KR20110064521A - Molding apparatus for hydroforming and molding method for hydroforming using it - Google Patents

Abstract

PURPOSE: Hydroforming molding device and method are provided to prevent the damage to the hydroforming molding device by preventing of oil leakage from a target. CONSTITUTION: A hydroforming molding device comprises a molding unit(200), a compressing unit(300), a sensor unit(400) and a control unit(500). The molding unit forms a molding space for a target. The compressing unit enables a punch to be inserted into the opening of the target on the molding unit, sends oil to the inner space of the target closed by the punch to expand the target. The sensor unit senses the contact state of the punch with the target and the insertion state of the punch into the target. The control unit controls the driving of the molding unit and compares the sensed states with reference states to control the driving of the compressing unit.

Description

Hydroforming mold apparatus and hydroforming mold method using same {Molding apparatus for hydroforming and molding method for hydroforming using it}

The present invention relates to a hydroforming mold apparatus and a hydroforming mold method using the same. In particular, the present invention relates to a hydroforming mold apparatus capable of stably molding a workpiece and a hydroforming mold method using the same.

In general, hydroforming is one of the special processing methods for mechanical sheet metal in which the workpiece is expanded by using hydraulic pressure or pneumatic pressure. Such a hydroforming processing method can be used to reduce the weight of the components in the process of manufacturing the parts and at the same time improve the stability of the parts have been widely used in the automotive industry.

The automated process to which the hydroforming processing method is applied is a bending process of bending a workpiece such as a pipe into a certain shape, and a hydroforming that sets the bent workpiece to a mold apparatus and expands it by hydraulic or pneumatic molding. A hydroforming process and a finishing process of trimming, cutting, washing and finalizing the enlarged molded workpiece. Here, the hydroforming process transfers and sets the workpiece after the bending process into a mold, and seals the open part of the set workpiece with a punch, which is a sealing means, to the interior space of the workpiece. And a molding step of filling the high-pressure molding oil or molding gas to enlarge the workpiece.

By the way, in the past, the drive distance of the punch which seals the open part of a to-be-processed object in the hydroforming automation process was always set constantly. For this reason, it is difficult to respond appropriately when the workpiece is deformed due to the influence of a working environment such as temperature or humidity, an unexpected shock, or when the workpiece is not accurately seated at the setting position of the mold by the conveying means. Thus, conventionally, the workpiece is not completely sealed when the workpiece is deformed or is not set correctly in the setting position. That is, molding oil or the like could not be properly filled in the inner space of the workpiece.

In addition, there is a problem in that the generation of defective products, such as crushing or bursting of a certain portion of the workpiece is excessively enlarged due to an excessive increase in a specific part of the workpiece in the unstable filling of molding oil and the like.

In addition, there is a problem in that the molding oil filled inside the workpiece flows into the mold to damage the mold surface or to damage the surrounding mold apparatus. Therefore, the maintenance cost for the maintenance and repair of the hydroforming mold apparatus increases, and the maintenance work of the mold apparatus is additionally required. That is, there is a problem in that the working time required for the hydroforming process increases and the work efficiency and productivity decrease.

The present invention provides a hydroforming mold apparatus and a mold method capable of completely sealing an open portion of a workpiece in an automated hydroforming process.

The present invention detects and judges a contact state and a sealing state of a punch to seal an open portion of a workpiece even when the workpiece set in the mold is deformed or departed from the correct setting position in an automated hydroforming process, and thus the workpiece is opened. It provides a hydroforming mold apparatus and a mold method that can completely seal the site.

The hydroforming mold apparatus according to an embodiment of the present invention drives the mold means for providing a molding space of the workpiece, and the punch is inserted into the open portion of the workpiece set in the mold means, and closed by the punch. A pressurizing means for injecting molding oil into the inner space of the workpiece to expand and mold the workpiece, and detecting a contact state between the punch and the workpiece, and closing the punch into an open portion of the workpiece. A sensor means for sensing a state and a control means for controlling driving of the mold means, and controlling the driving of the pressing means by comparing and determining the contact state and the sealed state with a set reference contact state and a reference sealed state, respectively. do.

