JP2006315048A - Hydraulic forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic forming apparatus in which the pressure of fluid which acts on a material to be formed and force by which the peripheral part of the material to be formed is held are respectively independently adjusted corresponding to the progress state of forming. <P>SOLUTION: The hydraulic forming apparatus 1 for forming a plate-shaped material 11 to be formed is provided with: a lower die 2 provided with an fluid tank 21 the upper surface of which is opened and in which the fluid is filled; an upper die 3 which holds the peripheral part of the material 11 to be formed together with the lower die 2; a movable body 4 which is brought into contact with the material 11 to be formed whose peripheral part is held with the upper die 3 and the lower die 2 and moved in a direction in which the movable body is immersed into the liquid tank 21; a holding force adjusting means for adjusting the force by which the material 11 to be formed is held with the upper die 3 and the lower die 2 corresponding to the position of the movable body 4; and a fluid pressure adjusting device for adjusting the pressure of the fluid which is filled into the fluid tank 21 corresponding to the position of the movable body 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique of a hydraulic forming apparatus for forming a plate-shaped object.

  In recent years, environmental standards for automobile exhaust gas have become stricter, and the thickness of the exhaust manifold, one of the components of the exhaust path of automobile exhaust gas, has been reduced to reduce the heat capacity. It has been studied to activate the catalyst provided in the muffler at an early stage and to improve the combustion (removal) effect of soot in the exhaust gas by facilitating the temperature rise in the exhaust path of the automobile due to heat transfer.

When a molded object made of a thin plate-like metal material (hereinafter referred to as “thin plate”) is formed into a complicated shape such as the exhaust manifold, usually, drawing using a mold is performed. One of the molding defects in drawing is “wrinkles”.
Wrinkles occur when distortion in the shrinking direction occurs in the molding object, which is a molding object, and is particularly likely to occur in the case of a thin plate with low surface rigidity.

In general, as a method of preventing “wrinkles” in a drawn product using a mold, (1) a method of previously providing a wrinkle-removing bead at a place where wrinkles occur in the molding, (2) in the mold A method of providing a bead at a place where wrinkles are generated and applying tension to a portion of the molding to be contracted or deformed, or (3) molding a single molding into a final shape by a plurality of moldings. Thus, there is a method of preventing a large shrinkage distortion from occurring in a specific portion of the molding.
However, the method (1) has a problem that it cannot be applied when it is impossible to change the shape of the product for functional or design reasons because a bead is provided on the molding.
In addition, since the method (2) may induce another molding defect such as nodding or cracking in the product, it is possible to determine molding conditions in which neither wrinkles, nodding nor cracking occurs depending on the shape of the product. It can be difficult.
Furthermore, the method (3) has a problem that a so-called shock line dent is likely to occur on the side surface of the molded product. In addition, there is a problem that the number of processes increases and the molding cost increases.
In any of the methods (1), (2), and (3), when forming a thin plate into a complicated shape such as the exhaust manifold, it is difficult to prevent wrinkling of the product after molding.

As a molding apparatus suitable for molding into a complicated shape while preventing wrinkles when molding the thin plate, a hydraulic molding apparatus for molding a plate-shaped object using liquid pressure is known. Yes.
In general, a hydraulic forming apparatus applies pressure to one surface of a plate-shaped object by a liquid such as water or oil, and the other surface of the object is formed into a mold having a predetermined shape. The outer peripheral surface of the molded article is plastically deformed along a mold having a predetermined shape by applying a pressure to the inner peripheral surface of the cylindrical molded article with a liquid. For example, as described in Patent Document 1.

