JPH0798354B2 - Distributor head - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention consists of a thermoplastic material which, in the region of the supply channel for the thermoplastic material, has an annular groove arranged in the radial plane which is associated with the upper part of the dispensing head. It relates to a distributor head with a conical outer wall for producing hose sections for blow-molded articles.

[0002]

2. Description of the Prior Art When producing hose sections as preforms for producing blow-molded articles of thermoplastic material, it is difficult to ensure a uniform distribution of the incoming material in the distributor head. . In a known configuration, it is proposed to configure the distributor head, or here the blowhead, to produce a uniform length of flow distance distributed over the peripheral surface for the flowing material (German Patent No. 1). 3225371).

However, all previously proposed configurations for distributor heads have a weakening point in the hose region which occurs here in the confluence region of both material streams distributed in the annular groove. Manufactured from hose segment,
The problem of negatively affecting the strength of products such as bellows covering the hinge joints cannot be solved.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a distributor head for producing a hose section as a preform for the further production of blow-molded articles of thermoplastic material, on both sides of an annular groove. It is designed to eliminate the formation of weakened points in the confluence region of the two confluent material streams.

[0005]

The measures taken according to the invention for solving the abovementioned problems are based on the conical outer wall of the distributor head on the side facing away from the supply passage, starting from an annular groove, A second groove is provided axially toward the tapered side of the dispenser head, spaced apart from the lower end of the dispenser head and spaced apart in the form of a tapered wedge, further comprising an annulus. A deflection guide is provided for guiding the material flowing into the connection region between the annular groove and the second groove from both sides of the groove into the second groove so as to prevent a dead water region. .

[0006] The advantage of the distributor head according to the invention is that the material flows axially towards the lower end of the distributor head, on the side of the annular groove opposite the feed passage, where the material streams on both sides meet. A second groove is provided to soften the flow, so that a substantially uniform pressure ratio is ensured in the deflection gap over the entire circumference. As it flows through the second groove, a tight confluence of both partial streams takes place. This ensures that the so-called weakenings inside the hose section are reliably excluded.

According to an advantageous configuration of the invention, the annular groove is
In the connection region to the second groove, there is a protrusion that is formed in a wedge shape toward the second groove, and two connection passages that are respectively arranged in the flow direction of the annular groove are formed. .
This softens the deflection of both merging material streams in the connection region, since the deflection takes place with a relatively large radius.

In a further advantageous embodiment of the invention, the axis of the second groove is oriented parallel to the longitudinal axis of the distributor head. This makes use of a simple manufacturing method for manufacturing the second groove.

In a further advantageous refinement of the invention, the axis of the second groove forms an angle with the axis of the distributor head which opens up to the tapered end of the distributor head, up to 5 °. ing. With such an arrangement, the pressure of the flowing material is varied to a sufficient extent in the connection area, which is offset by 180 ° with respect to the supply passage.

According to a further advantageous characteristic of the invention, an annular groove is provided between the receiving bush for holding the distributor head and the conical outer wall of the distributor head, the tapered end of the distributor head. An annular gap is provided up to the turning edge provided at. Such a gap is necessary in order to cause the flow over the entire circumference of the dispensing head to the turning edge.

In another configuration of the invention, the turning edge is formed by a continuous curve. With this, almost 1
A satisfactory material flow in the turning region over 80 ° is softened.

[0012]

The present invention will be described below in detail with reference to the embodiments shown in the drawings. The distributor head 1 shown in FIG. 1 has a conical shaped outer wall 3 with a tubular groove 2 at the large diameter end of the outer wall. The distributor head 1 has a through hole 14 inside. Indexing notch 6 for aligning and assembling distributor head 1
Is provided which, in combination with the pin, indexing pin 15, ensures the correct positioning of the distributor head 1 on the machine (not shown) used.

