JPH091584A - Method for manufacturing expansion / contraction operation member of pump - Google Patents

Abstract

PURPOSE: To provide a method for manufacturing an expansion and contraction- working component of a pump capable of joining simply and integrally an expanding and contracting cylindrical material and a filling component together. CONSTITUTION: A bellows structured expanding and contracting cylindrical material 1 having a contact surface at an opening fringe is formed by blow molding and besides, a filling component 3 having a fitting flange is formed by injection molding. Then, the surface contact part 8 is integrated by insert molding and besides, a fitting part 7 is formed at an end part of the expanding and contracting cylindrical material 1 by injection molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION There is a type of pump that discharges or sucks fluid by contracting or expanding a bellows-shaped tubular body to change the volume of the tubular body. In this case, the larger the volume change rate with respect to the expansion / contraction deformation of the tubular body, the larger the pump pressure. Therefore, by inserting a filler having a smaller volume than the inner diameter of the bellows into the cylindrical body of the bellows structure and closing the space with a small volume change rate, a pump operating member with an increased volume change rate of the cylindrical body is provided. Are known. The present invention relates to a manufacturing method for molding a pump operating member having such a structure with resin.

[0002]

2. Description of the Related Art Conventionally, an expansion / contraction cylindrical body is first formed by blow molding, and a separately injection-molded filling member is inserted into the expanding / contracting cylindrical body. It was heated and melted at a high frequency to be integrated.

[0003]

However, those bonded with an adhesive are easy to peel off, and those using high frequency are
There has been a problem in production that the high frequency irradiation portion is limited so that the high frequency is not applied to an unnecessary portion.

An object of the present invention is to solve the above-mentioned conventional problems and to simply and integrally join the expansion / contraction cylindrical body and the filling member.

[0005]

In order to achieve the above object, in the present invention, first, an expansion / contraction cylindrical body having a bellows structure having a contact surface at an opening edge is formed by blow molding, and a mounting flange is separately formed by injection molding. Forming a filling member having. Then, the filling member is fitted into the expansion / contraction cylindrical body, the lower surface of the mounting flange of the filling member is brought into surface contact with the contact surface of the expansion / contraction cylindrical body, and the mold is loaded, and the surface contact portion is inserted. They are integrated by molding, and at the same time, a mounting portion is formed at the end of the expansion / contraction tubular body.

[0006]

By forming the expansion / contraction cylindrical body by blow molding, a bellows structure with a deep fold can be easily formed. By forming the filling member by injection molding, it is possible to manufacture a thick member that is hard and is not easily deformed by pressure. The lower surface of the mounting flange of the filling member is loaded into the insert mold in a state where the lower surface of the mounting flange is in surface contact with the contact surface of the expansion / contraction cylindrical body, and the contact surface is strongly pressed by the molding pressure to be in close contact. Therefore, even if the dimensions of the expandable / contractible cylindrical body vary to some extent, the insert-molded high-pressure resin is blocked at the surface contact portion and does not leak out elsewhere. Therefore, both the filling member and the expansion / contraction tubular body are firmly bonded together. Moreover, simultaneously with this joining step, the mounting portion of the end portion of the expansion / contraction operation member can be accurately molded. The completed expansion / contraction operation member is attached to the pump via the mounting portion.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 is a partial cross-sectional view of a bellows-structured expansion / contraction cylindrical body 1 having both ends opened. The expansion / contraction tubular body 1 is formed by blow molding to form an abutting surface 2 on the opening edge.

FIG. 2 is a partial sectional view of the filling member 3.
The filling member 3 has a bottomed cylindrical shape and is formed by injection molding. Then, the mounting flange 4 is integrally projected on the outer circumference of the opening, and four stopper bosses 5 are arranged at equal intervals on the upper surface of the mounting flange 4.

The filling member 3 and the expansion / contraction cylindrical body 1 are integrated by the following procedure. First, the filling member 3 is opened 6
Further, it is inserted into the expansion / contraction cylindrical body 1, the lower surface of the mounting flange 4 is placed on the contact surface 2, and both are brought into surface contact with each other, and in this state, the filling member 3 and the expansion / contraction cylindrical body 1 are inserted into the insert mold ( (Not shown). Then, resin is injected into this mold and heated and pressed to form the mounting portions 7 above and below the expansion / contraction cylindrical body 1, and at the same time, the surface contact portion 8 between the filling member 3 and the expansion / contraction cylindrical body 1 is formed. Integrate (Figure 3). Reference numeral 9 denotes a protrusion formed on the mounting portion 7.

The expansion / contraction cylindrical body 1 is formed by blow molding to form a deep bellows structure. Since the dimensional accuracy of blow molding is lower than that of injection molding, the dimension of the expansion / contraction tubular body 1 may be slightly different. However, the lower surface of the mounting flange 4 and the contact surface 2 come into surface contact with each other, and the molding pressure of insert molding is applied to this surface contact portion 8, so that the lower surface of the mounting flange 4 and the contact surface 2 come into close contact with each other. Therefore, for example, as shown in FIG.
Even if a gap is formed between the high-pressure resin and the side surface, the insert-molded high-pressure resin does not leak from the fitting portion of the expansion / contraction cylindrical body and the filling member.

The expansion / contraction operation member 10 of the resin pump manufactured as described above repeatedly compresses and expands to deliver various fluids. Since the pump pressure increases as the volume change rate of the expansion / contraction tubular body 1 with respect to the expansion / contraction deformation increases, the use of the pump expansion / contraction actuating member 10 in which the filling member 3 having a constant volume is inserted in the central portion of the expansion / contraction tubular body 1 is lightweight. It is a compact pump with high pressure.

Expansion / contraction cylindrical body 1, filling member 3 and mounting portion 7
All the resins for forming are made of the same material (for example, polypropylene), and the boundary portions of the respective members are melted and integrated.

Further, when the expansion / contraction operation member 10 of such a resin pump is used, there is no complicated machine or mechanism at the portion which actually contacts the liquid, and the resin bellows structure makes it possible to use a resin having a high chemical resistance. By using it, it can be used as a detergent solution supply part of a dishwasher or for delivering a strongly acidic or strongly basic solution.

Although the filling member 3 is cylindrical as described above, it may be cylindrical. The cylindrical shape is lighter than the cylindrical shape and can save material.

[0015]

In summary, according to the present invention, the expansion / contraction cylindrical body having the bellows structure having the contact surface at the opening edge is formed by blow molding, and the filling member having the mounting flange is formed by injection molding. The filling member is inserted into the expanding / contracting tubular body, and the lower surface of the mounting flange is brought into surface contact with the abutting surface of the expanding / contracting tubular body and loaded into an insert mold, and the surface contact portion is subjected to insert molding. Since the mounting portion is formed at the end of the expansion / contraction tubular body while being integrated, the expansion / contraction operating member of the pump in which the expansion / contraction tubular body and the filling member are firmly integrated can be easily manufactured. Further, since the mounting portion is formed at the end of the expansion / contraction tubular body by insert molding, the mounting portion can be accurately molded, and the completed expansion / contraction operating member can be accurately assembled to the pump via the mounting portion. Play.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of an expansion / contraction cylindrical body.

FIG. 2 is a partial cross-sectional view of a filling member.

FIG. 3 is a partial cross-sectional view of a state in which a filling member is inserted into the expandable / contractible cylindrical body, filled with resin, and cured.

FIG. 4 is an enlarged view of a main part of FIG. 3;

[Explanation of symbols]

 1 Expansion / contraction cylindrical body 2 Contact surface 3 Filling member 4 Mounting flange 7 Mounting part 8 Surface contact part

Claims (1)

[Claims] 1. A blow-molding expandable cylinder having a bellows structure having an abutting surface at the opening edge is formed, and an injection molding is performed to form a filling member having a mounting flange. Insert the filling member into the insert mold with the lower surface of the mounting flange in surface contact with the abutting surface of the expansion / contraction cylindrical body, and integrate this surface contact portion by insert molding and expand / contract. A method for manufacturing a pump expansion / contraction operating member, characterized in that a mounting portion is formed at an end portion of a tubular body.