JP2812116B2 - Mixing head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixing head for producing a synthetic resin material by mixing at least one secondary component in addition to two chemically reactive main components,
In particular, the present invention relates to a mixing head suitable for producing a polyurethane resin material.

[0002]

2. Description of the Related Art Conventionally, as a mixing head of this type, for example, a technique disclosed in Japanese Patent Publication No. 63-56868 is known. FIGS. 5 to 7 schematically show this mixing head. A rod-shaped circulation control valve 54 is slidably inserted into a through hole 53 formed in a direction perpendicular to the axis of the head body 52. A rod-shaped discharge control valve 56 is slidably inserted into the through hole 55 formed in the axial direction. On the peripheral wall of the through-hole 53, two main discharge ports 57 for separately discharging two chemically reactable main components are provided to face each other. At the center of the circulation control valve 54, a channel 58 for introducing, for example, a coloring component as a secondary component is perforated. The channel 58 opens as a sub-discharge port 59 at the tip end surface of the circulation control valve 54, and Is discharged in the axial direction of the through hole 53.

The operation of the mixing head will now be described. First, FIG. 5 shows a state in which components are circulated. Since the circulation control valve 54 is advanced, each main component is transferred from the main discharge port 57 to the side of the circulation control valve 54. It circulates through the formed long groove 60.
Next, FIG. 6 shows the time of preparation for component discharge, and the discharge control valve 56
Retreats to open the through-hole 55, and prepares for retreat of the next circulation control valve 54. Next, FIG. 7 shows the time of component discharge, in which the circulation control valve 54 retreats and opens each main discharge port 57 to the through-hole 53, so that the two main components discharged from each main discharge port 57 The coloring component discharged from the sub-discharge port 59 is mixed to generate a synthetic resin material, which is injected into a molding die (not shown) through the through holes 53 and 55.

[0004]

However, in the mixing head, the auxiliary discharge port 59 is opened to the through hole 55 by the retreat of the discharge control valve 56 at the time of preparing the component discharge shown in FIG. The coloring component remaining in the channel 58 may leak out of the auxiliary discharge port 59 into the through hole 55. Since the leaked coloring component is mixed into the synthetic resin material generated at the beginning of the main shot, there is a problem that the mixing ratio of the coloring component temporarily increases and color unevenness occurs in the molded product.

If the channel 58 is clogged, the head body 52 is disassembled before the circulation control valve 5
4 and the inside of the channel 58 had to be cleaned. For this reason, there is a problem that disassembly of the head body 52 takes a great deal of time and maintenance is inferior, and when the circulation control valve 54 is extracted, oil in the cylinder 61 leaks out.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problem, to prevent a problem that a secondary component leaks from a sub-discharge port before a main component is discharged from a main discharge port, and to prevent a problem in which a It is an object of the present invention to provide a mixing head capable of keeping a mixing ratio of a secondary component constant and improving maintainability when a clogging occurs in a secondary discharge port and a secondary component flow path.

[0007]

In order to solve the above-mentioned problems, according to the present invention, a through-hole is formed in a head body, and a rod-shaped control valve is slidably inserted into the through-hole. Is mounted on the head body, and two main discharge ports for discharging two chemically reactable main components separately into the mixing chamber of the through hole are opposed to the peripheral wall of the through hole. In the mixing head provided, at least one sub-discharge port for discharging a secondary component to the mixing chamber is provided on the peripheral wall of the through-hole, and the main discharge port and the sub-discharge port slide on the control valve. The main discharge port and the sub discharge port are arranged on one orthogonal plane with respect to the axis of the through hole so as to be simultaneously opened and closed (claim 1).

It is preferable that a sub-nozzle having a sub-component flow path which can communicate with the sub-discharge port is detachably incorporated in the head body.

[0009]

According to the mixing head of the present invention, the main discharge port and the sub discharge port are arranged on a plane orthogonal to the axis of the through hole. Are simultaneously opened with respect to the through hole by the sliding of, and the ejection timings of the main component and the secondary component coincide. Therefore, the secondary component remaining in the secondary discharge port or the secondary component flow path in the previous shot does not leak into the through hole before the start of the main component discharge. Therefore, the mixing ratio of the secondary components in one shot can be kept constant. Also, since the sub-discharge port is provided on the head body side instead of the control valve side,
When the sub-discharge port or the secondary component flow path is clogged, it is not necessary to largely disassemble the head body or remove the control valve in maintenance. Therefore, the maintainability is improved, and even when a cylinder is employed as the drive means of the control valve, there is no fear that the oil leaks.

