JPH0242430Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a cylindrical plastic injection molding apparatus having an opening on the side.

BACKGROUND TECHNOLOGY Conventionally, a cylindrical injection molding apparatus has a mold frame provided around a central axis via an injection space, and molds are ejected from well-balanced injection ports arranged at an angle of, for example, 120 degrees around the central axis. It was molded by injecting plastic into the frame.

Problems to be Solved by the Invention In the prior art, the injection ports are arranged so that the injection force is evenly applied to the central axis, so there is no problem in molding a normal cylinder. When trying to mold a certain cylindrical body, the injection force applied to the opening becomes weaker, causing an imbalance in the force applied to the central axis, causing the cylinder to bend in the direction of the opening, making it impossible to mold a cylindrical body of uniform thickness. .

Means for Solving the Problems Therefore, the present invention provides an opening support that abuts the central axis opposite to the side opening of the cylinder, and also provides the mold that is located on the opposite side of the opening support. By providing an injection port in the frame, the central axis is pressed against the opening support during injection molding to stabilize it, thereby providing an apparatus that can easily and accurately injection mold a side opening cylinder.

Function The device of the present invention is provided with an opening support that abuts the central axis opposite to the side opening of the cylindrical body, and an injection port is provided in the formwork located on the opposite side of the opening support. This provides an acting force that presses the central axis in the direction of the opening during plastic injection, and this acting force is received by the opening support to stabilize the central axis without deviation, making it easy to open the cylinder with side openings. Moreover, it can be precisely injection molded.

Example The example of FIG. 1 and FIG.
As shown in the figure, the present invention relates to an apparatus for forming a cylinder 1 having a plurality of openings 2 separated by ribs 3 on the side thereof. The cylindrical body 1 is used as a cartridge-type toner powder container attached to a developing device for electrophotography, and one end is closed with an integral closing wall 4 having a mounting piece 5. The other end is a hollow part 7 to which a cap 6 can be attached after molding.
The opening 2 is covered with a peelable sealing member, and is configured to be peeled off after being attached to the device, and the toner powder inside is discharged.

In Figures 1 and 2, 10 is the central axis;
The surrounding area is passed through the injection space of the cylindrical body 1 into the formwork 1.
1 and 12 are divisibly covered. The formwork 12 covers the rib 3 portion of the cylindrical body 1, but the portion facing the opening 2 is open, and an opening support 13 is placed in the opening portion.
is occupying the position. The tip of the open support 13 is in contact with the surface of the central shaft 10, while the rear end is supported by a strong support 14. An injection port 15 is provided in the formwork 11 on the opposite side of the opening support 13. The position of the injection port 15 is clearly shown in FIG.

In the embodiment having the above configuration, the injection port 1
When plastic is injected from 5, a large amount of plastic is injected toward the opposite side of the opening 2 of the cylindrical body 1, and the central axis 10 is subjected to a pressing force in the direction of the opening 2, but the opening support 13 The two parts strongly support and oppose the central shaft 10, and the central shaft 10
is stabilized at a predetermined position within the molds 11 and 12, the plastic is evenly distributed within the injection space of the molds 11 and 12, and the side opening cylinder is molded without undergoing any deformation. Become.

Effects As described above, according to the injection molding apparatus for a side-opening cylindrical body according to the present invention, an opening support body that faces the side opening portion of the cylindrical body and abuts on the central axis is provided, and the opening support By arranging an injection port in the mold on the opposite side of the body, a force is applied to press the center axis in the opening direction when plastic is injected, and this force is received by the opening support and the center This has the effect of stabilizing the shaft without causing deviation, and making it possible to easily and accurately injection mold the side-opening cylindrical body.

[Brief explanation of the drawing]

Fig. 1 is a schematic front longitudinal cross-sectional view of an embodiment of the device of the present invention, showing the main parts longitudinally, Fig. 2 is a schematic cross-sectional view taken along the - line, and Fig. 3 is a schematic cross-sectional view of the molded product. FIG. 4 is a perspective view showing an example, and FIG. 4 is a longitudinal sectional view of the molded product. DESCRIPTION OF SYMBOLS 1... Cylindrical body, 2... Side opening, 10... Central shaft, 11, 12... Formwork, 13... Opening support body.

Claims (1)

[Scope of utility model registration request] a central axis, a mold forming an injection space leaving a side opening of the cylinder to be molded around the central axis, and an opening that abuts the central axis opposite to the side opening of the cylinder. An injection molding apparatus for a side-open cylinder body, comprising a support body and an injection port provided in the mold frame and located on the opposite side of the open support body about the central axis.