Injection blow molding device for wide-mouth plastic bottle

Abstract

The utility model discloses a wide-mouth plastic bottle injection blow molding device which comprises a fixed mold base, a movable mold base and a mold core, the fixed mold base and the movable mold base move relatively, and the mold core is arranged in the movable mold base in a penetrating mode and comprises a mold core body and a mold core head. A pair of blow molding half molds is arranged on the movable mold base; the core body is sleeved with an ejection push pipe and an integrated bottleneck ring, at least one pair of connecting rods are arranged on the ejection push pipe in the circumferential direction, connecting rod via holes are formed in the integrated bottleneck ring, the connecting rods penetrate through the corresponding connecting rod via holes and then are provided with limiting protruding parts, a bottleneck cavity is formed between the integrated bottleneck ring and the core body, and the ejection push pipe comprises a pipe body, an annular pushing part is arranged at the top of the pipe body; a pushing through hole is formed in the movable mold base, and the pipe body is arranged in the pushing through hole in a penetrating manner; and a demolding driving device for driving the ejection push pipe to move along the axis direction of the mold core is arranged on the movable mold base. The injection blow molding device disclosed by the utility model is mainly used for injection blow molding of plastic products such as wide-mouth plastic bottles and the like.

Description

Technical Field

[0001] The utility model relates to an injection blow molding device, in particular to an injection blow molding device for a wide-mouth plastic bottle. Background Art

[0002] At present, the molding bottle mouth in the injection molding device of the large-diameter wide-mouth bottle is usually formed by a pair of bottle mouth half-mold inserts. Since the opening and closing of the two bottle mouth half-mold inserts require an independent driving structure, the structure of the entire injection molding device is relatively complicated. In addition, due to the large size of the large-diameter wide-mouth bottle, the corresponding two bottle mouth half-molds are large in size, which are easy to deform during use and require a large clamping force; moreover, the finished product obtained after injection blowing is prone to burrs at the bottle mouth mold seam. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a wide-mouth plastic bottle injection-blow molding device with a compact and simple structure.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is: a wide-mouth plastic bottle injection blow molding device, comprising: a fixed mold seat, a movable mold seat that moves relative to the fixed mold seat, and a core inserted in the movable mold seat, a blow molding mechanism is arranged in the core, and the core comprises: a core body arranged in the movable mold seat, and a core head whose tail is arranged in the core body; an injection mold is arranged on the fixed mold seat, an injection flow channel connected to the injection mold is arranged in the fixed mold seat, and an injection cavity matched with the core head is arranged in the injection mold; a pair of blow molding half molds corresponding to the bottle body of the wide-mouth plastic bottle and a blow molding half mold driving device for driving the pair of blow molding half molds to open and close are arranged on the movable mold seat; an ejection push tube and an integrated bottle mouth ring are sleeved on the core body, and an ejection push tube and an integrated bottle mouth ring are sleeved on the core body. At least one pair of connecting rods is circumferentially arranged on the push tube, and connecting rod through holes corresponding to the connecting rods are provided on the integrated bottle mouth ring. After the connecting rod passes through the corresponding connecting rod through holes, a limiting protrusion is provided. A bottle mouth ring positioning cavity matching with the integrated bottle mouth ring is provided on the movable mold seat, and the integrated bottle mouth ring is movably arranged in the bottle mouth ring positioning cavity of the movable mold seat, and a bottle mouth cavity is provided between the integrated bottle mouth ring and the core body. The ejection push tube comprises: a tube body, a ring-shaped pushing portion matching with the bottle mouth cavity is provided on the top of the tube body, and a pushing step for pushing the integrated bottle mouth ring is formed between the ring-shaped pushing portion and the tube body, and a pushing through hole matching with the tube body is provided on the bottom wall of the bottle mouth ring positioning cavity of the movable mold seat; a demoulding drive device for driving the ejection push tube to move along the axial direction of the core is provided on the movable mold seat.

[0005] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the tube body is provided with a limit mounting boss at its bottom, and a limit mounting boss placement hole is opened in the movable mold base below the push hole, which is communicated with the push hole and cooperates with the limit mounting boss, and a limit step is formed between the limit mounting boss placement hole and the push hole; the connecting rod is arranged on the limit mounting boss.