In addition, the hydroforming mold method according to an embodiment of the present invention comprises the steps of setting the workpiece to be expanded-molded in the mold means, and the opening of the workpiece to correspond to the deformation of the workpiece and the change of the setting position; Detecting a contact state and a sealed state of the punch to be sealed, and closing the open part of the workpiece through driving control of the punch in comparison with the set reference contact state and the reference sealed state, respectively, and the inside of the closed workpiece Injecting molding oil into the space to expand the workpiece.

According to the embodiment of the present invention, the workpiece may be appropriately deformed during the hydroforming automation process when the workpiece is minutely deformed or fails to be seated at the correct seating position in the mold. That is, by using a sensor means such as a contact sensor and a pressure sensor, the contact between the punch driven horizontally from the side of the mold and the workpiece seated in the mold is detected, and the internal pressure of the cylinder driving the punch to seal the workpiece. By detecting and judging, the open part of the workpiece can be completely sealed.

Therefore, in the process of hydroforming the workpiece, the occurrence of defective products such as crushing or bursting of a part can be prevented, thereby improving productivity of the hydroforming process.

In addition, by preventing the outflow of the molding oil and the like filled in the workpiece, it is possible to prevent damage or breakage of the hydroforming mold apparatus including the mold. Therefore, it is possible to reduce the management cost required for the maintenance and repair of the hydroforming mold apparatus, and the maintenance work caused by the outflow of the molding oil does not occur, thereby improving work efficiency.

Hereinafter, with reference to the accompanying drawings will be described an embodiment according to the present invention in more detail. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. Like reference numerals in the drawings refer to like elements.

1 is a block diagram of a hydroforming mold apparatus according to an embodiment of the present invention, Figure 2 is a view showing a molding state using the hydroforming mold apparatus shown in Figure 1, Figures 3 and 4 in the present invention FIG. 5 is a view schematically showing a contact state of a punch detected in the hydroforming mold apparatus, and FIG. 5 is a view schematically showing a closed state of the punch detected in the hydroforming mold apparatus according to the present invention.

1 to 5, the hydroforming mold apparatus 100 according to an embodiment of the present invention and the mold means 200 for providing a molding space (S ₁ ) for expanding the workpiece 10 and To reciprocally drive at least one punch 310 (310a, 310b) inserted into the open portion 12 so that the open portion 12 (12a, 12b) of the workpiece 10 is sealed, the interior of the workpiece 10 Pressing means 300 for expanding the workpiece 10 by injecting a high-pressure molding oil H (see FIG. 2) into the space S ₂ , and the moment when the punch 310 contacts the workpiece 10. To control the driving of the sensor means 400 and the mold means 200 for detecting a contact state and a sealed state in which the punch 310 is inserted into the open portion 12 of the workpiece 10, and the sensor means 400. The driving state of the pressurizing means 300 is compared and judged by the contact state and the sealed state of the punch 310 sensed by the reference contact state and the standard sealed state, respectively. Control means 500 for controlling the. (In the present invention, the sensor means 400 detects the deformation of the workpiece 10 set in the mold means 200 and the change of the setting position, and thereby the control means 500 opens the workpiece 10. It is characterized by adjusting the driving distance of the punch 310 to seal the portion 12.)

In an embodiment of the present invention, a pipe, such as a pipe, is used as the workpiece 10, and two punches 310a and 310b are applied to seal open ends of the pipe. On the other hand, the pipe member may be formed in a linear form in which the open portion is formed on the opposite side, it may be formed so that the open portion is directed in various directions through the bending process. At this time, the pressing means 300 is disposed on the side of the mold means 200 in the direction of the open portion 12 of the workpiece 10.

The mold means 200 receives the workpiece 10 which has been subjected to the bending process during the automation of the hydroforming process and is transferred to a molding space S ₁ formed therein by being transferred through a transfer means (not shown) such as a robot. To this end, the mold means 200 is composed of a plurality of molds (210, 220) that can be spaced apart in the vertical direction (y direction) or horizontal direction (x direction). (In one embodiment of the present invention, a plurality of molds 210 and 220 of the mold means 200 are positioned up and down.)

