JP2003200474A - Tip nozzle and adapter of injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tip nozzle and an adapter of an injection molding machine, which show high general-purpose properties and an enhanced temperature measuring precision. <P>SOLUTION: The tip nozzle 1 is of an attachable/detachable tip type that it is fitted into the adapter 2 by screwing a male thread part 9a of the tip nozzle 1 into a female thread part 9b of the adapter 2. In addition, a first groove 8a for a thermocouple for mounting a first thermocouple 4a so that a first measurement point 7a is positioned within a first coating region 10a covered on a first heater 3a fitted to the outer periphery of the tip nozzle 1, is formed on the tip nozzle 1. The first thermocouple 4a is hardly influenced by an open air temperature, since the first measurement point 7a is positioned within the first covering region 10a. Consequently, the heat conducted from the first heater 3a to a first resin passage 12a can be highly precisely measured. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tip nozzle and an adapter for an injection molding machine equipped with a thermocouple for controlling the temperature by a heater.

[0002]

2. Description of the Related Art Injection molding generally includes a mold closing process of closing a mold, a mold clamping process of clamping the mold, a nozzle touch process of pressing a nozzle against a sprue of the mold, and a screw in a cylinder being advanced. The injection process of injecting the molten resin accumulated in the front of the screw into the mold, the pressure holding process of applying a holding pressure for a while to suppress the generation of bubbles and sink marks, and the resin filled in the mold For the next cycle in the time between cooling and solidifying, the screw is rotated and the plasticizing process that accumulates the molten resin in front of the cylinder while melting the resin and the molten resin accumulated at the nozzle tip The injection device retracting step of retracting the injection device so that it is not cooled and solidified by the mold, and in order to take out the solidified molded product from the mold, the mold is opened and the molded product is provided with a protruding pin. Consisting of a mold opening-molded article ejection extruding by.

When the above steps are repeated, the resin melted in the cylinder is sent through the nozzle to the mold in this injection operation, and then filled, and then the resin in the nozzle located between the mold and the cylinder is filled. Will be sent to the mold at the next injection. Therefore, the resin remaining in the nozzle needs to be managed in an optimal state for filling the mold, and the heater is turned on and off based on the temperature detected by a temperature sensor such as a thermocouple.
The temperature is controlled by FF.

FIG. 4 is a side sectional view of a nozzle portion of a conventional injection molding machine.

The tip nozzle 101 of the nozzle portion of the injection molding machine shown in FIG. 4 is screwed into the joint portion 106 of the adapter 102 and is attachable to and detachable from the adapter 102. That is, by exchanging only the tip nozzle 101, the R shape of the tip is changed according to the mold (not shown), or the injection port 106 is changed according to the resin material used.
The diameter can be changed easily.

The cylinder 105 is internally provided with a screw (not shown) for plasticizing the resin raw material from a hopper (not shown) for accommodating the resin raw material forward (to the left in FIG. 4). .

The tip nozzle 101 has a first outer peripheral surface for heating the resin raw material supplied from the cylinder 105.
Heater 103a is attached, and a first thermocouple 104a is provided for temperature control of the resin raw material in the first resin passage 107a that is heated and melted by the first heater 103a. This first thermocouple 104
The temperature measurement point 104a ′ according to a is the first heater 10
It is located outside the covered area 110 of 3a (in FIG. 4, the shaded area).

The adapter 102 is also provided with a second heater 103b and a second thermocouple 104b. The second thermocouple 104b is connected to the second heater 10
This is for controlling the temperature of the resin raw material in the second resin passage 107b that has been heated and melted by 3b.

The resin raw material supplied from the cylinder 105 to the nozzle portion is heated and melted by the second heater 103b and the first heater 103a while being heated and melted by the second resin passage 10.
7b and the first resin passage 107a through the injection port 106
Is injected into the mold from.

FIG. 5 shows a side sectional view of a nozzle portion of another conventional injection molding machine.

The nozzle 208 of the injection molding machine shown in FIG.
The tip nozzle and the adapter are integrally formed.

