JP2678960B2 - Cylinder assembly of injection unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection unit of an injection molding machine.

[0002]

2. Description of the Related Art A cylinder assembly 1 (FIG. 1) in an injection unit of an injection molding machine usually comprises a barrel 2, a nozzle adapter 3 and a nozzle 4, and the nozzle 4 is attached to the nozzle adapter 3 by screwing. 3 is fixed to the tip of the barrel 2 with a bolt 5. A screw 6 is inserted into the barrel 2 to knead, measure, and melt the resin introduced therein.

Heaters 7 (a to c) are attached to the barrel 2, the nozzle adapter 3 and the nozzle in order to accelerate the melting and to maintain the molten state of the resin. Further, temperature sensors 8 (a, b) such as thermocouples are arranged in the barrel 2 and the nozzle 4 in order to control the heating state by the heater 7, and these are provided in the temperature control device 9 for controlling the power supplied to the heater 7. It is connected. The temperature control device 9 is usually composed of a temperature control task-related part in a numerical control device (NC device) provided in the injection molding machine and a drive part for executing a command from the part.

In the cylinder assembly 1, the barrel
2. The temperature condition of each part of the nozzle adapter 3 and the nozzle 4 is important for obtaining a high quality molded product, and
Since it varies depending on the type of resin, the temperature is carefully controlled . However, as described above, in the conventional heater 7, for example, the heater 7a includes the outer peripheral surface of the barrel 2 and the nozzle adapter 3.
Or it is disposed over the outer peripheral surface of the large diameter portion of the heater
So that 7b covers the outer peripheral surface of the small diameter part of the nozzle adapter 3.
And the heater 7c covers the outer peripheral surface of the nozzle 4.
And the head of the bolt 5 of the nozzle adapter 3 projects.
The tool-engaging portion 10 in which the polygon of the front and the nozzle 4 of the large diameter portion which is not provided. Furthermore, the temperature sensor 8
Is provided only on barrel 2 and nozzle 4 , nozzle adapter
3 is not provided. For this, the head of the bolt 5
When the tool hook 10 of the nozzle 4 comes into contact with the surrounding air,
Heat is dissipated from the head of the gutter 5 and the tool hook 10 of the nozzle 4,
And it is "unevenness" in the resin temperature of Le adapter 3 and the nozzle 4, which may cause temperature portion deviated from the proper circumstances. In addition, the resin temperature inside the nozzle adapter 3 may not be detected , and the resin may be injected in that situation.
As a result, deterioration of the resin due to high temperature or generation of burrs due to excessive fluidity, or abnormal load of the screw 6 or short-circuiting of molded products caused by insufficient fluidity of resin at low temperature may occur.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cylinder assembly of an injection unit, which can maintain the internal resin temperature in an appropriate condition.

[0006]

The present invention relates to a cylinder assembly in which a nozzle is attached to the tip of a barrel through a nozzle adapter. The head of the bolt that secures the nozzle adapter to the barrel is sunk into a counterbore formed in the front of the large diameter portion of the nozzle adapter. Outer surface of barrel, nozzle
The outer peripheral surface of the large diameter part of the adapter and the gap between the large diameter part of the nozzle adapter
To cover these surfaces on the front surface facing the boring hole, the outer peripheral surface of the small diameter portion and the outer peripheral surface including the tool hanging portion of the nozzle, and
Barrel section is separated into the nozzle adapter portion and the nozzle portion heater is mounted, respectively. Barrel , no
A temperature sensor is attached to each of the nozzle adapter and the nozzle and is connected to the temperature control device.

[0007]

DETAILED DESCRIPTION A cylinder assembly 1 comprises a barrel 2, a nozzle adapter 3 and a nozzle 4. Nozzle adapter 3
The nozzle 4 is attached to the barrel 2 by screwing, and the nozzle adapter 3 is fixed to the barrel 2 by the bolt 5. Insertion of bolt 5 in front of large diameter part of nozzle adapter 3
A counterbore 11 is formed in the place. Thus, the bolt 5 for fixing against the nozzle adapter 3 in the barrel 2 head, as shown in FIG. 2, the large diameter portion of the nozzle adapter 3
It is sunk in the counterbore 11 formed on the front surface . Code 10
Is a tool hook and is formed integrally with the nozzle 4.

