JP3515245B2 - Screw temperature control device for injection molding machine - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a screw temperature controller for an injection molding machine.

[0002]

2. Description of the Related Art The temperature of an injection screw in an injection molding machine has a great influence on the resin conveying action and the heat history of the resin in the measuring process.

In particular, in the process of conveying resin for weighing,
By utilizing the difference between the frictional resistance acting between the resin and the outer peripheral surface of the injection screw and the frictional resistance acting between the resin and the inner peripheral surface of the injection cylinder, the rotation of the injection screw causes the resin to reach the tip side of the injection cylinder. I am trying to lead, but at this time,
In order to properly convey the resin, the temperature of the injection screw is adjusted so that the frictional resistance between the injection screw outer peripheral surface and the resin is smaller than the frictional resistance between the injection cylinder inner peripheral surface and the resin, It is necessary to prevent the resin from adhering to the outer peripheral surface of the injection screw.

This is because if the molten resin adheres to the outer peripheral surface of the injection screw and rotates together with the injection screw, the action of conveying the resin in the axial direction of the screw is hindered. To prevent this, At least on the base side of the injection cylinder, it is desirable that the temperature of the injection screw is relatively lower than the temperature of the injection cylinder.

In order to meet such a demand, a temperature adjusting means for adjusting the temperature of the injection screw should be provided. However, a drive mechanism of the injection screw that performs both rotation and linear movement in the axial direction, and its driving mechanism. Due to the complicated structure of the attachment part, it has been considered very difficult to attach the temperature control means to the injection screw itself.

Therefore, the temperature control of the injection screw, in particular, its cooling action is due to natural heat dissipation from the injection screw mounting portion,
Also, the natural heat dissipation effect by heat conduction to the resin pellets carried in from the resin sampling port of the injection cylinder and contacting the injection screw was used, but this is not always sufficient, and the resin pellets carried in from the resin sampling port are not necessarily sufficient. In some cases, the resin itself melts and a bridge or the like is generated in the vicinity of the resin sampling port, which hinders the resin pellet loading operation itself due to the rotation of the injection screw.

In such a case, in order to prevent inadvertent melting of the resin pellets, a water jacket for temperature control of the cylinder base provided on the outer peripheral portion of the resin sampling port is driven to strengthen the circumference of the resin sampling port. Although there is nothing but cooling, the base of the injection cylinder is also cooled at the same time, which is extremely disadvantageous when it is desired to perform the injection molding operation while keeping the injection cylinder base at a high temperature. Further, such a cooling operation causes the injection cylinder to be cooled earlier than the injection screw at the base of the injection cylinder, so even if the bridge itself is eliminated, the relative high temperature of the injection screw As a result, the resin adheres to the outer peripheral surface of the injection screw and rotates integrally with the injection screw, which may cause a problem that the action of conveying the resin in the axial direction of the screw is hindered.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned drawbacks of the prior art, to control the temperature of the injection screw independently of the temperature of the injection cylinder base, and to convey the resin during measurement and An object of the present invention is to provide a screw temperature control device for an injection molding machine that can easily manage the heat history of the resin.

[0009]

A screw temperature control device for an injection molding machine according to the present invention has a water jacket for temperature control of a cylinder base provided on an outer peripheral portion of a resin sampling port of an injection cylinder, and is provided behind the water jacket. , The injection screw configured by being divided into two in the injection axis direction
A water jacket for temperature control is placed on each divided surface.
Centering around the holes that fit with the outer peripheral surface of the base of the injection screw
Has a radius of curvature slightly larger than the injection screw diameter
Forming a semi-circular groove with an arc-shaped bend
The above object has been achieved by a constitution characterized in that a liquid guiding tube is closely arranged between the semi-circular grooves .

[0010] sheet by a dedicated water jacket used to deploy separately for Linda base water jacket and independently injection screw for temperature control of the temperature control, the injection screw independently of the temperature of the injection cylinder base temperature Is controlled to manage the transfer of the resin and the heat history of the resin during measurement. The water jacket for adjusting the temperature of the injection screw has a hole that fits with the outer peripheral surface of the base of the injection screw, allows rotation of the injection screw and linear movement in the axial direction, and removes heat from the outer peripheral surface of the base of the injection screw. cool the injection screw Te.

It is desirable that the pipe provided in the water jacket for adjusting the temperature of the injection screw is arranged in an annular shape so as to be close to the injection screw and surround the same in view of the efficiency of absorbing heat. As means for forming a conduit in a block-shaped member forming a water jacket, a plurality of drill holes are formed in the same cross-section of the block-shaped member so as to intersect with each other to block unnecessary openings. Method of forming a series of pipelines by
No. 58, etc.) is known, but in such a method, since the path of the formed conduit has a polygonal shape, there is a conduit portion that passes through a position considerably separated from the outer peripheral surface of the injection screw. As a result, the heat absorption efficiency may be disadvantageous.

Therefore, in the present invention, a water jacket for adjusting the temperature of the injection screw is further divided into two parts in the injection axis direction, and each divided surface has a diameter slightly smaller than the diameter of the injection screw with the hole as the center. A semi-arcuate groove having an arcuate bent portion having a large radius of curvature is formed, and a liquid guiding tube is closely arranged between opposing semi-arcuate grooves, thereby providing a direct proximity to the injection screw, and The pipe for flowing the temperature control liquid was arranged so as to surround this in an annular shape. According to this configuration, many parts of the pipeline through which the temperature control liquid flows are located in the vicinity of the outer peripheral surface of the injection screw, so that when the pipeline is arranged in a polygonal shape around the outer peripheral surface of the injection screw. compared, Ru can increase heat absorption efficiency.

By providing heat insulating means between the base of the injection cylinder and the water jacket for adjusting the temperature of the injection screw, mutual interference between the temperature of the base of the injection cylinder and the temperature of the water jacket for adjusting the injection screw is eliminated. The temperature of the injection screw can be easily controlled independently .

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing a main part of a screw temperature controller according to one embodiment, and FIG.
FIG. 3 is a cross-sectional view taken along line AA of FIG. The base of the injection cylinder 1 is provided with a resin sampling port 2 for loading resin pellets into the injection cylinder 1, and the base of the injection cylinder 1 and the lower part of the hopper 3 are located at positions corresponding to the positions where the resin sampling port 2 is drilled. A water jacket 4 for controlling the cylinder base temperature for cooling is attached.

The water jacket 4 is provided with a pipe line 5 for flowing the temperature control liquid and a communication port 6 for guiding the resin pellets stored in the hopper 3 to the resin sampling port 2. Is the same as a water jacket for cylinder base temperature control that is generally known in the past.

The water jacket 4 is fixed to a front surface of a front plate of an injection unit (not shown) integrally with the injection cylinder 1 by a bolt 8 inserted from a flange portion 7 of the injection cylinder 1, and projects rearward from the water jacket 4. The portion of the injection cylinder 1 that is present is accommodated in a hole formed in the center of the front plate. Also,
Injection screw 9 protruding from the base side of the injection cylinder 1
Is connected to the screw pusher plate of the injection unit via a screw rotation mechanism (not shown), the rotation of the injection screw 9 is performed by driving the screw rotation mechanism, and the injection mechanism fixed to the injection unit is used for injection. The injection screw 9 is driven in response to the forward and backward movement of the screw pusher plate driven along the shaft.
Is designed to move in the injection axis direction.

Regarding the structure on the injection unit side, Japanese Patent Application No.
-33333 and the like have already been explained in detail, so the explanation is omitted here.

The main part of the screw temperature adjusting device in this embodiment is composed of a water jacket 13 for adjusting the temperature of the injection screw, which is composed of cylindrical dividing members 10 and 11 and a liquid guiding tube 12.

Screw through holes 14 and 15 are formed in the center of each of the split members 10 and 11 so as to be in contact with the base of the injection screw 9, and holes are formed in the opposing surfaces of each of the split members 10 and 11. Arc-shaped bent portion 1 having a radius of curvature slightly larger than the diameter of the injection screw 9 around 14 and 15
Semi-circular grooves 18 and 19 provided with 6 and (17) are engraved. Although FIG. 2 shows only the semi-circular groove 18 on the side of the dividing member 10 and the arc-shaped bent portion 16 included in the groove 18, the semi-circular groove 1 on the side of the dividing member 11 is shown.
The same applies to 9 and its arcuate bent portion (17).

Further, the circular pipe-shaped liquid guiding tube 12 is bent in a U-shape as shown in FIG. 2, and is formed in a semi-circular groove 18, 19 when the dividing members 10, 11 are joined. It is designed so that it can be attached closely to the space.

The liquid guide tube 12 is formed of a round pipe in addition to the dividing members 10 and 11 in order to enhance the durability of the water jacket 13 and to divide the dividing members 10 and 11.
This is to prevent the temperature control liquid from leaking from the joint surface of. If the joint surface of the dividing members 10 and 11 is provided with a sealing material or is filled with a sealing material, the liquid guiding tube 12 is not necessarily required, and the U-shaped groove formed by the semi-circular grooves 18 and 19 is formed. The space itself can be used as a conduit for flowing the temperature control liquid. Since the sealant and the sealant are generally formed of a non-metallic material, there is some concern about heat resistance and aging. In this embodiment, the sealant and the sealant are used to improve durability. Instead of using the sealant, the liquid guiding tube 12 is merely embedded in the U-shaped space formed by the semi-circular grooves 18 and 19. In order to improve the efficiency of heat conduction, the liquid guide tube 12 needs to be placed so as to be completely in close contact with the semicircular grooves 18, 19.