[0006] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the limiting protrusion is a limiting block, and the specific setting method of the limiting block is: the limiting block is provided with a limiting installation through hole, and the corresponding end face of the connecting rod is provided with a limiting installation threaded hole corresponding to the limiting installation through hole, and a limiting installation screw is selected to pass through the limiting installation through hole on the limiting block and is set in the limiting installation threaded hole on the corresponding connecting rod.

[0007] As a preferred solution, in the wide-mouth plastic bottle injection blow molding device, the one-piece bottle mouth ring is provided with a limit block placement hole connected to the upper part of the connecting rod through hole and matched with the limit block.

[0008] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the core body is provided with a core head movable cavity that matches the core head, and the tail of the core head is movably arranged in the core head movable cavity of the core body; the specific structure of the blow molding mechanism includes: an automatic blowing port closing device is arranged between the core head and the core body, and a blow molding channel communicating with the core head movable cavity is provided in the core body.

[0009] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the specific structure of the automatic closing device for the blow molding port includes: a reset rod arranged on the bottom surface of the core head, and a stepped placement hole is opened on the bottom wall of the core head active cavity on the core body, and the stepped placement hole includes: a reset rod placement hole and a reset component placement hole with successively larger diameters, the reset rod is movably inserted into the reset rod placement hole, the lower end of the reset rod extends into the reset component placement hole, and an elastic reset component and a limit seat are sequentially sleeved from the inside to the outside.

[0010] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the stepped placement hole also includes: a piston mounting hole with a larger diameter than the reset component placement hole and extending outward, and pistons are arranged in the reset component placement hole and the piston mounting hole, that is, the cap portion of the piston is arranged in the piston mounting hole, and the plunger portion of the piston is arranged in the reset component placement hole, and sealing rings are respectively arranged between the cap portion of the piston and the piston mounting hole, and between the plunger portion of the piston and the reset component placement hole, and a push air channel cooperating with the piston is arranged in the movable mold base.

[0011] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the reset component placement hole includes: a thin-diameter section connected to the reset rod placement hole, and a thick-diameter section connected to the piston mounting hole, and the thick-diameter section of the reset component placement hole cooperates with the plunger part of the piston.

[0012] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the specific structure of the demolding drive device includes: at least one pair of ejector rods movably inserted into the movable mold base, the corresponding ends of the ejector rods are connected to the ejection push tubes, the other ends of the ejector rods are connected together through a push plate, and an ejector rod return spring is sleeved on the ejector rods.

[0013] As a preferred solution, in the wide-mouth plastic bottle injection blow molding device, cooling channels are provided on the blow molding half molds.

[0014] As a preferred embodiment, in the wide-mouth plastic bottle injection blow molding device, the blow molding half-mold driving device includes: a pair of blow molding opening and closing cylinders respectively located on the outside of the corresponding blow molding half-molds, the blow molding opening and closing cylinders are arranged on the movable mold base, and the piston rod of the blow molding opening and closing cylinders is connected to the corresponding blow molding half-mold.

[0015] The beneficial effects of the utility model are:

[0016] 1. The utility model reduces the size of the mold, increases the mold strength, prolongs the mold life, and avoids the formation of burrs at the bottle mouth of the molded plastic bottle by setting the bottle mouth ring as an integrated structure.

[0017] 2. The utility model is provided with an ejector push tube, which includes an annular ejector portion matched with the bottle mouth cavity. Therefore, during demolding, the annular ejector portion pushes against the bottle mouth of the wide-mouth bottle in the bottle mouth cavity to eject the wide-mouth bottle from the core head. During the ejection process, the integrated bottle mouth ring will also rise. During the resetting process of the ejector push tube after demolding, the integrated bottle mouth ring returns to its original position under the action of the limit block. The entire demolding process is very simple and reliable.

[0018] 3. The utility model provides a limit block installation hole on the integrated bottle mouth ring, which is connected to the upper part of the connecting rod through hole and matched with the limit block, so that the limit block and the limit installation screw are buried in the limit block installation hole during injection molding and blow molding, which will not affect the installation of the injection mold and the blow mold, making the structure of the entire injection and blow device more compact.