[0010] Further, if the sub-nozzle provided with the secondary component flow path which can communicate with the sub-discharge port is detachably incorporated into the head body, there is no need to disassemble the head body in the above-mentioned maintenance. By removing the sub-nozzle from the head body, the sub-ejection port and the sub-component flow path can be easily cleaned. Therefore, maintainability is further improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a three-component mixing head for producing a polyurethane resin material will be described below with reference to FIGS. As shown in FIG. 1, in the mixing head of the present embodiment, a head body 3 is attached to a cylinder 1 via a body flange 2, and a through hole 4 is formed at the center of each of the body flange 2 and the head body 3. ing. A circulation control valve 5 is slidably inserted into the through hole 4, and its base end is connected to the cylinder 1.
To the piston 6 via a holding plate 7.

A circulation control valve 5 is provided at both ends of the head body 3.
The sleeves 8 and 9 for slidingly guiding are inserted. The half of the sleeve 8 on the proximal end side is fitted into the body flange 2 so that the body flange 2 and the head body 3
Has a function of positioning the through holes 4 on the same axis. A pair of upper and lower long grooves 10 are engraved in the front half of the side peripheral surface of the circulation control valve 5, and a tip of a detent pin 11 screwed to the head body 3 is fitted into each long groove 10. As the piston 6 reciprocates, the circulation control valve 5 is guided by the sleeves 8 and 9 and slides between the forward position shown in FIG. 1 and the retracted position shown in FIG. The mixing chamber 12 is formed in the through hole 4 in front of the front end face of the mixing chamber 12.

As shown in FIGS. 2 and 3, the head body 3 at the position where the mixing chamber 12 is formed has a pair of upper and lower main nozzle insertion holes 13 and one sub nozzle insertion hole 14 on the side. The through hole 4 is formed in a direction orthogonal to the axis. The bottom wall 15 of each of the insertion holes 13 and 14 constitutes a part of the peripheral wall of the through hole 4. An outlet 16 and one sub-discharge port 17 opening to the mixing chamber 12 at right angles to the outlet 16 are formed.

The main discharge port 16 and the sub discharge port 17
Are opened and closed simultaneously by sliding of the circulation control valve 5,
As shown in FIG. 4, they are disposed on one orthogonal plane 18 with respect to the axis of the through hole 4. Further, the main discharge port 1 of the present embodiment
6 and the sub-discharge port 17 are formed in the same shape (round hole) and the same diameter. The main discharge port 16 and the sub discharge port 17
In the case where the shape and the size of are different, it is preferable that the positions of the edges of the main discharge port 16 and the sub discharge port 17 are aligned so that the retreating circulation control valve 5 starts to open the respective edges of the main discharge port 16 and the sub discharge port 17 at the same time.

Each main nozzle insertion hole 13 has a main nozzle 19 therein.
Is detachably inserted, and a nozzle holder 20 for holding and holding each main nozzle 19 is mounted on the outer surface of the head body 3. Each of the main nozzles 19 has a tapered orifice 21 communicating with the main discharge port 16 and a main component flow path 22 connected to the orifice 21. A supply port 23 connected to a supply pipe (both not shown) extending from the main component tank is provided inside each nozzle holder 20.
And a supply path 24 communicating with the main component flow path 22 of the main nozzle 19.
Are formed continuously.

A needle 25 is inserted through each nozzle holder 20 and the main nozzle 19, and an orifice 21 is provided at the tip thereof.
And a tapered valve portion 26 for opening and closing the valve. The needle 25 includes a screw portion 27 that is screwed to the nozzle holder 20, and a lock nut 28 is screwed to the screw portion 27. Then, by rotating the needle 25,
The discharge pressure of the main component can be adjusted by adjusting the opening degree of the orifice 21 by the valve section 26.

On the other hand, a recirculation hole 29 is formed in the head body 3 behind each of the main nozzles 19, the inner end of which is communicated with the long groove 10 of the circulation control valve 5, the outer end of which is closed with a screw plug 30, and The middle is connected to the return port 31 of the head body 3. The reflux port 31 is connected to the main component tank via a return pipe (not shown) so that the main component can be circulated to the main component tank when the circulation control valve 5 advances. The circulation control valve 5 has a plurality of annular grooves 32 on both sides of the long groove 10, and a sealing material (not shown) is formed in each annular groove 32 by a reaction-solidified polyurethane resin.

A sub nozzle 33 is detachably screwed into the sub nozzle insertion hole 14. This sub nozzle 3
A secondary component flow path 34 communicating with the secondary discharge port 17 is formed at the center of the nozzle 3, and a supply pipe 35 extending from a secondary component tank (not shown) is connected to the secondary component flow path 34. It is possible.

Next, the operation and effects of the mixing head of the present embodiment configured as described above will be described.

Two kinds of chemically reactable main components, that is, a polyol component and an isocyanate component which form a polyurethane resin material, are stored in separate main component tanks. For example, a supply pipe extending from the main component tank of the polyol component is provided. The supply pipe connected to the upper nozzle holder 20 and extending from the main component tank of the isocyanate component is connected to the lower nozzle holder 20. Further, a coloring component (a pigment dissolved in a polyol component) as a secondary component is stored in a secondary component tank, and the supply pipe 35 is connected to the secondary nozzle 3.
Connect to 3.

