JP3166550B2 - Method for shaping sheet for skin and apparatus for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin sheet shaping method for shaping a skin sheet into a predetermined shape and an apparatus for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a stamping molding method capable of supplying a molten resin at a low pressure has been known as a method for molding an interior member for a vehicle in which a hard resin base is laminated on a skin sheet. FIG. 11 shows a resin molding apparatus 200 for performing the stamping molding method. In the stamping molding method, the female mold 202 and the core mold 204 are temporarily tightened while the skin sheet H is set on the female mold 202, and the female mold 20 is formed.
The molten resin R is supplied to the gap between the skin sheet H set to 2 and the core mold 204, and the female mold 202 and the core mold 204 are supplied.
This is a method of molding a resin molded product while pressing the molten resin R by clamping the mold.

In this resin molding apparatus 200, a skin sheet H is set on a female mold 202 and a skin sheet H
A clamp mechanism 210 is provided on the side of the core mold 204 in order to apply tension to the core. The clamp mechanism 210 includes a support member 212 that passes through the through hole 204a of the core mold 204.
And a skin presser 2 fixed to the distal end of the support member 212.
14 and a pin 21 protruding from the surface of the
6 and a spring 218 provided between the core mold 204 and the skin holder 214.

In this clamp mechanism 210, the female mold 20
2 is temporarily fastened to the core mold 204, the support member 212 clamps the skin sheet H together with the end surface of the female mold 202, and the pins 216 pierce the skin sheet H to stop the skin sheet H. . Then, at the time of the mold clamping, the skin sheet H is stopped by the pins 216 and extended in a state where tension is applied, so that the concave portion 20 of the female mold 202 is formed.
It is shaped according to the shape of 2a.

[0005]

However, as shown in FIG. 12, since both end portions Hr of the skin sheet H are fixed by the pins 216, as shown in FIG. Torn. Both ends H of this torn skin sheet H
As for r, an area indicated by a wavy line is cut and discarded so as not to appear in the product. Both ends Hr discarded in this way
Is 50% of the area of the skin sheet H for some products.
%, And the yield is not good.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and improves the yield of a skin sheet without damaging the edges of the skin sheet when shaping the skin sheet into a predetermined shape. An object of the present invention is to provide a method for shaping a sheet for a skin and a manufacturing apparatus therefor.

[0007]

Means for Solving the Problems In order to solve the above-mentioned problems, the invention of claim 1 is to form a skin sheet having a design surface and a back surface opposite to the design surface into a predetermined shape. A method for shaping a skin sheet, comprising: a forming surface for shaping the skin sheet into a predetermined shape; a forming die for imitating the skin sheet on the forming surface; and a design surface side of the skin sheet. Clamping means having a first holding part and a second holding part for holding the back side, clamping means for sandwiching the skin sheet between the first holding part and the second holding part, and a skin provided on the second holding part, And a rough surface portion for applying a frictional force greater than that of the first pressing portion in a direction in which the sheet for use is extended, and using the device having the rough surface portion to clamp the skin sheet between the first and second pressing portions of the clamping means. Process and molding of the skin sheet and the mold held by the clamping means And a step of shaping the skin sheet between the first and second pressing portions of the clamping means and shaping it into a predetermined shape according to the molding surface of the molding die. And the following.

[0008] A second aspect of the present invention is a skin sheet shaping apparatus for shaping a skin sheet having a design surface and a back surface opposite to the design surface into a predetermined shape, wherein the skin sheet is formed into a predetermined shape. A molding die having a molding surface to be shaped and imitating a skin sheet on the molding surface; a first pressing portion for pressing a design surface side of the skin sheet and a second pressing portion for pressing a back surface side; A clamping means for clamping the skin sheet between the first and second pressing portions, and a moving means for moving the skin sheet and the molding surface of the mold held by the clamping means in a direction in which they are in close contact with each other; Wherein the second pressing portion of the clamping means has a rough surface portion that applies a greater frictional force than the first pressing portion in the direction in which the skin sheet is extended.

[0009]

In the method according to the first aspect, the first of the clamping means is provided.
The skin sheet is sandwiched by the holding portion and the second holding portion, and then the skin sheet sandwiched by the clamp means and the molding surface of the mold are moved in a direction in which they are in close contact with each other, and the skin sheet is brought into contact with the molding surface. It is shaped into a predetermined shape by imitating. At this time, the skin sheet is slid and shaped by applying tension to the skin sheet by the first and second pressing portions of the clamping means. The rough surface portion of the second pressing portion applies a greater frictional force to the back surface side of the skin sheet than the design surface side pressed by the first pressing portion. Since the scratch does not extend to the design side, the product is not damaged.

Therefore, it is not necessary to use a large skin sheet in consideration of a portion to be discarded due to a scratch generated when the skin sheet is clamped, and the yield of the skin sheet can be improved.