[0019] 4. The utility model provides an automatic blowing port closing device and a blowing channel in the core, so that during ventilation blow molding, the core head extends forward under the action of air pressure, and the blowing port between the core head and the core body is automatically opened. When the blow molding is completed, the air supply is stopped, and the core head automatically resets under the action of the automatic blowing port closing device, closing the blowing port between the core head and the core body. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic cross-sectional structure diagram of the injection mold of the utility model when the mold is closed, viewed from the top.

[0021] Figure 2 It is a schematic cross-sectional structure diagram of the blow mold of the utility model when the mold is closed, viewed from the top.

[0022] Figure 3 It is a schematic cross-sectional structure diagram of the utility model in a demoulding state viewed from above.

[0023] Figure 4 yes Figure 3 Schematic diagram of the enlarged structure of part A.

[0024] Figures 1 to 4 1. The reference numerals in the drawings are: 1. fixed mold base, 12. injection molding runner, 2. injection mold, 21. injection molding cavity, 3. blow molding half mold, 31. cooling hole, 4. blow molding opening and closing cylinder, 5. integrated bottle mouth ring, 55. limit block placement hole, 6. ejector tube, 60. limit mounting boss, 61. tube body, 62. annular ejector portion, 63. ejector step, 64. connecting rod, 65. limit block, 651. limit mounting screw, 66. push plate, 67. ejector rod, 68. ejector rod return spring, 7. core, 70. core body, 70 1. Reset rod placement hole, 702. Reset component placement hole, 703. Piston installation hole, 704. Blow molding channel, 71. Core head, 711. Core head active cavity, 72. Reset rod, 73. Limit nut, 74. Air port reset spring, 78. Piston, 8. Moving mold bracket, 80. Moving mold plate, 804. Blow molding air inlet, 805. Push air duct, 81. Core mounting plate, 82. Push tube mounting plate, 821. Limit mounting boss placement hole, 83. Blow molding mold mounting frame, 831. Bottle mouth ring positioning cavity, 9. Wide-mouth plastic bottle. DETAILED DESCRIPTION

[0025] The specific implementation scheme of the wide-mouth plastic bottle injection blow molding device described in the utility model is described in detail below in conjunction with the accompanying drawings.

[0026] like Figures 1 to 3As shown, a wide-mouth plastic bottle injection blow molding device described in the utility model comprises: a core 7, a fixed mold base 1, and a movable mold base that moves relative to the fixed mold base 1, the core 7 comprises: a core body 70, and a core head 71 whose tail is arranged in the core body 70, and the specific arrangement is: a core head movable cavity 711 that matches the core head 71 is opened on the top of the core body 70, and the tail of the core head 71 is movably arranged in the core head movable cavity 711 of the core body 70; the movable mold base comprises: a movable mold bracket 8, and a movable mold plate 80, a core mounting plate 81, a push tube mounting plate 82 and a blow mold mounting frame 83 that are sequentially arranged on the movable mold bracket 8, the core 7 is arranged on the movable mold plate 80 through the core mounting plate 81 (it belongs to the conventional technology in this field and will not be described in detail here), and the upper part of the core body 70 is penetrated in the push tube mounting plate 82 and the blow mold mounting frame 83; the core 7 is provided with a blow molding mechanism, such as Figure 4As shown, the specific structure of the blow molding mechanism includes: an automatic blowing port closing device arranged between the core head 71 and the core body 70, a blowing channel 704 communicating with the core head active cavity 711 is opened in the core body 70, and a blow molding air inlet 804 connected to the blowing channel 704 is opened on the movable template 80; the automatic blowing port closing device includes: a reset rod 72 arranged on the bottom surface of the core head 71, a stepped placement hole is opened on the bottom wall of the core head active cavity 711, and the stepped placement hole includes: a reset rod placement hole 701 with successively larger diameters, a reset component placement hole 702 and a piston mounting hole 703, the piston mounting hole 703 penetrates the core body 70 outwardly, and the reset rod 72 is movably inserted into the reset rod placement hole 701 In the embodiment, the lower end of the reset rod 72 extends into the reset component placement hole 702, and an air port reset spring 74 as an elastic reset component and a limit nut 73 as a limit seat are sequentially sleeved from the inside to the outside, and the air port reset spring 74 and the limit nut 73 are located in the reset component placement hole 702; a piston 78 is arranged in the reset component placement hole 702 and the piston mounting hole 703, that is: the cap portion of the piston 78 is arranged in the piston mounting hole 703, and the plunger portion of the piston 78 is arranged in the reset component placement hole 702, and sealing rings are respectively arranged between the cap portion of the piston 78 and the piston mounting hole 703, and between the plunger portion of the piston 78 and the reset component placement hole 702 (which belongs to the conventional technology in this field and will not be described in detail here); the movable template 80 is arranged There is a push air channel 805 that cooperates with the piston 78; the fixed mold base 1 is provided with an injection mold 2, the fixed mold base 1 is provided with an injection flow channel 12 connected to the injection mold 2, and the injection mold 2 is provided with an injection cavity 21 that cooperates with the core head 71; the blow mold mounting frame 83 is provided with a pair of blow molding half molds 3 corresponding to the bottle body of the wide-mouth plastic bottle 9, and a blow molding half mold driving device that drives the pair of blow molding half molds 3 to open and close, and the blow molding half mold driving device includes: a pair of blow molding opening and closing cylinders 4 respectively located on the outer sides of the corresponding blow molding half molds 3, the blow molding opening and closing cylinders 4 are arranged on the corresponding sides of the blow mold mounting frame 83, and the piston rod of the blow molding opening and closing cylinder 4 is connected to the corresponding blow molding half mold 3; the core body 7 0 is sleeved with an ejector tube 6 and an integrated bottle mouth ring 5, and at least one pair of connecting rods 64 are evenly arranged on the ejector tube 6 along the circumferential direction, and a connecting rod through hole corresponding to the connecting rod 64 is opened on the integrated bottle mouth ring 5, and a limiting block 65 as a limiting protrusion is arranged after the connecting rod 64 passes through the corresponding connecting rod through hole on the integrated bottle mouth ring 5, and the specific arrangement method of the limiting block 65 is as follows: a limiting installation through hole is opened on the limiting block 65, and a limiting installation threaded hole corresponding to the limiting installation through hole on the limiting block 65 is opened on the corresponding end surface of the connecting rod 64, and a limiting installation screw 651 is selected to pass through the limiting installation through hole on the limiting block 65 and is arranged in the limiting installation threaded hole on the corresponding connecting rod 64 (it belongs to the conventional technology in this field and will not be described in detail here);The one-piece bottle mouth ring 5 is provided with a limit block placement hole 55 connected to the upper part of the connecting rod through hole and matched with the limit block 65, so that the limit block 65 and the limit mounting screw 651 can be hidden therein; the blow mold mounting frame 83 is provided with a bottle mouth ring positioning cavity 831 matched with the one-piece bottle mouth ring 5, and the one-piece bottle mouth ring 5 is movably arranged in the bottle mouth ring positioning cavity 831 of the blow mold mounting frame 83, and a bottle mouth cavity is arranged between the one-piece bottle mouth ring 5 and the core body 70, and the ejection push tube 6 comprises: a tube body 61, a ring-shaped push portion 62 matched with the bottle mouth cavity is arranged on the top of the tube body 61, and a push step 63 for pushing the one-piece bottle mouth ring 5 is formed between the ring-shaped push portion 62 and the tube body 61, and the bottom of the tube body 61 A limited mounting boss 60 is provided, and the connecting rod 65 is provided on the limited mounting boss 60; a push-through hole matching the tube body 61 is provided on the bottom wall of the bottle mouth ring positioning cavity 831 on the blow mold mounting frame 83; a limit mounting boss placement hole 821 communicating with the push-through hole and matching the limited mounting boss 60 is provided in the push-tube mounting plate 82 below the push-through hole, and a limit step is formed between the limit mounting boss placement hole 821 and the push-through hole; a demoulding drive device for driving the ejection push tube 6 to move along the axial direction of the core 7 is provided on the movable mold seat, and the specific structure of the demoulding drive device includes: at least one pair of ejector rods 67 movably penetrated in the movable mold plate 80 and the core mounting plate 81, and the corresponding ends of the ejector rods 67 (; Figures 1 to 3 The upper end of the push rod 67 is connected to the ejection push tube 6, and the other end of the push rod 67 is connected through a push plate 66. The push rod 67 is sleeved with a push rod return spring 68.

