JPH0825521A - Formation and apparatus for helix - Google Patents

Abstract

PURPOSE:To enable a helix to be manufactured highly efficiently and accurately through Injection molding without the need of a cutting a flash removing process or the like by attaching shaft pins to the side end mold and shaft securing part of an extruding mold respectively in use; of a molding apparatus, and thereafter forming a helix through molding of a plastic. CONSTITUTION:By separating outside molds 28, 28', a side end mold 12 is isolated from a peripheral surface mold 11 so as to release the tip end of the peripheral surface mold 11, and by operating an actuator 25. an extruding mold 13 is kept in a state where it is pushed into the recession in the peripheral surface mold 11. By keeping this state, a shaft pin 4 is fitted In the shaft securing part of the extruding mold 13 tip end. Next, by operating the actuator 25, the extruding mold 13 Is extracted In order for withdrawing the tip end surface to the side end part 15 position of the peripheral surface mold 11. In addition, a shaft pin 4 is fitted in the shaft securing part of the side end mold 12, and a screw of a retaining mechanism 18 is tightened for fastening the shaft pin 4. Then, the side end mold 12 is joined to the peripheral surface mold 11, and further the outside molds 28, 28' are joined thereto. At this time, the injection passage 22 of the side end mold 12 is connected to the injection passage 29 of the outside mold 28. In this state a plastic is injected for molding a shaft body 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding method and apparatus for manufacturing a spiral member, which is attached to a suction port of a vacuum cleaner and used as a rotary member for rubbing the surface of a carpet or the like, by injection molding.

[0002]

2. Description of the Related Art A rotary member 1 shown in FIG. 1 is attached to a suction port of a vacuum cleaner in order to rub a surface of a carpet or the like and scrape out dust. In this rotary member 1, rubber thin plates 3 and 3 are spirally provided on the surface of a plastic shaft body 2, and metal shaft pins 4 and 4'are attached to both ends. This thin plate 3 is made of a soft plastic material in which grooves 5 and 5 having wide inner parts are spirally formed in a shaft body 2 and the roots of the thin plates 3 and 3 are held in the grooves 5 and 5. Base 6,
It is attached by inserting 6 while spirally deforming it along the groove. Further, a gear 8 is formed at one end of the shaft body 2 via a narrowed neck portion 7.

In the conventional manufacturing method, the shaft body 2 is manufactured by extrusion molding. That is, a long rod having a spiral groove formed continuously is formed continuously, and this is cut into an appropriate length,
Further, drill holes at both ends. The thin plate 3 is attached to the shaft body, and the pin shafts 4 and 4'are press-fitted into the holes to complete the process.

In this manufacturing method, a cutting operation is required, and a deburring operation for removing a burr generated at the cutting portion at the time of cutting is required, which is unsatisfactory in production efficiency. Furthermore, mounting of the shaft pin requires complicated work such as drilling, and the holes are likely to be displaced.
In particular, when the surface shape of the shaft body is a non-circular complex shape, it is difficult to determine the center position, and this positional deviation frequently occurs.

Such an inconvenience can be solved by manufacturing the shaft body by injection molding. However, a shape in which a groove having a wide inner part extending in a spiral shape cannot be formed even if a split mold is used.

[0006]

Therefore, the present invention makes it possible to manufacture a spiral body such as the above-mentioned shaft body by injection molding, omitting the conventional work such as cutting and deburring, and The purpose is to enable efficient and highly accurate manufacturing.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides a peripheral surface type forming a peripheral surface of a spiral body and a portion near the peripheral surface of one end surface, and a peripheral surface die which can be joined to and separated from the peripheral surface die. The side end die that forms the other side end face portion, the shaft attachment part that is provided in the center of the inner surface of this side end die, and the shaft pin is attached before the plastic injection, and the round rod shape that goes in and out of the peripheral surface die. It becomes possible, and when it is pulled out, the tip end surface forms the central portion of the one side end surface of the spiral body, and the extrusion die which can be pushed in and extruded while rotating the formed spiral body, and this extrusion die A shaft mounting part, which is provided at the center of the inner surface and is equipped with a shaft pin before plastic injection, and a rear end of the extrusion die are rotatably connected to each other, and the extrusion die is freely rotated and pushed into and out of the peripheral die. Forming device of spiral body consisting of ejecting actuator Used, the shaft mounting portion of the side edge type, and extrusion die, fitted with a shaft pin, respectively, is a method of molding a spiral body and forming a spiral body by injecting plastic later.

Further, the present invention is an apparatus used in the above method, that is, a peripheral surface type forming a peripheral surface of the spiral body and a portion near the peripheral surface of one side end surface, and the peripheral surface type can be joined and separated. , A side end mold that forms the other side end surface portion of the spiral body, a shaft mounting portion that is provided at the center of the inner surface of this side end mold, and a shaft pin is mounted before plastic injection, and is a round bar shape,
Extrusion that can be inserted into and removed from the peripheral surface mold, and when withdrawn, the front end surface forms the central part of the one side end surface of the spiral body and is pushed in and can be extruded while rotating the formed spiral body. The mold and the center of the inner surface of this extrusion mold,
It consists of a shaft mounting part to which a shaft pin is mounted before plastic injection, and an actuator which is rotatably coupled to the rear end of the extrusion die and pushes it into and out of the peripheral die while freely rotating the extrusion die. It includes a spiral forming device.

Further, in the present invention, in the above device, the shaft mounting portion has a holding mechanism for holding a shaft pin such as a screw or a magnet, and the side end die has another die portion for forming a gear or the like. The peripheral surface type and the side end type include those which are fitted and held in an outer mold which can be divided.

[0010]

EXAMPLES Hereinafter, examples illustrating the present invention will be specifically described.

The molding apparatus 10 is for manufacturing a spiral body, specifically, the shaft body 2. This device 10
It is roughly composed of a peripheral surface mold 11, a side end mold 12, and an extrusion mold 13.

The inner surface of the peripheral surface mold 11 comprises a peripheral surface portion 14 and side end portions 15. The peripheral surface portion 14 forms a peripheral surface of a spiral body, and a ridge 1 for forming a groove on the surface thereof.
Have six. The side end portion 15 forms a portion near the peripheral surface of one side end of the peripheral surface portion 14, and the inner peripheral end thereof has a circular shape. The outer shape of the peripheral surface mold 11 is a cylindrical shape.

The side end mold 12 can be joined to and separated from the side end 15 of the peripheral surface mold 11 and forms a side end of a spiral body when joined. At the center of the inner surface of the side end mold 12, a shaft mounting portion 1 to which a shaft pin 4 is mounted before plastic injection is performed.
7 are provided. The shaft mounting portion 17 is formed of a hole, and a holding mechanism 18 formed of a screw is provided on the side surface of the shaft mounting portion 17. By screwing the screw, the shaft pin can be pressed and held.

Further, the side end die 12 has a separate die portion 19 for forming the neck portion 7 and the gear 8. This separate mold part 19 is provided with a gear mold 20 in the back and a neck mold 21 at the mouth end, and the neck mold 21 is a split mold, and in the drawing, it can be separated in the front-back direction of the drawing. . The side end mold 12 is provided with an injection path 22 that opens to the end of the gear mold 20.

The extrusion die 13 is in the shape of a round bar, is fitted in the side end portion 15 of the peripheral surface die, and can be put in and out of the peripheral surface die 11. When the extrusion die 13 is extracted from the peripheral surface die 11, the tip end surface 23 thereof forms the side end surface of the spiral body together with the side end portion 15. At the center of the inner surface of the extrusion die 13,
A shaft mount 24 is provided to which the shaft pin 4'is mounted before the plastic injection. The shaft mounting portion 24 is formed of a hole and holds the shaft pin 4'by frictional force.

A hydraulic actuator 25 (only the tip is shown) is rotatably connected to the rear end of the extrusion die 13. That is, the thrust bearing 26 is attached to the rear end of the extrusion die 13, the tip of the actuator 25 is in contact with the thrust bearing 26, and the periphery of the thrust bearing 26 is covered with a case 27 so that the two are inseparably connected. Therefore, when the tip of the actuator 25 moves forward, the extrusion die 13 is pushed through the bearing 26, the extrusion die 13 advances in a freely rotatable state, and conversely, when the tip of the actuator 25 retracts, the extrusion die 13 moves. It is pulled through the case 27.

The peripheral surface mold 11 and the side end mold 12 are fitted and held in outer molds 28, 28 'which can be divided. That is, the peripheral surface mold 11 is fixed to the outer mold 28 and the side end mold 12 is fixed.
After being joined to the peripheral surface mold 11, the other outer mold 28 '
When joined to 8, the peripheral surface mold 11 and the side end mold 12 are entirely covered with the outer molds 28 and 28 '. An injection path 29 connected to the injection path 22 is formed in the outer mold 28.

Since the molding apparatus 10 has the above-mentioned structure, it is used by the molding method as follows.

First, the outer molds 28 and 28 'are separated, the side end mold 12 is separated from the peripheral surface mold 11, the tip of the peripheral surface mold 11 is opened, and the actuator 25 is operated to rotate the extrusion mold 13 around. It is in a state of being pushed all the way into the surface mold 11. In this state, the shaft pin 4'is fitted into the shaft mounting portion 24 at the tip of the extrusion die 13. Next, the actuator 25 is operated to pull out the extrusion die 13 (see FIG. 3), and the tip end surface 23 is moved to the peripheral surface die 1.
1 to the side end 15 position. Further, the shaft pin 4 is fitted into the shaft mounting portion 17 of the side end mold 12, and the screw of the holding mechanism 18 is tightened to fix the shaft pin 4.

Next, the side end mold 12 is joined to the peripheral surface mold 11,
Further, the outer molds 28 and 28 'are joined. At this time, the injection path 22 of the side mold 12 is connected to the injection path 29 of the outer mold 28.
In this state, plastic is injected, and thereby the shaft body 2 is molded (see FIG. 4).

Next, the outer molds 28, 28 'are separated, the screws of the holding portion 18 are loosened, the neck mold 21 of the separate mold portion 19 is opened, and the side end mold 12 is separated from the peripheral surface mold 11. Further, the actuator 25 is operated to move the extrusion die 13 to the peripheral end die 1.
Push in 1. As a result, the extrusion die 13 is attached to the shaft body 2.
While rotating along the peripheral surface portion 14 of the peripheral surface mold 11,
Push out (see FIG. 5). At this time, the extrusion die 13
Since it rotates together with the shaft body 2, it can be extruded smoothly.

In the above example, the shaft mounting portion is provided with a holding mechanism using a screw, but a holding mechanism having another structure such as a magnet may be used. Since this holding mechanism is intended to prevent the shaft pin from coming off or being displaced during the injection of plastic, it is usually required to provide it only on the shaft mounting portion near the injection path as in the above example. Further, the holding mechanism can be omitted by appropriately setting the position of the injection path.

Further, in the above example, the gear and the neck are formed by the separate mold portion. However, when forming the spiral body without them, the separate mold portion can be omitted. In addition, the mold part of the above example has a neck mold made of a split mold in order to form the neck part. However, various structures may be used according to the shape formed by the mold part. It goes without saying that you can do it.

In the above example, the peripheral surface type and the side end type are
Although the structure is such that the structure is fitted and held in the outer mold which can be divided, it goes without saying that a structure without the outer mold is also possible.

Although the above example describes the case where the shaft body is formed, it goes without saying that products having other shapes can be manufactured in the same manner as long as they are spiral bodies.

[0026]

According to the molding method and apparatus of the present invention, as described above, the product is extruded by the extrusion die while being rotated, so that the spiral body can be produced by injection molding. . Therefore, the work of cutting and deburring as in the case of using the conventional extrusion molding is unnecessary, and the production efficiency can be improved. Further, since the shaft pin is mounted at the same time as the formation of the spiral body, the conventional work of mounting the shaft pin is unnecessary, and the position thereof is accurate.

Further, in the molding method of the present invention, since the shaft pins are separate ones at both ends of the spiral body, when the shaft pins are attached to the side end mold and the extrusion mold, when the plastic is injected, the plastic The shaft pin does not bend due to flow resistance, and the mounting position and angle are extremely accurate.