A second aspect of the present invention is an apparatus for suitably implementing the invention according to the first aspect.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the structure and operation of the present invention described above, preferred embodiments of the present invention will be described below.

FIG. 1 shows a vehicle interior member 10 manufactured by using a method for shaping a skin sheet according to an embodiment of the present invention. The vehicle interior member 10 is formed by laminating a skin 12 and a hard resin base 13. The outer skin 12 has a design surface 12a on the front side and a back surface 12a on the resin base 13 side.
b. The skin 12 and the resin base 13 are both formed of polypropylene (PP). The skin 12 may be formed by laminating a hard skin layer having a textured pattern on the design surface 12a side and a foam layer.

Next, a stamping molding process for manufacturing the vehicle interior member 10 will be described. The stamping molding step is performed by laminating a molten resin on a skin sheet forming the skin 12 using a resin molding apparatus 40 shown in FIG. 2 to form a resin base.

First, the configuration of the resin molding apparatus 40 will be described. The resin molding device 40 includes a female mold 42 and a core mold 44 that are arranged to face each other in the horizontal direction. The female mold 42 is clamped by being driven toward the core mold 44 by a female drive device 46.

The core mold 44 is provided with an injection molding device 50.
A resin introduction passage 54 communicating with the nozzle 52a is formed. The injection molding device 50 injects a molten resin by rotating and moving a screw. In addition, a shut-off rod 57 that opens and closes the injection port 54 a by being driven forward and backward by a shut-off driving device 56 is inserted through the resin introduction path 54.

Further, the core mold 44 includes the skin sheet 1.
A clamp mechanism 60 is provided for holding down 2A (FIG. 4) and applying tension. This clamping mechanism 60
As shown in FIG. 4, the support member 62 includes a support member 62 that penetrates the through hole 61 of the core mold 44 and has a stop portion 62a, a skin press portion 63 that presses the skin sheet 12A, and a spring 64. The skin pressing portion 63 includes a first pressing portion 63a, which is an end of the core mold 44, and a second pressing portion 63b provided at a distal end portion of the support member 62.

FIG. 3 is a plan view showing a second pressing portion 63b constituting the skin pressing portion 63. A rough surface portion 63c is fixed to a part of the surface of the second pressing portion 63b by screwing or the like. The rough surface portion 63c is a plate material having a predetermined thickness, and has on its surface a large number of quadrangular pyramid projections formed by etching or discharge processing with nitric acid, and the roughness value is # 2.
0 to # 40. The value of the roughness is #
If it is 20 or less, the skin sheet 12A is broken, or the back surface of the skin sheet 12A is shaved to cause clogging of the rough surface portion 63c and maintenance becomes troublesome. On the other hand, if it is # 60 or more, the skin sheet 12A This range is preferable because the force for suppressing the pressure becomes weak.

Next, a series of steps using the resin molding apparatus 40 will be described with reference to FIG. 1 and FIGS. First, the skin sheet 12 is placed on the female mold 42 shown in FIG.
A is set, and then a drive signal is output to the female drive device 46 to move the female die 42 rightward in the figure. Thus, the skin sheet 12A is pressed by the skin pressing portion 63 of the clamp mechanism 60 at its end 12Ar (FIG. 4).

Further, when the female mold 42 moves in the direction of the core mold 44, the skin sheet 12A is pushed by the core 44a of the core mold 44, but the skin sheet 12A is held by the clamp mechanism 60. The concave portion 42a of the female mold 42 is positioned while being tensioned.
And the female mold 42 and the core mold 44 are temporarily tightened as shown in FIG.

In a subsequent step, the molten resin is injected from the injection molding apparatus 50, and the molten resin is injected into the resin introduction path 54 from the nozzle 52a. Then, by the drive of the shut-off driving device 56, the shut-off rod 57 moves in the direction of arrow d2 as shown in FIG.
Opens. When the injection port 54a is opened, the injection molding device 50
Is injected from the resin introduction path 54 toward the back surface 12Ab of the skin sheet 12A. Thereby, the molten resin R is applied to the skin sheet 1.
2A is extended and pushed into the recess 42a side of the female mold 42.

Subsequently, the shut-off rod 57 moves in the direction of arrow d3 by the shut-off driving device 56 to perform a shut-off operation for closing the injection port 54a. By this shut-off operation, the skin sheet 12A
The molten resin R on the back surface 12Ab side is cut off from the resin introduction path 54.

In the subsequent step, as shown in FIG. 7, the female mold 42 is further moved with respect to the core mold 44 to perform mold clamping. By this mold clamping, the molten resin R on the back surface 12Ab side of the skin sheet 12A spreads over the entire back surface 12Ab side of the skin sheet 12A. At this time, the skin sheet 12A is extended and shaped according to the recess 42a of the female mold 42.

