JP2003039513A - Screw cylinder of injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the transfer of heat by reducing the contact area with a flange from a cylinder to reduce the temperature rise of a material charging port by forming a flange groove to the flange and forming a spline-shaped groove to the cylinder while forming a cylinder groove to the cylinder. SOLUTION: In the screw cylinder of the injection molding machine, the contact area (heat transfer area) between the cylinder (1) and the flange (6) is reduced by either one of the flange grooves (10A-10C) formed to the flange (6), the spline-shaped groove (50) formed to the cylinder (1) and the cylinder grooves (30A-30C) formed to the cylinder (1) and the transfer of heat to the flange (6) is reduced to prevent the melting and adhesion of the resin material of the material charging port (5).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw cylinder of an injection molding machine, and more particularly, to reducing the contact area between the outer peripheral surface of the cylinder and the inner peripheral surface of the flange to reduce the heat transfer area, thereby introducing the material for the flange. The present invention relates to a new improvement for preventing the temperature rise of the mouth portion and facilitating the temperature control of the material feeding port portion and the temperature control of the cylinder by the cooling water passed through the cooling water hole of the flange.

[0002]

2. Description of the Related Art As a screw cylinder of an injection molding machine of this type which has been conventionally used, the structure shown in FIG. 4 is generally adopted. In FIG. 4, reference numeral 1 denotes a cylinder having a cylindrical shape as a whole and having a through hole 1a in which a screw 2 is provided. The outer peripheral surface 1A of the cylinder 1 has a plurality of heater portions 3a, 3b. A heater 4 composed of 3c is attached. A flange 6 having a material feeding port 5 is firmly fixed to a rear portion 1b of the outer peripheral surface 1A of the cylinder 1 via a shrinkage fitting portion 7. The material feeding port 5 communicates with the through hole 1a. is doing. A cooling water hole 8 as a well-known cooling jacket is formed around the material inlet 5 of the flange 6 along the outer circumference of the cylinder 1, and the screw 2 is rotated by a driving device (not shown). It is configured to be driven.

Next, the operation will be described. First, the resin material charged and supplied from the material charging port 5 of the flange 6 is
It is sent to the tip side by the rotation of the screw 2 in the cylinder 1, at which time the cylinder 1 is heated by the heater 4,
The resin material is melted from the pellet form by the heat and the shear heat insulation due to the rotation of the screw 2, and is transferred to the tip side.

[0004]

Since the screw cylinder of the conventional injection molding machine is configured as described above,
The following issues existed. That is, the resin material supplied from the material input port is heated by the cylinder heated by the heater, but it is necessary to prevent the resin material in the material input port portion from being melted and fixed by the heat transmitted from the cylinder. Therefore, it is necessary to prevent the temperature of the material input port from rising. for that reason,
Water or hot water is passed through a hole for cooling water provided around the material inlet of the flange to adjust the temperature. On the other hand, the heat from the heater portion in the position immediately adjacent to the flange heats the cylinder and also directly raises the temperature of the flange through the cylinder, and is not effectively used for heating the cylinder. It is extremely difficult to control these two contradictory temperature controls at the same time, because it is necessary to cool the cylinder temperature rise due to the heat from the heater part and the material input port part of the flange. It was the biggest neck.

The present invention has been made in order to solve the above problems, and in particular, the contact area between the outer peripheral surface of the cylinder and the inner peripheral surface of the flange is reduced to reduce the heat transfer area. In order to prevent the temperature rise of the material input port part of, and to easily achieve the temperature control of the material input port part by the cooling water passing through the cooling water hole of the flange and the cylinder temperature control by the heater without affecting each other. An object of the present invention is to provide a screw cylinder of the injection molding machine.

