JP2002292436A - Liquid pressure forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safety countermeasure for operators in liquid pressure forming for a working material, and avoid the occurrence of the trouble of the peripheral facilities. SOLUTION: In the liquid pressure forming device 1, wherein a pipe material 7 in a state of being housed inside a predetermined shaped die comprising a cope 2 and a drag 3 is subjected to liquid pressure forming by feeding by pressure a pressurized liquid inside the pipe material, the cross-sectional shape of the cope 2 and the drag 3 in the vicinity of the die outside opposing to each other interposing the dividing face of the cope and the drag has a recess and projection relationship, a recess 2A is formed on the cope 2, and a projection 3A, whose upper face position becomes higher than the dividing face of the cope and drag, is formed on the drag 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic forming apparatus used for manufacturing, for example, a frame of an automobile.

[0002]

2. Description of the Related Art In recent years, there has been a tendency for hydraulic molding technology to be introduced into the manufacture of the above-mentioned automobile frames and the like. This hydraulic forming technique is also referred to as a hydroforming method, in which a tube material such as a metal tube is housed in a mold having a predetermined shape composed of an upper mold and a lower mold, and a pressurized fluid is press-fitted into the tube material. Is pressed in the axial direction to form a predetermined shape.

FIGS. 6 and 7 schematically show such a hydraulic forming apparatus, and FIG. 7 is a sectional view taken along line BB of FIG.

[0004] The hydraulic forming apparatus 21 includes an upper mold 22 and a lower mold 2.
3 and the cylinders 24 and 25. When manufacturing the product, first, the pipe material 27 as a raw material is directly subjected to preforming such as bending or crushing, and then the upper mold. It is arranged between the lower mold 22 and the lower mold 23. 26A is an inlet for flowing a fluid to be described later into the tube 27, and 26B is an outlet for discharging air from the tube 27.

Next, hydraulic forming nozzles (not shown) provided at the tips of the cylinders 24 and 25 are inserted into the ends of the tube 27, and the nozzles are further pressurized by the cylinders 24 and 25 so that the end of the tube 27 is Fit tightly. Thereafter, the nozzle is further pushed into the mold by the cylinders 24 and 25, and a pressurized fluid supplied from a hydraulic system (not shown) is jetted from the nozzle (the inlet 26A). From the inside to obtain a product (molded product) of a desired shape.

[0006]

Here, the hydraulic pressure required for hydraulic forming using the hydraulic forming apparatus 21 reaches several hundreds to several thousand atmospheres. Therefore, when a crack is generated in the pipe material 27 for some reason during the forming process, the high-pressure fluid ejected from the crack portion first fills the gap 28 between the mold and the pipe material 27, and then continuously increases the high pressure. The fluid in the pressure state is jetted directly to the outside of the mold through the upper and lower division surfaces.

[0007] In such a case, if the pressurized fluid in the extremely high pressure state directly hits a worker working nearby, there is a risk of injury to the worker. In addition, when it hits peripheral equipment, there is also a risk of causing a failure of the equipment.

As a countermeasure against the above, as shown in FIG. 8, a plate member 30 made of an acrylic plate or the like reaching the lower mold 23 across the upper and lower mold separation surfaces is fixed to the end of the upper mold 22 via a fixture 31. By doing so, a measure was taken so that the pressurized fluid ejected from the pipe member 27 by the plate member 30 did not directly hit the operator or peripheral equipment.

However, when such a plate member 30 is provided on the outer peripheral portion of the mold, there is a problem that the work is hindered and the working efficiency is reduced.

Therefore, the present invention solves the above problems,
It has a function to ensure the safety of workers at the time of hydraulic forming of pipe material and to avoid the possibility of causing failure of peripheral equipment,
Moreover, the present invention proposes a hydraulic forming apparatus which does not hinder the operation.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a hydraulic forming apparatus according to the present invention comprises a pipe member housed in a mold having a predetermined shape comprising an upper mold and a lower mold. In the case of press-fitting a pressurized fluid inside and performing hydraulic molding,
The cross-sectional shapes of the upper mold and the lower mold near the outside of the mold that face each other via the upper and lower mold division surfaces have an uneven relationship, a recess is formed in the upper mold, and the upper surface position is higher than the upper and lower mold division surfaces. A projection is formed on the lower die.

Further, in the hydraulic forming apparatus according to the present invention, the cross-sectional shapes of the upper and lower dies near the outside of the mold facing each other via the upper and lower mold division surfaces have an uneven relationship, and a concave portion is formed in the lower mold. A convex portion whose lower surface position is lower than the upper and lower mold separation surfaces is formed on the upper mold.

