JP3536334B2 - Resin extrusion molding equipment for resin molded products whose cross-sectional shape changes - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for extruding a resin molded article whose sectional shape changes. 2. Description of the Related Art Japanese Patent Laid-Open Publication No. Hei.
An apparatus for cutting into an arbitrary cross-sectional shape by a cutter after resin extrusion molding as disclosed in Japanese Patent Application Laid-Open No. 244836 or resin extrusion as disclosed in Japanese Patent Application Laid-Open No. 3-143730. 2. Description of the Related Art There is known an apparatus (second conventional technique) in which a movable shutter is provided in a mouth to change the cross-sectional shape by stopping the flow of extruded resin. [0003] In the first prior art described above, the resin is processed into an arbitrary cross-sectional shape after or at the time of extruding the resin, so that the finished dimensions vary greatly. And the quality of the surface is degraded, resulting in unstable quality. On the other hand, in the second prior art, when the resin is extruded, the resin is rubbed against the movable shutter, leaving a mark on the surface of the product. Further, when the movable shutter is closed, surplus resin must be discarded, so that the amount of resin is wasted. An object of the present invention is to provide a resin extruder capable of forming a resin molded product having a small dimensional variation and a good surface appearance. A second object of the present invention is to provide a resin extrusion molding apparatus with less waste of resin. [0007] In order to solve the above-mentioned technical problems, the technical means adopted in the first aspect of the present invention is a technical means capable of molding a portion of a resin molded article whose sectional shape does not change. A first mold and a second mold slidably disposed on the first mold to form a cavity between the first mold and at least a portion in which a cross-sectional shape of the resin molded product changes; A driving device for driving at least one of the first and second molds in the longitudinal direction of the resin molded product, a resin extruding device for injecting resin into the cavity, and a driving device.
Mold position detecting means for detecting the position of the first or second mold to be moved
And a resin pressing section based on the output signal of the mold position detecting means.
And a control device for controlling the amount of resin extruded by the extruding device . According to the first aspect of the present invention, since the second mold can mold a portion where the cross-sectional shape of the resin molded product changes, there is no processing after extruding the resin. Further, the dimensional variation can be further reduced without deteriorating the appearance of the resin molded product. It is also driven by a driving device
Mold position detecting means for detecting the position of the first or second mold;
Based on the output signal of the position detection means,
Because it has a control device to control the resin extrusion amount,
Compatible with changes in resin extrusion due to changes in cross-sectional shape
Can reduce excess resin
You. According to a second aspect of the present invention, there is provided a mold position detecting means for detecting a position of the first or second mold driven by the driving device, and a resin extruding device of the resin extruding device based on an output signal of the mold position detecting means. Since the control device for controlling the amount is provided, it is possible to cope with a change in the amount of resin extruded due to a change in the cross-sectional shape, and it is possible to reduce excess resin. FIGS. 1 to 5 are views of a resin molded product molded by the resin extrusion molding apparatus of the present embodiment,
Reference numeral 10 denotes a window molding which is attached to the periphery of a windshield (not shown) of the vehicle. The wind molding 10 includes first and second protrusions 11 and 12 for holding a windshield, third and fourth protrusions 13 and 14 for holding a vehicle body (not shown), and a windshield. A fifth protruding portion 15 which is located on a side edge and forms a rain gutter together with the first protruding portion 11 is formed. A resin extrusion molding apparatus for molding the above-mentioned window molding 10 will be described with reference to FIGS. 6 and 7. FIG. The resin extrusion molding apparatus includes a first mold 20,
And a second mold 30. The first mold 20 includes a fixed support 21 provided with a resin inlet 21a, and a first mold member 22 installed on the fixed support 21 and capable of forming the third and fourth protrusions 13 and 14. And a second mold member 23 capable of forming a part of the second protrusion 12, and a holding member 25 for holding the second mold 30 via a bearing 24. On the other hand, the second die 30 holds the fixed support 21 on the movable member 35 slidable in the longitudinal direction of the wind molding 10 via the holding member 25 and the bearings 31, 32, 33, 34, and the movable member 35. A third part that can be formed to form a part of the first protrusion 11 and a part of the second protrusion 2
And the fifth protruding portion 15 which is held by the movable member 35 together with the third die member 36 and slides the first die member 22 via the bearing 37, and further changes the cross-sectional shape. And a possible fourth mold member 38. The first to third mold members 22, 23, and 36 have a fixed mold shape as shown in FIG. 7 in order to form a portion where the cross-sectional shape of the wind molding 10 does not change. The fourth mold member 38 has a portion 3 where the fifth protrusion 15 is formed as shown in FIG. 6 in order to form a portion (fifth protrusion 15) where the cross-sectional shape of the wind molding 10 changes.
8a and a portion 38b where the fifth protrusion 15 is not formed. A cavity 40 is formed by the first mold 20 and the second mold 30 having the above configuration. The cavity 40 is connected to two resin extruders 41 and 42. One resin extruding device 41 extrudes the resin by a fixed amount when the moving speed of the second mold 30 is constant. This is to increase the amount of resin to be extruded when the protrusion 5 is at the position where the protrusion 15 is molded. The driving device 50 includes a motor (not shown),
It is composed of a pinion gear 51 interlocked with a motor via a speed reducer (not shown), and a rack 52 fixed to a wall 52 and engaged with the pinion gear 51. The motor is
The rotation of which is controlled by an electronic control unit ECU,
The electronic control unit ECU determines the movement speed of the second mold 30 calculated from the rotation speed of the motor and the rotation angle sensor 54 that detects the rotation angle of the pinion gear 51 serving as mold position detection means. From the position, the resin extrusion device 4
1 and 42 are for controlling the extrusion amount of the resin. Further, the electronic control unit ECU controls the motor to rotate forward and backward, and reciprocates the second mold 30 in the direction of the arrow in FIG. In addition, the present invention is not limited to the reciprocating drive of the second mold 30, and a continuous molding may be performed by connecting and circulating a plurality of molds. In this embodiment having the above configuration, the second mold 3
For example, when one is driven from the right end to the left end in FIG. 6, one window molding 10 is formed, but a plurality of second dies 30 are connected in the longitudinal direction of the window molding 10. Thereby, a plurality of wind moldings 10 can be formed at once, and high productivity can be obtained. In this embodiment, the second mold 30 is used to mold the portion (fifth projecting portion 15) of the window molding 10 in which the cross-sectional shape changes. There is no
Can be further reduced without deteriorating the external appearance. A rotation angle sensor 54 for detecting the position of the first die 20 or the second die 30 driven by the driving device 50.
And an electronic control unit ECU for controlling the amount of resin extruded by the resin extruding devices 41 and 42 based on the output signal of the rotation angle sensor 54. It is possible to reduce excess resin. According to the first aspect of the present invention, since the second mold is capable of molding a portion where the cross-sectional shape of the resin molded product changes and is not processed after extruding the resin, The dimensional variation can be further reduced without deteriorating the appearance of the resin molded product. In addition, the drive
Mold position detecting means for detecting the position of the first or second mold to be moved
Step and resin extrusion based on output signal of mold position detection means
Control device to control the resin extrusion amount
Change in resin extrusion due to changes in cross-sectional shape
To reduce excess resin.
Can be. [0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a perspective view of a window molding (resin molded product). FIG. 2 is a sectional view taken along the line AA of FIG. 1; FIG. 3 shows a sectional view taken along the line BB of FIG. 1; FIG. 4 shows a sectional view taken along the line CC of FIG. 1; FIG. 5 is a sectional view taken along the line DD of FIG. 1; FIG. 6 shows a top view of the resin extrusion molding apparatus according to the present invention. 7 shows a sectional view taken along the line EE of FIG. 6; [Description of Signs] 10 ... Wind molding 11 ... First projection 12 ... Second projection 13 ... Third projection 14 ... Fourth projection 15 ... Fifth projection Part 20: First mold 30: Second mold 40: Cavities 41, 42: Resin extruding device 50: Driving device 54: Rotation angle sensor

Continuation of front page (56) References JP-A-5-31784 (JP, A) JP-A-5-185832 (JP, A) JP-A-5-201249 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) B29C 47/00-47/96

Claims (1)

(1) A first mold capable of molding a portion of a resin molded article whose cross-sectional shape does not change; and a first mold slidably disposed on the first mold. A second mold that forms a cavity between the mold and a mold that can mold at least a portion where the cross-sectional shape of the resin molded article changes; and at least one of the first and second molds is the resin molded article. A driving device that drives the resin in the longitudinal direction, a resin extruding device that injects resin into the cavity, and a position of the first or second mold that is driven by the driving device.
Die position detecting means for detecting the position , and the resin extrusion based on an output signal of the die position detecting means.
And a control device for controlling the amount of resin extruded by the extruder.