Extrusion blowing structure

Abstract

The utility model relates to a die structure, in particular to an extrusion blowing structure which comprises a blowing rod, the blowing rod comprises a cutting ring, a blowing needle, a blowing needle and a blowing needle head, one end of the blowing needle is connected with the cutting ring, the other end of the blowing needle is connected with the blowing needle head, and at least one blowing hole is formed in the side wall of the blowing needle head; the blowing needle head is connected with the blowing needle, at least one blowing hole is formed in the side wall of the blowing needle head, blow molding is carried out through the blowing hole, and due to the fact that gas is blown out from the side wall of the blowing needle head instead of the bottom of the blowing needle, the situation that materials are accumulated on necks of small-caliber products with square shoulders can be avoided.

Description

Technical Field

[0001] The utility model relates to a mold structure, in particular to an extrusion-blowing structure. Background Art

[0002] In the existing extrusion blow molding process, the plastic to be blown is squeezed into the mold, and then the blow rod is extended into the mold for blow molding. Since the blowing holes on the blow rod are mostly set at the bottom of the blow needle, the blow needle blows the plastic to be blown downward during blow molding. The plastic to be blown on both sides of the blow hole moves to both sides due to the influence of the blowing. Some small-diameter products with flat shoulders are prone to material accumulation on the neck, affecting filling. Utility Model Content

[0003] The utility model aims to provide an extrusion-blowing structure which can avoid material accumulation in the neck.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solution:

[0005] A blow molding structure includes a blow rod, which includes a cutting ring, a blow needle, a blow needle and a blow needle head. One end of the blow needle is connected to the cutting ring, and the other end of the blow needle is connected to the blow needle head. At least one blow hole is provided on the side wall of the blow needle head. The blow needle passes through the cutting ring, the blow needle and the blow needle head in sequence.

[0006] Preferably, four evenly distributed blowing holes are provided on the side wall of the blowing needle head.

[0007] Preferably, the angle between the axial direction of the blowing hole and the axial direction of the blowing needle head is less than 90°.

[0008] Preferably, the portion of the blow needle close to the blanking ring has a first convex ring, the blanking ring is provided with a first groove, and the first convex ring matches the first groove.

[0009] Preferably, an exhaust groove arranged around the blow needle is opened on the outer wall of the blow needle.

[0010] Preferably, it also includes a shear plate connected to the mold, the shear plate having a first connecting ring and a second connecting ring connected as one piece, the second connecting ring is located above the first connecting ring, the inner diameter of the first connecting ring matches the lower end of the cutting ring, and the inner diameter of the second connecting ring gradually increases from one end close to the first connecting ring to the other end.

[0011] Preferably, a sealing ring is provided at the connection between the blow needle and the blow needle head.

[0012] By adopting the above-mentioned design scheme, the beneficial effects of the utility model are as follows: a blow needle head is provided to be connected to a blow needle, at least one blowing hole is opened on the side wall of the blow needle head, and blow molding is performed using the blowing hole. Since the gas is blown out from the side wall of the blow needle head, it is possible to avoid the accumulation of material on the neck of some small-diameter products with flat shoulders. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic structural diagram of the extrusion blow molding structure of Example 1 of the present utility model;

[0014] Figure 2 This is a schematic structural diagram of the blowing rod of Example 2 of the present utility model;

[0015] Blowing needle a,

[0016] Cutting ring 10,

[0017] Blow needle 20, first convex ring 21, exhaust groove 22,

[0018] Blow needle 30, blow hole 31,

[0019] Shear plate 40, first connecting ring 41, second connecting ring 42,

[0020] Sealing ring 50 , cooling water channel 60 . DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0022] This embodiment uses Figure 1 The directions shown are reference directions for up and down orientations.

[0023] Example 1

[0024] like Figure 1 As shown, an extrusion blow structure includes a blow rod, which includes a cutting ring 10, a blow needle 20, a blow needle a and a blow needle head 30. One end of the blow needle 20 is connected to the cutting ring 10, and the other end of the blow needle 20 is connected to the blow needle head 30. In this embodiment, the blow needle 20 is connected to the cutting ring 10 by a thread, and the blow needle 20 is connected to the blow needle head 30 by a thread.

[0025] In this embodiment, the upper end of the blowing needle a is connected to a connecting rod (not shown in the figure) through a thread, and the connecting rod is used to be connected to the blowing needle holder of the machine.

[0026] At least one blowing hole 31 is provided on the side wall of the blow needle head 30. The blow needle a passes through the cutting ring 10, the blow needle 20 and the blow needle head 30 in sequence. The air outlet of the blow needle a is connected to the inner cavity of the blow needle head 30, and the inner cavity of the blow needle head 30 is connected to the blowing hole 31. In this embodiment, four evenly distributed blowing holes 31 are provided on the side wall of the blow needle head 30.

[0027] As a preferred embodiment of this embodiment, the part of the blowing needle 20 close to the cutting ring 10 has a first convex ring 21, and the cutting ring 10 is provided with a first groove. The first convex ring 21 matches the first groove, that is, the outer diameter of the first convex ring 21 matches the inner diameter of the first groove, so that the center axis of the cutting ring 10 and the center axis of the blowing needle 20 can remain in the same straight line after connection, thereby ensuring the stability of the connection.

[0028] As a preferred embodiment of the present invention, an exhaust groove 22 is provided on the outer wall of the blow needle 20 and is arranged around the blow needle 20. The exhaust groove 22 is located near the first convex ring 21. During extrusion and blow molding, the exhaust groove 22 is located below the sealing section of the product. The exhaust groove 22 helps to exhaust air, so that during the blow molding process, the upper end of the bottle mouth will not have problems such as material shortage or lines due to poor exhaust, which will affect the sealing of the product.

[0029] As a preferred embodiment of this embodiment, it also includes a shear plate 40 connected to the mold, and the shear plate 40 has a first connecting ring 41 and a second connecting ring 42 that are integrally connected. The second connecting ring 42 is located above the first connecting ring 41, and the inner diameter of the first connecting ring 41 matches the lower end of the cutting ring 10, that is, the inner diameter of the first connecting ring 41 is less than or equal to the outer diameter of the cutting ring 10, and is used to fix the blow rod to prevent the cutting ring 10 from being skewed, resulting in eccentricity of the blow needle and affecting the blow molding of the product neck; the inner diameter of the second connecting ring 42 gradually increases from one end close to the first connecting ring 41 to the other end to avoid frequent collisions between the shear plate 40 and the cutting ring 10, causing damage to the cutting ring 10 or the shear plate 40.

[0030] As a preferred embodiment of the present invention, the blowing needle 20 and the cutting ring 10 are provided with cooling water channels 60 that are interconnected. The cooling water channels are used for the circulation of cooling water to cool the blowing needle 20. A sealing ring 50 is provided at the connection between the blowing needle 20 and the blowing needle head 30. By providing the sealing ring 50, on the one hand, leakage of cooling water in the blowing needle 20 can be avoided, and on the other hand, leakage of gas in the blowing needle head 30 can also be avoided.

[0031] Example 2

[0032] like Figure 2As shown, the difference between this embodiment and embodiment 1 is that the angle between the axial direction of the blowing hole 31 and the axial direction of the blowing needle head 30 is less than 90°, that is, the blowing hole 31 is arranged gradually upward from the inside to the outside. During blow molding, the gas is blown out obliquely upward, so that the blowing hole 31 can better solve the bottleneck material accumulation problem.

[0033] In summary, a blow needle head 30 is connected to the blow needle 20, and at least one blowing hole 31 is opened on the side wall of the blow needle head 30. Blow molding is performed using the blowing hole 31. Since the gas is blown out from the side wall of the blow needle head 30, it can avoid the accumulation of material on the neck of some small-diameter products with flat shoulders. The blowing hole 31 is set on the blow needle head 30 instead of on the blow needle 20 because a cooling water channel 60 is required to be opened on the side wall of the blow needle 20.

[0034] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only a specific implementation method of the utility model and is not intended to limit the scope of protection of the utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the utility model should be included in the scope of protection of the utility model.

Claims

1. An extrusion blow molding structure, comprising a blow rod, characterized in that: The blowing rod includes a cutting ring, a blowing needle, a blowing needle and a blowing needle head. One end of the blowing needle is connected to the cutting ring, and the other end of the blowing needle is connected to the blowing needle head. At least one blowing hole is opened on the side wall of the blowing needle head. The blowing needle passes through the cutting ring, the blowing needle and the blowing needle head in sequence.

2. The extrusion blow molding structure according to claim 1, wherein: Four evenly distributed blowing holes are provided on the side wall of the blowing needle head.

3. The extrusion blow molding structure according to claim 1, wherein: The included angle between the axial direction of the blowing hole and the axial direction of the blowing needle head is less than 90°.

4. The extrusion blow molding structure according to claim 1 or 3, wherein: The portion of the blow needle close to the blanking ring has a first convex ring, the blanking ring is provided with a first groove, and the first convex ring matches the first groove.

5. The extrusion blow molding structure according to claim 4, wherein: An exhaust groove arranged around the blow needle is opened on the outer wall of the blow needle.

6. The extrusion blow molding structure according to claim 1, wherein: It also includes a shear plate connected to the mold, the shear plate having a first connecting ring and a second connecting ring connected as one piece, the second connecting ring being located above the first connecting ring, the inner diameter of the first connecting ring matching the lower end of the cutting ring, and the inner diameter of the second connecting ring gradually increasing from one end close to the first connecting ring to the other end.

7. The extrusion blow molding structure according to claim 1, wherein: A sealing ring is provided at the connection between the blow needle and the blow needle head.

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