper end surfaces of the first, second, and third lower punches 51, 52, 53 and the core rod 54 from the die upper surface 3a. I do.

If there is an error from the set value, the error is input from the controller, the first and second lower punches 51 and 52 and the core rod 54 are slightly moved up and down, and the tip position is changed to the third lower punch. Adjust so that it is flush with the upper end surface of the 53.

Next, the holder 203 is turned upside down, and the upper end surface 202 is placed on the die upper surface 3a.
With the tracing stylus 205 facing upward, the positions of the lower end surfaces of the first, second, and third upper punches 41, 42, and 43 are checked. If there is an error, the first and second upper punch driving cylinders 10, 11 are checked. The first and second upper punches 41 and 42 are driven by the
The lower end surfaces of the upper punches 41 and 42 are adjusted so as to be flush with the lower end surface of the third upper punch 43 that moves together with the upper ram 9.

If such a checking jig 200 is used, if the checking jig 200 is turned upside down, the end faces of the upper and lower punches 41 to 43 and 51 to 53 can be measured as they are, which is advantageous. It is. Each upper punch 4 at this confirmation position
The height of 1 to 43 is approximately 100 [m] for easy measurement.
m].

After this checking operation, full-scale pressure molding is started. By the confirmation / correction work, the end face positions of the punches of the upper and lower punch units 4 and 5 become completely the same, and if the specified filling depth and pressing position are input, molding can be performed without any trouble.

The first to third upper and lower punches 41 to 4
3, 51 to 53, the position detectors 411 to 431, 511, 521, which monitor the operations of the core rod 54 and the die 3.
541, 301 and the tip positions of the punches and core rods and the top surface 3 of the die are different from each other.
431 to the tips of the upper punches 41 to 43; the position detectors 511, 521, 541 to the tips of the lower punches 51, 52 and the core rod 54;
Components such as punches and adapters from the die to the die upper surface 3 form an open loop.

That is, for the first upper punch 41,
The first movable member 20, the first adapter 16, the first clamper 71, the first punch holder 44, and the first upper punch 41 of the first punch operation cylinder constitute an open portion.

As for the second upper punch 42, the second movable member 13 of the second punch operating cylinder, the second adapter 17,
The second clamper 72, the first punch holder 45, and the second upper punch 42 form an open portion.

As for the third upper punch 43, the second fixing member 12 of the second upper punch operating cylinder and the third adapter 1
8, the third clamper 73, the third upper punch holder 46, and the third upper punch 43 constitute an open portion.

As for the first lower punch 51, the first lower punch 51 and the first lower punch holder 58 constitute an open portion.

As for the second lower punch 52, the second lower punch 52 and the second lower punch holder 57 are open parts.

As for the core rod 54, the core rod 5
4 and the core rod holder 55 become an open part.

The die 3 is provided with a tie rod 61.
Is the open part.

If the length of the open portion changes if the length of the open portion changes due to a change in air temperature, heat generation during molding or removal, or a temperature change in the case where the power source is hydraulic, the length of the open portion changes. A similar check is required when the number is reached. If an error occurs, correction is required.

After the completion of the above-described mold confirmation and correction, the process proceeds to the original molding process.

First, a predetermined amount of powder is filled in the die hole 2, and the filled powder is transferred. The filling depth is determined by each of the first, second, and third steps W1, W2, and W3 of the final molded product W.
Is set to the same ratio as the dimensional ratio.

In the transfer step, as shown in FIG. 2A, the first step W1 and the second step W
The two corresponding powder portions P1 and P2 are sandwiched by the first and second upper and lower punches 41 and 51; and are relatively moved without changing the filling depth. First and second upper and lower punches 4
1, 51; 42, and 52 move at a speed corresponding to the amount of movement, and are controlled so that simultaneous start and simultaneous end are performed, and the powder is not pressurized.

In the pressing step, the first to third upper punch position detectors 411 to 431, the first to third lower punch position detectors 511 to 531 and the core rod position detector 54
The first and second upper punch operating cylinders 10 and 11 and the first and second lower punch operating cylinders 6
2, 63, and further, the core rod operating cylinder 67 is controlled, and the first upper and lower punches 41 and 51;
2, 52: The corresponding powder portions are simultaneously compressed in the axial direction by the third upper and lower punches 43, 53. At this time, compression is performed so that the density of each powder portion is always the same during the compression (see FIG. 1D).

That is, the upper first, second, and third upper punches 4
When the speeds of 1, 42 and 43 are v01, v02 and v03, and the lower first and second third punches 51, 52 and 53 are v11, v12 and v13, (v01-v11) and (v02-v12) , (V03-v13)
Is controlled so as to be always the same as the dimensional ratio of the first, second, and third steps W1, W2, and W3 of the final molded product W during molding.