The nozzle 208 also includes first and second heaters 203a and 203b, and first and second thermocouples 204.
a and 204b are provided. In the case of this integrally formed nozzle, the R shape of the tip is changed depending on the mold, or the injection port 1 is changed according to the resin raw material used.
Since it is necessary to replace the nozzle 208 itself in order to change the diameter of 06, it is less versatile than the separation type nozzle shown in FIG. 4, but for the thermocouple for the first thermocouple 204a. The tip of the groove 206, that is, the first thermocouple 2
The temperature measurement point 204 ′ by 04 a is the first heater 20.
Since it is located in the covering region 210 (shaded portion in FIG. 5) of 3a, it is possible to measure the temperature with high accuracy in a state where it is hardly affected by the outside air temperature.

In any of the injection molding machines having the above configurations, the control means (not shown) turns on the heater based on the temperature detected by the thermocouple.
The configuration is such that the temperature of the resin in the nozzle portion is controlled by turning off and on.

[0014]

As described above, as shown in FIG.
Although the separation type nozzle shown in Fig. 5 has high versatility, it cannot be said that the accuracy of the temperature measurement of the nozzle part is sufficient because it is affected by the outside temperature. On the other hand, in the case of the integrated type nozzle shown in Fig. Since the temperature of the nozzle portion can be accurately measured because it is not easily affected by, the general versatility tends to be low.

Therefore, as a nozzle having high versatility and high temperature measurement accuracy, as shown in FIG.
The tip nozzle 30 in which the first groove 306a is formed so that the measurement point 304 is in the covering region 310 of the first heater 303.
1 and a second groove 306b connected to the first groove 306a
A nozzle having a configuration with the adapter 302 in which is formed is conceivable.

However, since the tip nozzle 301 is screwed into the joint portion 305 of the adapter 302, the tip nozzle 301 is screwed into the joint portion 305 of the adapter 302 as shown in FIG. When assembling by screwing into the adapter 302, the first groove 306a and the second groove 3
The position in the circumferential direction with respect to 06b is displaced, and there is a concern that the thermocouple cannot be attached.

Therefore, it is an object of the present invention to provide a tip nozzle and an adapter for an injection molding machine, which are highly versatile and have improved temperature measurement accuracy.

[0018]

In order to achieve the above object, a tip nozzle of an injection molding machine according to the present invention has a female screw portion (9b) of an adapter (2, 22) held at an end portion of a cylinder (5). , 29b) to be screwed into the male screw portion (9
a, 29a) is formed on one end side and the first heater (3
a, 23a) on the outer periphery of the tip nozzle (1, 21) of the injection molding machine, the first thermocouple (4a, 24)
The first measurement point (7a, at which the temperature is measured according to a)
27a) is located in the first coating region (10a, 30a) covered by the first heater (3a, 23a) so that the first thermocouple (4a, 24a)
The thermocouple groove (8, 28a) for attaching the is formed.

In the tip nozzle of the injection molding machine of the present invention constructed as described above, the thermocouple groove is formed so that the measurement point of the thermocouple is located within the coating region covered by the heater. As a result, the thermocouple attached to the tip nozzle is less likely to be affected by the outside temperature,
It enables highly accurate temperature measurement.

Further, in the tip nozzle of the present invention, when the male screw parts (9a, 29a) are screwed into the female screw parts (9b, 29b) of the adapters (2, 22), the adapters (2, 2).
2) and the tip nozzle (1, 21), the escape (11, 31) of the lead-out portion (4a ', 24a') of the first thermocouple (4a, 24a) is formed. Good. As a result, even in a tip nozzle that is screwed and fixed to the adapter, it is possible to perform temperature measurement in a state in which the thermocouple does not interfere with the adapter and is hardly affected by the outside air temperature. Further, the heat insulating ring (26) may be arranged in the escape (31). In this case, the heat insulating ring provides a heat insulating measure against the adapter and the outside air, which enables more accurate temperature measurement.

The adapter of the present invention is an adapter to which the tip nozzle (1, 21) of the present invention can be attached, and the second measurement point (27b) at which the temperature is measured by the second thermocouple (24b). ) Is located in a second coating region (29b) covered by a second heater (23b) mounted on the outer circumference of the adapter (22), the second thermocouple (24b) Is formed with a second thermocouple groove (28b) for mounting.