[0027] In actual application, the reset component placement hole 702 includes: a thin-diameter section connected to the reset rod placement hole 701, and a thick-diameter section connected to the piston mounting hole 703, and the thick-diameter section of the reset component placement hole 702 cooperates with the plunger portion of the piston 78; the blow molding half mold 3 is provided with a cooling channel including a plurality of cooling holes 31 (which belongs to the conventional technology in this field and will not be described in detail here); and the movable mold base is usually also provided with a power device for driving the push plate 66 to rise (which belongs to the conventional technology in this field and will not be described in detail here).

[0028] In actual use, the blow molding half mold 3 is opened, the movable mold seat is moved closer to the fixed mold seat 1, and the mold closing action is completed. The molten plastic enters the injection mold 2 from the injection runner 12. After being heat-insulated and shaped into a preform, the movable mold seat retreats a certain distance, so that the injection mold 2 leaves the preform. Then, the two blow molding half molds 3 are molded together under the action of a pair of blow molding opening and closing cylinders 4. After the mold is closed, compressed gas is injected into the push air channel 805, so that the piston 78 pushes the reset rod 72 to move upward, and the blowing port between the core body 70 and the core head 71 is opened, so that the compressed gas passes through the blow molding channel 704 from the blow molding inlet 804 and blows out from the blowing port between the core body 70 and the core head 71, so that the preform is blown into shape, and then cooled and shaped to obtain. Wide-mouth plastic bottle 9, then, open the blow molding half mold 3, and then, through the push plate 66, multiple push rods 67 are pushed upward synchronously, and the ejection push tube 6 rises synchronously, and its annular push portion 62 abuts against the end face of the bottle mouth of the wide-mouth plastic bottle 9, and the wide-mouth plastic bottle 9 is ejected from the core 7, and it is taken out manually or by a manipulator. During the ejection process of the wide-mouth plastic bottle 9, the integrated bottle mouth ring 5 will also leave the bottle mouth ring positioning cavity 831 and rise. After demolding is completed, the thrust on the push plate 66 is canceled, and the push plate 66 is reset under the action of the ejector rod reset spring 68. During this process, the limit block 65 is driven by the connecting rod 64 to descend together, so that the integrated bottle mouth ring 5 returns to its position under the action of the limit block 65, and then enters the next production process, and this cycle is repeated.

[0029] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. All equivalent changes and modifications made to the shape, structure, characteristics and spirit described in the scope of the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A wide-mouth plastic bottle injection blow molding device, comprising: A fixed mold seat, a movable mold seat that moves relative to the fixed mold seat, and a core that is inserted into the movable mold seat, wherein a blow molding mechanism is arranged in the core, and the characteristic is that the core comprises: a core body arranged in the movable mold seat, and a core head whose tail is arranged in the core body; an injection mold is arranged on the fixed mold seat, an injection flow channel that is connected to the injection mold is arranged in the fixed mold seat, and an injection cavity that matches the core head is arranged in the injection mold; a pair of blow molding half molds corresponding to the bottle body of the wide-mouth plastic bottle and a blow molding half mold driving device that drives the pair of blow molding half molds to open and close are arranged on the movable mold seat; an ejection push tube and an integrated bottle mouth ring are sleeved on the core body, and at least a pair of connecting rods are arranged circumferentially on the ejection push tube, and the The integrated bottle mouth ring is provided with a connecting rod through hole corresponding to the connecting rod, and a limiting protrusion is provided after the connecting rod passes through the corresponding connecting rod through hole, and a bottle mouth ring positioning cavity matching with the integrated bottle mouth ring is provided on the movable mold seat, and the integrated bottle mouth ring is movably arranged in the bottle mouth ring positioning cavity of the movable mold seat, and a bottle mouth cavity is provided between the integrated bottle mouth ring and the core body, and the ejection push tube comprises: a tube body, and an annular ejection part matching with the bottle mouth cavity is provided on the top of the tube body, and a ejection step for ejecting the integrated bottle mouth ring is formed between the annular ejection part and the tube body, and the movable mold seat is provided with an ejection through hole matching with the tube body on the bottom wall of the bottle mouth ring positioning cavity; and a demoulding drive device for driving the ejection push tube to move along the axial direction of the core is provided on the movable mold seat.

