JPH0357457Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an injection head structure for a reaction injection molding apparatus.

(Prior art) So-called reaction injection molding, in which resin molded products are obtained by mixing and injecting a thermosetting resin and a curing agent into a cavity formed by an upper mold and a lower mold, is used to mold relatively complex shapes. It is widely used in the manufacture of automobile parts, such as bumpers, because it can be easily manufactured without causing sink marks or the like.

However, in the reaction injection molding equipment used for this reaction injection molding, an injection head for mixing and injecting the thermosetting resin and curing agent is attached to the mold, and the injection head cannot be used when changing the mold. The process (i.e., attachment and removal) was extremely troublesome. To deal with this problem, as described in Japanese Utility Model Application Publication No. 60-98620, the injection head is moved by an actuator provided on the mold mounting plate of the reaction injection molding apparatus, and the tip of the injection head is moved. It has already been proposed to be able to press against and separate from the mold injection port.

(Problems to be solved by the invention) In the case of the above-mentioned known example, although it has the advantage that mold replacement etc. can be performed independently of the injection head, it requires space to install the actuator for driving the injection head, and the device The problem arises that this leads to increased complexity and larger size.

This invention was made in view of the above points,
The object of this invention is to have an extremely simple structure, to be able to adjust the pressing force of the injection head to the mold, and to be able to reduce the installation space.

(Means for Solving the Problems) In the present invention, as a means for solving the above problems, a thermosetting resin and a curing agent are mixed and injected into a cavity formed by an upper mold and a lower mold. In a reaction injection molding apparatus equipped with a head, the injection head is attached to a mounting plate of the lower mold, the distal end thereof faces upward, the upper half thereof is exposed above the lower mold, and a split injection port is provided in the lower mold. A mounting table is pivotably supported so as to be placed and fixed so that it can come into contact with the mounting table, and an upper mold side split is provided at the bottom of the mounting table, which becomes integral with the lower mold side split inlet when the upper mold is lowered. A cam member for swinging the mounting table is inserted so as to be able to move forward and backward in order to bring the upper half of the injection head into close contact with the injection port.

(Function) In the present invention, the following effects can be obtained by the above means.

That is, the injection head, which is placed and fixed on a mounting table that is swingably supported by the mounting plate of the lower mold, moves the cam member forward and backward when the upper mold is lowered (in other words, when the mold is clamped). As a result, the injection head is pressed against the mold injection port (consisting of split injection ports on the upper mold side and the lower mold side) with an appropriate pressing force, and the adhesion of the injection head to the mold is significantly improved. be.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in FIGS. 3 and 4, the reaction injection molding apparatus of this embodiment comprises an upper mold 1 which is moved up and down by a press device (not shown), and a lower mold 2 fixed to a mounting plate 4 on a bed 3. It is equipped with
A thermosetting resin and a curing agent are mixed and injected into a cavity 5 formed between both molds 1 and 2 to form a resin molded product. The upper mold 1
A fixed core 7 is fixed to a mounting plate 6 for the upper mold, a movable core 9 is supported via a guide pin 8 so as to be movable up and down relative to the fixed core 7, and ejects the resin molded product after opening the mold. It is made up of Note that the movable core 9 can be moved up and down by an appropriate driving means (not shown).

Further, an injection port is formed on one side of the upper mold 1 and the lower mold 2 for injecting a mixed liquid of a thermosetting resin and a curing agent into a cavity 5 formed between the two molds 1 and 2. Split injection ports 10a and 10b are provided, respectively. Reference numerals 11 and 12 are blocks that support the upper and lower parts of the split injection ports 10a and 10b, and 13 is a guide block that guides the movable core 9.

1 and 2 on the split injection port 10b side of the mounting plate 4 on the lower mold 2 side.
As shown in the figure, a pedestal 14 having a pair of bearings 15, 15 protruding from its upper surface is fixed, and the bearings 1
At 5 and 15, a mounting table 17 supporting an injection head 16 for injecting a mixed liquid of a thermosetting resin and a curing agent into the cavity 5 is swingably supported via a shaft 18. .

A pair of support legs 19, 19, through which the shaft 18 is rotatably passed, are protruded from the lower surface of the mounting table 17, and a cam member 25, which will be described later, is mounted on the lower surface of the support legs 19, 19. Slanted surface 19 serving as a contact surface
a, 19a are formed. Further, on the upper surface of this mounting table 17, supporting members 20, 20 for mounting and fixing the injection head 16 are provided.
are protruded at predetermined intervals in the axial direction of the
A cushion material 21 made of hard rubber and having an arc-shaped recess is provided on the upper surface of each support member 20 so that the cylindrical body 16a of the injection head 16 can be easily placed thereon. In addition, this mounting table 17
The injection head 16 placed and fixed on the mounting table 17 is configured so that its tip (in other words, the nozzle 22 side) faces upward and its upper half is exposed above the lower mold 2. By swinging, it can be brought into pressure contact with the split injection port 10b on the lower die side. In this embodiment, the upper surface of the mounting table 17 is formed into a slope 17a that slopes upward toward the lower mold 2 side, and support members 20, 20 are provided protruding from the slope 17a at the same height. By placing the injection head 16 on the injection head 20, the injection head 1
Although the tip of 6 is facing upward, the mounting table 17
The tip of the injection head 16 can also be directed upward by making the upper surface a horizontal plane and by changing the height of the support members 20, 20 back and forth. Reference numeral 23 is a spacer provided at the tip of the injection head 16 and is substantially pressed against the mold, and 24 is a stopper supporting the rear end of the injection head 16.

A wedge-shaped cam member 25 having a cam surface 25a that contacts the inclined surfaces 19a, 19a of the support legs 19, 19 is movable between the support legs 19, 19 of the mounting table 17 and the pedestal 14. is inserted. A screw member 27 that is screwed onto a washer 26 fixed to the end of the pedestal 14 is screwed into the cam member 25, and the cam member 25 is screwed into the cam member 25 depending on the degree of screwing of the screw member 27. is moved back and forth, and as the cam member 25 moves back and forth, the mounting table 17
can be swung in the direction of arrow A or B in FIG.

Next, the operation of the illustrated reaction injection molding apparatus will be explained.

After moving the movable core 9 of the upper mold 1 in the mold open state as shown in FIG. A cavity 5 is formed in between (see FIG. 3).

At this time, as the upper mold 1 descends, the divided injection port 10a on the upper mold 1 side changes to the divided injection port 10b on the lower mold 1 side.
At this time, when the screw member 27 is screwed and the cam member 25 is advanced, the mounting table 17 is aligned with the cam member 25.
is swung in the direction indicated by arrow A in FIG. 1, and the injection head 16 is brought into pressure contact with the split injection ports 10a and 10b of the mold.

Thereafter, a thermosetting resin and a curing agent are mixed and injected through the injection head 16 to form a resin molded article within the cavity 5.

As described above, according to this embodiment, the cam member 2
By moving the injection head 5 back and forth, the injection head 16 can be brought into pressure contact with the divided injection ports 10a and 10b with an appropriate pressing force.

It goes without saying that the present invention is not limited to the embodiments described above, and that the design can be modified as appropriate without departing from the gist of the invention.

(Effect of the invention) As described above, according to the invention, the injection head is mounted on the mounting plate of the lower mold with its tip facing upward and its upper half exposed above the lower mold. A mounting table is swingably supported to be placed and fixed so as to be able to come into contact with the split injection port on the lower mold side, and is integrated with the lower mold side split injection port when the upper mold is lowered at the lower part of the mounting table. Since the cam member for swinging the mounting table was inserted so as to be able to move forward and backward in order to bring the upper half of the injection head into close contact with the upper mold side split injection port, the injection head was placed and fixed on the swingable mounting table. In addition, it has an extremely simple structure in which a cam member that can move forward and backward is inserted into the lower part of the mounting table, and by moving the cam member forward and backward when the upper mold is lowered (in other words, when the mold is clamped), the injection head can be moved into the mold. The injection head can be brought into pressure contact with the inlet with an appropriately adjusted pressing force, and has the practical effect of significantly improving the adhesion of the injection head to the mold.

Furthermore, since the cam member is inserted into the lower part of the mounting table on which the injection head is placed and fixed, the installation space can be extremely reduced.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the main part (i.e., injection head) of a reaction injection molding apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken from FIG. 1, and FIGS. 3 and 4 are 1 is a partially sectional side view showing the reaction injection molding apparatus according to the embodiment of the present invention when the mold is closed and when the mold is opened; FIG. DESCRIPTION OF SYMBOLS 1...Upper mold, 2...Lower mold, 4...Mounting plate, 5...Cavity, 10a...Upper mold side split injection port, 10b...Lower mold side split injection port, 16...Injection head, 17 ...Placement table, 25...Cam member.

Claims (1)

[Scope of utility model registration request] In a reaction injection molding apparatus equipped with an injection head that mixes and injects a thermosetting resin and a curing agent into a cavity formed by an upper mold and a lower mold, the mold is pivotably supported with respect to a mounting plate of the lower mold. a mounting table for mounting and fixing the injection head in such a manner that the tip thereof faces upward, the upper half thereof is exposed above the lower mold, and can come into contact with a split injection port provided in the lower mold; , the mounting table is inserted into the lower part of the mounting table so as to be able to move forward and backward, and the upper half of the injection head is brought into close contact with the upper mold side split injection port which is integrated with the lower mold side split injection port when the upper mold is lowered. An injection head structure for a reaction injection molding apparatus, characterized in that it is equipped with a swinging cam member.