JP2004105995A - Hydraulic forming method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic forming method that reduces forming time and enhances productivity in forming a tube stock into a prescribed shape by hydraulic pressure. <P>SOLUTION: For the hydraulic forming method, there are used: a nozzle main body 8 which is arranged relative to a forming mold 7 and which is used for injecting a forming liquid; and a divided nozzle 12 which is attachable to and detachable from the end of the tube stock W and which is equipped with a valve releasable by connection to the nozzle main body 8. The forming liquid 2 is filled into the tube stock W outside the forming mold 7, the divided nozzle 12 is mounted at the end of the tube stock W and sealed hermetically. Then, the tube stock W is put in the forming mold 7, and the valve is turned to an open state by connecting the nozzle main body 8 to the divided nozzle 12 while the forming liquid 2 is jetted from the nozzle main body 8. After that, the tube stock W is formed by adjusting the hydraulic pressure in the tube stock W, thereby reducing forming time in the forming mold 7. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic forming method and a hydraulic forming apparatus for forming a tubular material into a predetermined shape using a molding tool in a state where a working fluid is filled in the tubular material.
[0002]
[Prior art]
As a conventional hydraulic molding, for example, there has been one using a bulge machine shown in FIG. 6 (pipe processing method by Nikkan Kogyo Shimbun, Masanobu Nakamura, pp. 135 and 136). In the illustrated bulge machine, the raw tube A is set in a forming die 101, the raw tube A and the forming die 101 are chucked by a die chuck cylinder 102, and then the raw tube seal cylinder 103 is driven and the raw metal is sealed by a seal fitting 104. Seal the end of tube A. Thereafter, low-pressure oil is sent from the hydraulic pump 105 to the pipe A to push out the internal air. Then, when the air in the raw pipe A has been discharged, the valve of the hydraulic pump 105 is closed and the oil increased in pressure by the pressure intensifier 106 is sent to the raw pipe A, and the raw pipe A is deformed by the pressure. At this time, if necessary, the pipe A is pushed into the center by the pushing cylinder 107, and the internal pressure is adjusted by the control cam and the flow rate adjusting valve 108. Thereby, the base tube A is formed into a predetermined shape in the forming die 101.
[0003]
[Problems to be solved by the invention]
However, in the conventional hydraulic forming as described above, the base tube is set in a forming die, and then the base tube is filled with low-pressure oil, and after the air in the base tube is completely extruded, the booster oil is supplied. Since the supply and the start of molding are performed, the time per cycle from the setting of the raw tube to the completion of the molding becomes long, which is not preferable in terms of productivity. In order to shorten the molding time and improve the productivity, for example, it is conceivable to shorten the oil filling time. In this case, however, the capacity of the hydraulic pump for filling the oil is increased. Therefore, there is a problem that the equipment becomes large and the equipment cost increases.
[0004]
[Object of the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and in forming a pipe into a predetermined shape by hydraulic pressure, a hydraulic forming method and a hydraulic forming method capable of shortening the forming time and increasing productivity. It is intended to provide a device.
[0005]
[Means for Solving the Problems]
The hydraulic forming method of the present invention is a method in which a processing liquid is filled into a pipe material, and the processing is performed with respect to the forming die when forming the pipe material into a predetermined shape using a forming die while adjusting the liquid pressure inside the pipe material. Using a nozzle body for liquid injection and a split nozzle that is detachable from the end of the tube and has a valve that is opened by connection with the nozzle body, the machining liquid is applied inside the tube outside the mold. After filling and attaching a split nozzle to the end of this tube material to seal the inside of the tube material, put the tube material into the mold together with the split nozzle, and connect the nozzle body and the split nozzle while ejecting the working fluid from the nozzle body After opening the valve, the tube is formed while adjusting the liquid pressure inside the tube communicating with the nozzle body via the valve.
