Apparatus for molding a crash pad for a vehicle

Provided is an apparatus for molding a crash pad for a vehicle, which includes a first metal mold in which an insert cavity is formed, a second metal mold installed opposite the first metal mold, an insert inserted into the insert cavity and having a through-hole toward the first metal mold so as to define a boundary between an upper part and a lower part of the crash pad that is injection-molded by the first and second metal molds, and a resin introducing unit installed in the first metal mold abutting on the insert and having an elastically adjusted space into which molding resin is introduced through the through-hole when an injection pressure exceeds a predetermined level.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority of Korean Patent Application Number 10-2011-0133137 filed Dec. 12, 2011, the entire contents of which application is incorporated herein for all purposes by this reference.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates, in general, to an apparatus for molding a crash pad for a vehicle, capable of preventing molding resin from overflowing at a predetermined injection pressure of the molding resin, and increasing a supporting area of an insert to stably support the insert.

2. Description of Related Art

Generally, a crash pad called an instrument panel pad or a dashboard is installed in the front of the interior of a vehicle in which a steering wheel and instruments are located.

This crash pad is an important in-built part installed to provide a variety of pieces of information required for driving and driving convenience, and is manufactured by injection molding of injecting a kind of synthetic resin into an injection mold.

However, the crash pad has recently developed a design tendency to impart a two-tone color for luxurious feeling. A convention method for this two-tone color will be described with reference toFIGS. 1A and 1B.

Such a crash pad1is made up of an upper panel2and a lower panel3. The upper and lower panels2and3are each formed by injection molding. Surfaces of the upper and lower panels2and3are painted so as to have different colors. The upper and lower panels2and3are assembled using clips4or the like, so that the crash pad1having a two-tone color is manufactured.

Meanwhile, as for another related art for manufacturing such a two-tone color crash pad, as shown inFIGS. 2A and 2B, a crash pad1is formed integrally by injection molding, one of upper and lower sides is masked, and then the other side is painted, so that a two-tone color crash pad is completed.

However, these related arts are essential to carry out painting, assembling, and masking in order to realize the two-tone color. Thus, these processes require considerable costs and materials, so that the production cost and weight of the crash pad are increased.

For this reason, a method of incorporating the two-tone color into the crash pad without the masking process or the assembling process has been studied. Referring toFIG. 3, an insert11is mounted in the cavity of an injection metal mold10so as to impart bonding strength while forming a boundary of the two-tone color. Upper and lower fill spaces12and13are formed on upper and lower portions of the insert11, and are filled with different color resins for the injection molding.

Here, to support the insert11inside the injection metal mold10, the insert11is provided with a groove11a, and the injection metal mold is provided with a projection10aon an inner face thereof which faces the groove11a.

However, in this related art, the insert is not stably mounted and supported in the injection metal mold, and thus a separate fixing device is required to fix the insert.

Further, when an excessive injection pressure is applied to the resin filled in the upper and lower fill spaces, the insert is deformed by the excessive injection pressure as shown inFIG. 4, and thus the molding resin is filled beyond the boundary, which is called an overflow phenomenon.

In contrast, when an insufficient injection pressure is applied to the resin filled in the upper and lower fill spaces, the boundary becomes thin as shown inFIG. 5, so that poor molding is caused by short fill of the resin.

SUMMARY OF INVENTION

Various aspects of the present invention provide for an apparatus for molding a crash pad for a vehicle, capable of preventing molding resin from overflowing into a boundary part in the event of an excessive injection pressure of the molding resin.

Various aspects of the present invention provide for an apparatus for molding a crash pad for a vehicle, capable of increasing a supporting area of an insert installed in an injection metal mold to stably support the insert without a separate device.

Various aspects of the present invention provide for an apparatus for molding a crash pad for a vehicle, which includes a first metal mold in which an inert cavity is formed, a second metal mold installed opposite the first metal mold, an insert inserted into the insert cavity and having a through-hole toward the first metal mold so as to define a boundary between an upper part and a lower part of the crash pad that is injection-molded by the first and second metal molds, and a resin introducing means installed in the first metal mold abutting on the insert and having an elastically adjusted space into which molding resin is introduced through the through-hole when an injection pressure exceeds a predetermined level.

