JPS5955711A - Structure of main forming dies - Google Patents

Abstract

PURPOSE:To close all forming dies uniformly under pressure and to improve uniformity and workability of a product by a method wherein floating bases are slided vertically on the lower part of the forming dies, a template and an air- tight chamber are formed by a flexible expansion pipe at the bottom and each air-tight chamber is connected through a pressure passage. CONSTITUTION:A parting surface D in each cavity is varied by irregularity of dimensional accuracy in heights of many sets of compression molds 3, 4 to make positional differences E. Press-forming pressure is converted as reaction into liquid medium pressure in an air-tight chamber C produced by a flexible expansion pipe 1 by which the floating base 2 is held freely. This liquid pressure is distributed equally by a pressure passage 7 and all of the molds are clamped and compressed equally. This equal mold-closing pressure improves dimensional accuracy of a formed product and bad distribution of pressure by bad combination accuracy of the main molds and by a pressure device of bad accuracy is removed by self-pressure-controlling function.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a molding mold having a plurality of dispersed products used for compression molding of rubber, synthetic resin, etc.

Conventionally, when pressure molding materials such as rubber or synthetic resin that are relatively small and have a simple shape, the cavities that form the product are set as a set of molds, and a pair of molds for molding multiple molds are placed in an appropriate position. A structure is used in which the mold is constructed by incorporating it into the main mold, but when molding with such a mold, the combined height of each mold may be uneven,
Mold clamping of each mold may be caused by many negative factors such as poor manufacturing accuracy of the main mold, poor parallelism and rigidity of the molding pressure plate, or lack of dynamic strain accuracy inherent to the molding press. The pressure is not constant, and therefore the molding surface pressure is different for each cavity, making it difficult to obtain a homogeneous product and having poor workability.

Therefore, the reality is that a great deal of cost and labor is required both in terms of mold production and precision control.

The object of the present invention is to provide a main mold for molding which can eliminate such drawbacks and uniformly apply molding pressure to the molding die.

A detailed description will be given below with reference to the drawings.

The present invention provides a pair of main mold bases for molding consisting of a mold plate A, a lower mold plate B, and a guide pin 6 for guiding the opening/closing movement thereof, as shown in the drawings, at least one of the mold plates ( In the drawing, it is made up of a plurality of floating pedestals 2 holding and fixing a plurality of lower molding molds 4 constructed on a lower mold plate B). The floating pedestal 2 is a flexible extensible tube 1 having pressure resistance such as a diaphragm plate or multiple bellows, and is airtightly joined to the lower mold plate B to form an airtight chamber C. This airtight chamber C is connected to and sealed with a plurality of other mold floating pedestals 2 by a communication path 7, and a liquid having high pressure and heat resistance, such as a liquid medium such as silicone oil, is injected into the airtight chamber C including the communication path 7. The container is sealed and filled, and the floating pedestal 2 can be freely set at each relative position. The outer shoulder portion of the floating pedestal 2 is mounted with a support plate 8 so as not to move beyond the allowable displacement of the flexible telescoping tube 1.

A molding upper mold 3 and a molding lower mold 4 having a predetermined product cavity 5 are assembled into the main molding mold constructed as described above, and rubber or the like is supplied into the cavity and pressure molded.

Next, to explain the usage condition of the present invention, the mold parting surface changes for each cavity due to irregularities in height dimensional accuracy of the compression molding molds 3 and 4 in which a large number of increased numbers are arranged. , a positional difference E occurs, but the press molding force is converted as a reaction force into the pressure of the liquid medium in the airtight chamber C composed of the flexible extensible tube 1 that freely supports the floating pedestal 2, and this liquid pressure By equally distributing the pressure in the pressure communication path 7 connecting the airtight chambers C, all the molds are uniformly clamped and pressurized.

This uniform mold clamping pressure dramatically improves the dimensional accuracy of molded products.

Furthermore, problems with pressure distribution due to poor combination precision of the main molds or poor precision of the pressure mechanism can also be resolved by the above-mentioned self-pressure adjustment function, thus expanding the tolerance for dimensional accuracy in manufacturing molds, etc. This made it possible to manufacture it at a low cost.

As described above, by using the molding main mold of the present invention, it is possible to obtain a uniform clamping pressure distribution regardless of the unevenness of the combined height dimensions of the molding molds, and it is possible to obtain a uniform mold clamping pressure distribution. It is possible to correct errors in the flatness and parallelism of the molded product, and also compensate for the lack of accuracy and rigidity of the molding pressure surface plate, pressure mechanism such as the press machine, or the press body. It is an ideal main mold structure for molding that stabilizes dimensional accuracy, improves quality, reduces defects, and at the same time greatly improves workability and facilitates maintenance management of molds and press machines. .

[Brief explanation of the drawing]

The drawings are partial cross-sectional views showing embodiments of the present invention. A...Upper template B...Lower template C...Airtight chamber D
... Parting surface E ... Parting surface position difference 1 ... Flexible expansion tube 2 ... Floating pedestal 3 ... Upper mold 4 ... Lower mold 5 ... Product cavity 6・
...Guide pin 7...Pressure communication path 8...Support plate Patent applicant Uchiyama Kogyo Co., Ltd. l O7/kl k3

Claims (1)

[Claims] In a main mold for molding products such as rubber or synthetic resin, in which multiple sets of upper and lower molding molds are each attached individually to form a product cavity; At least one of them has a floating pedestal that slides up and down and accommodates lateral movement, and a mold is fixed to the top of the pedestal, and the bottom of the pedestal is made airtight with the mold plate by a flexible telescopic tube. After joining, an airtight chamber is formed, each airtight chamber is connected with an appropriate pressure communication path, and an appropriate amount of liquid medium is hermetically filled, and the floating pedestals are balanced at each molding position and pressurized for molding. The main mold structure for molding is characterized by the following features: