Bottle preform stretching mechanism of plastic injection blow molding machine

Abstract

The bottle preform stretching mechanism of the plastic injection-blow molding machine comprises a core rod assembly arranged on a rotating tower, an air pressure stretching mechanism is arranged on the core rod assembly and comprises an air channel integrated plate fixed on the rotating tower, and a pushing air channel, an exhaust air channel and an air blowing air channel are arranged in the air channel integrated plate. The core rod assembly comprises a core rod body and a core rod head, the core rod head is inserted into the core rod body, the core rod body is inserted into the gas circuit integrated plate, an inner cavity is formed in the upper end of the core rod body, the upper end of the core rod head is connected with a piston, the piston is located in the inner cavity and divides the inner cavity into an upper inner cavity and a lower inner cavity, an exhaust hole is formed in the lower inner cavity and communicated with an exhaust gas circuit, and the exhaust gas circuit is communicated with the exhaust gas circuit. The upper inner cavity is communicated with a pushing gas path, the core rod body is further provided with a blowing through hole, the blowing through hole is communicated with a blowing gas path, a reset structure is arranged between the core rod head and the core rod body, the pushing gas path and the blowing gas path are connected with a gas source, the gas path integrated plate is further provided with an exhaust outlet, and the exhaust gas path is communicated with the exhaust outlet.

Description

Technical Field

[0001] The utility model relates to a bottle embryo stretching mechanism of a plastic injection blow molding machine, belonging to the field of plastic machinery. Background Art

[0002] A plastic injection blow molding machine, also known as a one-step plastic hollow container molding machine, is a machine that continuously processes plastic preforms for injection molding and blow molding at separate stations on the same frame to produce hollow plastic containers. Traditional plastic injection blow molding machines utilize a mechanically driven core rod stretching mechanism in the blow molding station. A pneumatic cylinder drives a push plate, which in turn moves (stretches) the core rod. However, due to space limitations in the blow molding station, the push plate's maximum travel is limited to 5mm, significantly limiting the range of products that can be processed. Summary of the Invention

[0003] The purpose of the utility model is to overcome the shortcomings of the existing technology and provide a bottle preform stretching mechanism for a plastic injection blow molding machine, which sets an air path in the core rod and uses air pressure to push the core rod to stretch, thereby greatly increasing the core rod stretching stroke and expanding the processing range.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] The cam is threaded into the air filter, and the cam is threaded into the air filter, and the cam is threaded into the air filter, and the cam is threaded into the air filter, and the cam is threaded into the air filter, and the cam is threaded into the air filter, and the cam is threaded into the air filter, and the cam is threaded into the

[0006] Furthermore, a push air inlet and a blow air inlet are provided in the turret. The push air inlet is connected to the push air path and is connected to an external air source, and the blow air inlet is connected to the blow air path and is connected to an external air source.

[0007] Furthermore, the reset structure includes a counterbore in the core rod body, a reset spring sleeved on the core rod head, the upper end of the reset spring abuts under the piston, and the lower end of the reset spring abuts the bottom of the counterbore.

[0008] Furthermore, the core rod body is provided with a card slot, a card plate is provided on the card slot, and the card plate is connected to the gas path integrated board through screws.

[0009] Furthermore, a connecting rod is provided under the piston, the connecting rod is connected to the upper end of the core rod head by a screw, and the upper end of the return spring is against the bottom of the connecting rod.

[0010] Furthermore, there are 1 to 20 core rod assemblies.