In the adapter of the present invention, the thermocouple groove is formed so that the measurement point of the thermocouple is located within the coating region covered by the heater. As a result, the thermocouple attached to the adapter becomes less susceptible to the influence of the outside air temperature together with the tip nozzle, and thus highly accurate temperature measurement becomes possible.

Further, in the injection molding machine using the above-described tip nozzle and adapter of the present invention, the nozzle heater control section controls the temperature of the nozzle section on the basis of the temperature accurately measured in a state where it is hardly affected by the outside air temperature. Therefore, highly accurate temperature control can be performed. Further, since this injection molding machine has the tip nozzle screwed into the adapter, that is, has a detachable structure, the R shape of the nozzle tip is changed according to the mold, and the resin raw material to be used is changed. Further, the injection molding machine with high versatility can easily perform the change of the diameter of the injection port and the like by exchanging only the tip nozzle without exchanging the whole nozzle portion.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. (First Embodiment) FIG. 1 schematically shows the overall construction of an example of an injection molding machine equipped with the tip nozzle of the present invention.

The injection molding machine shown in FIG. 1 has a hopper 51 for containing a resin material, a cylinder 5 to which the resin material is supplied from the hopper 51, and a resin material supplied to the inside of the cylinder 5 (see FIG. 1). , A screw 57 for plasticizing while sending it to the left), a heater (not shown) for heating the resin raw material in the cylinder 5, the tip nozzle 1 attached to the front end of the cylinder 5, and Based on the measured temperature detected by the nozzle portion 13 having the adapter 2 and the first and second thermocouples 3a, 3b,
A nozzle heater control unit 60 that controls ON and OFF of the first and second heaters 4a and 4b, a bearing unit 53 that rotatably supports the screw 57 about its axis, and a screw 57 that rotates about that axis. Driving means 54 for driving
And a ball screw mechanism part 55 assembled to the bearing part 53.
And the ball screw mechanism 55 to drive the bearing 53.
Drive means 5 connected to the ball screw mechanism section 55 via a timing belt 58 for moving in the front-back direction.
6 and 6, respectively.

The hopper 51 contains the resin material to be supplied into the cylinder 5, and the cylinder 5 holds the screw 57 rotatably and axially slidably therein. The nozzle portion 13 is for injecting a resin material melted by a heater attached to the cylinder 5 and plasticized by the screw 57 into a mold (not shown). Details of the nozzle unit 13 will be described later.

The screw 57 has its end portion (right end portion in FIG. 1) rotatably supported by the bearing portion 53, and is connected to the driving means 54. Drive means 54
As a result, the screw 57 is rotationally driven, and the resin raw material is sent forward while being plasticized. Further, a backflow prevention ring 59 is incorporated on the tip side of the screw 57, so that the molten resin does not flow back to the rear side of the screw 57 at the time of injection.

The drive means 54, 56 may be servomotors or hydraulic motors.

Next, FIG. 2 shows an enlarged side sectional view of a part of the nozzle portion of the injection molding machine in this embodiment.

As described above, the nozzle portion 13 of this embodiment includes the tip nozzle 1 in which the injection port 6 for injecting the molten resin is formed, and the adapter 2 for mounting the tip nozzle 1 in the cylinder 5. Have. The tip nozzle 1 is
The male threaded portion 9a of the tip nozzle 1 is screwed into the female threaded portion 9b of the adapter 2 to be mounted on the adapter 2. That is, since the tip nozzle 1 is a tip type nozzle that can be attached to and detached from the adapter 2, the R shape of the nozzle tip is changed according to the mold (not shown), and the injection port 6 according to the resin material used. The diameter of the nozzle can be changed easily by replacing only the tip nozzle 1 without replacing the entire nozzle portion 13.

The tip nozzle 1 has a cylinder 5 on its outer circumference.
A first heater 3a for heating and melting the resin raw material supplied from is attached. Also, the tip nozzle 1
Has a first resin passage 12a communicating with the injection port 6 formed on the side abutting the mold, and a first coating region 10a coated with the first heater 3a. A first thermocouple groove 8a for mounting the first thermocouple 4a is formed so that the first measurement point 7a is located inside (hatched portion in FIG. 2). First thermocouple 4
Since the temperature a is measured at the first measurement point 7a which is less likely to be affected by the outside air temperature because it is located in the first coating region 10a, it is transmitted from the first heater 3a to the first resin passage 12a. Can measure heat accurately. The first measurement point 7
2, a is shown to be located approximately in the middle between the first resin passage 12a and the first heater 3a as viewed in the radial direction of the tip nozzle 1, but the present invention is not limited to this. Instead, the position may be changed as needed as long as it is within the first covered region 10a.

On the surface of the tip nozzle 1 facing the adapter 2, escape 11 so that the lead-out portion 4a 'of the first thermocouple 4a attached to the first thermocouple groove 8a does not interfere with the adapter 2. Are formed. By this escape 11,
Since there is no influence on the handling of the first thermocouple 4a, the tip nozzle 1 can be of a screw-in type that can be attached to and detached from the adapter 2.

The adapter 2 is also provided with a second heater 3b and a second thermocouple 4b. The second heater 3b is for heating the resin raw material in the second resin passage 12b communicating with the first resin passage 12a, and the second heater 3b for measuring the temperature at the second measurement point 8b. The thermocouple 4b is heated by the second heater 3b and melted.
This is for controlling the temperature of the resin raw material in the resin passage 12b. The adapter 2 is screwed and fixed to the cylinder 5.

The resin raw material supplied from the cylinder 5 to the nozzle portion 13 is the second heater 3b and the first heater 3a.
While being heated and melted, is injected into the mold from the injection port 6 through the second resin passage 12b and the first resin passage 12a.

The first thermocouple 4a and the second thermocouple 4b
The temperature detected by is transmitted to the nozzle heater control unit 60, and the nozzle heater control unit 60 detects the first temperature based on the detected temperature.
The heater 3a and the second heater 3b are turned on and off to control the temperature of the resin in the chip nozzle 1 and the adapter 2.

As described above, the injection molding machine of the present embodiment is accurate because the first measurement point 7a of the first thermocouple 4a is located within the first coating area 10a of the tip nozzle 1. Since high temperature measurement is performed and ON / OFF control of the first heater 3a is performed based on this measurement value, temperature control of the nozzle portion, which requires the most important temperature control in injection, can be performed with high accuracy. it can. Further, since the tip nozzle 1 of this embodiment is configured to be attachable to and detachable from the adapter 2, it has high versatility. (Second Embodiment) FIG. 3 is an enlarged side sectional view of a part of a nozzle portion of an injection molding machine according to this embodiment.

The nozzle portion 33 of this embodiment is shown in FIG.
As shown in FIG. 2, the second thermocouple groove 28b is provided on the adapter 22 so that the second measurement point 27b is located in the second covering region 30b of the second heater 23b, which is hardly affected by the outside air temperature. Is formed, and the male screw portion 29a of the tip nozzle 21 is screwed into the female screw portion 29b of the adapter 22 so that the tip nozzle 21 is held by the adapter 22 and the lead-out portion 24a ′ of the first thermocouple 24a. Relief 31 formed so that does not interfere with the adapter 22
3B, which is a sectional view of the tip nozzle 21 taken along the line AA ′ shown in FIG. 3A, the heat insulating ring 26 is provided around the step 41 of the tip nozzle 21. Since the nozzle portion 13 is basically the same as the nozzle portion 13 described in the first embodiment except that it is attached, detailed description thereof will be omitted.

For the temperature measurement at the tip nozzle 21, not only the first measurement point 27a is provided in the first covering region 30a of the first heater 3a, but also the tip nozzle 2
By mounting the heat insulating ring 26 around the stepped portion 41 of No. 1, it is possible to further reduce the influence of the outside air temperature on the heat insulation of the adapter 22 and the temperature measurement by the first thermocouple 24a, and it is possible to further improve accuracy. High temperature measurement is possible.

The material of the heat insulating ring 26 is preferably ceramic, glass wool, asbestos plate, etc., but is not limited to these.

The second thermocouple 24b also has a second coating area 3 of the second heater 23b which is hardly affected by the outside air temperature.
Since the temperature is measured at the second measurement point 27b located within 0b, the temperature can be measured with higher accuracy.