Heaters 7a (plurality) are attached to the barrel 2 so as to cover the outer peripheral surface thereof, and a thermocouple 8a as a temperature sensor is embedded in the barrel 2. A heater 7b and a heater 7d are attached to the nozzle adapter 3. The heater 7b is mounted so as to cover the outer peripheral surface of the large-diameter portion of the nozzle adapter 3, and the heater 7d has a front surface and a small surface facing the counterbore 11 of the large-diameter portion of the nozzle adapter 3 in cross section.
An annular brass member having a surface that covers the outer peripheral surface of the diameter portion.
The micro heater 12 is embedded so as to face the periphery of the outer peripheral surface . Heater 7d is fitted to the small diameter portion of the nozzle adapter 3 before screwing the nozzle 4 to the nozzle adapter 3, human
The end surface and the inner peripheral surface of the rotor 7d are the large diameter portion of the nozzle adapter 3.
The front surface facing the counterbore hole 11 and the outer peripheral surface of the small diameter portion are in close contact with each other. Further, a thermocouple 8b as a temperature sensor is attached to the nozzle adapter 3.

The nozzle 4 has a heater 7c and a heater 7e.
Is installed. The heater 7e is attached so as to cover the tool hanging portion 10 of the nozzle 4, and is configured to have a polygonal shape. The heater 7c is a tool for the nozzle 4
It is attached so as to cover the outer peripheral surface excluding the scale 10 . A thermocouple 8c as a temperature sensor is also attached to the nozzle 4. The thermocouples 8 (a to c) are each connected to a temperature control device 9 (not shown) as in the conventional example. As described above, the heater 7 (a to e) that heats the cylinder assembly 1 covers most of the outer surfaces of the barrel 2, the nozzle adapter 3, and the nozzle 4, and is separated at each part, and each of them is separated. Temperature in part
Thermocouples 8 (a to c) are arranged as sensors . Further, since the head of the bolt 5 is sunk in the counterbore 11 on the front surface of the large diameter portion of the nozzle adapter 3, the heater 7d is brought into close contact with this surface. Therefore, the heater 7a
The barrel 2 is heated, and the heater 7b moves to the nozzle adapter 3
The large diameter part is heated, and the micro heater 12 of the heater 7d is heated.
Heats the small diameter part of the nozzle adapter 3,
Surround the counterbore hole 11 on the front of the large diameter part of 3 with the heater 7d.
Shut off from the air, heater 7d from the head of bolt 5
Heat dissipation is prevented and the heater 7c heats the nozzle 4 and heats it.
The heater 7e heats the tool hook 10 of the nozzle 4. Thermoelectric
The pair 8a detects the resin temperature inside the barrel 2, and the thermocouple 8
b detects the resin temperature inside the nozzle adapter 3 and
The pair 8c detects the resin temperature inside the nozzle 4. Temperature control
The control device 9 includes a barrel portion, a nozzle adapter portion, and a nozzle.
Temperature control of the barrel part independently, barrel 2, nozzle adaptation
The resin temperature inside each part of the nozzle 3 and nozzle 4
It is easy to maintain the proper temperature of the cage, and
Tree inside barrel 2, nozzle adapter 3 and nozzle 4
No "unevenness" in the oil temperature will occur.

FIG. 3 shows a second embodiment, which differs from the first embodiment in the construction of the nozzle 4 and the heater 7d. In this embodiment, the nozzle 4 has a tool-hanging portion 10 having substantially the same diameter as other nozzle portions, and the outer peripheral surface of the nozzle 4 is
And the tool hanging portion 10 is covered with one heater 7c. In this way, by making the diameter of the tool hanging portion 10 of the nozzle 4 the same as that of the other nozzle portions, the heater 7e in the first embodiment can be omitted.

