JPS5856343B2 - Injection molding machine for liquid resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an injection molding machine for liquid resin equipped with a static mixer in a mixing cylinder having a base agent supply section and a curing agent supply section. A diffusion plate having resin passage holes is provided, and a curing agent supply pipe is provided in contact with the center of the diffusion plate,
The present invention relates to an injection molding machine for liquid resin in which a dividing hole is formed at the tip of the curing agent supply pipe to open between the resin passing holes, and further, in the injection molding machine for liquid resin, the diffusion This invention relates to an injection molding machine for liquid resin, which is provided with a preliminary diffusion plate in which resin passage holes are bored at appropriate positions on the upstream side of the plate and resin passage holes that are shifted by half a pitch from the resin passage holes of the diffusion plate.

In general, there are various types of injection molding machines for liquid resin, but usually a mixed mixing (premix) type, a premix chamber type, a special screw type, etc. are used.

In the pre-mixing method, the base material and the curing agent are mixed in advance in an independent mixing device, and the mixture is supplied to a plunger and injected.

In this method, the curing reaction of the resin begins in the mixing device, so the pot life (pot life) is short, so the mixture must be handled quickly, and transportation from the mixing device to the injection molding machine is cumbersome. There is a drawback that there is, and
There was a drawback that cleaning the mixing device was troublesome.

In the one-type premix chamber, mixing devices are distributed for each injection molding machine, and only the necessary amount is mixed according to the operation of the injection molding machine, and the injection molding machine uses a conventional in-line screw type.

This method has the disadvantage that a mixing device is attached to each injection molding machine, which complicates the structure and increases the price.

In addition, the special screw one-type machine is an improved version of the screw of the conventional in-line screw type injection molding machine, and has a structure suitable for stirring liquid resin, which integrates the mixing device and the injection molding machine.

This method has disadvantages in that it has complicated moving parts, which causes many failures, complicates maintenance, makes it difficult to seal the liquid resin, and makes the device expensive.

Recently, in order to solve the problems of each conventional method as mentioned above,
One type of static mixer has been proposed.

In this method, an injection molding machine is configured with a mixing device that has no moving parts, that is, a static mixer, and the main material and hardening agent are both liquid, and are injected by the pressure of the material supply pump. Compared to the above-mentioned systems, this method has the advantage of being simpler in structure, less troublesome, easier to maintain, especially easier to clean, and, in addition, cheaper.

However, in the one-type static mixer,
If there is a time lag in the supply of the base agent and curing agent, a phenomenon occurs in which the group of single liquid agents caused by the time difference cannot be dispersed and remains as uneven mixing until the end.

This result has the drawback of inducing insufficient curing of the resin and deteriorating the mechanical strength and electrical insulation resistance of the molded product.

Moreover, in this method, the injection amount for each shot is intermittently supplied by starting and stopping the supply pump. Differences in supply time between the main resin and the curing agent inevitably occur due to differences in the shape and length of the resin transport pipes leading to the resin transporting device (device), as well as differences in viscosity on both sides.

The purpose of this invention is to take into consideration the problem of resin mixing due to the structural limitations of an injection molding machine based on the above-mentioned one-type static mixer, and to provide a structure in which a diffusion section is provided on the upstream side of the static mixer housed in the mixing cylinder. The present invention aims to provide an excellent injection molding machine for liquid resin, which eliminates the above-mentioned drawbacks and eliminates uneven mixing of the main resin and curing agent very efficiently.

The structure of the present invention in accordance with the above object is that when mixing the base agent and the curing agent, the base agent and the hardening agent are diffused and retained together in a diffusion section provided on the upstream side of the static mixer to cause a transfer delay time on both sides. Preliminary mixing is performed by collision and division on both sides within the transfer delay time to eliminate mixing unevenness caused by the supply time lag between the main agent and curing agent, and the subsequent static mixer completely mixes both sides with no time lag unevenness. The gist of this is that they can be mixed.

Next, an embodiment of the present invention will be described below based on FIGS. 1 to 3.

In FIG. 1, 1 is a mixing cylinder, which is equipped with a nozzle part 2 at its tip.

3 is a static mixer, which is installed on the upstream side of the nozzle section 2.

A diffusion section 4 is provided upstream of the static mixer 3, and the diffusion section 4 is composed of a diffusion plate 5 and a curing agent supply pipe 7.

The diffusion plate 5 is mounted at right angles to the axis of the mixing cylinder 1, and a plurality of resin passage holes 6 are bored on the surface of the diffusion plate 5 at appropriate intervals along the circumferential direction. There is.

Further, the curing agent supply pipe 7 is provided in contact with the first non-porous part located at the center of the diffusion plate 5 at a right angle, and a plurality of dividing holes 8 are bored at the tip thereof. It is set up.

The dividing holes 8 are open so as to face the second non-porous area between the resin passage holes 6 on the surface of the diffusion plate 5.

Note that 9 is an annular guide member that guides and directs the resin to the resin passage hole 6.