[0011] The beneficial effects of the utility model are:

[0012] By arranging an air path integration plate on the turret, in which a push air path, an exhaust air path and a blowing air path are arranged, the air pressure-driven up and down movement (stretching) of the core rod head and the integrated setting of preform blowing are realized. Compared with traditional mechanical pushing, it occupies less space, and the air pressure-driven core rod head stretching stroke is long, with a maximum stroke of up to 20mm, which greatly increases the range of processing plastic hollow containers and has very beneficial positive effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic structural diagram of the bottle embryo stretching mechanism of the plastic injection blow molding machine of the present utility model;

[0014] Figure 2 yes Figure 1 A local enlarged schematic diagram of point A;

[0015] Figure 3 The utility model is a three-dimensional schematic diagram of a bottle embryo stretching mechanism of a plastic injection blow molding machine. DETAILED DESCRIPTION

[0016] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0017] Example 1, as Figure 1 — Figure 3As shown, a stretching mechanism for a bottle embryo of a plastic injection blow molding machine includes a core rod assembly arranged on a turret 1, a pneumatic stretching mechanism is arranged on the core rod assembly, and the pneumatic stretching mechanism includes an air path integration plate 3 fixed to the turret 1, a push air path 5, an exhaust air path 6 and a blowing air path 7 are arranged in the air path integration plate, the core rod assembly includes a core rod body 10 and a core rod head 11, the core rod head 11 is inserted into the core rod body 10, the core rod body 10 is inserted into the air path integration plate 3, and an inner cavity is arranged in the upper end of the core rod body 10, and the upper end of the core rod head 11 is provided with an inner cavity. The end is connected to the piston 12, which is located in the inner cavity and divides the inner cavity into an upper inner cavity 15 and a lower inner cavity 16. An exhaust hole 17 is provided in the lower inner cavity, and the exhaust hole 17 is connected to the exhaust gas path 6. The upper inner cavity 15 is connected to the pushing gas path 5. A blowing hole 18 is also provided on the core rod body 10, and the blowing hole 18 is connected to the blowing gas path 7. A reset structure is provided between the core rod head 11 and the core rod body 10, and the pushing gas path 5 and the blowing gas path 7 are connected to the air source. An exhaust outlet 19 is also provided on the gas path integrated board 3, and the exhaust gas path 6 is connected to the exhaust outlet 19.

[0018] During operation, turret 1 rotates, driving the core rod assembly and the molded plastic preform 01 from the injection molding station to the blowing station (mold). At this point, the plastic preform 01 has just been injection-molded and is still softened. Air is introduced into air path 5, pushing piston 12 downward. Exhaust path 6 and exhaust outlet 19 remain open, facilitating piston 12's movement. Piston 12 then pulls core rod tip 11 out of core rod body 10, stretching plastic preform 01. Air is then introduced into air path 7, blowing the stretched plastic preform 01 into a hollow plastic container 02 (such as a yogurt bottle). After blowing is complete, core rod tip 11 automatically resets due to the reset mechanism. In the actual structure, sealing rings 03 are provided between the push air path 5, exhaust air path 6, and blowing air path 7 and the core rod body 10 to prevent air from crossing between the air paths.

[0019] This solution integrates the push air path 5, exhaust air path 6, and blow air path 7 into the air path integration plate 3, resulting in a compact structure and small size, facilitating assembly of the mandrel assembly. In particular, the pneumatic push mechanism allows for a long stretching stroke of the mandrel head, with a maximum stroke of 20 mm, significantly expanding the product's processing range.

[0020] Furthermore, a push air inlet 20 and a blow air inlet 21 are provided in the turret 1. The push air inlet 20 is connected to the push air path 5 and is connected to an external air source. The blow air inlet 21 is connected to the blow air path 7 and is connected to an external air source. Since the air path integration plate 3 is fixed on the turret 1 and rotates with the turret, the push air path and the blow air path are connected to the air source through the turret, which is convenient for connecting the air pipes.

[0021] Furthermore, the reset structure includes a countersunk hole 25 in the mandrel body 10, and a reset spring 26 sleeved on the mandrel head 11. The upper end of the reset spring 26 abuts under the piston 12, and the lower end of the reset spring abuts the bottom of the countersunk hole 25. When the plastic bottle preform is stretched, the air supply to the air path stops, and the gas in the upper inner cavity 15 is discharged through the pressure relief valve. The piston loses the negative pressure, and the reset spring acts to drive the mandrel head to automatically rebound and reset.