First, at the time of circulation of the components shown in FIG. 1, the circulation control valve 5 is advanced, so that the polyol component and the isocyanate component, which are the main components, respectively flow from the main discharge port 16 into the long groove 10 → the reflux hole 29 → the reflux port. It circulates through 31 to the main component tank.

Next, at the time of the component discharge shown in FIGS. 2 and 3, the circulation control valve 5 is retracted to open the main discharge port 16 and the sub discharge port 17 to the mixing chamber 12, so that as shown in FIG. The polyol component A, the isocyanate component B, and the coloring component C discharged from each of the main discharge ports 16 and the sub discharge ports 17
Are impact-mixed to produce a synthetic resin material, which is injected through a through hole 4 into a molding die (not shown).

At this time, both the main discharge port 16 and the sub discharge port 1
7 is simultaneously opened with respect to the mixing chamber 12 by retreating the circulation control valve 5, so that the discharge timings of the polyol component A, the isocyanate component B, and the coloring component C coincide. Therefore, the coloring component remaining in the secondary component flow path 34 in the previous shot does not leak into the through-hole 4 before the discharge of the polyol component A and the isocyanate component B is started. Therefore, the mixing ratio of the coloring components in one shot can be kept constant, and color unevenness of the molded product can be prevented.

The secondary discharge port 17 and the secondary component flow path 34
When clogging occurs, the sub-nozzle 33 is screwed out of the head body 3 and removed without disassembling the head body 3 or removing the circulation control valve 5.
7 and the secondary component flow path 34 may be cleaned. Therefore,
It is excellent in maintainability and there is no fear that oil in the cylinder 1 leaks.

The present invention is not limited to the above-described embodiment, but may be embodied with appropriate modifications without departing from the spirit of the present invention, for example, as follows.

(1) A second sub-discharge port (not shown) is provided on the peripheral wall of the through hole 4 at a position facing the sub-discharge port 17, and a secondary component flow path which can communicate with the sub-discharge port is provided. The auxiliary nozzle provided is detachably incorporated into the head body 3. If the coloring component is also discharged from the second sub-discharge port, the coloring component collides with the polyol component and the isocyanate component from both sides thereof, so that better mixing can be realized. Further, a coloring component of another color or a secondary component (a catalyst or the like) other than the coloring component can be discharged from the second sub-discharge port.

(2) The present invention is applied to a mixing head in which various synthetic resin materials other than the polyurethane resin material are mixed and produced.

[0028]

As described above in detail, according to the mixing head of the first aspect of the present invention, there is a problem that the secondary component leaks from the sub-discharge port before the main component is discharged from the main discharge port. And the mixing ratio of the secondary components in one shot can be kept constant. Further, when the sub-discharge port or the sub-component flow path is clogged, it is not necessary to disassemble the head body greatly or remove the control valve in the maintenance, thereby improving the maintainability.

According to the mixing head of the second aspect of the present invention, it is not necessary to disassemble the head body at the time of the maintenance, so that the maintainability is further improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a mixing head according to an embodiment of the present invention when components are circulating.

FIG. 2 is an enlarged cross-sectional view showing the vicinity of a nozzle during component ejection of the mixing head of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a perspective view showing the vicinity of a discharge port of the mixing head of FIG. 2;

FIG. 5 is a cross-sectional view of a conventional mixing head when components are circulating.

FIG. 6 is a cross-sectional view of the mixing head during preparation for component ejection.

FIG. 7 is a cross-sectional view of the mixing head during component ejection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 3 Head body 4 Through-hole 5 Circulation control valve 6 Piston 12 Mixing chamber 16 Main discharge port 17 Sub-discharge port 18 Orthogonal surface 33 Sub-nozzle 34 Secondary component flow path

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-107322 (JP, A) JP-A-58-90937 (JP, A) JP-A-57-150555 (JP, A) JP-A-63- 270109 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B29B 7/00-7/94

Claims (2)

(57) [Claims] 1. A through-hole is formed in a head body, a rod-shaped control valve is slidably inserted into the through-hole, and a driving means for the control valve is attached to the head body, so that a chemically reactable two-way control valve is provided. In a mixing head in which two main discharge ports for separately discharging a main component of a seed to the mixing chamber of the through hole are provided opposite to the peripheral wall of the through hole, a secondary component is discharged to the mixing chamber. At least one sub-discharge port is provided on the peripheral wall of the through-hole, and the main discharge port and the sub-discharge port are simultaneously opened and closed by sliding of the control valve. A mixing head arranged on one orthogonal plane to the axis of the mixing head. 2. The mixing head according to claim 1, wherein a sub-nozzle having a sub-component flow path capable of communicating with the sub-discharge port is detachably incorporated in the head body.