A conventional hydraulic forming apparatus 101 as shown in FIG. 2 is also known.
A conventional hydraulic forming apparatus 101 shown in FIG. 2 includes a die 102 that is open on the top surface and has a liquid tank filled with water, a holder 103 that sandwiches the peripheral edge of the thin plate 111 with the die 102, and a holder 103 and a die 104 which is in contact with a thin plate 111 sandwiched between peripheral edges of the die 102 and moves in a direction to be immersed in the liquid tank of the die 102.
The pins 121 and 121 protruding from the upper surface of the holder 103 are slidably fitted into sliding holes 116 a and 116 a provided in the support member 116, and are externally fitted to the pins 121 and 121. 122 and 122 are interposed between the support member 116 and the holder 103. The support member 116 is fixed to the middle portion of the cylinder rod 115a of the forming cylinder 115 that moves the punch 104 in a direction (downward) for immersing the punch 104 in the liquid tank of the die 102 and in a direction (upward) for retracting from the liquid tank of the die 102.
Japanese Patent Publication No. 6-77785

The conventional hydraulic forming apparatus 101 shown in FIG. 2 has the following problems.
The important factors that determine the quality of molding of the object to be molded by the hydraulic molding apparatus 101 (prevention of wrinkles, cracks, cracks) are the pressure of the water filled in the liquid tank, and the holder 103 and the die 102 are thin plates. The force which clamps the peripheral part of 111 is mentioned.
However, when the holder 103 of the hydraulic forming apparatus 101 abuts the thin plate 111, the hydraulic forming apparatus 101 further protrudes the cylinder rod 115a downward to immerse the punch 104 into the liquid tank of the die 102. The pressure of the water filled in the liquid tank of the dice 102 and the force for clamping the peripheral edge of the thin plate 111 between the holder 103 and the dice 102 are both increased. Therefore, the pressure of the water filled in the liquid tank of the die 102 during molding (in other words, the pressure of water acting on the thin plate 111), and the force for holding the peripheral portion of the thin plate 111 between the holder 103 and the die 102, It was impossible to adjust each independently according to the progress of molding.

  In the present invention, in view of the following situations, the pressure of the liquid acting on the molding and the force for clamping the peripheral edge of the molding can be independently adjusted according to the molding progress. A hydraulic forming apparatus is provided.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

That is, in claim 1,
A hydraulic forming apparatus for forming a plate-shaped object,
A lower mold having a liquid tank that is open on the upper surface and filled with a liquid;
An upper mold that sandwiches the peripheral edge of the molding with the lower mold;
A movable body that abuts on the workpiece having a peripheral edge sandwiched between the upper mold and the lower mold and moves in a direction to be immersed in the liquid tank;
Clamping force adjusting means for adjusting a force for clamping the object to be molded between the upper mold and the lower mold according to the position of the movable body;
Hydraulic pressure adjusting means for adjusting the pressure of the liquid filled in the liquid tank according to the position of the movable body;
It comprises.

In claim 2,
The lower mold is
A lower clamping member that is detachably attached to the opening on the upper surface of the liquid tank and abuts on the molding,
The upper mold is
A base member that moves in a direction approaching the lower mold and a direction moving away from the lower mold;
An upper clamping member that is detachably attached to the base member and abuts against a peripheral edge of the molding;
It comprises.

  As effects of the present invention, the following effects can be obtained.

  In claim 1, the pressure of water acting on the molding and the force for clamping the peripheral edge of the molding are adjusted independently according to the progress of molding, thereby improving the quality of the molded product. It is possible to make it.

  In Claim 2, it is possible to shape | mold the molded product of a different shape using the same hydraulic forming apparatus. Also, by making the lower and upper clamping members, which are the parts that come into contact with the workpiece, of the upper mold and the lower mold detachable, the labor of these replacement operations is reduced (the weight of the replacement member is reduced). It is possible to minimize the number of man-hours for replacement work.

Below, the hydraulic forming apparatus 1 which is one Embodiment of the hydraulic forming apparatus which concerns on this invention using FIG. 1 is demonstrated.
The hydraulic forming apparatus 1 is an apparatus for forming a plate-like thin plate 11.
The thin plate 11 is an embodiment of the plate-shaped object to be molded according to the present invention, and is a thin metal plate.
The thin plate 11 of the present embodiment is a plate-like member made of SUS and having a thickness of 0.4 mm, but the material of the molding is not particularly limited, and is applicable to various metal materials such as titanium, copper, and aluminum. Is possible.
In addition, the thickness of the molded object is not particularly limited, but the hydraulic forming apparatus 1 of the present embodiment has an effect of preventing the generation of wrinkles as the molded object becomes thinner as compared with the conventional hydraulic forming apparatus. Is big.
In addition, although the hydraulic forming apparatus 1 of a present Example is an apparatus which shape | molds the thin plate 11 and obtains the exhaust manifold of the automobile which is a product, this invention is for the use which shape | molds a plate-shaped to-be-molded object in a complicated shape. Widely applicable.

  The hydraulic forming apparatus 1 mainly includes a die 2, a holder 3, a punch 4, a position sensor 5, a clamping force adjusting cylinder 6, a clamping force adjusting cylinder 7, a hydraulic pressure adjusting valve 8, a pressure sensor 9, a control device 10, and the like. It includes a structure for mounting.

First, the structure of the hydroforming apparatus 1 will be described.
The structure of the hydroforming apparatus 1 includes a lower plate 12, an upper plate 13, support columns 14, 14, 14, 14 (the support columns 14, 14 on the front side in FIG. 1 are not shown). It comprises.

The lower plate 12 is a plate-like member that forms the lower part of the structure of the hydraulic forming apparatus 1, and is usually fixed to the ground or the like. The upper plate 13 is a plate-like member that forms the upper part of the structure of the hydraulic forming apparatus 1.
Each of the support columns 14, 14, 14, 14 is a substantially quadrangular prism-shaped member, and one end thereof is fixed to each of the four corners of the upper surface of the lower plate 12, and the other end is fixed to each of the four corners of the lower surface of the upper plate 13. The

Below, the structure of the dice | dies 2 is demonstrated.
The die 2 is an embodiment of a lower mold according to the present invention, and includes a liquid tank 21, a lower ring 22, and the like.

The liquid tank 21 is a container filled with water. The liquid tank 21 of this embodiment includes inner wall plates 21a, 21a, 21a, 21a (in FIG. 1, the inner wall plates 21a, 21a on the front side and the rear side of the page are not shown), outer wall plates 21b, 21b, 21b and 21b (illustration is omitted about the outer wall plates 21b and 21b on the front side and the back side in FIG. 1) and the bottom plate 21c.
The inner wall plates 21 a, 21 a, 21 a, and 21 a are members that form the side walls of the liquid tank 21, and the bottom plate 21 c is a member that forms the bottom surface of the liquid tank 21. The inner wall plates 21a, 21a, 21a, 21a and the bottom plate 21c form a substantially rectangular parallelepiped container opened on the upper surface. The bottom plate 21c is fixed to a substantially central portion of the upper surface of the lower plate 12.
The outer wall plates 21b, 21b, 21b, and 21b are members that form the side walls of the liquid tank 21 disposed outside the inner wall plates 21a, 21a, 21a, and 21a. The molded product (thin plate 11 after molding) is hydraulically pressurized. The water stored in the container formed by the inner wall plates 21a, 21a, 21a, 21a and the bottom plate 21c when the thin plate 11 is taken out from the molding device 1 or another thin plate 11 is set in the hydraulic pressure molding device 1 is hydraulic. Spilling to the outside of the molding apparatus 1 is prevented.
In this embodiment, the liquid tank 21 is filled with water, but the liquid tank 21 may be filled with other liquids such as oil.

The lower ring 22 is an embodiment of the lower clamping member according to the present invention, and is a substantially ring shape that is detachably attached to the opening on the upper surface of the liquid tank 21, that is, the upper end surfaces of the inner wall plates 21a, 21a, 21a, 21a. It is a member. In the case of the present embodiment, the lower ring 22 is detachably attached to the upper end surfaces of the inner wall plates 21a, 21a, 21a, 21a by bolt fastening.
An O-ring 22 a is provided on the lower surface of the lower ring 22. The O-ring 22a has a gap between the lower surface of the lower ring 22 and the upper end surfaces of the inner wall plates 21a, 21a, 21a, 21a when the lower surface of the lower ring 22 comes into contact with the upper end surfaces of the inner wall plates 21a, 21a, 21a, 21a. This prevents water from leaking from the liquid tank 21 to the outside.
The thin plate 11 is placed on the upper surface of the lower ring 22. Accordingly, the lower ring 22 contacts the lower surface of the thin plate 11 on the upper surface thereof. Further, an O-ring 22 b is provided on the upper surface of the lower ring 22. The O-ring 22 b prevents water from leaking from the gap between the upper surface of the lower ring 22 and the lower surface of the thin plate 11.

  In this embodiment, rubber O-ring 22a and O-ring 22b are used for the lower surface and the upper surface of the lower ring 22, respectively, but a metal ring is used instead of the O-ring 22a and O-ring 22b depending on use conditions. It is also possible.

Below, the structure of the holder 3 is demonstrated.
The holder 3 is an embodiment of the upper mold according to the present invention, and sandwiches the peripheral portion of the thin plate 11 with the die 2.
The holder 3 includes a holder base 31, an upper ring 32, and the like.

The holder base 31 is an embodiment of a base member according to the present invention.
The holder base 31 is a main structure of the holder 3 and has a shape like a substantially rectangular parallelepiped container opened on the lower surface. A sliding hole 31 a is formed on the upper surface of the holder base 31.

  The upper ring 32 is an embodiment of the upper clamping member according to the present invention, and is a substantially ring-shaped member that is detachably attached to the lower part of the holder base 31. In this embodiment, the upper ring 32 is detachably attached to the lower part of the holder base 31 by bolt fastening.

  The holder base 31 is fixed to the tip of the cylinder rod 6 a of the clamping force adjusting cylinder 6 and the tip of the cylinder rod 7 a of the clamping force adjusting cylinder 7. The clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 are fixed to the support member 16. The support member 16 is fixed to the middle part of the cylinder rod 15a of the molding cylinder 15.

The forming cylinder 15 is a hydraulic cylinder fixed to the upper surface of the upper plate 13.
A through hole 13 a is formed in a substantially central portion of the upper plate 13, and a cylinder rod 15 a of the forming cylinder 15 projects through the through hole 13 a and projects below the upper plate 13. The forming cylinder 15 extends and moves in a direction (downward) in which the cylinder rod 15a protrudes from the main body, and contracts and moves in a direction (upward) in which it is immersed.
Therefore, the holder 3 (the holder base 31 and the upper ring 32 attached to the holder base 31) is moved by the forming cylinder 15 in a direction approaching the die 2 (downward) and a direction away from the die 2 (upward).
By causing the cylinder rod 15 a of the forming cylinder 15 to protrude downward, the holder 3 moves downward, and the peripheral portion of the thin plate 11 is sandwiched between the holder 3 and the die 2.
At this time, the lower surface of the upper ring 32 abuts on the upper surface side of the peripheral portion of the thin plate 11, and the upper surface of the lower ring 22 abuts on the lower surface side of the peripheral portion of the thin plate 11.

Below, the structure of the punch 4 is demonstrated.
The punch 4 is an embodiment of the movable body according to the present invention, and is detachably attached to the tip of the cylinder rod 15a of the forming cylinder 15.
As the forming cylinder 15 extends, the punch 4 moves downward, and the lower surface and a part of the side surface of the punch 4 abut on the substantially central portion of the upper surface of the thin plate 11 sandwiched between the holder 3 and the die 2. Touch. When the punch 4 further moves downward, the punch 4 is immersed in the liquid tank 21 of the die 2, and the thin plate 11 is plastically deformed along a part of the lower surface and side surface of the punch 4.
At this time, since the volume of the liquid tank 21 is reduced by the amount of the punch 4 immersed, the pressure of the water filled in the liquid tank 21 rises, and the thin plate 11 is applied to the lower surface and part of the side surface of the punch 4 by the pressure. Pressed.

  As described above, in the hydraulic forming apparatus 1 according to the present embodiment, the lower ring 22, the upper ring 32, and the punch 4 that are members in contact with the thin plate 11 are all detachable. Accordingly, a plurality of combinations of lower rings, upper rings, and punches that are different for each shape of the molded product are prepared in advance, and the molded products having different shapes are molded using the same hydraulic molding apparatus 1 by appropriately replacing the combinations. Is possible. Further, by making the lower ring 22, the upper ring 32, and the punch 4 which are members in contact with the thin plate 11 detachable, the labor of the replacement work is reduced (the weight of the replacement member is minimized and replaced). (Reducing work man-hours).