2. The wide-mouth plastic bottle injection blow molding device according to claim 1, characterized in that: The tube body is provided with a limit mounting boss at its bottom, and a limit mounting boss placement hole is opened in the movable mold base at the lower direction of the push hole, which is communicated with the push hole and matched with the limit mounting boss, and a limit step is formed between the limit mounting boss placement hole and the push hole; the connecting rod is arranged on the limit mounting boss.

3. The wide-mouth plastic bottle injection blow molding device according to claim 2, characterized in that: The limiting protrusion is a limiting block, and the specific setting method of the limiting block is: the limiting block is provided with a limiting installation through hole, and the corresponding end face of the connecting rod is provided with a limiting installation threaded hole corresponding to the limiting installation through hole, and a limiting installation screw is selected to pass through the limiting installation through hole on the limiting block and is set in the limiting installation threaded hole on the corresponding connecting rod.

4. The wide-mouth plastic bottle injection blow molding device according to claim 3, characterized in that: The one-piece bottle mouth ring is provided with a limit block placement hole which is connected with the upper part of the connecting rod through hole and matched with the limit block.

5. The wide-mouth plastic bottle injection blow molding device according to claim 1, characterized in that: The core body is provided with a core head movable cavity which matches the core head, and the tail of the core head is movably arranged in the core head movable cavity of the core body; the specific structure of the blow molding mechanism includes: an automatic blowing port closing device is arranged between the core head and the core body, and a blow molding channel which communicates with the core head movable cavity is provided in the core body.

6. The wide-mouth plastic bottle injection blow molding device according to claim 5, characterized in that: The specific structure of the automatic closing device for the blow molding port includes: a reset rod arranged on the bottom surface of the core head, a stepped placement hole is opened on the bottom wall of the core head active cavity on the core body, and the stepped placement hole includes: a reset rod placement hole and a reset component placement hole with successively larger diameters, the reset rod is movably inserted into the reset rod placement hole, the lower end of the reset rod extends into the reset component placement hole, and an elastic reset component and a limit seat are sequentially sleeved from the inside to the outside.

7. The wide-mouth plastic bottle injection blow molding device according to claim 6, characterized in that: The stepped placement hole also includes: a piston mounting hole with a larger diameter than the reset component placement hole and extending outward, and pistons are arranged in the reset component placement hole and the piston mounting hole, that is, the cap portion of the piston is arranged in the piston mounting hole, and the plunger portion of the piston is arranged in the reset component placement hole, and sealing rings are respectively arranged between the cap portion of the piston and the piston mounting hole, and between the plunger portion of the piston and the reset component placement hole; a push air channel cooperating with the piston is arranged in the movable mold base.

8. The wide-mouth plastic bottle injection blow molding device according to claim 7, characterized in that: The reset component placement hole comprises: a thin-diameter section connected to the reset rod placement hole, and a thick-diameter section connected to the piston mounting hole. The thick-diameter section of the reset component placement hole matches the plunger portion of the piston.

9. The wide-mouth plastic bottle injection blow molding device according to claim 1, characterized in that: The specific structure of the demoulding drive device includes: at least one pair of ejector rods movably arranged in the movable mold base, the corresponding ends of the ejector rods are connected to the ejection push tubes, the other ends of the ejector rods are connected together through push plates, and the ejector rods are sleeved with ejector rod reset springs.

10. The wide-mouth plastic bottle injection blow molding device according to claim 1, characterized in that: The blow molding half molds are all provided with cooling channels.

11. A wide-mouth plastic bottle injection blow molding device according to any one of claims 1 to 10, characterized in that: The blow molding half-mold driving device comprises: a pair of blow molding opening and closing cylinders located outside the corresponding blow molding half-molds, the blow molding opening and closing cylinders are arranged on the movable mold seat, and the piston rods thereof are connected to the corresponding blow molding half-molds.

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