Here, the resin introducing means may include a core hole that is formed in the first metal mold and is spatially interconnected with the through-hole, a core which is air-tightly installed in the core hole, which receives the injection pressure from one end thereof, and which is pushed in the core hole by the pressure of the molding resin introduced through the through-hole when the applied injection pressure exceeds a predetermined level, and a spring that is provided to the other end of the core and that applies an elastic force to the core.

Further, the core may include a flange formed on the other end thereof, and a stepped stopper may be formed at one end of the core hole so as to allow the flange to be caught by the stepped stopper, so that the insert can be placed and supported on one end of the core.

Also, the insert may include a boundary part formed at a portion where the crash pad is divided into the upper and lower parts, a rein introducing part formed on one side of the boundary part and having the through-hole in a middle thereof through which the molding resin passes, and a support part which is formed on the other side of the boundary part, whose longitudinal length is greater than that of the rein introducing part, and which is inserted into the insert cavity.

Here, the boundary part may include a boundary recess in an outer face thereof, and the second metal mold may include a boundary projection so as to be inserted into and placed in the boundary recess. The boundary recess may be formed to such a minimum depth that the boundary projection is able to be inserted.

Further, the support part may include a support projection at one end thereof, and the support projection may be closely supported on an inner face of the insert cavity, so that the molding resin can be injected on one side of the support part.

According to the present invention, when the injection pressure exceeds a predetermined level, the core moves to form a space into which molding resin is introduced. As such, the insert is not deformed, and the molding resin does not overflow. As a result, poor molding of the crash pad is prevented.

Moreover, since a supporting area of the support part formed on the insert is wide, the insert can be more stably supported in the first metal mold, and the insert can be easily placed and supported in the first metal mold.

In addition, since portions of the upper and lower parts which are adjacent to the insert are molded so as to be thick, it is possible to prevent the upper and lower parts from being molded imperfectly although the injection pressure is somewhat insufficient.

DETAILED DESCRIPTION

As shown inFIGS. 6 to 8, an apparatus for molding a crash pad for a vehicle includes a first metal mold100having an insert cavity110formed therein, a second metal mold200installed opposite the first metal mold100, an insert300inserted into the insert cavity110and having a through-hole325toward the first metal mold100so as to define a boundary between an upper part50and a lower part60of a crash pad that is injection-molded by the first and second metal molds100and200, and a resin introducing means installed in the first metal mold100abutting on the insert300and having an elastically adjusted space into which molding resin can be introduced through the through-hole325when an injection pressure exceeds a predetermined level.

The insert300is provided between the first metal mold100and the second metal mold200, and serves as a partition between the upper part50and the lower part60. The upper and lower parts50and60are filled with the molding resins having different colors, so that a crash pad having a two-tone color is molded.

Here, when the injection pressure of the molding resin becomes higher than a predetermined level, the molding resin is pushed toward the first metal mold100via the through-hole325formed in the insert300, thereby preventing deformation of the insert300and the resultant overflow phenomenon of the molding resin.

The resin introducing means includes a core hole120that is formed in the first metal mold100and that is spatially interconnected with the through-hole325, a core400which is air-tightly installed in the core hole120, which receives the injection pressure from one end thereof, and which is pushed in the core hole120by the pressure of the molding resin introduced through the through-hole325when the applied injection pressure exceeds a predetermined level, and a spring410that is provided to the other end of the core400and that applies an elastic force to the core400.

In detail, when the injection pressure of the molding resin injected into the lower part60exceeds a predetermined level, the molding resin pushes the core400via the through-hole325, and thus the core400moves in the core hole120while the spring410is being compressed, so that the molding resin is injected into the core hole120in which the core400moves. Thus, the molding resin is prevented from overflowing due to the excessive pressure of the molding resin, and thus it is possible to prevent poor molding of the crash pad.