Hereinafter, the position sensor 5 will be described.
The position sensor 5 detects the position of the punch 4, in other words, the forming stroke of the punch 4.
The position sensor 5 of the present embodiment is provided on one of the four support pillars 14, 14, 14, and 14, from the side surface of the support member 16 fixed to the middle part of the forming cylinder 15 toward the side. The position of the punch 4 is detected by detecting the position of the tip of the protruding indicator rod 17.
Specific examples of the position sensor 5 include an optical sensor, a capacitance sensor, and a linear scale. However, other sensors may be used as long as the position of the punch 4 can be detected.

Hereinafter, the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 will be described.
The clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 are hydraulic cylinders fixed to the support member 16 fixed to the middle part of the cylinder rod 15a of the forming cylinder 15 as described above.
The cylinder rod 6 a of the clamping force adjusting cylinder 6 and the cylinder rod 7 a of the clamping force adjusting cylinder 7 protrude downward, and their tip portions are fixed to the upper surface of the holder base 31.
Accordingly, the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 are configured such that the upper ring 32 detachably attached to the lower portion of the holder base 31 is detachably attached to the tip of the cylinder rod 15a of the forming cylinder 15. 4 can be moved relative to the vertical direction.
Further, the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 adjust the hydraulic pressure of the hydraulic oil supplied to the inside thereof so that the upper ring 32 removably attached to the lower part of the holder base 31 is attached to the periphery of the thin plate 11. It is possible to adjust the pressing force on the part, in other words, the force for holding the thin plate 11 between the holder 3 and the die 2.

The forming cylinder 15, the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 in the present embodiment are hydraulic cylinders. However, the same applies to other actuators such as a pneumatic cylinder and an electric motor. The effect of.
In this embodiment, the clamping force adjusting means includes two actuators (the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7). However, the configuration including one actuator may include three or more actuators. It is good also as a structure which comprises an actuator.
Further, in this embodiment, the support member 16 is fixed to the middle part of the cylinder rod 15a of the molding cylinder 15. However, the support member 16 is omitted and the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 are attached to the upper plate 13. It is also possible to fix.

Hereinafter, the hydraulic pressure adjusting valve 8 will be described.
The hydraulic pressure adjusting valve 8 is a valve for adjusting the pressure of water filled in the liquid tank 21.
The hydraulic pressure adjusting valve 8 of this embodiment is an electromagnetic proportional valve capable of adjusting the opening thereof, and the middle of the pipe 18 that passes through the inner wall plate 21a and the outer wall plate 21b and communicates the liquid tank 21 with the outside. Provided in the section.

Hereinafter, the pressure sensor 9 will be described.
The pressure sensor 9 detects the pressure of the water filled in the liquid tank 21.
The pressure sensor 9 of this embodiment is provided in the hydraulic pressure adjustment valve 8.

Below, the control apparatus 10 is demonstrated.
The control device 10 includes a control unit 10a, an input unit 10b, a display unit 10c, and the like.

  The control unit 10a is a program (adjustment force adjustment program) for adjusting the force for holding the thin plate 11 between the holder 3 and the die 2 or a program (adjustment program for adjusting the pressure of water filled in the liquid tank 21). ) Etc., a developing means for expanding the program, etc., a calculating means for performing a predetermined calculation in accordance with the program, a storage means for storing the calculation result and the like.

Further, the storing means of the control unit 10a includes the position of the punch 4 (molding stroke) preset for each type of molded product (combination of the lower ring 22, the upper ring 32 and the punch 4), the holder 3 and the die 2. The information concerning the relationship between the force for clamping the thin plate 11 and the pressure of the water filled in the liquid tank 21 is stored.
In the present embodiment, the information is stored in the storage unit of the control unit 10a. However, the information may be stored in the storage unit of the control unit 10a.

More specifically, the control unit 10a may be configured such that a CPU, ROM, RAM, HDD, or the like is connected by a bus, or may be configured by a one-chip LSI or the like.
The control unit 10a may be a dedicated product, but can also be achieved by using a commercially available personal computer or workstation.