[0006]
Further, the hydraulic forming apparatus of the present invention is an apparatus for filling a working fluid into a pipe material and forming the pipe material into a predetermined shape using a forming die while adjusting the liquid pressure inside the pipe material, and A nozzle body for injecting a working fluid, a working fluid filling means for filling the inside of the pipe material with a working fluid outside the mold, and a split nozzle detachable with respect to an end of the pipe material; However, it is characterized in that the valve is provided with a valve which is closed by being connected to the nozzle main body while sealing the inside of the tube material while being attached to the end of the tube material.
[0007]
In the above-described configuration of the hydraulic forming method and the hydraulic forming apparatus, in order to form the pipe into a predetermined shape using the forming die while adjusting the hydraulic pressure inside the pipe, the hydraulic pressure inside the pipe is increased. A method of forming the tube by pressing the tube against the forming die, a method of forming the tube by pressing the forming die against the tube, and a method of combining both can be used. In addition, the position (sealing position) where the end of the pipe material and the split nozzle are in close contact with each other can be exemplified by the end face of the pipe material and / or the inner surface near the end of the pipe material. Well, it is not particularly limited.
[0008]
Effect of the Invention
In the hydraulic forming method of the present invention, the working fluid is filled inside the pipe material outside the forming die, and a split nozzle is attached to an end of the pipe material to seal the inside of the pipe material. throw into. At this time, the air inside the tube is pushed out together with the filling of the working fluid, and the divided nozzle plays a role of a plug after filling with the working fluid, so that the working fluid can be transported to the mold without leaking.
[0009]
After the tube material is put into the mold, the nozzle body and the split nozzle are connected while the processing liquid is jetted from the chisel body, and the valve of the split nozzle is opened. At this time, since the nozzle body and the split nozzle are connected while the processing liquid is ejected from the nozzle body, the processing liquid inside the pipe material does not flow out when the valve of the split nozzle is opened, and the air flow into the pipe material is prevented. Prevent entry. Thereafter, the tube is formed while adjusting the liquid pressure inside the tube connected to the nozzle body via the valve.
[0010]
As described above, in the hydraulic forming method, since the filling of the working fluid into the inside of the tube and the forming of the tube in the forming die are performed separately, the forming time in the forming die becomes short, and the forming of the tube is also shortened. In the case of performing the process continuously, the filling of the working fluid and the molding of the tube material can be performed simultaneously, so that the cycle time from the filling of the working fluid to the completion of the molding can be shortened.
[0011]
Further, in the hydraulic forming apparatus of the present invention, the working fluid filling means provided outside the molding die fills the inside of the tube with the working fluid, and a split nozzle is attached to an end of the tube to seal the inside of the tube. . Thereafter, the tube material is put into a molding die together with the split nozzle. At this time, the air inside the tube is pushed out together with the filling of the working fluid, and the divided nozzle plays a role of a plug after filling with the working fluid, so that the working fluid can be transported to the mold without leaking.
[0012]
Next, in the molding die, the nozzle body and the split nozzle are connected while the processing liquid is jetted from the chisel, and the valve of the split nozzle is opened. At this time, since the nozzle body and the split nozzle are connected while the processing liquid is ejected from the nozzle body, the processing liquid inside the pipe material does not flow out when the valve of the split nozzle is opened, and the air flow into the pipe material is prevented. Prevent entry. Thereafter, the tube is formed while adjusting the liquid pressure inside the tube connected to the nozzle body via the valve.
[0013]
As described above, in the hydraulic forming apparatus, the working fluid filling means and the forming die are separately arranged, and the filling of the working fluid into the inside of the tube material and the forming of the tube material in the forming die are separated from each other. In this case, the molding time in the mold becomes short, and when the tube material is continuously formed, the filling of the working fluid and the molding of the tube material can be performed simultaneously. It is possible to shorten the cycle time from the filling to the completion of the molding.
