KR100945147B1 - A press system for hydro-forming - Google Patents

Abstract

The present invention allows the additional molding process by allowing the bellows type crash box having a large diameter portion and a small diameter portion to be expanded and simultaneously forming a bent portion between the large diameter portion and the small diameter portion in order to connect the vehicle bumper beam to the side member of the vehicle body. The present invention provides a hydroforming press apparatus for producing a bellows-type crash box molded article with a beautiful appearance without a need.

Hydroforming, Actual Feeder, Micro Radius, Crash Box, Bends, Bellows

Description

Hydroforming Press Unit {A PRESS SYSTEM FOR HYDRO-FORMING}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydroforming press apparatus, and more particularly, to forming a bellows type crash box having a large diameter portion and a small diameter portion in order to connect a vehicle bumper beam to a side member of a vehicle body and between the large diameter portion and the small diameter portion. The present invention relates to a hydroforming press apparatus for simultaneously forming a bent portion.

In general, a bumper in a vehicle absorbs an impact when a vehicle collides with another vehicle or a fixed body to promote the safety of the occupant, and at the same time a predetermined portion of the front and rear ends of the vehicle to minimize deformation of the vehicle body. The buffer unit is arranged.

As shown in FIG. 1, the bumper 100 has a stay 103 mounted on both rear sides of the bumper beam 101 disposed in the vehicle width direction from the front and the rear of the vehicle, and through the crash box 111. A bumper beam unit 105 fixed to the vehicle body side member 113, an energy absorber 107 disposed in front of the bumper beam 101 to absorb impact force, and the bumper beam 101 and an energy absorber ( And a bumper cover 109 that encloses 107.

Recently, in the development process for the safety and light weight of the bumper configured as described above, a crash box of various shapes is lightweight to minimize damage of the vehicle structure while absorbing impact energy during high speed (medium speed) collision. It is a trend that is formed of aluminum alloy and applied to large passenger cars.

FIG. 2 is a plan view of the bumper beam unit 105 to which the bellows type crash box 111 developed in view of the above is applied. The bellows type crash box 111 has a large diameter portion 201 and a small diameter portion 203 that are bent portions. It is formed integrally connected via 205, the tip of the small diameter portion 203 is welded to the stay 103, the tip of the large diameter portion 201 is connected to the flange 207 to side the bumper beam 101 It is attached to a member (not shown).

In order to produce such a bellows-type crash box 111, it is preferable that the diameter of the pipe formed with the large diameter portion 201 and the small diameter portion 203 is easily formed by the hydroforming method due to the expansion molding.

Briefly referring to the above-mentioned hydro-forming method, the hydroforming is performed at room temperature (10 ° C. to 30 ° C.), and in a special processing method of a machine sheet metal which expands and forms a pipe by using hydraulic pressure. For example, in the automobile industry, it is effective to reduce the weight and the molding cost of a press product made of a combination of large and small unit panels, such as front side members and bumpers.

Also in the pipe material applied to the above-described hydro-forming (HYDRO-FORMING), in order to reduce the weight, a high-strength aluminum alloy is often used in place of iron-based materials, in the case of such a high-strength aluminum alloy, formability at room temperature is iron-based Compared to the raw material, the moldability is ensured through softening treatment before forming, and hydraulic molding is performed step by step. After molding into a product, the rigidity is secured through reinforcement heat treatment.

The process of forming the tubular material having the large diameter portion 201 and the small diameter portion 203 through such hydroforming will be described with reference to FIGS. 3 to 6. First, as shown in FIG. 3, the hydroforming press is shown. Tube 300 is loaded on the lower mold 301 of the mold.

Subsequently, as shown in FIG. 4, in a state where the upper upper mold 303 is lowered, the hydraulic pressure supply devices 313 and 315 respectively disposed at both ends of the pipe 300 are mounted with the physical punches 305 and 307 mounted thereon. The physical punches 305 and 307 are advanced in the direction to seal the seals, and axial compressive pressure is applied to complete the molding of the mold and the mounting of the physical punches 305 and 307.

In this state, the pipe member 300, as shown in Figure 5, in the state fixed by the lower mold 301, the upper mold 303 and both of the physical punch (305, 307) of the physical punch (305, 307) Along with the accumulator, the hydraulic pressure is supplied to the inside of the pipe member 300 to expand the pipe member 300 along the forming surfaces 309 and 311 formed in the lower mold 301 and the upper mold 303, respectively. do.