While maintaining the mold clamping state, cooling for curing the molten resin is performed, and the back surface 12Ab of the skin sheet 12A is integrated with the molten resin R. Subsequently, a drive signal is output to the female-type driving device 46 to move the female type 42 from the mold-clamping completion position shown in FIG. 7 to the origin position (the state of FIG. 2), and the molded product is released. . Then, the vehicle interior member 10 shown in FIG. 1 is completed by performing an end surface treatment of the skin sheet 12A and the like.

In such a series of steps, the skin sheet 12A held by the clamp mechanism 60 is
While a large tension is applied to the rough surface portion 63c of the pressing portion 63b, it is extended by the heat and pressure of the molten resin R and shaped into a shape following the concave portion 42a of the female mold 42.
At this time, as shown in FIG. 8, the rough surface portion 63c of the second pressing portion 63b damages the portion 12Ad of the back surface 12Ab of the skin sheet 12A, but does not reach the front surface 12Aa side. Back surface 12Ab of wounded skin sheet 12A
Portion 12Ad is wound around the molten resin R and welded to the resin base 13.

Therefore, when the skin sheet 12A is clamped by the clamp mechanism 60, the skin sheet 12A
Since the surface 12Aa side of A is not scratched, it is not necessary to use the large skin sheet 12A in consideration of the portion to be discarded, and the yield of the skin sheet 12A can be improved.

9 and 10 are views showing a vacuum forming method according to another embodiment. FIG. 9 shows a heating step, and FIG. 10 shows a vacuum forming step.

The heating step is performed using a heating device 100. The heating device 100 includes an upper heater 103 and a lower heater 105, and has a heating chamber 107 between them. In this heating step, the entire periphery of the skin sheet 111A is held by the clamp mechanism 114. The clamp mechanism 114 includes a first holding portion 115 and a second holding portion 116, and sandwiches the skin sheet 111 </ b> A therebetween, moves the sheet 111 </ b> A to the heating chamber 107 of the heating device 100, and moves the upper heater 103 and the lower Skin sheet 11 by heater 105
Heat the upper and lower surfaces of 1A, respectively.

Here, as the skin sheet 111A,
Any thermoplastic material can be used, and for example, polypropylene, polyvinyl chloride, or the like can be used.
The heating temperature at this time should just be the temperature which softens thermoplastics, for example, is 140 to 200 degreeC.

On the upper surface side of the second pressing portion 116, a rough surface portion 116a is provided. This rough surface portion 116a
Are formed from a large number of quadrangular pyramid protrusions similar to FIG.

The vacuum forming step is performed by the vacuum forming apparatus 1 shown in FIG.
21. The vacuum forming apparatus 121 includes
3 is provided on the fixing frame 127. On the upper portion of the fixing frame 127, a fixing portion 129 for fixing the first pressing portion 115 and the second pressing portion 116 sandwiching the skin sheet 111A is provided. Is formed. A convex forming die 133 having a forming surface 131 is fixed in the fixed frame 127. Since the molding die 133 is made of porous ceramic, the pores thereof allow air to pass therethrough. Molding surface 13 of such a porous molding die 133
In FIG. 1, pore openings formed substantially uniformly dispersed are formed. The molding die 133 is formed, for example, by sintering a material obtained by mixing ceramic powder with metal powder.

The lower part inside the fixed frame 127 is a lower pressure chamber 137 surrounded by the fixed frame 127, the molding die 133 and the bottom plate 123. The lower pressure chamber 137 has a vent 139 formed in the center of the bottom plate 123.
, A vacuum pump (not shown) is connected.

In this vacuum forming step, first, the first pressing portion 115 holding the heated skin sheet 111A is held.
Then, the second pressing portion 116 is fixed to the fixing portion 129. As a result, the skin sheet 111A is heated and softened, and thus slightly extended. From this state, the vacuum pump is driven to evacuate. This allows
The skin sheet 111 </ b> A is sucked through the porous mold 133, and is shaped in close contact with the molding surface 131 of the mold 133. Then, the product is completed by moving the skin sheet 111A held by the clamp mechanism 114 and removing the skin sheet 111A.

According to the above-described embodiment, the rough surface portion 116a of the second pressing portion 116 is shaped by sliding the skin sheet 111A while applying a large tension, but the rough surface portion 116a may damage the skin sheet 111A. Even if it is applied, the scratch is on the surface 1
Since it does not reach the 11Aa side, the product is not damaged.
Therefore, similarly to the first embodiment, it is not necessary to use the large skin sheet 111A in consideration of the portion to be damaged, and the yield of the skin sheet 111A can be improved.

The present invention is not limited to the above-described embodiment, but can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

The first holding portion constituting the clamp mechanism may be formed integrally with the peripheral edge of the core type, or may be formed by using another mechanism.