[0006]

A screw cylinder of an injection molding machine according to the present invention includes a cylinder having a heater formed of a plurality of heaters on an outer peripheral surface thereof, and a screw provided in a through bore of the cylinder. In a screw cylinder of an injection molding machine, which is fixed to a rear portion of the cylinder and has a flange having a material inlet and a cooling water hole, a flange formed on an inner peripheral surface of the flange and not in contact with an outer peripheral surface of the cylinder. A cylinder having a groove in which the contact area where the inner peripheral surface and the outer peripheral surface directly contact each other is reduced only by the flange groove portion, and a cylinder having a heater composed of a plurality of heater portions on the outer peripheral surface; A screw of an injection molding machine including a screw provided in a through-hole of a cylinder and a flange fixed to a rear portion of the cylinder and having a material inlet and a cooling water hole. In Ryu cylinder, wherein it is the rear part of the outer circumferential surface of the cylinder flange is provided a structure groove of the spline shape along the axial direction is formed, also, the groove of the flange grooves or splines shape,
A cylinder having a heater composed of a plurality of heaters on the outer peripheral surface, which is configured to communicate with the outside air by an outside air communication hole formed in the flange and communicating with the outside air,
In a screw cylinder of an injection molding machine, which comprises a screw provided in a through hole of the cylinder and a flange fixed to a rear portion of the cylinder and having a material inlet and a cooling water hole, The cylinder groove is formed in the rear portion of the outer peripheral surface on which the flange is provided, and the heat insulating material is provided in the cylinder groove.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a screw cylinder of an injection molding machine according to the present invention will be described below with reference to the drawings. It should be noted that the same or equivalent parts as those of the conventional example are designated by the same reference numerals for description. In FIG. 1, reference numeral 1 is a cylinder having a cylindrical shape as a whole and having a through hole 1a in which a screw 2 is provided.
A heater 4 including a plurality of heater portions 3a, 3b, 3c is mounted on the outer peripheral surface 1A of the.

A flange 6 having a material feeding port 5 is firmly fixed to the rear portion 1b of the outer peripheral surface 1A of the cylinder 1 through a shrinkage fitting portion 7. The material feeding port 5 is the through hole 1a. It communicates with the inside. A cooling water hole 8 as a well-known cooling jacket is formed around the material inlet 5 of the flange 6 along the outer circumference of the cylinder 1, and the screw 2 is rotated by a driving device (not shown). It is configured to be driven.

The inner peripheral surface 6A of the flange 6 is provided with flange grooves 10A, 10B and 10C which are formed so as not to be in contact with the outer peripheral surface 1A of the cylinder 1. Each of these flange grooves is provided. Direct contact between the inner peripheral surface 6A of the flange 6 and the outer peripheral surface 1A of the cylinder 1 by 10A, 10B, and 10C is at the insertion portion 11A, the central portion 11B, and the rear end portion 11C at three locations. Then, the contact area, that is, the heat transfer area from the cylinder 1 to the flange 6 becomes about 1/3, and the heat transfer state is greatly reduced.

At both ends of the flange 6, an outside air communication hole 20 is formed along the radial direction of the cylinder 1, and the outside air communication hole 20 is formed in the flange groove 10A.
By communicating with the outside air, heat in the space inside the flange grooves 10A to 10C is radiated to the outside by convection with the outside air, and the temperature rise of the flange 1 is prevented.

Next, the operation will be described. First, the resin material charged and supplied from the material charging port 5 of the flange 6 is
It is sent to the tip side by the rotation of the screw 2 in the cylinder 1, at which time the cylinder 1 is heated by the heater 4,
The resin material is melted from pellets or the like by the heat and the shear heat insulation due to the rotation of the screw 2, and is transferred to the tip side. In the above case, since the contact area between the inner peripheral surface 6A of the flange 6 and the outer peripheral surface 1A of the cylinder 1 is significantly reduced as compared with the conventional case, heat transfer to the flange 6 is small and therefore the heater 4
Even if the temperature of the cylinder 1 is controlled to the required temperature by the control, the effect of the temperature rise on the cooling water circulating in the cooling water hole 8 is little, and the temperature of the material inlet 5 is controlled to be sufficiently low. Therefore, it is possible to overcome all the above-mentioned problems in the related art.

In the case of another embodiment shown in FIG. 2, the inner peripheral surface 6A of the flange 6 is not subjected to any processing and only the outside air communication hole 20 is formed, and the rear portion of the outer peripheral surface 1A of the cylinder 1 is formed. A spline-shaped groove 50 formed in the axial direction is provided only in 1b, and the spline-shaped groove 5 and the outside air communication hole 20 are communicated with each other to form the spline-shaped groove 5
The heat in the void of 0 is released to the outside through the outside air communication hole 20 to prevent heat transfer to the flange 6. The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof is omitted.