As described above, the pipe member 300, in which the hydraulic molding is completed, is lifted from the lower mold 301 after the upper mold 303 is raised and the two physical punches 305 and 307 are removed, as shown in FIG. It becomes possible.

However, in the case of the bellows-type crash box 111, the large diameter portion 201 in the conventional hydroforming molding apparatus because the bent portion 205 forming an undercut should be formed between the large diameter portion 201 and the small diameter portion 203. ), After the expansion, the additional step is required to form the bent portion 205 by pressing at both ends by a separate press device, wherein the pressing force is not constant, cracking occurs in the bent portion 205, etc. There is a problem.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to expand the molding of the bellows type crash box having a large diameter portion and a small diameter portion and to connect the vehicle bumper beam to the side member of the vehicle body. By providing a bent portion between and the small diameter at the same time to provide a hydroforming press apparatus that can produce a bellows-type crash box molded article with a beautiful appearance without any additional process.

In the hydroforming press apparatus according to the present invention for achieving the object as described above in the hydroforming press apparatus for supplying the hydraulic pressure from the two hydraulic pressure supply device at both ends with respect to the pipe material regulated inside the mold, and expanding the pipe,

A lower mold which is fixedly installed on the lower bolster, and on both sides of an upper end thereof, an expansion mold forming surface of a pipe to be molded; An upper mold fixed to an upper slider corresponding to the lower mold, and having an extended mold formed on the lower surface thereof to form an expanded pipe molding surface of a pipe member to be molded corresponding to the expansion pipe molding surface of the lower mold; Two side lower bend forming steels respectively formed in the center between the two side expansion pipe forming surfaces on the lower mold and slidable in both directions, respectively, and having inclined cam surfaces on the outer sides of the corresponding cross sections; Two upper upper bending forming steels respectively formed in the center between the upper side of each of the expansion pipe forming surfaces so as to be slidable in both directions, and each having an inclined cam surface on the outside of the corresponding cross section; A lower cam steel installed at an inner center of the lower mold corresponding to each inclined cam surface of the lower bending molding steel; An upper cam steel installed at an inner center of the upper mold to correspond to each inclined cam surface of the upper bending molding steel; A lower cylinder mounted upwardly in the center of the bolster, the operation rod of which is connected to the lower cam steel through the center of the lower die; An upper cylinder mounted downward in the center of the slider and having an operating rod penetrating the center of the upper die and connected to the upper cam steel; An actual feeder mounted on each of the forward and backward operating rods of the both hydraulic pressure supply devices to fill the hydraulic pressure through both side ends of the pipe, and to integrally form a movable block for providing accumulating pressure at both ends of the pipe. Characterized in that.

Between the lower mold and both side lower bent steel and the upper mold and both the upper bent steel is characterized in that the restoring member for providing a restoring force to each of the lower lower bent steel and both upper bent steel.

The restoration member is preferably made of a coil spring.

The both side lower bending molding steel and both side upper bending molding steel are characterized in that the lower and upper symmetrical configuration on the upper mold, respectively.

The both side lower bent molding steel and the both side upper bent molding steel is characterized in that each outer end is formed of a round shaped bending end.

According to the hydroforming press apparatus according to the present invention as described above, in order to connect the vehicle bumper beam to the side member of the vehicle body, expansion of the bellows type crash box having a large diameter portion and a small diameter portion and between the large diameter portion and the small diameter portion By allowing the bent portion to be formed at the same time, there is an effect that a separate press pressurization process for forming the bent portion can be excluded.

Accordingly, there is an effect to produce a bellows type crash box molded article with a beautiful appearance at a time.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

7 is a cross-sectional side view of a hydroforming press apparatus according to an embodiment of the present invention, Figure 12 is a perspective view of a molded article produced by a hydroforming press apparatus according to an embodiment of the present invention.

Hydroforming press apparatus according to an embodiment of the present invention is to supply the hydraulic pressure from the two hydraulic pressure supply device (3,5) at both ends with respect to the tube material (1) supplied to the inside of the mold, the tube member (1) ) Is produced as a molded article (D) having a large diameter portion (D2) on both sides of the small diameter portion (D1) as shown in FIG.

The structure of this hydroforming press apparatus is provided with the lower die 11 and the upper die 13.

The lower mold 11 is fixedly installed on the lower bolster 15, and forms the expansion pipe forming surface (F) of the tube member 1 to be molded on both sides of the upper end.

The upper mold 13 is fixedly installed on the upper slider 17 in correspondence with the lower mold 11, and the lower end surface of the upper mold 13 to be molded corresponding to the expansion pipe forming surface F of the lower mold 11 (1). ) To form an expansion pipe forming surface (F).

In addition, both lower lower bending molds 21 are formed at the center between the two side expansion pipe forming surfaces F on the lower mold 11.

The lower side bend forming steel 21 is slidably installed in both directions with respect to the lower mold 11, and the lower side bend forming steel 21 respectively has an inclined cam surface CF on the outside of the corresponding cross section. Form.

In addition, at the center between the two side expansion pipe forming surface (F) on the upper die 13, both upper upper bending forming steel 23 is configured.

The upper two side bent steel 23 is slidably installed in both directions with respect to the upper die 13, respectively, the two upper upper bent steel 23 is the inclined cam surface (CF) on the outside of the corresponding cross-section respectively; Form.

Here, each of the lower lower bent molding steel 21 and the upper upper bent molding steel 23 is formed at each outer end of a round shaped bending end B.

In addition, as described above, both the lower bend forming steel 21 and the two upper bend forming steel 23 are configured to be symmetrical to the lower mold 11 and the upper mold 13, respectively.

The lower cam steel 25 is installed at the inner center of the lower mold 11 to correspond to the inclined cam surfaces CF of the lower bending molding steel 21.

In addition, the upper cam steel 27 is installed at the inner center of the upper die 13 corresponding to each inclined cam surface CF of the upper bent forming steel 23.

The lower cylinder 29 is mounted upward in the center of the bolster 15, and the actuating rod 31 of the lower cylinder 29 penetrates through the center of the lower mold 11 to lower the cam cam 25. Is connected to.

The upper cylinder 33 is mounted downward inside the center of the slider 17, and the operating rod 35 of the upper cylinder 33 penetrates through the center of the upper die 13 so as to pass the upper cam steel 27. Is connected to.

And the forward and backward actuating rods (7,9) of the two hydraulic pressure supply device (3,5) is equipped with an actual feeder (37,39) respectively to fill the hydraulic pressure through both ends of the pipe (1) and At the same time, it provides an accumulator.

In addition, the actual feeder (37, 39) of both sides is formed integrally with the movable block (41, 43) for providing the accumulating pressure at both ends of the tube (1).

That is, in the state in which the lower mold 11 and the upper mold 13 are joined together, the pipe member 1 therein is formed at both ends at both ends until the material is introduced by the amount of product formed to form the large diameter portion D2. Accumulation is provided by movable blocks 41 and 43 on the hydraulic pressure supply devices 3 and 5.

On the other hand, between the lower mold 11 and both side lower bent molding steel 21 and the upper mold 13 and the two upper upper bent molding steel 23, the lower lower bent molding steel 21 and both upper upper bent molding steel 23 Restoration members (S) for providing restoring force, respectively, are interposed therebetween.

Here, the restoring member (S) is preferably made of a coil spring.

Therefore, the operation of the hydroforming press apparatus of the present invention having the configuration as described above will be described in detail with reference to FIGS. 7 and 8 to 11.

First, the tube 1 is loaded onto the lower mold 11 of the hydroforming press apparatus, as shown in FIG.

Subsequently, as shown in FIG. 8, the upper mold 13 of the upper portion is lowered to be integrated with the lower mold 11, respectively.

In this state, as shown in Fig. 9, the two feeders (37, 39) of the two sides of the pipe as the forward and backward operating rods (7, 9) of the hydraulic pressure supply device (3, 5) is driven forward It is fitted on both ends of 1).

At this time, both movable blocks (41, 43) is to supply the accumulator in contact with both ends of the tube (1).

Subsequently, the hydraulic pressure supply apparatuses 3 and 5 on both sides are connected to each other through the physical feeders 37 and 39 on both sides together with the accumulator pressure through the two movable blocks 41 and 43, as shown in FIG. By supplying a hydraulic pressure inside the tube), both sides of the pipe member 1 are expanded.