When the workpiece 10 to be expanded and formed in the space between the plurality of molds 210 and 220, that is, the molding space S ₁ , is accurately seated in the setting position P _s (see FIG. 4), the plurality of molds 210 and 220. ) Is engaged to secure the workpiece 10. When expansion of the workpiece 10 is performed in such a state, the range of the molding shape is limited by the mold means 200. (In the embodiment of the present invention, the position where the workpiece 10 is symmetrically seated on the center line Y of the mold means 200 is set to the setting position P _s in the normal state.)

Looking at the detailed configuration of the mold means 200 according to an embodiment of the present invention, the mold means 200 is fixed to the ground, the first molding to limit the deformation of the shape during expansion molding of the workpiece 10 The groove 212 and the first punch groove 214 into which the punch 310 is inserted are driven in the up and down direction (y direction) from the upper side of the lower mold 210 and the lower mold 210. In response to the first molding groove 212, the second molding groove 222 for limiting the deformation of the shape when expanding the workpiece 10 and the punch 310 corresponding to the first punch groove 224 are formed. The second punch groove 224 to be inserted includes a mold driving part 230 for driving the upper mold 220 up and down in response to a driving command of the upper mold 220 and the control means 500 formed on the lower surface.

Here, in the state where the upper mold 220 and the lower mold 210 are engaged, the first molding groove 212 and the second molding groove 222 form one molding space S ₁ , and the first punch groove ( The insertion passage of the complete punch 310 is formed by the 214 and the second punch groove 224. In one embodiment of the present invention, since two open portions 12; 12a and 12b of the workpiece 10 are formed, two punches 310a and 310b may be inserted into both sides of the molding space S ₁ , respectively. Punch grooves 214 and 224 are formed at both sides of the forming grooves 212 and 222 so as to be formed.

The workpiece 10 set in the molding space S ₁ inside the mold means 200 configured as described above may be minutely deformed or may not be seated at an accurate setting position in an automatic hydroforming process.

That is, as shown in FIG. 3, the length of the steady state (L _s ; see FIG. 3 (a)) may be changed from the length of the abnormal state (L ₁ ; see FIG. 3 (b)), as shown in FIG. 4. As can be seen, the workpiece 10 may not be seated at the normal setting position (P _s ; see Fig. 4 (a)) and may be biased to one side to be seated at the abnormal setting position (P ₁ , P ₂ ; see Fig. 4 (b)). Can be.

Hydroforming mold apparatus 100 according to an embodiment of the present invention is the length change (length change from L _s to L ₁ ) and the setting position according to the deformation of the workpiece 10 as shown in Figure 3 and 4 Sensor means 400 is provided for detecting a change in (change from P _s symmetric state to P ₁ , P ₂ deflected state).

The sensor means 400 detects the pressing force F ₁ (see FIG. 2) transmitted to the punch 310 at the moment when the punch 310 contacts the workpiece 10 as the 'contact state' of the punch 310 to punch the punch 310. driving distance of _{(310) (L 2, L} 3; reference 3 (b) too) and a contact sensor 410 for measuring. Here, the driving distances L ₂ and L ₃ of the punch 310 are distances driven until the punch 310 enters the mold means 200 and contacts the workpiece 10.

In addition, the sensor means 400 is a pressurized cylinder that pushes the punch 310 to the open portion 12 of the workpiece 10 while the punch 310 is inserted into the open portion 12 of the workpiece 10. Pressure sensor 420 that detects the driving force F ₂ (see FIG. 2) inside the 320 as a 'closed state' of the punch 310 and checks the insertion distance M ₁ (see FIG. 5) of the punch 310. ).

Variables (signals) of the 'contact state' and 'closed state' of the punch 310 sensed by the contact sensor 410 and the pressure sensor 420 are transmitted to the control means 500.

The control means 500 is a workpiece ( _s ) placed on the mold means 200 by comparing the contact state detected by the contact sensor 410 of the sensor means 400 with a preset reference contact state L _s , P _s ( The length L ₁ and the setting positions P ₁ and P _{2 of 10} ) are judged. That is, since the driving distance (L ₂ , L ₃ ) of the punch 310 located on both sides of the workpiece 10 at the moment when the punch 310 is in contact with the workpiece 10, the constant size (L _m The length L1 of the workpiece 10 set in the mold means 200 of the can be measured as shown in Equation 1 below.

L ₁ = L _m- (L ₂ + L ₃ )

Also, the difference between the driving distances L ₂ and L ₃ of the punches 310a and 310b which are individually driven on both sides of the workpiece 10 is checked to set the positions P ₁ and P ₂ of the workpiece 10. It can be confirmed as shown in [Equation 2] below.

P ₁ = L _m / 2-L ₂ , P ₂ = L _m / 2-L ₃

In one embodiment of the present invention, the contact sensor 410 is provided between the cylinder rod 322 and the expansion bar connecting plate 330, the pressing force (F ₁ ) transmitted to the punch 310 is the expansion bar 340 and The expansion bar is connected to the contact sensor 410 via the connecting plate 330.

On the other hand, the insertion degree of the punch 310 inserted into the open portion 12 of the workpiece 10 can be confirmed through a change in the driving force F ₂ measured by the pressure sensor 420.

That is, the driving force F ₂ of the pressure cylinder 320 sensed by the pressure sensor 420 is the insertion distance M ₁ to what extent the punch 310 is inserted into the open portion 12 of the workpiece 10. Used to determine For example, in the process of inserting the punch 310, the driving force F ₂ inside the pressurizing cylinder 320 increases, and when the punch 310 is completely inserted into the workpiece 10, the driving force F ₂ is increased. No more rise That is, when no change occurs in the driving force F ₂ measured by the pressure sensor 420, it may be determined that the insertion distance M ₁ has reached the reference insertion distance M _s .

Here, the set values of the reference contact state (L _s , P _s ) and the reference closed state (M _s ) are input and stored by the operator in the control means before the start of the hydroforming process.

The pressurizing means 300 reciprocally drives the punch 310 sealed in the open portion 12 of the workpiece 10 set in the mold means 200 in response to a driving command of the control means 500. In addition, a high-pressure molding oil (H) is injected into the internal space S ₂ of the workpiece 10 through the first passage 312 formed in the punch 310 to expand the workpiece 10.

To this end, the pressurizing means 300 reciprocally drives the cylinder rod 322 toward the expansion pipe forming space S ₁ from the outside of the mold means 200, and the driving force F through the pressure sensor 420 provided at one side. ₂ ) is engaged with the contact sensor 410 on one end surface of the cylinder rod 322 along the longitudinal direction (x direction) of the pressurized cylinder 320 and the cylinder rod 322 is measured, and the high pressure molding The second passage 332 receiving the oil (H) is coupled to one end of the extension bar connecting plate 330 and the punch 310 formed to penetrate the inside of the body, and at the other end of the extension bar connecting plate 330. The other end is supported, and the second passage 332 and the third passage 342 communicating with the first passage 312 formed in the punch 310 are formed to penetrate along the longitudinal direction (x direction) of the body. Bar 340.

In this embodiment, the pressure cylinder 320 can reliably drive the cylinder rod 322 by using a hydraulic method. Of course, if the reciprocating drive of the cylinder rod 322 can be precisely controlled, it is of course possible to use a pneumatic or other type of cylinder.

In addition, the pressurizing means 300 is provided with a drive source 350 for driving the pressurizing cylinder 320 and a supply source 360 for supplying high-pressure molding oil H on one side of the mold means 200. .

Hereinafter, the hydroforming mold method using the hydroforming mold apparatus according to the embodiment of the present invention will be described.

6 and 7 are a flow chart showing a hydroforming mold method according to an embodiment of the present invention, Figures 8 to 11 is a view showing a driving state of the hydroforming mold apparatus according to the flow chart shown in FIG.

6 to 11, the hydroforming mold method according to an embodiment of the present invention is the step of setting the workpiece to be expanded-molded in the mold means (S110; see FIGS. 8 and 9), and deformation of the workpiece And detecting a contact state and a sealing state of the punch for closing the open part of the workpiece so as to correspond to a change in the setting position, and opening the workpiece by controlling the driving of the punch in comparison with the preset reference contact state and the reference closed state, respectively. Sealing the site (S120; see FIG. 10) and expanding the molded article by injecting the molding oil into the sealed interior space (S130; see FIG. 11).

In addition, after expanding the workpiece (S130), the workpiece may be further separated from the mold means (S140), and setting a subsequent workpiece on the mold means (S150). .

In the step S110 of setting the workpiece in the mold means, the workpiece bent in a linear or constant shape is transferred and seated in a space between the lower mold and the upper mold through a transfer means such as a robot. Thereafter, the upper mold is lowered on the upper side of the lower mold, and the workpiece is set in engagement with a molding space formed between the lower mold and the upper mold.

Thereafter, to seal the open portion of the workpiece, the punch, which is a sealing means, is driven toward the open portion of the workpiece set in the mold means (S121), and when the punch contacts the open portion of the workpiece, the pressing force transmitted to the punch is applied. By sensing the measurement of the size and the set position of the workpiece (S122). The driving distance of the punch is adjusted according to the measurement of the size and the setting position of the workpiece (S123).

In addition, by detecting the driving force for driving the punch in the process of the punch is inserted into the open portion of the workpiece to determine the degree of insertion of the punch into the open portion of the workpiece, that is, the insertion distance (S124), thereby driving the punch The distance is adjusted (S125).

Here, the measurement of the size and the setting position of the workpiece is made in the contact sensor according to the embodiment of the present invention described above, and the degree to which the punch is inserted into the open portion of the workpiece is measured in the pressure sensor. In addition, the drive distance of the punch is adjusted by the control of the control means through the values sensed or measured by the contact sensor and the pressure sensor.

As such, even when the workpiece is deformed in the process of being set in the mold means or seated at an incorrect setting position, the open portion of the workpiece can be completely sealed.

As described above, according to the hydroforming mold apparatus and the hydroforming mold method using the same according to the present invention, it is possible to appropriately cope with the case in which the workpiece is finely deformed or not seated in the correct seating position in the mold during the automatic forming process. have. That is, by using a sensor means such as a contact sensor and a pressure sensor, the contact between the punch driven horizontally from the side of the mold and the workpiece seated in the mold is detected, and the internal pressure of the cylinder driving the punch to seal the workpiece. By detecting and judging, the open part of the workpiece can be completely sealed.

Therefore, in the process of hydroforming the workpiece, the occurrence of defective products such as crushing or bursting of a part can be prevented, thereby improving productivity of the hydroforming process.

In addition, by preventing the outflow of the molding oil and the like filled in the workpiece, it is possible to prevent damage or breakage of the hydroforming mold apparatus including the mold. Therefore, it is possible to reduce the management cost required for the maintenance and repair of the hydroforming mold apparatus, and the maintenance work caused by the outflow of the molding oil does not occur, thereby improving work efficiency.

As mentioned above, although this invention was demonstrated with reference to the above-mentioned Example and an accompanying drawing, this invention is not limited to this, It is limited by the following claims. Therefore, it will be apparent to those skilled in the art that the present invention may be variously modified and modified without departing from the technical spirit of the following claims.

1 is a block diagram of a hydroforming mold apparatus according to an embodiment of the present invention.

2 is a view showing a molding state using the hydroforming mold apparatus shown in FIG.

3 and 4 are views schematically showing the contact state of the punch detected in the hydroforming mold apparatus according to the present invention.

5 is a view schematically showing a closed state of the punch detected in the hydroforming mold apparatus according to the present invention.

6 and 7 is a flow chart showing a hydroforming mold method according to an embodiment of the present invention.