In the case of another embodiment shown in FIG. 3, the inner peripheral surface 6A of the flange 6 is in the same state as the conventional one in which no processing is performed, and the flange 6 of the outer peripheral surface 1A of the cylinder 1 is processed.
Is attached to the rear portion 1b where the cylinder groove 30A,
30B, 30C are formed, and each cylinder groove 30A, 30
A heat insulating material 40 is provided in B and 30C. Therefore, the outer peripheral surface 1A of the cylinder 1 and the inner peripheral surface 6A of the flange 6 are
The contact area between them is the same as that in the case of FIG. 1, and the contact area is reduced, and the same effect as that of FIG. 1 described above can be obtained. Further, heat transfer can be prevented by the air layer. The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

[0014]

Since the screw cylinder of the injection molding machine according to the present invention is constructed as described above, the following effects can be obtained. That is, the heat transfer area from the cylinder to the flange is increased by any of the flange groove formed on the inner peripheral surface of the flange, the cylinder groove formed on the outer peripheral surface of the cylinder, and the spline-shaped groove formed on the outer peripheral surface of the cylinder. By lowering the temperature of the material inlet using the cooling water hole provided in the flange, the heating of the cylinder itself by the heater can be performed sufficiently and efficiently. It is possible to simply and reliably perform temperature control of mutually opposing characteristics such as sufficient heating and suppression of necessary temperature rise to the material injection port, and it is possible to greatly improve the efficiency of injection molding.

[Brief description of drawings]

FIG. 1 is a sectional view showing a screw cylinder of an injection molding machine according to the present invention.

FIG. 2 is a cross-sectional view of an essential part showing another embodiment of FIG.

FIG. 3 is a cross-sectional view of a main part showing another embodiment of FIG.

FIG. 4 is a sectional view showing a screw cylinder of a conventional injection molding machine.

[Explanation of symbols]

1 cylinder 1A outer peripheral surface 1a Through hole 1b rear 2 screws 3a-3c heater part 4 heater 5 Material input port 6 flange 6A inner peripheral surface 7 Shrinkage part 8 Cooling water hole 10A-10C Flange groove 20 Outside air communication hole 30A-30C Cylinder groove 40 insulation 50 spline shaped groove

Claims (4)

[Claims] 1. A plurality of heater parts (3a-3c) on the outer peripheral surface (1A).
(1) having a heater (4) consisting of, a screw (2) provided in the through hole (1a) of the cylinder (1), and fixed to the rear part (1b) of the cylinder (1). In a screw cylinder of an injection molding machine consisting of a flange (6) having a material inlet (5) and a cooling water hole (8), the cylinder (6A) formed on the inner peripheral surface (6A) of the flange (6) The outer peripheral surface (1A) of 1) has a flange groove (10A to 10C) that is not in contact with the inner peripheral surface (6A).
And the outer peripheral surface (1A) directly contact the flange groove
A screw cylinder for an injection molding machine, which is characterized in that it has a reduced number of parts (10A to 10C). 2. A plurality of heater parts (3a-3c) on the outer peripheral surface (1A).
(1) having a heater (4) consisting of, a screw (2) provided in the through hole (1a) of the cylinder (1), and fixed to the rear part (1b) of the cylinder (1). In a screw cylinder of an injection molding machine consisting of a material charging port (5) and a flange (6) having a cooling water hole (8), an outer peripheral surface of the cylinder (1) provided with the flange (6) ( A screw cylinder of an injection molding machine, wherein a spline-shaped groove (50) is formed in the rear portion (1b) of (1A) along the axial direction. 3. The flange groove (10A to 10C) or the spline-shaped groove (50) communicates with the outside air through an outside air communication hole (20) formed in the flange (6) and communicating with the outside air. The screw cylinder of the injection molding machine according to claim 1 or 2. 4. A plurality of heater parts (3a-3c) on the outer peripheral surface (1A).
(1) having a heater (4) consisting of, a screw (2) provided in the through hole (1a) of the cylinder (1), and fixed to the rear part (1b) of the cylinder (1). In a screw cylinder of an injection molding machine consisting of a flange (6) having a material inlet (5) and a cooling water hole (8), the flange (6) of the outer peripheral surface (1A) of the cylinder (1) is It has a cylinder groove (30A ~ 30C) formed in the rear portion (1b) of the outer peripheral surface (1A) provided, the heat insulating material (40) is provided in the cylinder groove (30A ~ 30C). The screw cylinder of the characteristic injection molding machine.