The semi-circular grooves 18 and 19 are provided with the arc-shaped bent portions 16 and (17).
This is because the pipe line formed by the liquid guide pipes 8 and 19 is disposed as close to the outer peripheral surface of the base portion of the injection screw 9 as possible to improve the heat discharging effect of the temperature control liquid. Therefore, it is clear that the higher the ratio of the arcuate bent portions 16, (17) close to the outer peripheral surface of the base of the injection screw 9 to the entire pipeline, the more advantageous in terms of the cooling effect. If the grooves 18 and 19 and the liquid guiding tube 12 are formed in the shape of Ω as a whole so as to increase the portion of the arcuate bent portions 16 and (17) that are in close contact with the outer peripheral surface of the base portion of the injection screw 9, It is possible to further enhance the cooling effect.

Although it depends on the shape of the conduit formed by the semi-circular grooves 18 and 19, the dividing members 10 and 11 may be formed as a complete integral molding by casting and the nesting portion may be removed by post-processing to form a circle. It is possible to form a conduit having an arcuate bend. Of course, in this case, the sealing material, the sealing material, and the liquid guiding tube 12 are unnecessary.

As shown in FIG. 1, the water jacket 13 for adjusting the temperature of the injection screw, which is formed by sandwiching the liquid guiding tube 12 between the divided members 10 and 11, is a bolt passed from the back side of the divided member 11. 20, the injection cylinder 1 is provided behind the water jacket 4 for controlling the temperature of the cylinder base.
Is integrally fixed to the end of the. In addition, a thin heat insulating material 21 made of asbestos or the like is provided at the joint between the water jacket 13 and the injection cylinder 9 so that the base temperature of the injection cylinder 9 and the temperature of the water jacket 13 do not directly interfere with each other. Has become. The cross-sectional shape of the heat insulating material 21, except that the semi-circular arc-shaped groove 18 is not provided,
The sectional shape of the split member 10 shown in FIG. 2 is exactly the same.

In this embodiment, the injection cylinder 1
Outer diameter and water jacket 13 (split members 10, 1
Since the outer diameter of 1) is exactly the same, it was drilled in the center of the front plate including the water jacket 13 as well as the portion of the injection cylinder 1 projecting rearward from the water jacket 4. Can be stored in the mounting hole. Since it is necessary to connect both ends of the liquid guiding pipe 12 provided in the water jacket 4 to a temperature control liquid circulating device or the like via a hose or the like, a cutout portion is provided in the mounting hole at the center of the front plate to connect the hose. It is necessary to change the design so that

Further, in FIG. 1, the water jacket 13
Although an example in which a heat insulating material 21 made of a different material is interposed at the joint between the injection cylinder 9 and the injection cylinder 9, the end surface of the water jacket 13 (the dividing member 10) and the end surface of the injection cylinder 1 have extremely rough surface roughness. If the mutual contact area is reduced as a finish, a certain degree of heat insulating effect can be expected. As a matter of course, a further heat insulating effect can be expected by positively performing groove processing with a fine pitch or the like on the mutual end faces or one of the end faces.

If a suitable flange portion is formed on the water jacket 13 (split member 10), the water jacket 13 can be attached to the rear end portion of the water jacket 4 for controlling the cylinder base temperature. In this case, A heat insulating means is provided between the flange portion of the water jacket 13 (divided member 10) and the rear end portion of the water jacket 4. Even if the water jacket 13 is attached to the water jacket 4, if the main body of the water jacket 13 directly contacts the rear end surface of the injection cylinder 1, the rear end surface of the injection cylinder 1 and the main body of the water jacket 13. It is necessary to provide a heat insulating means between and.

Further, the water jacket 13 can be attached to the front plate side of the injection unit, and in this case, if there is a certain gap between the water jacket 4 and the injection cylinder 1 and the water jacket 13, the heat insulating means. Is not necessary.