FIG. 2 shows a second groove 5 of the distributor head 1 having the configuration of a wedge-shaped projection 7 and a connecting passage 12.
The top view in the range of is shown. The installation shown in FIG. 3 for the distributor head 1 shows a supply channel 11 from which the thermoplastic material to be injection-molded is introduced into the tubular channel 2. The thermoplastic material is circumferentially distributed on both sides in the tubular groove 2 and merges again in the joint region on the side opposite to the supply channel 11 into one co-current flow, which is then vertically injection-molded. It is deflected approximately in the axial direction of the head.

Between the receiving bush 13 and the conical outer wall 3 of the distributor head 1 there is also formed a conical annular gap 8 in which the thermoplastic material is below the distributor head 1. It flows to the end. In the confluence region of both material flows on the side opposite to the supply passage 11, the second groove 5
It is provided that the groove deflects both merged material flows in a substantially axial direction and that a substantially constant pressure ratio is distributed in the deflection gap 9 over the circumferential surface. .

Inside the distributor head is a piston 16, which is moved downwards by the material to be fed. To manufacture hoses,
The piston is hydraulically guided back to its predetermined starting position and presses the injection-molded material through the corresponding nozzle. After the material has been diverted into the diverting gap 9, it is lifted up against the general direction of material flow.

[0016]

As described above, according to the present invention, the conical outer wall is provided on the side of the distributor head opposite to the supply passage.
Starting from the annular groove, there is provided a second groove tapered axially towards the tapered side of the distributor head, spaced apart from the lower end of the distributor head and tapered in a wedge shape. From both sides of the annular groove and the second
For the further production of blow-molded articles of thermoplastic material by providing a deflection guide for guiding the material flowing into the connection area with the groove into the second groove so that dead water areas do not occur. It is possible to provide a distributor head for the production of hose sections as molded parts.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a distributor head.

FIG. 2 is a plan view showing a transition region from an annular groove to a second groove.

FIG. 3 is a cross-sectional view of the dispenser head in the assembled state.

[Explanation of symbols]

 1 Distributor head 2 Annular groove 3 Conical outer wall 4 Deflection edge 5 Second groove 6 Indexing notch 7 Wedge-shaped protrusion 8 Annular gap 9 Deflection gap 10 Hose outlet 11 Supply passage 12 Connection passage 13 Receiving bush 14 Inside through hole 15 Indexing pin 16 Piston

Claims (6)

[Claims] 1. A blow molded article of thermoplastic material having an annular groove arranged in a radial plane assigned to the upper part of the dispensing head in the region of the supply channel for the thermoplastic material. In a distributor head with a conical outer wall for producing a hose section, an annular groove (2) is provided in the conical outer wall (3) on the side of the distributor head (1) opposite the feed passage (11). ) Starting axially towards the tapered side of the distributor head (1) and spaced apart from the lower end of the distributor head (1) by a tapered wedge-shaped configuration. Two grooves (5) are provided, and the material that flows into the connection region between the annular groove (2) and the second groove (5) from both sides of the annular groove (2) is treated with dead water. A deflection guide is provided which guides into the second groove (2) so that no area is created. Distributor head characterized by. 2. The annular groove (2) has, in the region of connection to the second groove (5), a projection (7) which is wedge-shaped towards the second groove (5), Distributor head according to claim 1, characterized in that it further comprises two connecting passages (12) arranged respectively in the direction of flow of the annular groove (2). 3. Distributor head according to claim 1 or 2, characterized in that the axis of the second groove (5) is oriented parallel to the longitudinal axis of the distributor head (1). 4. The axis of the second groove (5) forms an angle with the axis of the distributor head (1) of up to 5 ° which opens towards the tapered end of the distributor head. Distributor head according to claim 1 or 2, characterized in that 5. From the annular groove between the receiving bush (13) holding the dispenser head (1) and the conical outer wall of the dispenser head (1), the tapered end of the dispenser head. Distributor head according to any one of claims 1 to 3, characterized in that an annular gap (8) is provided up to the turning edge (4) provided in the. 6. Distributor head according to any one of claims 1 to 5, characterized in that the turning edge (4) is formed by a continuous curve.