JPH0529713U - Mold clamping device - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the capital investment by using a mold clamping device with a simple structure. [Structure] Elevating mechanisms 4 and 5 for guiding the upper die 10 and only raising and lowering the upper die 10 are installed on the upper part of the machine frame 2, and the lower die 11 is attached to the air 1
It is installed on the machine base 1 via three springs, the columns 9 and 14 are respectively arranged on the upper die and the machine platform, and when the upper die and the lower die are matched with each other, both the columns are clamped and fixed to each other. When air is supplied to the air spring, the lower mold rises and the upper mold is supported by the machine base by the upper and lower columns, so that the mold clamping force is generated by the force of the air spring.
After molding, disconnecting the upper and lower columns and removing the air from the air spring causes the lower mold to descend and release.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mold clamping device for a molding die that molds a resin molded product or the like.

[0002]

[Prior Art]

 Recently, FRP (glass fiber reinforced resin) products have come to be used for various molded products such as automobile outer panels. In the case of molding such a fiber-reinforced resin molded product, for example, in the case of an engine hood, in order to secure the rigidity, strength, etc. of the molded product, a plurality of reinforcing fibers such as glass fibers are layered in advance in a mat shape. Resin transfer molding (hereinafter referred to as RTM) is used in which the glass fiber mat is set in a mold and molten resin is injected into the mold for molding. The mold used for RTM has a low resin injection pressure, and a lightweight mold using a resin mold or an electroformed shell is used. In RTM, the resin injection pressure is low, and in the case of automobile outer panels, the required mold clamping force is usually several tens of tons, but the molding cycle requires several tens of minutes. To open and close the RTM mold, the upper mold is generally hung by a hoist to move up and down, and the clamping force is clamped with bolts and nuts attached to the outside of the mold, or a pin-block pushing type with a hydraulic cylinder. Has been adopted. There is also a press that uses an off-the-shelf press to open and close the mold and generate clamping force.

Japanese Utility Model Laid-Open No. 56-44115 discloses a press for connecting an upper die and a lower die by a hydraulic cylinder to elevate and lower, and a mechanism for raising and lowering a piston rod by a sprocket and a worm driven by a chain. Are listed. In Japanese Utility Model Laid-Open No. Sho 64-1910, an air bag is interposed between a base plate supporting a lower die and a frame, and the air bag is inflated by air pressure to clamp the die. Is listed.

[0004]

[Problems to be solved by the device]

 Off-the-shelf presses are very uneconomical to use for RTM molding, which is expensive and has a long molding cycle. The press described in Japanese Utility Model Laid-Open No. 56-44115 also uses a fluid cylinder, so that the apparatus is expensive. The mold described in Japanese Utility Model Laid-Open No. Sho 64-1910 is not suitable for molding by RTM because it is difficult to fit the upper mold and the lower mold together.

The present invention solves the above problems and configures the mold opening and closing and the mold clamping device of a mold having a low molding pressure such as RTM and a long molding cycle with a simple structure, and the entire device is inexpensive. The purpose is to reduce the capital investment so that it can be manufactured.

[0006]

[Means for Solving the Problems]

 The present invention installs an elevating mechanism that guides the upper die on the upper part of the machine frame and only elevates and lowers it, and installs the lower die on the machine base via an air spring. This is a mold clamping device for a molding die in which support columns are respectively arranged, and when the upper mold and the lower mold are matched with each other, the both columns can be clamped and fixed to each other.

[0007]

[Action]

 Lower the upper mold to match the mold, and fix the upper and lower struts together. Next, when air is supplied to the air spring, the lower mold rises, and the upper mold is supported by the upper and lower columns on the machine base, so the mold clamping force is generated by the force of the air spring, and the reaction force is the reaction force. Receive at. After molding, disconnect the upper and lower columns and remove the air from the air spring, and the lower mold will drop by its own weight. The upper mold is lifted by the lifting device to open the mold.

[0008]

【Example】

 FIG. 1 is a front view of an embodiment of the present invention, and FIG. 2 is a side view excluding one column. An upper pedestal 3 is attached to the base 1 with two columns 2 and 2, and an elevating device for the upper dies 6 having the upper die 10 attached thereto is installed. A publicly known hoisting device can be used as this lifting device. In the figure, the guide 7 of the upper mount 6 is suspended by the chain 5 which is reciprocally driven by the drive motor 4, and the guides 7 are installed in the columns 2 and 2, respectively. Guide rails 8 and 8 are shown to be lifted and lowered. Upper columns 9 are fixed to four corners of the upper frame 6. On the other hand, the lower die 11 is attached to the base plate 12, the air spring 13 is installed between the base plate 12 and the base 1, and the bifurcated lower columns 14 are fixed to the base 1 at the four corners around the lower die. A pedestal 15 for the base plate 12 is provided.

Before molding, the upper mold 10 is raised to the state shown in the figure, and when the drive motor 4 is operated to extend the chain 5, the guide 7 of the upper mold base 6 supporting the upper mold 10 is guided by the guide rails 8. The lower mold 11 is matched with the upper mold 10 by being guided to the lower mold 11. Since the RTM molding die is provided with positioning on the die itself, the guide 7 of the upper die stand 6 may be a low precision guide mechanism such as a roller reel guide. In the state where the molds are matched, as shown in FIG. 3, the upper support column 9 fits between the lower support columns 14. Fitting holes 9a and 14a are provided in the upper and lower columns, respectively, and wedges 15 are inserted into these holes to fix them. When air is sent to the air spring 13, the base plate 12 rises, and the upper die 10 is supported by the base 1 by the upper strut 9 and the lower strut 14. Therefore, the force of the air spring 13 generates a mold clamping force, so that the molding die The required clamping force is obtained, and the reaction force is received by the base 1, so there is no effect on column 2. After molding, the air of the air spring 12 is slightly evacuated, the base plate 12 is slightly lowered, the wedge 15 is removed, and then the air of the air spring 13 is evacuated, the lower mold 11 further descends together with the base plate 12. It opens and is supported by the pedestal 15. The upper mold 10 is lifted by the lifting device to open the mold, and the molded product is taken out.

The upper die lifting device is responsible only for the lifting action of the upper die and has nothing to do with die clamping. Therefore, the guide mechanism is a low-precision mechanism, and the die clamping force is applied to the column etc. Since it is not transmitted, the rigidity of the entire upper lift mechanism is low, and the device can be manufactured at low cost.

Although the RTM molding die has been described in the above embodiments, the present invention can be applied to molding dies of other molding methods that are lightweight and have a low molding pressure.

[0012]

[Effect of the device]

 INDUSTRIAL APPLICABILITY The present invention does not require a high-rigidity pedestal or a high-precision guide mechanism, and can have a simple structure for the mold opening and closing and the mold clamping device, which makes it possible to manufacture the device inexpensively and reduce capital investment. ..

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a side view excluding the column of FIG.

FIG. 3 is an enlarged view of a main part of FIG.

[Explanation of symbols]

1 Base 2 Column 3 Upper Frame 4 Drive Motor 5 Chain 6 Upper Frame 7 Guide 8 Guide Rail 9 Upper Column 10 Upper Model 11 Lower Model 12 Base Plate 13 Air Spring 14 Lower Column

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display area B29L 31:30 4F

Claims (1)

[Scope of utility model registration request] 1. An elevating mechanism that guides an upper die to raise and lower the upper die only is installed on the upper part of the machine frame, and the lower die is installed on the machine base via an air spring. A mold clamping device for a molding die, characterized in that each of the columns is provided with a column, and when the upper mold and the lower mold are matched with each other, the columns can be clamped and fixed to each other.