The position detectors 411-431, 511-
Numerals 531 and 541 are constituted by a combination of a linear scale attached to a movable portion and a sensor attached to a fixed portion on the press body side. In this embodiment, the linear scale of the first upper punch position detector is used. Scale 411a
Denotes a second upper punch position detector 421 on the fixed plate 23.
Of the linear scale 421a on the first movable plate 25,
Linear scale 431 of third upper punch position detector 431
a is fixed to the second movable plate 26, and sensors 411b, 421b, 431b for reading the scales of the linear scale are provided on the press body side in the vicinity of the linear scales 411a, 421a, 431a. The arrangement relationship shown in FIG. 3 is conceptual, and is actually set in the circumferential direction of the tool set so as not to interfere with each other.

The linear scale 511a of the first lower punch position detector 511 is provided on the first punch plate 55 and the linear scale 521a of the second lower punch position detector 521.
Is attached to the second punch plate 56 and the core rod position detector 5.
The linear scale 541a of the core rod holder 55
The linear scale 3 of the die position detector 301 is
01a is a mounting portion 5 provided on the lower ram 39a.
41c, 301c.

In this embodiment, the third lower punch 53 is fixed and the third upper punch 43 is driven by the upper ram 9 of the press. The moving speeds of the third upper and lower punches 41 and 51; 42 and 52 and the upper third punch 43 are set, and the first and second upper punch operating cylinders 10 and 11 and the upper ram 9 are adjusted to reach the set speed. The working cylinder, and further, the first and second lower punch working cylinders 62 and 63 are controlled.

As the pressurizing method, various pressurizing methods such as a single pressing method and a double pressing withdrawal method can be adopted.

When the pressing is completed, the die 3 and the lower first
The second punches 51 and 52 are lowered and the upper punch unit 4 is raised to extract the molded product (see FIG. 2D).

When the removal of the molded product W is completed, the molded product W is conveyed by sliding the die upper surface 3a. This transport
The powder P for the next molding step is pushed laterally by the advancing feeder F to fill it, and at the same time, the powder P for the next molding is filled into the die hole 2 and the process proceeds to the next molding step.

The method of operating these dies is widely applied to presses of a numerical control system such as a full hydraulic servo system, a hydraulic proportional control system, a screw servomotor system, or a system in which a normal mechanical press is controlled by a servomotor. Can be. The mechanical press has a booster mechanism such as a crank, cam, or toggle. For precise control, it is effective to use a non-slip mechanism such as a toothed belt, chain, or gear transmission mechanism for the power transmission unit. It is.

In the above embodiment, the upper punch unit 4 is connected to the punch operating unit 6 via the clamper unit. However, as shown in FIG. 6, the upper punch unit 4 is directly moved upward without the clamper unit. Needless to say, a configuration connected to the punch operation unit 6 is also possible. In the figure, the same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 7 shows a second embodiment of the present invention.

This example shows a case in which a die 211 is stepped by a withdrawal method in which a die is lowered to pressurize and extract a product. In this embodiment, the molded product WA is a single-stage molded product. The number of the lower punch 212 is one, and the second step portion W is provided between the lower punch 212 and the upper punch 213.
A2 is compressed, and the step 211a of the die 211 and the upper punch 2
13, the first stage WA1 is compressed.

Then, during the compression, the first and second stages W
The upper punch 213, the die 211 and the lower punch 212 so that the powder portions corresponding to A1 and WA2 always have the same compression degree.
Speed is set. That is, when the dimensional ratio of the first and second steps WA1 and WA2 of the molded product WA is 1: 2, the speed of the upper punch 213 is VA, the speed of the die 211 is VB, and the speed of the lower punch 212 is Vc. Then, VA: VB: Vc becomes 2:
By setting 1: 0, the first and second steps WA1, W2
The powder portion corresponding to A2 can always be pressed with the same degree of compression, and an extremely precise molded product WA can be obtained.

In order to obtain precise dimensions, the relative positional relationship between the lower punch 212 and the upper punch 213 before pressing is important, and the upper and lower punches 212 and 213 are formed at an appropriate stage in the molding process.
And the relative positional relationship between the dies 211 needs to be confirmed.

In this example as well, at the mold confirmation position,
As shown in (2), the upper end surface of the lower punch 212 is flush with the upper surface of the die 211.

Further, the lower end surface of the upper punch 213 is set at a position separated from the reference surface of the lower punch 212, ie, a predetermined distance from the upper surface of the die 211, and the same dial gauge 204 as in the first embodiment is used. The checking operation can be performed in exactly the same manner using the checking jig 200 that has been used.

FIG. 8 shows a third embodiment of the present invention.

This example also forms a single-stage stepped product similar to that shown in FIG. 7. In this example, a two-pressure system in which a die is fixed is used, and one upper punch 301 and two lower punches 3 are formed.
02, 303 is an example of pressure molding.

In this case, the punches 301, 302,
The speed of 303 is VA for the upper punch 301 and the first lower punch 3
Assuming that 02 is VB and the second lower punch 303 is Vc, VA:
By setting VB: Vc to 1: 0: 1, the first,
The powder portions corresponding to the second steps WA1 and WA2 can always be pressed with the same degree of compression, and an extremely precise molded product can be obtained.

In order to obtain precise dimensions, the relative positional relationship between the upper punch 301, the first and second lower punches 302 and 303, and the die 304 before pressing is important. As shown in FIG. 3E, the upper end surfaces of the first and second lower punches 302 and 303 are flush with the upper surface of the die 304.

Further, the lower end surface of the upper punch 301 is set at a position separated from the reference surface of the lower punches 302 and 303, that is, a predetermined distance from the upper surface of the die 304, and a dial gauge 204 similar to the first embodiment. Confirmation jig 20 using
Confirmation work can be performed in exactly the same manner using 0.

FIG. 9 shows a fourth embodiment of the present invention.

In this embodiment, too, the die goes down to pressurize the product,
With the withdrawal method of extracting, the upper punch 401
Is a case where there are three lower punches 402, 403, and 404, and a stepped molded product having a flat upper surface and three lower surfaces is formed. Then, the first, second, and third steps WB1, W
Assuming that the ratio of the thickness dimensions of B2 and WB3 is 1: 2: 3, the speed of the upper punch 401 is VA, the first and second lower punches 402 and
Assuming that the speed of 403 is VB, Vc, if VA: VB: Vc is set to 3: 2: 1, the first, second, and third step portions WB1,
The powder portions corresponding to WB2 and WB3 can be constantly pressurized during the pressurization so as to have a uniform degree of compression, and a molded product WB having precise dimensions can be obtained.

In order to obtain precise dimensions, the upper punch 401 before pressing, the first, second, and third lower punches 402, 403,
The relative positional relationship between the 404 and the die 405 is important. Also in this example, at the mold confirmation position, the upper positions of the first, second, and third lower punches 402, 403, and 404 as shown in FIG. The end surface is flush with the upper surface of the die 405.

Further, the lower end surface of the upper punch 401 is connected to the reference surface of the lower punches 402, 403, 404, that is, the die 40.
5 It is set at a position away from the top surface by a specified distance,
Confirmation work can be performed in exactly the same manner using a confirmation jig using the same dial gauge 204 as in the first embodiment.

In the second to fourth embodiments, the upper surface is flat, but the lower surface may be flat and the upper surface may be stepped. Alternatively, the upper and lower surfaces may be stepped as in the first embodiment. Of course, it is good.

FIG. 10 shows a fifth embodiment of the present invention. Although the first to fourth embodiments are examples of forming a stepped molded product, the illustrated example has one upper and lower punch,
In addition, this is a case where a molded product having no step is formed.

In order to obtain accurate dimensions, the relative positional relationship between the lower punch 512 and the upper punch 513 before pressing is important, and the upper and lower punches 512, 513 are formed at an appropriate stage in the molding process.
And the relative positional relationship between the dies 511 must be confirmed.

Also in this example, the upper end surface of the lower punch 512 is flush with the upper surface of the die 511 at the mold checking position as shown in FIG.

Further, the lower end surface of the upper punch 513 is set at a position separated from the reference surface of the lower punch 512, that is, a predetermined distance from the upper surface of the die 511, and the same dial gauge 204 as in the first embodiment is used. The checking operation can be performed in exactly the same manner using the checking jig 200 that has been used.

In each of the above embodiments, the position of the mold surface is confirmed by a dial gauge in this embodiment. In addition, a contact type displacement sensor such as an operation transformer, an eddy current type, a laser type, etc. Various sensors such as a non-contact sensor or an air micro can be used. Alternatively, a plurality of dies may be simultaneously measured using a measuring jig incorporating a plurality of sensors in order to simultaneously measure the relative positional relationship between the plurality of dies.

In the case of automatic confirmation, the measurement position of the mold may be determined by using a robot to perform the measurement.

[0129]

As described above, according to the present invention,
Even if there is a mold manufacturing error or data entry error, by checking the relative positional relationship of each mold before pressurization, mold damage can be prevented beforehand and safety can be improved. it is possible to supply a stable quality moldings with improved.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of a method for confirming a mold position of a powder molding press according to the present invention.

2 (a) to 2 (e) are views showing a molding step of the powder molding press of FIG. 1, and FIG. 2 (f) is a longitudinal sectional view showing an example of a molded article; (h) is an enlarged sectional view showing the shape of the end of the punch, and (i) is a view showing the upper punch unit ascending position.

FIG. 3 is a view showing an example of a tool setting section of a powder molding press to which the present invention is applied.

FIG. 4 shows the upper punch unit of FIG. 3;
2A is a longitudinal sectional view, FIG. 2B is a top view, and FIG. 1C is a perspective view of a connection end.

FIG. 5 shows the clamper unit of FIG. 3;
FIG. 1A is a longitudinal sectional view, and FIG. 1B is a plan view of a connection end.

FIG. 6 is a diagram showing a configuration example in which a clamper unit of a tool set unit in FIG. 3 is not used.

FIG. 7 is a diagram showing a second embodiment of the present invention.

FIG. 8 is a diagram showing a third embodiment of the present invention.

FIG. 9 is a diagram showing a fourth embodiment of the present invention.

FIG. 10 is a diagram showing a fifth embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 1 tool set 2 die hole 3 die 3a die upper surface 4 upper punch unit 41, 42, 43 first, second, third upper punch 5 lower punch unit 51, 52, 53 first, second, third lower punch 54 Core rod 6 Punch operation unit 7 Clamper unit 9 Upper ram 10, 11 First and second upper punch operation cylinders 35, 36 First and second lower punch plates 38 Fixed plate 39 Pull down plate 62, 63 First and second lower punch Working cylinder 64 Core rod working cylinder 411, 421, 431 First, second, third upper punch position sensor 511, 521 First, second, third lower punch position sensor 541 Core rod position sensor 301 Die position sensor 200 Confirmation jig 201 upper end face 202 lower end face 203 retainer 204 dial gauge 205 contact point 2 6 gauge body 207 arm W molded article W1 first step portion W2 second step portion W3 third step portion

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B30B 11/02 B21D 37/00 B30B 11/00 B30B 15/02

Claims (11)

(57) [Claims] 1. A die, in which a plurality of molds, such as upper and lower punches are moved relative to each other forming a powder molded product, the upper and lower bread
The position detector monitoring the operation of the
In a powder molding press having a difference between the tip position and the upper surface of the die , prior to pressurization, a mold confirmation position for confirming a relative positional relationship between the ends of each mold is set. Measure the relative positional relationship between the ends of the mold, check whether the measured value is the same as the set value, and correct the relative positional relationship between the ends of each mold so that the measured value is the same as the set value. A method for confirming and correcting a mold position in a powder molding press characterized by the following. 2. The powder molded product according to claim 1, wherein the powder molded product is a step molded product, and a powder portion corresponding to each step is pressed so as to always have the same degree of compression during pressing. How to check and correct mold position in powder molding press. 3. The method according to claim 1, wherein the position of another mold is confirmed and corrected based on one of the plurality of molds at the mold confirmation position. How to confirm and correct the mold position of powder molding press. 4. The method according to claim 3, wherein the reference die is a die. 5. The lower punch is used as a reference die.
Method for confirming and correcting the mold position of the powder molding press described in 1. 6. A die as a reference is an upper punch.
Method for confirming and correcting the mold position of the powder molding press described in 1. 7. When the lower punch is used as a reference and a plurality of lower punches are provided, one of the plurality of lower punches is used as a reference and another lower punch is used as a reference. 6. The method according to claim 5, wherein the position of the lower punch is confirmed and corrected together with another die such as a die and an upper punch. 8. When the upper punch is used as a reference and a plurality of upper punches are provided, one of the plurality of upper punches is used as a reference and the other upper punch is used as a reference. 6. The method according to claim 5, wherein the position of the upper punch is confirmed and corrected together with another die such as a die and a lower punch. 9. After confirming and correcting the relative positional relationship of the mold,
The relative positional relationship between the molds is confirmed and corrected again after a prescribed time has elapsed or when a prescribed number of molded articles has been reached. 9. A method for confirming and correcting a mold position in the powder molding press according to 8. 10. The method of claim 1, 2, 3, 4, 5, 6, 7, 8, or 9 wherein confirmation and correction of the relative positional relationship between the dies is manually confirmed and corrected. Method for confirming and correcting the mold position of the powder molding press described in 1. 11. The method according to claim 1, wherein the confirmation / correction of the relative positional relationship between the dies is automatically confirmed and automatically corrected. Method for confirming and correcting the mold position of the powder molding press described in 1.