[0037]

As described above, according to the first aspect of the present invention,
According to the method for shaping a skin sheet according to the above, the back surface side of the skin sheet is pressed by the rough surface portion of the clamping means, so that no damage is caused on the design surface side, so that a large skin sheet in anticipation of discarding that portion Need not be used, and the yield of the skin sheet can be improved.

According to the sheet forming apparatus for a skin according to the second aspect, the invention according to the first aspect can be suitably realized.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a part of a vehicle interior member manufactured by a method of shaping a skin sheet according to one embodiment of the present invention.

FIG. 2 is a schematic view showing a resin molding apparatus.

FIG. 3 is an explanatory view for explaining a skin pressing portion of the clamp mechanism.

FIG. 4 is an explanatory view illustrating a stamping molding method using a resin molding apparatus.

FIG. 5 is an explanatory view illustrating a step following FIG. 4;

FIG. 6 is an explanatory view illustrating a step following the step shown in FIG. 5;

FIG. 7 is an explanatory view illustrating a step following FIG. 6;

FIG. 8 is an explanatory diagram for explaining the operation of the clamp mechanism.

FIG. 9 is an explanatory view illustrating a heating step of a skin sheet according to another embodiment.

FIG. 10 is an explanatory view illustrating a vacuum forming method according to another embodiment.

FIG. 11 is an explanatory view illustrating a conventional stamping molding step.

FIG. 12 is an explanatory view illustrating a state in which a conventional skin sheet is pressed.

FIG. 13 is an explanatory view illustrating a state after the skin sheet is shaped.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Interior member for vehicles 12 ... Skin 12a ... Design surface 12b ... Back surface 12A ... Skin sheet 12Aa ... Surface 12Ab ... Back surface 12Ar ... End 13 ... Resin base 40 ... Resin molding device 42 ... Female type 42a ... Concave 44 ... Core type 44a Core part 46 Female drive device 50 Injection molding device 52a Nozzle 54 Resin introduction path 54a Injection port 56 Shut-off drive device 57 Shut-off rod 60 Clamp mechanism 61 Through-hole 62 Supporting member 62a Stop part 63 Skin holding part 63a First holding part 63b Second holding part 63c Rough surface part 64 Spring 100 Heating device 103 Upper heater 105 Lower heater 107 Heating chamber 111A Skin Sheet 111Aa: Front surface 114: Clamp mechanism 115: First pressing portion 116: Second pressing portion 116a: Rough surface 121 ... vacuum forming apparatus 123 ... bottom plate 127 ... fixed frame 129 ... fixing portion 131 ... forming surface 133 ... mold 137 ... lower pressure chamber 139 ... vent hole H ... epidermal sheet Hr ... end R ... molten resin

Continuation of front page (56) References JP-A-6-126773 (JP, A) JP-A-6-55570 (JP, A) JP-A-1-195011 (JP, A) JP-A-5-64825 (JP) JP-A-8-15623 (JP, A) JP-A-8-142127 (JP, A) JP-A-7-164481 (JP, A) JP-A-7-276426 (JP, A) 61-14922 (JP, A) JP-A-5-169486 (JP, A) JP-A-5-293896 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 45/00 -45/84 B29C 43/00-43/58 B29C 51/00-51/46

Claims (2)

(57) [Claims] 1. A skin sheet shaping method for shaping a skin sheet having a design surface and a back surface opposite to the design surface into a predetermined shape, wherein the skin sheet is shaped into a predetermined shape. A molding die having a surface and imitating a skin sheet on the molding surface; a first pressing portion for pressing a design surface side of the skin sheet and a second pressing portion for pressing a back surface side; Clamp means for clamping the skin sheet between the portion and the second holding portion; and a rough surface portion provided on the second holding portion and applying a larger frictional force than the first holding portion in a direction in which the skin sheet is extended. A step of clamping the skin sheet between the first and second holding portions of the clamping means by using an apparatus having: The step of moving in the direction to make close contact, Beauty skin sheet shaping method characterized in that by modeled after molding surface of the mold while sliding the skin sheet and a step of shaping to a predetermined shape between the second pressing portion. 2. A skin sheet shaping apparatus for shaping a skin sheet having a design surface and a back surface opposite to the design surface into a predetermined shape, wherein the skin sheet is shaped into a predetermined shape. A molding die having a surface and imitating a skin sheet on the molding surface; a first pressing portion for pressing a design surface side of the skin sheet and a second pressing portion for pressing a back surface side; Clamping means for holding the skin sheet between the second pressing portion, and moving means for moving the skin sheet held by the clamping means and the molding surface of the molding die in a direction in which they are in close contact with each other; The second holding portion of the clamping means has a roughened surface portion that applies a larger frictional force than the first holding portion in the direction in which the skin sheet is extended.