[0014]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the hydraulic molding method and the hydraulic molding apparatus of the present invention, the molding time in the molding die can be shortened by filling the working fluid in advance outside the molding die and then molding with the molding die. When the molding is continuously performed, the cycle time from the filling of the working fluid to the completion of the molding can be greatly reduced, and the productivity can be increased.
[0015]
【Example】
FIG. 1 is a view for explaining an embodiment of the hydraulic forming method and the hydraulic forming apparatus of the present invention. In this embodiment, for example, a case is shown in which a tubular material W having a circular cross section is used and the intermediate portion is formed in an expanded state.
[0016]
The liquid pressure forming apparatus shown in FIG. 1 is provided with a molding machine 1 and a liquid tank 3 storing a working fluid 2 arranged side by side, and for transferring a pipe W to and from the molding machine 1 on one side of the liquid tank 3. As the transfer means, a loading robot 4 which is a multi-axis control type handling robot is installed. In addition, as shown in FIG. 1 (d), on the opposite side of the liquid tank 3 with the molding machine 1 interposed therebetween, a delivery table 5 for receiving the formed tube W is provided. An unloading robot 6 serving as a handling robot is provided on one side.
[0017]
The molding machine 1 includes a molding die 7 including a plurality of dies 7A and 7B, and a nozzle body 8 for injecting a working fluid into the molding die 7. The molding die 7 opens and closes each of the dies 7A and 7B by a drive mechanism (not shown), and forms a molding space for the tube W between the dies 7A and 7B. The nozzle body 8 is disposed so as to oppose both ends of the tube material W set in the molding die 7, and can be advanced and retracted toward the end of the tube material by driving means 9 constituted by a hydraulic cylinder or the like. In addition, it is connected to a processing fluid supply source 10 shown in FIG.
[0018]
The liquid tank 2 constitutes a working liquid filling means for filling the inside of the tube material W with the working liquid 2 outside the molding die 7, and a jig 11 for positioning the tube material W therein, It has split nozzles 12 and 12 arranged opposite to both ends of the positioned tube material W, and mounting means 13 and 13 for each of the split nozzles 12. All of the jig 11, the split nozzle 12 and the mounting means 13 are processed. It is immersed in the liquid 2. The working liquid is, for example, oil, but water or the like can also be used.
[0019]
The split nozzle 12 is detachable with respect to the end of the tube W, and is provided with a valve that seals the inside of the tube when attached to the end of the tube W and is opened by connection with the nozzle body 8. I have.
[0020]
More specifically, as shown in FIG. 2A, the split nozzle 12 has a main body portion 15 having a flow path 14 for the machining liquid along the axial direction and having an outer peripheral portion in close contact with the tube material W. The main body portion 15 has a tapered surface 15A on the outer peripheral portion, the diameter of which gradually decreases toward the distal end (left side in FIG. 2), and the tapered surface 15A when the distal end is inserted into the tube material. In close contact with the end of the tube material. A valve seat 16 is formed in the middle of the flow passage 14 by an annular inward flange, and the valve seat 16 is provided with a valve 18 for opening and closing an opening 17 which is a part of the flow passage 14. It is.
[0021]
The valve 18 closes the opening 17 of the valve seat 16 from the distal end side of the split nozzle 12, and the support portion 20 is integrally provided via a shaft portion 19 protruding to the base end side of the split nozzle 12, The elastic member 21 interposed between the valve seat 16 and the support portion 20 constantly urges the elastic member 21 in the closing direction, and maintains the closed state of the opening 17. Further, the support portion 20 is a circular plate slidable along the inner surface of the flow passage 14, and a plurality of circular holes 20A as shown in FIG. 2D, holes having an appropriate shape such as a plurality of fan-shaped holes 20B are formed.
[0022]
In the above-described divided nozzle 12, the distal end of the nozzle body 8 contacts the support portion 20 during the connection process with the nozzle body 8, and thereafter, while the elastic member 21 is being compressed, the support portion 20 is compressed. Is pressed, and the valve 18 is opened as shown in FIG. Thereby, the inside of the tube material W and the flow path 8A of the nozzle body 8 communicate with each other via the flow passage 14 of the divided nozzle 12.