[0022] Furthermore, a card slot 27 is formed on the core rod body 10, and a card plate 28 is provided on the card slot. The card plate 28 is connected to the gas path integrated board 3 by screws, so that the installation is convenient and reliable.

[0023] Furthermore, a connecting rod 29 is provided under the piston 12, and the connecting rod 29 is connected to the upper end of the core rod head 11 by a screw. The upper end of the return spring is against the connecting rod 29. With the connecting rod, the connection between the piston and the core rod head is facilitated.

[0024] Furthermore, the number of the core rod assemblies is 1-20. In this embodiment, the number of the core rod assemblies is 11, i.e., eleven out of one, and each core rod assembly is stretched and blown synchronously.

[0025] The above-mentioned specific implementation methods are used to illustrate the present invention and are only preferred embodiments of the present invention, rather than limiting the present invention. Within the spirit of the present invention and the scope of protection of the claims, any modifications, equivalent replacements, improvements, etc. made to the present invention shall fall within the scope of protection of the present invention.

Claims

1. A preform stretching mechanism for a plastic injection blow molding machine, comprising a core rod assembly disposed on a turret (1), characterized in that: The mandrel assembly is provided with a pneumatic stretching mechanism, which includes an air path integrated plate (3) fixed on the turret (1), wherein a pushing air path (5), an exhaust air path (6) and a blowing air path (7) are provided in the air path integrated plate, and the mandrel assembly includes a mandrel body (10) and a mandrel head (11), wherein the mandrel head (11) is inserted into the mandrel body (10), and the mandrel body (10) is inserted into the air path integrated plate (3), and an inner cavity is provided in the upper end of the mandrel body (10), and the upper end of the mandrel head (11) is connected to a piston (12), and the piston (12) is located in the inner cavity and The inner cavity is divided into an upper inner cavity (15) and a lower inner cavity (16), an exhaust hole (17) is provided in the lower inner cavity, the exhaust hole (17) is connected to the exhaust gas path (6), the upper inner cavity (15) is connected to the push gas path (5), a blowing hole (18) is further provided on the core rod body (10), the blowing hole (18) is connected to the blowing gas path (7), a reset structure is provided between the core rod head (11) and the core rod body (10), the push gas path (5) and the blowing gas path (7) are connected to the gas source, an exhaust outlet (19) is further provided on the gas path integrated board (3), and the exhaust gas path (6) is connected to the exhaust outlet (19).

2. The preform stretching mechanism for a plastic injection blow molding machine according to claim 1, characterized in that The turret (1) is provided with a push air inlet (20) and a blow air inlet (21), the push air inlet (20) is connected to the push air path (5) and is connected to an external air source, and the blow air inlet (21) is connected to the blow air path (7) and is connected to an external air source.

3. The preform stretching mechanism for a plastic injection blow molding machine according to claim 1, characterized in that The reset structure includes a reaming hole (25) provided in the core rod body (10), a reset spring (26) sleeved on the core rod head (11), the upper end of the reset spring (26) abutting against the bottom of the piston (12), and the lower end of the reset spring abutting against the bottom of the reaming hole (25).

4. The preform stretching mechanism for a plastic injection blow molding machine according to claim 1, characterized in that A clamping groove (27) is formed on the core rod body (10), a clamping plate (28) is provided on the clamping groove, and the clamping plate (28) is connected to the gas path integrated plate (3) via screws.

5. The preform stretching mechanism for a plastic injection blow molding machine according to claim 1, characterized in that A connecting rod (29) is provided under the piston (12), the connecting rod (29) is connected to the upper end of the core rod head (11) by a screw, and the upper end of the return spring is against the bottom of the connecting rod (29).

6. The preform stretching mechanism for a plastic injection blow molding machine according to claim 1, characterized in that There are 1 to 20 core rod assemblies.

Images