10 is a rectifying projection provided on the downstream side of the diffusion plate 5.

Further, on the upstream side of the mixing cylinder 1, a main agent supply pipe 11 extends concentrically so as to be coaxially fitted to the curing agent supply pipe 7 and tightly fitted to the diffusion plate 5. There is.

Reference numeral 12 denotes a cooling jacket provided around the outer periphery of the mixing cylinder 1 in the portion where the static mixer 3 is installed.

In the above configuration, when performing injection molding, a base material such as epoxy, polyester, urethane, silicone rubber, etc. is supplied into the mixing cylinder 1 through a base material supply pipe 11 by a base material supply pump.

When the base agent reaches the diffusion plate 5, a part of the base agent passes through the resin passage hole 6, but most of the base agent passes through the resin passage hole 6.
The resin collides with the non-porous part between them, reverses its flow and takes a detour, and then heads toward the resin passage hole 6 and passes through it.

During this time, there will be a delay in the transfer time of the base agent.

On the other hand, the curing agent transferred through the curing agent supply pipe 7 by the curing agent supply pump collides with the first non-porous part located at the center of the diffusion plate 5, and the curing agent is transferred to the first non-porous part provided at the tip of the curing agent supply pipe 7. The flow is divided by the dividing hole 8 and flows out to the outside.

During this time, there is a delay in the transfer time of the curing agent, and the curing agent then moves toward the resin passage hole 6.

At this time, the divided curing agent flows out into the second non-porous area between the resin passing holes 6 of the diffusion plate 5, and the above transfer time is not shortened to the resin passing holes 6. The delayed action of will be more effective.

In this way, the main agent that is reversed and detoured by the diffusion plate 5 and the curing agent that collides with the diffusion plate 5, is divided by the curing agent supply pipe 70 and the dividing hole 8, and flows outward remain in the vicinity of the diffusion plate 5, and the transfer time is shortened. There is a delay between the two, and during this time they collide with each other, causing a large disturbance in the flow and causing preliminary mixing.

In this way, the resin in which the uneven mixing caused by the supply time difference between the main resin and the curing agent due to the operation deviation of the supply pump is eliminated, is guided by the annular guide member 9 and passes through the resin passage hole 6 of the diffusion plate 5. The resin flows into the following static mixer 3 after being rectified by the rectifying protrusion 10. Within the static mixer 3, the resin is completely mixed by dividing, swirling, and reverse swirling for each section, and the resin is completely mixed at the tip. It is ejected from the nozzle part 2.

However, according to the present invention, although the base agent supplied into the mixing cylinder 1 is given a transfer delay time by the diffusion plate 5, a portion of the base agent is transferred through the resin passage holes 6 of the diffusion plate 5.
The disadvantage is that there is no delay in the transport time in that part, and as a result there is no collision with the curing agent, which can sometimes lead to insufficient overall premixing. There is.

Therefore, in view of the above problems, the second
The invention described above eliminates the above-mentioned drawbacks by providing a preliminary diffuser plate at a proper location upstream of the diffuser plate, and an embodiment thereof will be described below with reference to FIGS. 4 and 5.

In the figure, reference numeral 13 denotes a preliminary diffusion plate, which has an appropriate interval on the upstream side of the diffusion plate 5, and has a curing agent supply pipe 7 and a main agent supply pipe 1.
It is interposed between 1 and 1.

A second resin passage hole 14 is formed on the surface of the preliminary diffusion plate 13 at a position that does not align with the first resin passage hole on the surface of the diffusion plate 5.

Note that the other components are the same as those indicated by the same reference numerals in FIGS. 1 to 3.

In the above configuration, when the base agent flowing through the base agent supply pipe 11 reaches the preliminary diffusion plate 13, a part of it passes through the resin passage hole 14, but most of it passes through the third non-porous hole between the second resin passage hole 14. The liquid collides with the part, where it reverses and flows backward, causing a delay in transport time.

The main agent that has passed through the resin passage holes 14 then reaches the diffusion plate 5 and collides with the second non-porous area between the passage holes 6, and in the same manner as the preliminary diffusion plate 13, the main agent also reaches the diffusion plate 5. A transfer delay time is given to the base agent.

On the other hand, the effect of the transfer delay time given to the curing agent from the curing agent supply pipe 7 is the same as in the embodiment shown in FIGS. 1 to 3 described above.

In this way, the main agent directly passing through the resin passage holes 14 of the preliminary diffusion plate 13 collides with the second non-porous area between the resin passage holes 6 of the diffusion plate 5 and reverses and flows back, so that the transfer delay time is increased during this time. The hardening agent supplied from the hardening agent supply pipe 70 and the hardening agent from the dividing hole 8 is preliminarily mixed.

Therefore, the base resin does not directly and linearly pass through the resin passage holes 6 of the diffusion plate 5, and all the base resins are given a transfer delay time, making premixing with the curing agent effective. Become.