[0023]
The attachment means 13 of the divided nozzle 12 is constituted by, for example, means for engaging and disengaging the base end of the divided nozzle 12, a cylinder for driving the engaging and disengaging means forward and backward. In addition, the unloading table 5 is provided with means 22 for removing the split nozzle 12 at positions opposite to both ends of the tube material W. The detaching means 22, like the attaching means 13, is constituted by means for engaging and disengaging the base end of the divided nozzle 12, a cylinder for driving the engaging and disengaging means forward and backward, and the like.
[0024]
In order to perform hydraulic forming of the tube W using the hydraulic forming apparatus having the above-described configuration, the tube W is set on a jig 11 in the liquid tank 3 as shown in FIG. That is, the pipe W is immersed in the processing liquid 2 in the liquid tank 2 and the processing liquid is filled therein. Then, as shown in FIG. 1 (b), after dividing nozzles 12, 12 are attached to both ends of the pipe material W in the working fluid 2 to seal the inside of the pipe material, the loading robot 4 controls the pipe material in the liquid tank 3. W is put into the mold 7 together with the split nozzle 12. At this time, the split nozzle 12 may be configured such that the end portion of the tube material is spread by the tapered surface 15A so that the tapered surface 15A and the inner surface of the end portion of the tube material W are brought into close contact with the entire circumference.
[0025]
At this time, in the hydraulic forming method, since the pipe material W is immersed in the working fluid 2, the working fluid is sunk from the opening end portion which is clearly larger than the nozzle, as compared with a case where the working fluid is filled using a nozzle or the like. The working fluid 2 can be quickly filled with almost no air entrainment. After the filling of the working fluid 2, the end of the pipe W is sealed by the split nozzle 12, and the split nozzle 12 maintains the closed state of the valve 18, so that the pipe W is formed without leaking the working fluid 2. It can be transported to the mold 7.
[0026]
Next, after the tube material W is put into the mold 7, as shown in FIG. 1C, the nozzle body 8 and the divided nozzle 12 are connected while the working liquid 2 is ejected from the nozzle body 8, whereby As shown in FIG. 2B, the valve 18 of the split nozzle 12 is opened. As described above, the connection with the divided nozzle 12 is performed while the machining liquid 2 is ejected from the nozzle body 8, thereby preventing the situation where the machining fluid 2 in the pipe material flows out when the valve 18 of the divided nozzle 12 is opened. And air can be prevented from entering the inside of the tube.
[0027]
Thereafter, in the hydraulic forming method, the forming machine 1 forms the tube W while adjusting the liquid pressure inside the tube connected to the nozzle body 8 via the valve 18. At the time of molding, the next tube W and the divided nozzle 12 are set in the liquid tank 3. Therefore, a plurality of divided nozzles 12 are prepared as two sets attached to one pipe W, so as to be able to cope with continuous forming of the pipe W. The loading of the pipe W and the split nozzle 12 into the liquid tank 3 can also be performed by the loading robot 4.
[0028]
Further, the formed tube material W is conveyed from the forming die 7 to the carry-out table 5 by the carry-out robot 6 as shown in FIG. 1D, and the divided nozzle 12 is removed by the removing means 22. The detached divided nozzle 12 is transported to the liquid tank 3 side. Further, the processing liquid 2 flowing out of the pipe material W at the unloading table 5 can be returned to the liquid tank 2 by, for example, a circulation system 23 having a pump 23A.
[0029]
Here, FIG. 3 shows a flow (a) of the conventional hydraulic forming and a flow (b) of the hydraulic forming of the present invention. In the conventional hydraulic forming, the pipe is set in the forming die in step S101, the nozzle of the forming die is inserted into the pipe in step S102, and the filling of the working fluid is started. In step S103, the air inside the pipe is evacuated. In step S104, molding is performed, and in step S105, the formed tube is taken out. That is, in the conventional hydraulic forming, after setting a pipe material in a forming die, filling of a working fluid, bleeding, and forming are performed.