Since the base of the injection cylinder 1 and the lower part of the hopper 3 can be controlled independently by the water jacket 4 and the base temperature of the injection screw 9 can be independently controlled by the water jacket 13, the base temperature of the injection cylinder 1 can be controlled. While maintaining the temperature suitable for the injection molding operation, the base temperature of the injection screw 9 is relatively lowered to ensure the conveyance of the resin at the time of measurement, and the thermal history of the residence time of the resin in the cylinder is kept constant. It becomes easy to hold the resin at a high temperature, and it is possible to prevent molding abnormalities due to abnormal plasticization of the resin or defective measurement.

Further, like a conventional water jacket structure, a polygonal shape (generally a rectangular shape) in which drill holes are continuously provided.
The pipe line may be formed so as to surround the heat source with the pipe line and carry out the heat of the heat source. However, as described above, the water jacket 1 having the arcuate bent portions 16 and (17).
According to the pipe line configuration of 3, since the temperature control liquid can be flown along the position immediately adjacent to the outer peripheral surface of the base of the injection screw 9,
Compared to the conventional water jacket structure in which the refraction part of the conduit is largely separated from the heat source, the heat transfer efficiency is good, and the temperature control effect of the water jacket itself is excellent. Therefore, as long as the manufacturing cost and the like allow, the pipe configuration of the water jacket 13 as disclosed in FIG. 1 and FIG.
May also be applied to.

[0031]

As described above, in the screw temperature control device of the present invention, a water jacket for controlling the temperature of the cylinder base portion is provided independently of the water jacket for controlling the temperature of the injection screw. The temperature of the injection screw can be controlled independently of the temperature of the cylinder base. Therefore, while maintaining the base temperature of the injection cylinder at a temperature suitable for the injection molding operation, the base temperature of the injection screw is relatively lowered to ensure the transfer of the resin at the time of measurement, and the residence time of the resin in the cylinder. It is also easy to keep the heat history of No. 1 under a constant condition, and it is possible to prevent molding abnormalities due to plasticization abnormalities of resins, defective measurement, and the like.

Moreover, the water jacket pipe for adjusting the temperature of the injection screw is provided with an arcuate bent portion having a radius of curvature slightly larger than the diameter of the injection screw so as to surround the injection screw in an annular shape, and Since the temperature control liquid can be flown in the immediate vicinity of the injection hole, the temperature control liquid can be heated in comparison with the conventional water jacket structure in which a polygonal pipe line is arranged around the outer peripheral surface of the injection screw by connecting drill holes. The adjusting function itself is excellent, and the temperature of the injection screw can be controlled more effectively.

Further, since the heat insulating means is provided between the base of the injection cylinder and the water jacket for adjusting the temperature of the injection screw, the temperature of the base of the injection cylinder and the temperature of the water jacket for adjusting the temperature of the injection screw are mutually dependent. The interference can be eliminated and the temperature of the injection screw can be easily controlled independently.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a main part of a screw temperature controller according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a portion AA in FIG.

[Explanation of symbols]

1 injection cylinder 2 Resin sampling port 3 hoppers 4 Water jacket for cylinder base temperature control 5 pipelines 6 connection 7 Flange 8 volt 9 injection screw 10 split members 11 split members 12 Liquid pipe 13 Water jacket for injection screw temperature control 14 Screw through hole 15 Screw through hole 16, (17) Arc-shaped bend 18, 19 semi-circular groove 20 volts 21 thermal insulation

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Ishiguro 3580 Koshinoba, Oshinomura, Minamitsuru-gun, Yamanashi Prefecture FANUC Co., Ltd. (72) Inventor Tatsuya Kawasaki 3580 Kobaba, Oshinomura, Minamitsuru-gun, Yamanashi Prefecture FANUC Incorporated (56) References: Fukuihei 4-13310 (JP, U) Fukuikaihei 2-58924 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B29C 45/74 B29C 45/78

Claims (2)

(57) [Claims] 1. A water jacket for temperature control of a cylinder base is provided on an outer peripheral portion of a resin sampling port in an injection cylinder, and an injection is performed behind the water jacket.
For injection screw temperature control, which is configured by dividing into two in the axial direction.
Place a water jacket and shoot on each of the divided surfaces.
The injection stroke is centered on the hole that fits the outer peripheral surface of the base of the exit screw.
An arc shape with a radius of curvature slightly larger than the clew diameter
Forming a semi-circular groove with a bent portion, facing a semi-circular shape
A screw temperature controller for an injection molding machine, in which a liquid guiding tube is closely arranged between the grooves . 2. A heat insulating means is provided between the base of the injection cylinder and the water jacket for adjusting the temperature of the injection screw,
The water jacket for adjusting the temperature of the injection screw, which has the same outer diameter as the outer diameter of the injection cylinder, is integrally fixed to the base of the injection cylinder via the heat insulating means.
1 Symbol mounting screw temperature control device for an injection molding machine.