[0013] Thus, when the pressurized fluid press-fitted into the tube material flows out of the mold through the upper and lower mold split surfaces due to cracks generated in the tube material, the pressurized fluid hits the side wall of the convex portion. After the speed and pressure are dispersed, the fluid is discharged to the outside of the mold, so that the fluid under a high pressurized state does not jet directly to the outside of the mold.

Further, the hydraulic forming apparatus according to the present invention is characterized in that the interval between the upper and lower mold separation surfaces has at least a region larger than another region in a passage from the inside of the mold to the outside of the mold. And

[0015] Thus, when the pressurized fluid press-fitted into the tube material flows out of the mold through the upper and lower mold split surfaces due to cracks generated in the tube material, the pressurized fluid is discharged from the mold inside the mold. In the widened area in the passage toward the outside of the mold, the fluid is discharged to the outside of the mold after the speed and pressure are reduced, so that the fluid under the high pressurized state does not directly blow out to the outside of the mold.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a hydraulic forming apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view schematically showing a hydraulic forming apparatus according to the present invention. FIG. 1 (a) shows a tube member 7 made of, for example, a metal tube preformed in a mold described later. FIG. 1B is a cross-sectional view showing the pipe member 7 which has been hydraulically molded. FIG. 2 shows A in FIG.
2A is a cross-sectional view, and FIG.
Indicates a separated state, and the upper mold 2 is moved downward in the direction of the lower mold 3 to form a mold having a predetermined shape composed of the upper mold 2 and the lower mold 3 shown in FIG. 2B.

The hydraulic forming apparatus 1 includes a mold comprising an upper mold 2 and a lower mold 3 and cylinders 4 and 5. When manufacturing a product, first, a tube material 7 as a raw material is directly bent or bent. After performing preforming such as crushing, the upper mold 2 and the lower mold 3
And between them. 6A is an inlet for flowing a fluid to be described later into the tube 7, and 6B is an outlet for discharging air from the tube 7.

Next, hydraulic forming nozzles (not shown) provided at the tips of the cylinders 4 and 5 are inserted into the ends of the tube 7, and the nozzles are further pressed by the cylinders 4 and 5 to
Tightly fitted with the end of Thereafter, the nozzle is further pushed into the mold by the cylinders 4 and 5, and a pressurized fluid (water, oil, etc.) supplied from a hydraulic system (not shown). In this embodiment, water containing a rust inhibitor is used. Is ejected from the nozzle (inlet 6A), and the pressure of this fluid causes the pipe 7
From the inside to obtain a product (molded product) of a desired shape.

In FIG. 2, the upper mold 2 and the lower mold 3 are overlapped on the upper and lower divided surfaces to form a mold having a predetermined shape, and the tube 7 is accommodated in the mold. Here, a feature of the present invention is that the upper mold 2 and the lower mold 3 that are opposed to each other via the upper and lower mold division surfaces are formed so that the cross-sectional shapes of the upper mold 2 and the lower mold 3 have a concave-convex relationship at a predetermined interval. That is.

A concave portion 2A (upwardly depressed shape) is formed on the lower surface of the upper mold 2 near the outside of the mold, and a predetermined height is formed on the upper surface of the lower mold 3 near the outside of the mold located in a region facing the concave portion 2A. The convex portions 3A having h are formed at predetermined intervals.

A gap formed between the side wall of the concave portion 2A and the side wall of the convex portion 3A detects a pressure abnormality in the pipe material due to a crack in the pipe material 7 by a sensor as described later. Is set arbitrarily based on the amount of liquid ejected within the time until the stoppage.

With the above-described configuration, in the hydraulic forming apparatus 1 according to the present invention, when a crack is generated in the pipe member 7 for some reason during the hydraulic forming, the high-pressure fluid ejected from the crack portion firstly receives the mold and the pipe member 7. And then flows out of the mold through the upper and lower split surfaces.

At this time, as described above, in the hydraulic forming apparatus 1 of the present invention, the recess 2A is formed in the upper mold 2 with a predetermined space in the vicinity of the outside of the mold facing the upper and lower divided surfaces.
Is formed, and the lower mold 3 is formed with the convex portion 3A so that the upper surface position thereof is higher than the upper and lower divided surfaces. Therefore, the highly pressurized fluid flowing out through the upper and lower divided surfaces is First, the speed and pressure of the ejected fluid are dispersed while hitting the defense wall formed by the convex portion 3A. Then, the fluid whose speed and pressure are weakened upon hitting the above-mentioned defense wall is slowly discharged to the outside of the mold after filling the inside of a wide space region formed by the concave portion 2A and the convex portion 3A.

Accordingly, unlike the conventional case, the highly pressurized fluid is not directly ejected to the outside of the mold.
There is no possibility that the highly pressurized fluid directly hits a worker working nearby and injuries the worker. Also,
It is possible to avoid a possibility that a failure of the facility device is caused by hitting a peripheral facility or the like. Further, by devising the shape of the mold itself, it is not necessary to provide the plate member 30 outside the mold as in the related art (shown in FIG. 8), and the working efficiency is not reduced.

Another embodiment of the hydraulic forming apparatus according to the present invention will be described with reference to the drawings. The first
The same components as those of the first embodiment are denoted by the same reference numerals in order to avoid redundant description, and description thereof will be omitted.

First, the feature of the hydraulic forming apparatus 1 according to the second embodiment is that, as shown in FIG. 3, a part of the cross-sectional shape of the upper mold 2 and the lower mold 3 has an uneven relationship. Is the same as in the first embodiment. And the difference is the lower mold 3
A concave portion 3B is formed on the upper surface near the outside of the mold, and a convex portion 2B (a shape protruding downward) is formed at a predetermined interval on the lower surface near the outside of the mold of the upper mold 2 located in a region facing the concave portion 3B. That is. In the gap formed between the side wall of the convex portion 2B and the side wall of the concave portion 3B, as in the first embodiment, a sensor detects an abnormal pressure in the pipe material due to a crack in the pipe material 7 and generates a high hydraulic pressure based thereon. It is arbitrarily set based on the amount of liquid ejected within the time until the device is stopped.

Also in the hydraulic forming apparatus having such a configuration, since the lower surface of the convex portion 2B is formed to be lower than the upper and lower divided surfaces, a high pressurized fluid is applied to the convex portion 2B.
The jet fluid flows and discharges while being distributed, while hitting the defense wall made of B.

Therefore, unlike the related art, the highly pressurized fluid does not directly blow out of the mold.

A feature of the third embodiment is an application of the above-described first embodiment. As shown in FIG. 4, a wall material is provided on the lower mold 3 at a position facing the recess 2A of the upper mold 2. 9 is erected through a fixture 10. Here, by setting the height of the wall member 9 to be the same height h as the height of the convex portion 3A of the first embodiment, even in such a configuration, the heat squirted from the tube member 7 can be obtained. Once the pressurized fluid
In a state where the speed and the pressure of the wall material 9 are weakened when the wall material 9 is hit, a gap (space area) formed between the side wall of the concave portion 2A of the upper mold 2 and the side wall of the wall material 9 is filled, and then slowly out of the mold. Is discharged.

Further, the feature of the fourth embodiment is that, as shown in FIG. 5, the interval between the upper and lower mold separation surfaces is at least a region in the passage from the inside of the mold to the outside of the mold, and a region in another passage. That is, a wider space area 11 is formed.

That is, as described above, a crack is generated in the pipe member 7 for some reason during the hydroforming, and the high-pressure fluid ejected from the crack portion first fills the gap 8 between the mold and the pipe member 7, When the tube material flows out of the mold through the upper and lower split surfaces, a relatively large space region 11 is formed at any position in the passage from the inside of the mold to the outside of the mold, thereby forming the tubular member. The pressurized fluid ejected from 7 hits the wall portions formed in the upper mold 2 and the lower mold 3 by the formation of this space region 11, and the speed and pressure thereof are reduced,
The liquid is slowly discharged to the outside of the mold while remaining in the space area 11.

Incidentally, the space region 11 is provided in the same manner as in the first embodiment, in which the pressure abnormality in the pipe material due to the cracking of the pipe material 7 is detected by the sensor, and based on the detected pressure abnormality, the high hydraulic pressure generating device is stopped. Is set arbitrarily based on the amount of liquid ejected to the nozzle.

As described above, in the fourth embodiment, by forming the predetermined space region 11 in any one of the passages extending from the inside of the mold to the outside of the mold, the conventional highly pressurized fluid can be formed. Ejection directly to the outside of the mold is eliminated.

The shape of the space region 11 can be set arbitrarily. In this embodiment, the cross-sectional shape is rectangular, but may be circular. In addition, the number of space regions 11 is also one. However, the present invention is not limited to this, and it may be formed in multiple stages (a plurality of juxtaposed) in a passage from the inside of the mold to the outside of the mold, and efficiently disperse the speed and pressure of the pressurized fluid. Have a configuration that can be used.

Although the present embodiment has been described with respect to the hydraulic forming of the pipe 7 made of a metal pipe as an example of the workpiece,
The present invention is not limited to this. For example, it may be made of a synthetic resin instead of a metal, or may be a plate-shaped product that is hydraulically molded. Any mechanism can be applied as long as it has a mechanism for hydraulically forming a work material housed in a mold made of pressurized fluid with a pressurized fluid.

[0037]

According to the present invention, even if a crack occurs in a pipe material for some reason during hydroforming,
Since the highly pressurized fluid does not directly blow out of the mold,
Work safety is improved, and failure of peripheral equipment can be avoided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a hydraulic forming apparatus according to the present invention.

FIG. 2 is a cross-sectional view illustrating the hydraulic forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a hydraulic forming apparatus according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a hydraulic forming apparatus according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing a hydraulic forming apparatus according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a conventional hydraulic forming apparatus.

FIG. 7 is a sectional view showing a conventional hydraulic forming apparatus.

FIG. 8 is a sectional view showing a conventional hydraulic forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Hydraulic molding apparatus 2 ... Upper mold 2A ... concave part 2B ... convex part 3 ... Lower mold 3A ... convex part 3B ... concave part 4 ... Cylinder 5 ... Cylinder 6A ...・ Introduction port 7 ・ ・ ・ Tube material 8 ・ ・ ・ Gap 9 ・ ・ ・ Wall material 10 ・ ・ Fixer 11 ・ ・ Space area

Claims (7)

[Claims] 1. A hydraulic forming apparatus for hydraulically forming a workpiece by pressurizing the workpiece with a pressurized fluid in a state where the workpiece is housed in a mold having a predetermined shape composed of an upper mold and a lower mold. A hydraulic forming apparatus, wherein a cross-sectional shape of an upper mold and a lower mold facing the outside of the mold via an upper and lower mold division surface is formed so as to have a concave-convex relationship at a predetermined interval. 2. The liquid according to claim 1, wherein a concave portion is formed in the upper die, and a convex portion whose upper surface position is higher than the upper and lower die dividing surfaces is formed in the lower die. Press forming equipment. 3. The liquid according to claim 1, wherein a concave portion is formed in the lower die, and a convex portion whose lower surface position is lower than the upper and lower die dividing surfaces is formed in the upper die. Press forming equipment. 4. A hydraulic forming apparatus for hydraulically forming a workpiece by pressurizing the workpiece with a pressurized fluid while accommodating the workpiece in a mold having a predetermined shape comprising an upper mold and a lower mold. The cross-sectional shapes of the upper and lower dies near the outside of the mold that face each other via the upper and lower mold division surfaces have an uneven relationship, and a pressurized fluid that presses the workpiece is directed outside the mold through the upper and lower mold division surfaces. When ejecting, a recess is formed in the upper mold so that the pressurized fluid is not directly discharged to the outside,
A hydraulic forming apparatus, wherein the upper surface position is higher than the upper and lower mold dividing surfaces, and a convex portion to which the pressurized fluid is applied is formed in the lower mold. 5. A hydraulic forming apparatus for hydraulically forming a workpiece by pressurizing the workpiece with a pressurized fluid while accommodating the workpiece in a mold having a predetermined shape comprising an upper mold and a lower mold. The cross-sectional shapes of the upper and lower dies near the outside of the mold that face each other via the upper and lower mold division surfaces have an uneven relationship, and a pressurized fluid that presses the workpiece is directed outside the mold through the upper and lower mold division surfaces. When ejecting, a recess is formed in the lower mold so that the pressurized fluid is not directly discharged to the outside,
A hydraulic forming apparatus, wherein the lower surface position is lower than the upper and lower mold dividing surfaces, and a convex portion to which the pressurized fluid is applied is formed on the upper mold. 6. A hydraulic forming apparatus for hydraulically forming a workpiece by pressurizing the workpiece with a pressurized fluid in a state where the workpiece is housed in a mold having a predetermined shape composed of an upper mold and a lower mold. The hydraulic forming apparatus, wherein the interval between the upper and lower mold split surfaces has at least a region wider than another region in a passage from the inside of the mold to the outside of the mold. 7. The hydraulic forming apparatus according to claim 1, wherein the workpiece is a tubular material.