8 to 11 is a view showing a driving state of the hydroforming mold apparatus according to the flow chart shown in FIG.

Description of the Related Art [0002]

100: hydroforming mold apparatus 200: mold means

210: lower mold 220: upper mold

300: pressurization means 310: punch

320: pressurized cylinder 330: expansion bar connecting plate

340: extension bar 400: sensor means

410: contact sensor 420: pressure sensor

500 control means

Claims (8)

Mold means for providing a molding space for the workpiece; Pressurizing means for driving a punch to be inserted into an open portion of the workpiece set in the mold means, and injecting molding oil into an inner space of the workpiece sealed by the punch to expand and mold the workpiece; Sensor means for sensing a contact state of the punch with the workpiece and detecting a sealed state in which the punch is inserted into an open portion of the workpiece; And Control means for controlling the driving of the mold means and controlling the driving of the pressing means by comparing and determining the contact state and the closed state with a set reference contact state and a reference sealed state, respectively; Hydroforming mold apparatus comprising a. The method according to claim 1, A contact sensor which senses a contact of the punch with the workpiece and measures a driving distance of the punch entering the mold means; A pressure sensor for detecting a insertion distance of the punch by detecting a change in driving force for driving the punch when the punch is inserted into an open portion of the workpiece; Hydroforming mold apparatus comprising a. The method according to claim 1, The control means, The length and setting position of the workpiece to be seated on the mold means are determined by comparing the contact state with the reference contact state, and inserted into the open portion of the workpiece through comparison between the sealed state and the reference sealed state. Hydroforming die apparatus for controlling the driving of the pressing means by determining the insertion distance of the punch. The method according to any one of claims 1 to 3, The mold means, A lower mold fixedly installed on the ground and having a first forming groove for limiting deformation of the shape when expanding the workpiece and a first punch groove into which the punch is inserted; The punch is inserted in response to the first punching groove and the second molding groove which is driven up and down from the upper side of the lower mold and limits the deformation of the shape during expansion of the workpiece corresponding to the first molding groove. An upper mold having a second punch groove formed on a lower surface thereof; And A mold driving part which drives the upper mold up and down in response to a driving command of the control means; Hydroforming mold apparatus comprising a. The method according to claim 2, The pressing means, A pressurized cylinder for reciprocating driving the cylinder rod from the outside of the mold means toward the molding space, the driving force being measured by the pressure sensor provided at one side; An extension bar connecting plate connected to one end surface of the cylinder rod in engagement with the contact sensor and having a second flow path receiving the high pressure molding oil therethrough; And One end is coupled to the extension bar connecting plate in the extending longitudinal direction of the cylinder rod to horizontally support the punch coupled to the other end, and communicated with the second channel and the first channel formed to penetrate the punch. An expansion bar having a third flow passage formed along the longitudinal direction of the body; Hydroforming mold apparatus comprising a. Setting the workpiece to be expanded-molded in the mold means; Detecting the contact state and the sealing state of the punch to seal the open portion of the workpiece to correspond to the deformation of the workpiece and the change of the setting position, and control the driving of the punch compared to the set reference contact state and the reference sealing state, respectively Sealing the open portion of the workpiece through; And Injecting molding oil into the sealed inner space of the workpiece to expand the workpiece; Hydroforming mold method comprising a. The method according to claim 6, Sealing the open portion of the workpiece, Driving the punch toward an open portion of the workpiece set in the mold means; Measuring the size and setting position of the workpiece by sensing the pressing force transmitted to the punch when the open portion of the workpiece and the punch contact; Adjusting the driving distance of the punch according to the size and setting position of the workpiece; Detecting a driving force for driving the punch when the punch is inserted into an open portion of the workpiece to measure an insertion distance of the punch inserted into the open portion of the workpiece; And Adjusting the driving distance of the punch according to the insertion distance of the punch; Hydroforming mold method comprising a. The method according to claim 6 or 7, After expanding the workpiece, Separating the molded workpiece from the mold means; Setting subsequent workpieces in the mold means; Hydroforming mold method comprising a.

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