The control unit 10 a is connected to the position sensor 5 and can acquire information related to the position (molding stroke) of the punch 4 detected by the position sensor 5.
The control unit 10 a is connected to the pressure sensor 9 and can acquire information related to the pressure of the water filled in the liquid tank 21 detected by the pressure sensor 9.

  The control unit 10a is connected to a molding cylinder 15 (more precisely, a regulator valve (not shown) that switches a circuit of hydraulic oil supplied to the molding cylinder 15 and adjusts the amount of oil). While contracting and stopping, it is possible to adjust the speed of expansion and contraction of the forming cylinder 15.

The control unit 10a performs the switching of the hydraulic oil circuit supplied to the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7 (more precisely, the clamping oil adjusting cylinder 6 and the clamping force adjusting cylinder 7 and the amount of oil). It is connected to a regulating valve (not shown) and a pressure sensor (not shown) for detecting the pressure of hydraulic oil supplied to the cylinder portions of the clamping force adjusting cylinder 6 and the clamping force adjusting cylinder 7, and the clamping force adjusting cylinder 6 and clamping The force adjusting cylinder 7 is extended, contracted, and stopped, and the holding force adjusting cylinder 6 and the holding force adjusting cylinder 7 press the holder 3 against the die 2, that is, the force for holding the thin plate 11 between the holder 3 and the die 2. It is possible to adjust.
At this time, the control unit 10 a detects information regarding the relationship between the position of the punch 4 (molding stroke) set in advance and the force for holding the thin plate 11 between the holder 3 and the die 2, and the punch 4 detected by the position sensor 5. Based on the information relating to the position (molding stroke), the force for clamping the thin plate 11 between the holder 3 and the die 2 is adjusted.
That is, the control unit 10 a holds the holder in such a manner that the position of the punch 4 (formation stroke) and the force for clamping the thin plate 11 between the holder 3 and the die 2 are maintained according to the position of the punch 4. 3 and the die 2 are used to adjust the force for sandwiching the thin plate 11.
For example, regardless of the position of the punch 4, the force for holding the thin plate 11 between the holder 3 and the die 2 is kept constant at a predetermined value, or when the punch 4 is in a certain region, the holder 3 and the die 2. The force for holding the thin plate 11 is held at the first holding force, and when the position of the punch 4 is in another region, the force for holding the thin plate 11 between the holder 3 and the die 2 is set to the second holding force. It is possible to make various adjustments such as holding the

The control unit 10a is connected to the hydraulic pressure adjusting valve 8, and can adjust the opening degree of the hydraulic pressure adjusting valve 8.
At this time, the control unit 10a detects the position of the punch 4 detected by the position sensor 5 and the information related to the relationship between the preset position of the punch 4 (molding stroke) and the pressure of the water filled in the liquid tank 21. The opening degree of the hydraulic pressure adjusting valve 8 is adjusted based on the information related to the molding stroke) and the information related to the pressure of the water filled in the liquid tank 21 detected by the pressure sensor 9.
That is, the control unit 10a controls the hydraulic pressure adjusting valve so as to maintain the relationship between the preset position of the punch 4 (molding stroke) and the pressure of the water filled in the liquid tank 21 according to the position of the punch 4. Adjust the opening of 8.
For example, the pressure of the water filled in the liquid tank 21 is kept constant at a predetermined value regardless of the position of the punch 4, or the water filled in the liquid tank 21 when the punch 4 is in a certain area. Various adjustments are performed such that the pressure of the water in the liquid tank 21 is maintained at the second pressure when the pressure of the punch 4 is in another region. Is possible.

The input unit 10b is used by an operator or the like to input various data related to the hydraulic forming apparatus 1 to the control unit 10a.
The input unit 10b may be a dedicated product, but can also be achieved using a commercially available keyboard, touch panel, or the like.

The display part 10c displays the data etc. which were input by the input part 10b, the operation | movement condition of the hydraulic forming apparatus 1, etc.
The display unit 10c may be a dedicated product, but can also be achieved using a commercially available monitor, liquid crystal display, or the like.

As described above, the hydraulic forming apparatus 1 is
A hydraulic forming apparatus for forming the thin plate 11,
A die 2 having a liquid tank 21 which is open on the upper surface and filled with a liquid;
A holder 3 for holding the peripheral edge of the thin plate 11 with the die 2;
A punch 4 that abuts against the thin plate 11 sandwiched between the holder 3 and the die 2 and moves in a direction to be immersed in the liquid tank 21;
Clamping force adjusting means for adjusting the force for clamping the thin plate 11 between the holder 3 and the die 2 in accordance with the position of the punch 4;
Hydraulic pressure adjusting means for adjusting the pressure of the water filled in the liquid tank 21 according to the position of the punch 4;
It comprises.
In the case of the present embodiment, the position sensor 5, the clamping force adjustment cylinder 6, the clamping force adjustment cylinder 7, the control unit 10a (the clamping force adjustment program, and the punch 4 preset for each type of molded product). And the position (molding stroke) and information relating to the relationship of the force for holding the thin plate 11 between the holder 3 and the die 2 are stored), and the holding force adjusting means according to the present invention is combined. .
In the case of the present embodiment, the position sensor 5, the pressure sensor 9, the hydraulic pressure adjusting valve 8, and the control unit 10a (the hydraulic pressure adjusting program and the position of the punch 4 set in advance for each type of molded product ( And the information relating to the relationship between the pressure of the water filled in the liquid tank 21 and the pressure of the water filled in the liquid tank 21) correspond to the hydraulic pressure adjusting means according to the present invention.

  By comprising in this way, the pressure of the water which acts on the thin plate 11, and the force which clamps the peripheral part of the thin plate 11 are each adjusted independently according to the progress of shaping | molding, and the quality of a molded article is improved. It is possible to make it. In particular, it contributes to prevention of wrinkles of the molded product.

Moreover, the die 2 of the hydraulic forming apparatus 1 is
A lower ring 22 which is detachably attached to the opening on the upper surface of the liquid tank 21 and abuts against the thin plate 11;
The holder 3 of the hydroforming apparatus 1 is
A holder base 31 that moves in a direction toward and away from the die 2;
An upper ring 32 that is detachably attached to the holder base 31 and abuts against the peripheral edge of the thin plate 11;
It comprises.

  By comprising in this way, it is possible to shape | mold the molded product of a different shape using the same hydraulic forming apparatus 1. FIG. Further, by making the lower ring 22 and the upper ring 32 that are in contact with the thin plate 11 of the holder 3 and the die 2 detachable, it is possible to reduce the labor of the replacement work (the weight of the replacement member is minimized). And reducing the number of man-hours for replacement work.

The schematic diagram which shows one Embodiment of the hydraulic forming apparatus which concerns on this invention. The schematic diagram which shows the conventional hydraulic forming apparatus.

Explanation of symbols

1 Hydraulic forming device 2 Dies (lower mold)
3 Holder (upper mold)
4 Punch (movable body)
11 Thin plate (molded product)
21 liquid tank

Claims (2)

A hydraulic forming apparatus for forming a plate-shaped object,
A lower mold having a liquid tank that is open on the upper surface and filled with a liquid;
An upper mold that sandwiches the peripheral edge of the molding with the lower mold;
A movable body that abuts on the workpiece having a peripheral edge sandwiched between the upper mold and the lower mold and moves in a direction to be immersed in the liquid tank;
Clamping force adjusting means for adjusting a force for clamping the object to be molded between the upper mold and the lower mold according to the position of the movable body;
Hydraulic pressure adjusting means for adjusting the pressure of the liquid filled in the liquid tank according to the position of the movable body;
A hydraulic forming apparatus comprising: The lower mold is
A lower clamping member that is detachably attached to the opening on the upper surface of the liquid tank and abuts on the molding,
The upper mold is
A base member that moves in a direction approaching the lower mold and a direction moving away from the lower mold;
An upper clamping member that is detachably attached to the base member and abuts against a peripheral edge of the molding;
The hydroforming apparatus according to claim 1, comprising:

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