[0030]
On the other hand, in the hydraulic forming according to the present invention, as the working fluid filling step SA, the working fluid 2 is filled into the pipe material W outside the forming die 7 in step S1, and the pipe end is divided by the split nozzle 12 in step S2. Seal. Then, after the divided nozzle 12 is put into the molding die 7 together with the tube material W, the nozzle main body 8 is connected to the divided nozzle 12 in step S3 as a molding step SB, molding is performed in step S4, and the molded tube material in step S5. Take out W.
[0031]
As described above, in the hydraulic forming method of the present invention, since the filling of the working fluid 2 into the tube and the forming of the tube W in the forming die 7 are separately performed, the forming time in the forming die 7 is short. It becomes. In addition, when the forming of the pipe W is performed continuously, the filling of the working fluid 2 and the forming of the pipe W can be performed simultaneously. Therefore, the cycle from the filling of the working liquid 2 to the completion of the forming is completed. Time can be reduced, and productivity can be increased.
[0032]
Further, in the hydraulic forming method and the hydraulic forming apparatus, since the pipe W is immersed in the processing liquid 2 in the liquid tank 3 as a pre-process of forming, no pump for filling the processing liquid is required, and the pipe W The working fluid 2 can be quickly filled while discharging the air inside, thereby contributing to downsizing of the equipment and reduction of the equipment cost.
[0033]
FIG. 4 is a view for explaining another embodiment of the hydraulic forming method of the present invention. The same components as those in the previous embodiment are denoted by the same reference numerals, and detailed description is omitted.
[0034]
In this embodiment, as shown in FIG. 4 (a), the pipe W is filled with the working fluid 2, and as shown in FIG. 4 (b), divided nozzles 12 are attached to both ends of the pipe W, and FIG. At the stage where the nozzle main body 8 is connected to the divided nozzle 12 of the tube material W put into the molding die 7 as shown in (5), the filling of the processing liquid 2 into the next tube material W in the liquid tank 3 is started.
[0035]
Then, as shown in FIG. 4D, by the time the forming of the previous tube W is completed in the forming die 7, the installation of the split nozzles 12 at both ends of the next tube W is completed. As shown in e), the formed tube W is carried out to the carrying-out stand 5, the next tube W is put into the mold 7, and the next tube W is set in the liquid tank 3.
[0036]
In this way, the steps of filling the pipe W with the working fluid 2, attaching the split nozzle 12, forming the pipe W by the molding die 7, carrying out the formed pipe W, and removing the split nozzle 12 respectively proceed. By doing so, the cycle time can be further reduced, and the productivity can be further increased. The transfer means is not limited to a multi-axis control type handling robot, but may be any transfer device that is linked to the opening and closing of the mold 7.
[0037]
FIG. 5 is a view for explaining still another embodiment of the hydraulic forming apparatus of the present invention. In the hydraulic forming apparatus according to this embodiment, the liquid tank 3 constituting the working liquid filling means has a volume capable of simultaneously charging a plurality of pipes W. A set of jigs 11, a pair of divided nozzles 12 and a mounting means 13 are respectively arranged at three places in the illustrated liquid tank 3, and the three pipes 3 are filled with the processing liquid 2. And the installation of the split nozzle 12 can be performed simultaneously.
[0038]
According to this embodiment, the same effect as in the previous embodiment can be obtained, and moreover, a large number of pipes W filled with the processing liquid 2 and sealed with the divided nozzles 12 can be prepared in advance. The cycle time can be further reduced, and the productivity can be further improved. It should be noted that the number of pipes W that can be charged can be other than three as a matter of course.
