Plastic and nonmetallic article shaping or treating: processes – Mechanical shaping or molding to form or reform shaped article – To produce composite – plural part or multilayered article
Reexamination Certificate
1999-11-05
2002-08-06
Ortiz, Angela (Department: 1732)
Plastic and nonmetallic article shaping or treating: processes
Mechanical shaping or molding to form or reform shaped article
To produce composite, plural part or multilayered article
C264S263000, C264S267000, C264S275000, C264S297700, C264S297800, C425S121000, C425S123000, C425S134000, C425S438000, C425S444000
Reexamination Certificate
active
06428730
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a synthetic resin-made hollow member with an intermediate element incorporated therein, as well as an apparatus therefor, through the steps of previously incorporating the intermediate element such as a filter to between a pair of synthetic resin-made half bodies, and then bringing the two half bodies into abutment against each other and joining the two half bodies together at the abutted portion.
As the method for manufacturing a synthetic resin-made hollow member, there has conventionally been known, for example as shown in Japanese Patent Laid-Open Publication HEI 7-217755, a method employing a slide type injection molding technique (what is called die slide injection (DSI) molding). In this method, a pair of molding dies are provided, one molding die having one set of male molding portion and female molding portion for molding half bodies, and the other molding die having female molding portion and male molding portion opposed to those molding portions, where the one molding die is slidable relative to the other molding die in the direction in which the molding portions are arrayed. In this arrangement, after half bodies are simultaneously molded (primary injection), one molding die (slidable die) is slid relative to the other molding die (stationary die) so that the two half bodies left in the individual female molding portions are brought into abutment against each other, and then with the dies closed, molten resin is injected to peripheries of the abutted portion (secondary injection) so that the two half bodies are joined together.
This method employing the DSI technique is capable of enhancing the productivity to a great extent, as compared with the prior art in which the molding of half bodies and the abutment and joint of the half bodies would be done in separate processes. Still, the joint strength and the sealability of the abutted portion can be secured more stably than conventional cases in which half bodies would be joined together by bonding or thermal fusion processes.
It is to be noted that, in manufacturing a synthetic resin-made hollow member, the terms “primary injection (molding)” herein refer to an injection (molding) step in which half bodies to form a hollow member (molded article) are molded by injecting molten resin (primary resin) into a cavity defined by closing molding dies together. Also, the terms “secondary injection” refer to an injection step in which a pair of half bodies obtained by the primary injection (molding) step are joined together by bringing the pair of half bodies into abutment against each other and then injecting molten resin (secondary resin) to generally peripheries of the abutted portion.
Also for the manufacture of a synthetic resin-made hollow member with an intermediate element such as a filter incorporated inside, a high efficiency production using the DSI technique can be achieved, as disclosed in the aforementioned prior art publication, by performing the primary injection, then with the dies once opened, assembling a separately fabricated intermediate element to either one of half bodies, and thereafter, through die sliding and die closure processes, performing the secondary injection.
In this connection, in the DSI method, the position of the slidable die relative to the stationary die in the sliding direction naturally differs between before and after the sliding operation of the molding die (in other words, between primary injection and secondary injection). Therefore, particularly in the case of a multiple(e.g., 2)-yield molding apparatus capable of yielding a multiplicity (2) of molded articles simultaneously, the stationary die and the slidable die are both longer in length, so that a large eccentric load acts upon one or the other die closure, which makes the apparatus more prone to failures and the die-closing device more prone to eccentric wear. As a result, there has been a disadvantage of the method that the molding apparatus may incur shorter life or deterioration of the precision of molded articles.
In view of such problems, for example, Japanese Patent Laid-Open Publication HEI 9-76288 has proposed a so-called double DSI method in which sets of male molding portion and female molding portion as described above are provided in the stationary die in series in the die sliding direction, while slidable dies that operate independently of each other are provided in correspondence to the individual sets of molding portions.
According to this series type double DSI method, it becomes possible to make a uniform tightening load act upon the die closure, and besides since two slidable dies are provided separately from each other, the sliding amount of each slidable die can be made shorter, as compared with conventional counterpart (having one slidable die), so that the space can be saved.
When a synthetic resin-made hollow member with an intermediate element incorporated therein, such as a strainer with a filter incorporated therein, is manufactured by the DSI method, it has been conventional practice that after primary injection and before secondary injection, a separately fabricated intermediate element is assembled into either one of half bodies. In this case, however, there is a need of providing a step for manufacturing the intermediate element utterly separately from the steps for performing the molding and the abutting and joining of the half bodies, as well as a need of separately managing the intermediate element manufactured in this way as a part, which makes this method disadvantageous in cutting the manufacturing cost. Further, since the half bodies molded by the primary injection and the intermediate element manufactured separately are different in molding conditions as well as temperature and other conditions in the assembly, this method is disadvantageous also in attaining improvements in assemblability and assembly precision.
Also, when the intermediate element manufactured separately as described above is set to the half bodies, it would be conceived to provide an automatic assembler such as a robot outside the molding machine so that the intermediate-element incorporating step is automatized by assembling the intermediate element to the half bodies with this automatic assembler. For example, it is also possible to provide a holder (chuck) for clamping the intermediate element in a product takeout device (takeout robot) provided for use of taking products out of the injection molding machine, so that the intermediate element is clamped and traveled by this holder so as to be set to either one of the half bodies.
With the use of such an automatic assembler, in order to enhance the productivity by reducing the cycle time of production and to ensure a successful assembly precision, it is preferable that the distance for the intermediate element to be traveled is as short as possible.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a method, as well as an apparatus therefor, for manufacturing a synthetic resin-made hollow member with an intermediate element incorporated therein, the method being capable of molding hollow half bodies and an intermediate element and assembling them with the same dies, and yet the method involving a shorter travel of the intermediate element.
To achieve this object, in one aspect of the present invention, there is provided a method for manufacturing a synthetic resin-made hollow member with an intermediate element incorporated therein by, with the intermediate element placed between a pair of synthetic resin-made half bodies, bringing the half bodies into abutment against each other and joining the half bodies together at this abutted portion, the method comprising:
with use of a molding apparatus for slide type injection molding, the molding apparatus comprising: a stationary molding die having first and second hollow-member use stationary die portions in each of which a male molding portion and a female molding portion spaced from each other at a
Foley & Lardner
GP Daikyo Corporation
Ortiz Angela
LandOfFree
Method for manufacturing synthetic resin-made hollow member... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for manufacturing synthetic resin-made hollow member..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for manufacturing synthetic resin-made hollow member... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2920799