Further, when the peripheral surface type and the side edge mold are fitted and held in the dividable outer mold like the above-mentioned apparatus, the peripheral surface type and the side edge mold are small. , Low cost. In addition, it is possible to easily realize a configuration in which a large number of peripheral surface molds are provided in parallel, whereby a large number of products can be molded at once.

[Brief description of drawings]

FIG. 1 is a perspective view showing a rotary member of a suction port of a vacuum cleaner, to which a spiral body molded according to the present invention is applied.

FIG. 2 is a side sectional view of one embodiment of the present invention.

FIG. 3 is an explanatory side cross-sectional view showing a molding process according to the same example, showing a state where a shaft pin is attached.

FIG. 4 is an explanatory side cross-sectional view showing a molding process according to the same example, showing a case of plastic injection.

FIG. 5 is an explanatory cross-sectional side view showing a molding process according to the same example, showing a product being taken out.

[Explanation of symbols]

1 ... Rotating member, 2 ... Shaft, 5 ... Groove, 4, 4 '... Shaft pin,
7 ... Neck part, 8 ... Gear, 10 ... Spiral body forming device, 11
... peripheral surface type, 12 ... side end type, 13 ... extrusion type, 14 ... peripheral surface part, 15 ... side end part, 16 ... ridge, 17 ... shaft mounting part, 1
8 ... Holding mechanism, 19 ... Separate mold part, 20 ... Gear mold, 21 ...
Mold for neck, 23 ... Tip surface, 24 ... Shaft mounting portion, 25 ... Actuator, 26 ... Bearing, 27 ... Case, 2
8, 28 '... External type.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B29L 31:08

Claims (5)

[Claims] 1. A peripheral surface die that forms a peripheral surface of the spiral body and a portion of one end surface near the peripheral surface and a peripheral surface die that can be joined to and separated from the peripheral surface die to form another side end surface portion of the spiral body. Side end mold, a shaft mounting part provided at the center of the inner surface of this side end mold, and a shaft pin to which a shaft pin is mounted before plastic injection, and a round bar shape,
Extrusion that can be inserted into and removed from the peripheral surface mold, and when withdrawn, the front end surface forms the central part of the one side end surface of the spiral body and is pushed in and can be extruded while rotating the formed spiral body. The mold and the center of the inner surface of this extrusion mold,
It consists of a shaft mounting part to which a shaft pin is mounted before plastic injection, and an actuator which is rotatably coupled to the rear end of the extrusion die and pushes it into and out of the peripheral die while freely rotating the extrusion die. Forming a spiral body characterized by forming a spiral body by attaching shaft pins to the side end-type and extrusion-type shaft attachment portions, respectively, and then injecting plastic using a spiral-shaped forming device. Method. 2. A peripheral surface die that forms a peripheral surface of the spiral body and a portion near the peripheral surface of one end surface, and a peripheral surface die that can be joined to and separated from this peripheral surface mold to form the other side end surface portion of the spiral body. Side end mold, a shaft mounting part provided at the center of the inner surface of this side end mold, and a shaft pin to which a shaft pin is mounted before plastic injection, and a round bar shape,
Extrusion that can be inserted into and removed from the peripheral surface mold, and when withdrawn, the front end surface forms the central part of the one side end surface of the spiral body and is pushed in and can be extruded while rotating the formed spiral body. The mold and the center of the inner surface of this extrusion mold,
It consists of a shaft mounting part to which a shaft pin is mounted before plastic injection, and an actuator which is rotatably coupled to the rear end of the extrusion die and pushes it into and out of the peripheral die while freely rotating the extrusion die. Spiral molding device. 3. The apparatus for forming a spiral body according to claim 2, wherein the shaft mounting portion has a holding mechanism that holds a shaft pin such as a screw or a magnet. 4. The apparatus for forming a spiral body according to claim 2, wherein the side end die has another die portion forming a gear or the like. 5. The apparatus for forming a spiral body according to claim 2, 3 or 4, wherein the peripheral surface mold and the side end mold are fitted and held in an outer mold which is separable.