As described above, in the nozzle portion 33 of this embodiment, the tip nozzle 21 has the first measurement point 27a.
Is located in the first coating region 30a, and the adapter 22 and the first thermocouple 23a in which heat insulation measures against the outside air are performed by the heat insulating ring 26 provide accurate temperature measurement, and the adapter 22 However, since the second measurement point 27b is located in the second coating region 30b that is less likely to be affected by the outside air temperature, the second thermocouple 23b can measure the temperature with high accuracy. Therefore, in the injection molding machine of this embodiment, ON / OFF control of the first heater 23a and the second heater 23b is performed based on highly accurate measurement values, and the most important temperature control in injection is performed. The required temperature control of the nozzle portion can be performed with high accuracy. In addition, the tip nozzle 21 of the present embodiment
Also, like the tip nozzle 1 of the first embodiment, since it is configured to be attachable to and detachable from the adapter 22, it is highly versatile.

[0042]

As described above, according to the present invention, since the measuring points of the thermocouples of the tip nozzle and the adapter are covered by the heater, they are located in the covered area which is not easily affected by the outside air temperature. Therefore, it is possible to accurately measure the temperature by the thermocouple. And since the present invention controls the temperature of the nozzle portion based on a highly accurate measurement value,
Highly accurate temperature control can be performed. Furthermore, the present invention is highly versatile because the tip nozzle is attachable to and detachable from the adapter.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an overall configuration of an example of an injection molding machine equipped with a tip nozzle according to the present invention.

FIG. 2 is a side sectional view of a nozzle portion of the injection molding machine according to the first embodiment of the present invention.

FIG. 3 is a side sectional view of a nozzle portion of an injection molding machine according to a second embodiment of the present invention.

FIG. 4 is a side cross-sectional view of an example of a conventional separation type nozzle unit including a tip type nozzle and an adapter.

FIG. 5 is a side sectional view of an example of a conventional integrated nozzle unit.

6A and 6B are views for explaining groove misalignment that occurs when the thermocouple groove of the integrated nozzle section shown in FIG. 5 is formed in the separation type nozzle shown in FIG.

[Explanation of symbols]

1,21 tip nozzle 2.22 adapter 3a, 23a First heater 3b, 23b Second heater 4a, 24a First thermocouple 4a ', 24a' drawer part 4b, 24b Second thermocouple 5 cylinders 6 Exit 7 measurement points 8a, 28a First thermocouple groove 8b, 28b Second groove for thermocouple 9a, 29a Male thread part 9b, 29b Female thread 10a, 30a First coverage area 11, 31 escape 12a First resin passage 12b Second resin passage 13, 33 Nozzle part 26 Insulation ring 27a First measurement point 27b Second measurement point 28 Thermocouple groove 30b Second covering area 41 steps 51 hopper 53 Bearing 54, 56 drive means 55 Ball screw mechanism 57 screws 58 Timing Belt 59 Backflow prevention ring 60 Nozzle heater controller

Claims (4)

[Claims] 1. A male screw portion (9a, 29a) screwed into a female screw portion (9b, 29b) of an adapter (2, 22) held at an end portion of a cylinder (5) is formed at one end side, At the tip nozzle (1, 21) of the injection molding machine equipped with the first heater (3a, 23a) on the outer circumference, the first measurement point at which the temperature is measured by the first thermocouple (4a, 24a). (7a, 27a) is located in the first coating area (10a, 30a) covered by the first heater (3a, 23a), so that the first
1. A chip nozzle of an injection molding machine, characterized in that grooves (8a, 28a) for a thermocouple for mounting the thermocouples (4a, 24a) are formed. 2. The adapter (2, 22) and the tip nozzle (1) when the male thread (9a, 29a) is screwed into the female thread (9b, 29b) of the adapter (2, 22). , 21) between the first thermocouple (4
a, 24a) escape portion (4a ', 24a') escape (1
The tip nozzle of the injection molding machine according to claim 1, wherein the tip nozzle is shaped so that (1, 31) is formed. 3. Insulation ring (26) in said relief (31)
The tip nozzle of the injection molding machine according to claim 2, wherein 4. An adapter to which the tip nozzle (1, 21) according to any one of claims 1 to 3 can be attached, the temperature of which is measured by a second thermocouple (24b). The second measuring point (27b) is located in the second covering region (29b) covered by the second heater (23b) attached to the outer circumference of the adapter (22). A second thermocouple groove (28b) for attaching the thermocouple (24b) of claim 1 is formed.