Further, the lower part60as well as the upper part50is molded to a sufficient thickness. Although the injection pressure is insufficient, it is possible to prevent the upper and lower parts50and60from being molded imperfectly.

One end of the core400is placed and supported on one face of the insert300, so that it is possible to more stably support the insert300.

In the present invention, the other end of the core400is provided with a flange420. A stepped stopper130is formed at one end of the core hole120so as to allow the flange420to be caught by the stepped stopper130. As a result, the insert300can be placed and supported on one end of the core400.

That is, in a state where the core400is inserted into the core hole120, the flange420formed on the core400is caught by the stepped stopper130, so that the core400supports the insert300and applies no push force to the insert300. Thus, the insert300can be reliably supported.

In the present invention, the insert300includes a boundary part310formed at a portion where the crash pad is divided into the upper and lower parts50and60, a rein introducing part320formed on one side of the boundary part310and having the through-hole325in the middle thereof through which the molding resin passes, and a support part330which is formed on the other side of the boundary part310, whose longitudinal length h1is greater than that h2of the rein introducing part320, and which is inserted into the insert cavity110. In various embodiments the length h1may be at least twice the length h2.

That is, the support part330is deeply inserted into and supported in the first metal mold100. Thereby, an area where the insert300is supported in the first metal mold100is further widened. Thus, it is possible to stably support the insert300without realizing a separate coupling device.

At this time, the insert cavity110into which the support part330is inserted must be formed in a shape corresponding to that of the support part330.

In the present invention, a boundary recess315is formed in an outer face of the boundary part310, and a boundary projection210is formed on the second metal mold200so as to be inserted into and placed in the boundary recess315. The boundary recess315may be formed to such a minimum depth d that the boundary projection210can be inserted.

For example, the depth d of the boundary recess315may be about 1 mm, and the boundary projection210is inserted into and placed in the boundary recess315. Thus, the insert300is exposed to the outside in the crash pad to a minimum extent, so that the crash pad is allowed to have a luxurious geometry.

In the present invention, the support part330is provided with a support projection335at one end thereof. The support projection335is closely supported on an inner face of the insert cavity110. The molding resin may be injected on one side of the support part330.

That is, an end of the support part330is inserted into the insert cavity110, thereby enhancing a supporting force of the insert300. Further, the upper part50is molded on one side of the support part330, so that the insert300and the upper part50can be molded with a firm bonding force.

Operation and effects of the present invention will be described in detail with reference toFIGS. 6 and 7.

When molding resins having difference colors are injected through gates formed in the metal mold, the upper part50and the lower part60are molded in different colors by the insert300inserted into the metal mold.

In the initial stage of the injection molding, the injection molding proceeds in a state where the core400stably supports the insert300due to an elastic force of the spring410. When an injection pressure is raised above a predetermined level, the molding resin passes through the through-hole325to press the core400.

Then, the spring410is compressed because the spring410does not withstand the injection pressure of the molding resin, and thus the core400moves toward the spring410. As a result, the molding resin is introduced into the core hole120in which the core400moves.

Accordingly, even when the injection pressure is excessively applied by the molding resin, a space into which the molding resin is introduced is formed by the movement of the core400. Thereby, the insert300is prevented from being deformed, and thus the molding resin is prevented from overflowing into the boundary part310. Thus, it is possible to prevent poor molding of the crash pad.

Further, since a supporting area of the support part330formed on the insert300is very wide, the insert300can be stably supported in the first metal mold100without a separate device, and a process of placing the insert300into the first metal mold100can also be simply carried out by a robot.

In addition, since portions of the upper and lower parts50and60which are adjacent to the insert300are molded so as to be thick, it is possible to prevent the upper and lower parts50and60from being molded imperfectly, although the injection pressure is insufficient. In this way, the cross section of the crash pad is reinforced, and simultaneously head impact deceleration can be maintained below a target value.

For convenience in explanation and accurate definition in the appended claims, the terms upper or lower, front or rear, inside or outside, and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.