As described above, when the pipe member 1 is expanded in the large diameter portion D2 by the accumulation of pressure and hydraulic pressure, the upper cylinder 33 and the lower cylinder 29 are driven forward at the same time as shown in FIG. The steel 27 and the lower cam steel 25 is pushed.

Then, both the upper upper bending steel 23 and the lower lower bending steel 21 are cam-operated by the upper cam steel 27 and the lower cast steel 25 to slide in both directions.

Accordingly, each of the bent ends B of the upper and lower bending steel 23 and the lower lower bending steel 21 on both sides is formed in a stepped surface between the small diameter portion D1 and the large diameter portion D2 of the pipe 1. By pressing and bending the side, the molded article D as shown in Fig. 12 is produced.

Of course, only the pressure is provided during the operation of the two upper bent steel (23) and the two lower bent steel (21), the hydraulic pressure is kept in a blocked state.

Accordingly, by the hydroforming press apparatus according to the present embodiment, as shown in FIG. 12, the molded product D in which the large diameter portion D2 is integrally molded together with the bent portion BP on both sides of the small diameter portion D1. 2 is used by cutting along the center cutting line CL of the small diameter portion D1 in the machining process in order to apply to the vehicle crash box as shown in FIG.

1 is an exploded perspective view of a general vehicle bumper.

2 is a plan view of a bumper beam unit for a vehicle to which a bellows type crash box is applied.

3 to 6 is a step-by-step operational state diagram of the hydroforming press apparatus according to the prior art.

7 is a sectional side view of the hydroforming press apparatus according to the embodiment of the present invention.

8 to 11 is a step-by-step operating state diagram of the hydroforming press apparatus according to an embodiment of the present invention.

12 is a perspective view of a molded product produced by the hydroforming press apparatus according to the embodiment of the present invention.

Claims (5)

In the hydroforming press apparatus for supplying the hydraulic pressure from the two hydraulic pressure supply device at both ends thereof with respect to the pipe material supplied to the inside of the die, A lower mold which is fixedly installed on the lower bolster, and on both sides of an upper end thereof, an expansion mold forming surface of a pipe to be molded; An upper mold fixed to an upper slider corresponding to the lower mold, and having an extended mold formed on the lower surface thereof to form an expanded pipe molding surface of a pipe member to be molded corresponding to the expansion pipe molding surface of the lower mold; Two side lower bend forming steels respectively formed in the center between the two side expansion pipe forming surfaces on the lower mold and slidable in both directions, respectively, and having inclined cam surfaces on the outer sides of the corresponding cross sections; Two upper upper bending forming steels respectively formed in the center between the upper side of each of the expansion pipe forming surfaces so as to be slidable in both directions, and each having an inclined cam surface on the outside of the corresponding cross section; A lower cam steel installed at an inner center of the lower mold corresponding to each inclined cam surface of the lower bending molding steel; An upper cam steel installed at an inner center of the upper mold to correspond to each inclined cam surface of the upper bending molding steel; A lower cylinder mounted upwardly in the center of the bolster, the operation rod of which is connected to the lower cam steel through the center of the lower die; An upper cylinder mounted downward in the center of the slider and having an operating rod penetrating the center of the upper die and connected to the upper cam steel; An actual feeder mounted on each of the forward and backward operating rods of the both hydraulic pressure supply devices to fill the hydraulic pressure through both side ends of the pipe, and to integrally form a movable block for providing accumulating pressure at both ends of the pipe. Hydroforming press apparatus, characterized in that. The method of claim 1, And a restoring member between the lower mold and both lower lower bending steel, and the upper mold and both upper upper bending steel, respectively, a restoring member for providing restoring force to both lower lower bending steel and both upper upper bending steel. The method of claim 2, The restoration member Hydroforming press apparatus comprising a coil spring. The method of claim 1, The lower side of the bend forming steel and the upper side of the bending bent steel Hydroforming press apparatus, characterized in that the lower mold and the upper mold are configured symmetrically. The method of claim 1, The lower side of the bend forming steel and the upper side of the bending bent steel A hydroforming press apparatus, wherein each outer end is formed of a round shape bending end.

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