The heaters corresponding to the heater 7d in this embodiment are the heater 7f and the heater 7f.
The heater 7f is attached so as to cover the front surface of the nozzle adapter 3 facing the counterbore 11 of the large diameter portion, and the heater 7g is attached so as to cover the outer peripheral surface of the small diameter portion of the nozzle adapter 3. It In this case as well, the function relating to heating is the same as that of the heater 7d of the first embodiment, but a heater of the same kind as the heater 7a or the heater 7c in the barrel 2 or the nozzle 4 can be used in combination, and the cost is low. Therefore, the heater 7a heats the barrel 2.
Then, the heater 7b heats the large diameter portion of the nozzle adapter 3.
Then, make the counterbore hole 11 on the front of the large diameter part of the nozzle adapter 3
The heater 7f shuts off the surrounding air and the heater 7f
Prevents heat radiation from the head of the bolt 5 and the heater 7g
The small diameter part of the adapter 3 is heated, and the heater 7c is the nozzle.
4 and the tool hook 10 are heated.

FIG. 4 shows a third embodiment, which is a combination of the structures of the first and second embodiments, in which the outer peripheral surface of the nozzle 4 and the tool hooking portion 10 are one heater 7.
It is covered with c and the large diameter part of the nozzle adapter 3 is spotted.
The front surface facing the drilled hole 11 and the outer peripheral surface of the small diameter portion are covered with a heater 7d having a trapezoidal annular cross section. Heater 7d
Is provided with a micro heater 12 facing the periphery of the small diameter portion of the nozzle adapter 3. According to the third embodiment,
First, there is the action effect of improved thermal efficiency since the second heater nozzle portion with operational effects embodiment achieved, the number of heaters is not less dispersed in the nozzle adapter portion.

[0013]

EFFECT OF THE INVENTION In the cylinder assembly of the injection unit
The heater is the outer surface of the barrel and the large nozzle adapter.
Align the outer peripheral surface of the diameter part with the counterbore hole of the large diameter part of the nozzle adapter.
Including the front surface, the outer peripheral surface of the small diameter part and the tool hanging part of the nozzle.
Since the outer peripheral surface is separated and covered, the barrel and nozzle adapter
The nozzle including the large diameter part and the small diameter part of the
Can be heated separately by the nozzle, nozzle adapter
Heat the hole in the front of the large diameter part of the
Since it shuts off, the heat radiation from the bolt head is heated by the heater.
The temperature sensor can prevent the barrel and nozzle
The resin temperature inside the nozzle and the nozzle separately
, Barrel part, nozzle adapter part and nozzle part
Temperature can be controlled independently by a temperature control device.
The temperature control device is barrel, nozzle adapter and nozzle.
Since the resin temperature inside the battery is maintained in an appropriate condition,
Of the resin temperature inside the nozzle, nozzle adapter and nozzle.
The "unevenness" is reduced and the barrel, nozzle adapter and
Since the fluidity of the resin inside the nozzle is improved, a good quality molded product can always be obtained.

[Brief description of the drawings]

FIG. 1 is a front view of a main part (conventional example, partial cross section).

FIG. 2 is a front view of a main part (first embodiment, partial cross section).

FIG. 3 is a front view of a main part (second embodiment, partial cross section).

FIG. 4 is a front view of a main part (third embodiment, partial cross section).

[Explanation of symbols]

1 Cylinder Assembly 2 Barrel 3 Nozzle Adapter 4 Nozzle 5 Bolt 6 Screw 7 Heater 8 Temperature Sensor 9 Temperature Control Device 10 Tool Hook 11 Counterbore 12 Micro Heater

Claims (1)

(57) [Claims] 1. A cylinder assembly in which a nozzle is attached to a tip of a barrel via a nozzle adapter, wherein a head of a bolt for fixing the nozzle adapter to the barrel is formed on a front surface of a large diameter portion of the nozzle adapter. It is submerged in the counterbore, and the outer peripheral surface of the barrel and the large diameter part of the nozzle adapter
Before facing the outer peripheral surface of the nozzle, the counterbore hole of the large diameter part of the nozzle adapter
Surface, the outer peripheral surface of the small diameter portion and the outer peripheral surface including the tool hanging portion of the nozzle so as to cover these surfaces, and the barrel portion ,
Is separated into nozzle adapter portion and the nozzle portion and the heater are mounted respectively, barrels, Nozuruadapu
A cylinder assembly for an injection unit, wherein temperature sensors are mounted on the nozzle and the nozzle, respectively , and are connected to a temperature control device.