[Brief description of the drawings]
FIGS. 1A to 1D are explanatory views showing an embodiment of a hydraulic forming method and a hydraulic forming apparatus according to the present invention in the order of steps.
FIG. 2 is a sectional view (a) showing a state before connection between a divided nozzle and a nozzle body, a sectional view (b) showing a state after connection, a front view (c) showing an example of a support section, and other than the support section. It is a front view (d) which shows the example of.
FIG. 3 is a flowchart (a) showing a conventional hydraulic forming step and a flowchart (b) showing a hydraulic forming step of the present invention.
FIGS. 4A to 4E are explanatory views showing another embodiment of the hydraulic forming method of the present invention in the order of steps.
FIG. 5 is an explanatory view showing another embodiment of the hydraulic forming apparatus of the present invention.
FIG. 6 is a cross-sectional view illustrating a bulge machine used for conventional hydraulic forming.
[Explanation of symbols]
W Tube material 2 Processing liquid 3 Liquid tank (processing liquid filling means)
4 Loading robot (transportation means)
6 Unloading side robot (transportation means)
7 Mold 8 Nozzle main body 12 Split nozzle 14 Flow passage 15 Main body 18 Valve 20 Supporting part 21 Elastic member

Claims (8)

When a working fluid is filled into a pipe material and a pipe material is formed into a predetermined shape using a forming die while adjusting the liquid pressure inside the pipe material, a working fluid injection nozzle body arranged with respect to the forming die and a pipe material Using a split nozzle with a valve that can be attached to and detached from the end of the tube and that is opened by coupling with the nozzle body, the working fluid is filled inside the tube outside the mold, and the end of the tube is After installing the split nozzle and sealing the inside of the tube material, put the tube material into the forming die together with the split nozzle, connect the nozzle body and the split nozzle while ejecting the processing liquid from the nozzle body, open the valve, and then open the valve A hydraulic forming method characterized by forming a tube while adjusting the liquid pressure inside the tube connected to the nozzle body via the nozzle body. When filling the inside of the tube material with the working fluid outside the molding die, submerge the tube material in the working fluid in the liquid tank, fill the inside with the working fluid, and install a split nozzle at the end of the tube material in the working fluid The method of claim 1, wherein: A nozzle body for filling a working fluid into a pipe material and shaping the pipe material into a predetermined shape using a molding die while adjusting the liquid pressure inside the tube material, the nozzle body being arranged with respect to the molding die for injecting a working fluid. A working fluid filling means for filling the inside of the tube material with the working fluid outside the mold, and a split nozzle detachable from an end of the tube material, wherein the split nozzle is attached to the end of the tube material. A hydraulic forming apparatus comprising: a valve that seals the inside of a pipe material and is opened by being connected to a nozzle body. The split nozzle has a main body portion having a flow path of the processing liquid along the axial direction and an outer peripheral portion closely contacting the pipe material, a valve having a support portion with which the nozzle main body abuts and opening and closing the middle of the flow path, and a valve. 4. The hydraulic forming apparatus according to claim 3, further comprising an elastic member biasing in a closing direction, wherein the valve is opened by pressing the supporting portion with the nozzle body when the nozzle body is connected to the nozzle body. The hydraulic forming apparatus according to claim 3, wherein a plurality of divided nozzles are provided as one set of divided nozzles attached to one pipe material. The processing fluid filling means is a means that includes a liquid tank storing the processing fluid, submerges the pipe in the processing fluid, fills the inside with the processing fluid, and attaches a divided nozzle to the end of the pipe in the processing fluid. The hydraulic forming apparatus according to any one of claims 3 to 5, characterized in that: 7. The hydraulic forming apparatus according to claim 6, wherein the liquid tank constituting the working liquid filling means has a volume capable of simultaneously charging a plurality of pipes. The hydraulic forming apparatus according to any one of claims 3 to 7, further comprising conveying means for conveying the pipe material inside and outside the forming die.

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