It should be noted that the number of preliminary diffusion plates is not limited to one, and a plurality of plates can be arranged as required. In this case, it goes without saying that the resin passage holes are formed at different positions from each other.

As described above, according to the present invention, in the injection molding machine for liquid resin that includes a static mixer inside the mixing cylinder, in the base material supply pipe extending upstream of the mixing cylinder,
A diffusion plate having resin passage holes is provided, and a curing agent supply pipe having a split hole at its tip is brought into contact with a first non-porous portion on the surface of the diffusion plate. With this configuration, the base agent supplied into the mixing cylinder collides with the second non-porous part between the resin passage holes of the diffusion plate, reverses and flows backward, detours, and then heads toward the resin passage holes, During this time, a transfer delay time occurs.

On the other hand, the curing agent supplied from the curing agent supply pipe collides with the first non-porous part on the surface of the diffusion plate, is divided by the dividing holes, flows outward, and then heads toward the resin passage hole. During this time, a transfer delay time occurs like the main agent.

During this transfer delay time, the base agent and curing agent collide with each other, causing disturbance and being effectively premixed, which is an excellent feature that completely eliminates the uneven mixing caused by the supply pump, etc. during supply, and can be introduced into the subsequent static mixer. effective.

In particular, according to a second invention related to the present invention, there is provided a preliminary diffusion plate in which a second resin passage hole is formed on the upstream side of the diffusion plate at a position that does not align with the first resin passage hole of the diffusion plate. is provided, it is possible to prevent the base agent from directly passing through the first resin passage hole of the diffusion plate, and the base agent that has passed through the second resin passage hole of the preliminary diffusion plate is prevented from passing through the second resin passage hole of the diffusion plate. There is an effect that premixing with the curing agent introduced in portions from the curing agent supply pipe is performed more effectively while the curing agent collides with the hole and reverses and flows back.

Furthermore, since the split holes of the curing agent supply pipe are each open to the second non-porous area between the first resin passing holes on the surface of the diffusion plate, the curing agent flowing outward from the split holes is absorbed into the second hole. Since the resin does not flow through one resin passage hole in a short-circuit manner, retention near the diffusion plate can be realized more effectively, and the above-mentioned mixing effect can be further improved.

Furthermore, according to the first and second inventions, the structure of the diffusion section that controls premixing does not have any movable parts, and the characteristic feature inherent in a static mixer type injection molding machine, namely, the movable Since there are no parts, the structure is simple, there are few failures, and maintenance is easy.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a perspective sectional view of one embodiment of the invention, and FIG. 2 is taken along the line A-A in FIG.
[I-plane view, Figure 3 is a BB sectional view of Figure 2,
The figure is a perspective sectional view of an embodiment of the second invention related to this invention, and FIG. 5 is a sectional view of the main part of FIG. 4. 1... Mixing tube, 3... Static mixer, 4... Diffusion section, 5... Diffusion plate, 6... Resin passage. 1-L7...Curing agent supply pipe, 8...Division hole, 11...Main agent supply pipe, 13...Preliminary diffusion plate, 14...・
...Resin passage hole.

Claims (1)

[Scope of Claims] 1. In an injection molding machine for liquid resin equipped with a static mixer 3 in a mixing cylinder 1, a diffusion part 4 is attached to the upstream side of the mixing cylinder 1, and the diffusion part 4 is provided with a static mixer 3 in a mixing cylinder 1. A diffusion plate 5, which is disposed in a main agent supply pipe 11 extending on the upstream side of the mixing cylinder 1 so that the axes thereof are common, and has a resin passage hole 6 bored on its surface, and the diffusion plate The resin passing hole on the surface of the diffusion plate 5 is arranged concentrically within the base agent supply pipe 11 so that its tip abuts against the first non-porous part on the surface of the diffusion plate 5. an injection molding machine for liquid resin, characterized in that it comprises a hardening agent supply pipe 7 in which a dividing hole 8 is bored so as to face a second non-porous part between the two parts. 2 In an injection molding machine for liquid resin equipped with a static mixer 3 in the mixing cylinder 1, a diffusion part 4 is attached to the upstream side of the mixing cylinder 1, and the diffusion part 4 is attached to the upstream side of the mixing cylinder 1. A diffusion plate 5 having a first resin passage hole 6 formed on the surface thereof is disposed in a base agent supply pipe 11 extending to The base agent supply pipe 1 is inserted so that its tip is in contact with the first non-porous part of the base material supply pipe 1.
1, and a dividing hole 8 is bored at the tip thereof so as to face a second non-porous area between the first resin passage holes 6 on the surface of the diffusion plate 5. A second resin is disposed on the upstream side of the curing agent supply pipe 7 and the diffusion plate 5 so that their axes are common, and a second resin is disposed on the surface of the diffusion plate 5 at a position that is not aligned with the first resin passage hole 6. Preliminary diffusion plate 1 with passage holes 14 drilled therein
3. An injection molding machine for liquid resin characterized by comprising: