CN113733522B

CN113733522B - Stretching mechanism of plastic bottle preform for plastic bottle injection mold

Info

Publication number: CN113733522B
Application number: CN202111185706.6A
Authority: CN
Inventors: 李泰然
Original assignee: Shandong Zhenxing Plastic Co ltd
Current assignee: Shandong Zhenxing Plastic Co ltd
Priority date: 2021-10-12
Filing date: 2021-10-12
Publication date: 2023-06-30
Anticipated expiration: 2041-10-12
Also published as: CN113733522A

Abstract

The invention discloses a stretching mechanism of a plastic bottle preform for a plastic bottle injection mold, which relates to the technical field of molds and comprises a blow molding mold, a supporting block and a clamping block, wherein the blow molding mold comprises a mold body and a cavity formed in the side wall of the mold body, the inner wall of the clamping block is provided with a stretching mechanism, the supporting mechanism is arranged at the top end of the supporting block below the clamping block, and an auxiliary blanking mechanism is arranged below the side wall of the mold body in the cavity. The invention effectively solves the problem that the bottom end of a bottle blank is easy to damage due to the small stretching action area of the stretching pipe of the plastic bottle injection mold by arranging the stretching mechanism, the transmission mechanism and the driving mechanism, and effectively solves the technical problem that the material center in the collecting box is easy to be accumulated when the mold is discharged by arranging the supporting mechanism and the auxiliary discharging mechanism.

Description

Stretching mechanism of plastic bottle preform for plastic bottle injection mold

Technical Field

The invention relates to the technical field of molds, in particular to a stretching mechanism of a plastic bottle preform for a plastic bottle injection mold.

Background

In the manufacturing process of the plastic bottle, thermoplastic resin is required to be melted at 228 ℃, then the plastic bottle is subjected to primary blowing through a die, so that a tubular bottle blank is obtained, a supporting ring is arranged at the upper port of the bottle blank, threads are formed at the upper port, when the bottle blank is required to be blown, the bottle blank is required to be heated to about 118 ℃, at the moment, the bottle body is softened to have deformation capacity, then the bottle blank is placed in a split die, the supporting effect on the blowing process is achieved through the limiting effect of the supporting ring and the die, the top end of the bottle blank is stretched to the bottom end of a die cavity through a stretching tube after the die is closed, then low-pressure air is fused, so that the bottle blank is firstly expanded, then high-pressure air is introduced, the bottle blank is immediately expanded to be tightly attached to the inner wall of the die, and the outer wall of the plastic bottle is cooled and demoulded after the outer wall of the plastic bottle is contacted with the inner wall of the die because of the die, and the plastic bottle with a cavity is obtained.

In the prior art, a stretching pipe is needed in the stretching process of the bottle blank, the stretching pipe is generally made of metal, the inside of the stretching pipe is hollow, and the stretching pipe is connected with an external air supply system through an air inlet, so that the blow molding function of the bottle blank can be realized, but the stretching pipe only depends on the outer ring at the bottom end of the stretching pipe to stretch, so that the stress area is small, the bottom end of the bottle blank is easy to damage, and the higher reject ratio is caused; meanwhile, the stretching pipe is also compatible with the subsequent blow molding process when the bottle blank is propped and stretched, so that the stretching pipe needs to be moved back to one end for a distance after the bottle blank is propped and stretched to a certain position, thereby facilitating the outflow of internal gas, in the process, a complex control system is needed to be designed for controlling the bottle blank, the propping and stretching time is needed to be determined according to the situation, otherwise, the stretched part of the bottle blank is rebounded due to the toughness of the bottle blank, and the defective rate of products is further improved; secondly, the bottle blank is supported by the support ring in the blowing process, and although the hardness of the support ring can support the bottle blank for blowing, the situation that the support ring is broken is unavoidable, and improvement is needed; finally, the blanking mode of the plastic bottle die falls into the collecting box below through the gravity of the bottle body, the mode is simple and quick, but a plurality of plastic bottles fall in the same position, and the plastic bottles in the collecting box can be accumulated in the middle, so that the plastic bottles are uniformly distributed through manual work or other mechanical devices, the production cost and the labor are increased, and improvement is needed.

Disclosure of Invention

Based on the technical scheme, the invention aims to provide a stretching mechanism of a plastic bottle preform for a plastic bottle injection mold, so as to solve the technical problems that the existing plastic bottle injection mold is small in stretching pipe stretching action area and the center of materials in a collecting box is easy to accumulate during mold discharging.

In order to achieve the above purpose, the present invention provides the following technical solutions: the stretching mechanism of the plastic bottle preform for the plastic bottle injection mold comprises a blow molding mold body and a cavity arranged on the side wall of the mold body, wherein the stretching mechanism is arranged on the inner wall of the clamping block, the supporting mechanism is arranged at the top end of the supporting block below the clamping block, and the auxiliary blanking mechanism is arranged below the side wall of the mold body positioned in the cavity;

the stretching mechanism comprises a stretching pipe which is slidably connected with the inner wall of the clamping block, a plurality of groups of air outlets are formed in the outer wall of the stretching pipe, a top stretching block is arranged in the bottom wall of the stretching pipe, a transmission mechanism is arranged in the side wall of the stretching pipe and comprises rack plates, a driving mechanism is arranged above the top stretching block and positioned on the side wall of the stretching pipe, the driving mechanism comprises a driving gear, and the supporting mechanism comprises an arc plate positioned at the top end of the supporting block.

Through adopting above-mentioned technical scheme, can realize the top of persistence through stretching mechanism and stretch to play the effect that prevents that the bottle embryo lateral wall from rebounding, supporting mechanism has effectively alleviateed the bottle embryo simultaneously and has only relied on the mode that the support ring supported, plays the effect that the protection shared support ring supported pressure, and the design of supplementary unloading mechanism can make fashioned plastic bottle can be even drop in the collecting box, thereby plays and prevents the accumulational effect in plastic bottle center.

The invention is further characterized in that the top end of the clamping block is provided with a mounting disc, the clamping block is rotationally connected with the mounting disc through a bearing, the blow molding die consists of two groups of die bodies, one end of the blow molding die is provided with a rotating seat, and the two groups of die bodies are rotationally connected with the rotating seat through rotating shafts.

By adopting the technical scheme, the clamping block can rotate; the effect of opening the die body is achieved.

The invention is further characterized in that the top end of the stretching pipe is provided with air injection holes, the air injection holes are connected with an external pneumatic pump through air pipes, the number of the air outlets is multiple, the multiple groups of air outlets are distributed on the outer wall of the stretching pipe at equal intervals, the inner wall of the stretching pipe is connected with a piston in a sliding manner, and a cavity is formed in the stretching pipe.

Through adopting above-mentioned technical scheme for the atmospheric pressure of external pneumatic pump can be through the inside of gas injection hole input stretching pipe, plays the effect that provides the blowing pressure to subsequent blowing operation, and the design of multiunit gas outlet makes the high pressure can be full of the bottle embryo fast, and then realizes the effect of inflation design.

The invention is further characterized in that grooves are arranged in the bottom wall of the stretching pipe, a plurality of groups of the jacking and stretching blocks are arranged in the grooves, the jacking and stretching blocks are circularly distributed in the bottom wall of the stretching pipe, the outer walls of the jacking and stretching blocks are arc side walls, and the unfolding diameters of the jacking and stretching blocks are slightly larger than the diameter of bottle blanks.

Through adopting above-mentioned technical scheme for the top stretches the piece and can not influence the tensile pipe and go deep into the bottle embryo, the expansion diameter that the piece was stretched in the top slightly is greater than the diameter of bottle embryo and can play and carry out the extension of certain degree to bottle embryo bottom lateral wall, thereby is convenient for reduce the degree of difficulty of follow-up bottom blow molding.

The invention is further characterized in that a power gear is arranged in the inner wall of the stretching pipe at one side of the rack plate, the power gear is connected with the rack plate through gear engagement, the power gear is rotationally connected with the inner wall of the stretching pipe through a bearing, a driven gear is connected with the bottom end of the power gear through gear engagement, one end of the driven gear is fixedly connected with a driving turntable, and the outer wall of the driving turntable is connected with a driving belt.

By adopting the technical scheme, the power transmission effect is achieved.

The invention is further characterized in that a driven turntable is arranged below the driven gear on the inner side of the driving belt, one end of the driven turntable is fixedly connected with the driving gear through a coupling, a rotating gear is connected below one side of the driving gear through gear engagement, the rotating gear is fixedly connected with the jacking block through a fixed shaft, a torsion spring is arranged at one end of the rotating gear, and the torsion spring is fixedly connected with the inner wall of the stretching pipe.

Through adopting above-mentioned technical scheme for drive mechanism, actuating mechanism mutually support can drive the top and stretch the piece and expand, and the design of torsional spring makes the top stretch the piece and can automatic re-setting under the condition that does not need external force.

The invention is further arranged that the end face of the arc plate is provided with an arc groove, and the outer wall of the clamping block is provided with a sliding block matched with the inner wall of the arc groove.

Through adopting above-mentioned technical scheme, drive the pivoted effect of block when playing the slider slip.

The auxiliary blanking mechanism comprises a placing groove arranged on the side wall of the die body, rubber hoses are rotatably connected in the placing groove through bearings, the number of the rubber hoses is two, the bottom end of one group of the rubber hoses is provided with an adjusting gear, the bottom end of the rubber hose is fixedly connected with the top end of the adjusting gear, the bottom end of the other group of the rubber hoses is fixedly connected with a connecting shaft, and the bottom end of the connecting shaft is fixedly connected with the top end of the adjusting gear.

Through adopting above-mentioned technical scheme for two sets of rubber hose can produce irregular guide effect to the bottle of decline, and then play and prevent the accumulational effect in collection box center.

The invention is further characterized in that one end of the adjusting gear is provided with an arc rack penetrating into the die body, the arc rack is connected with the adjusting gear through gear engagement, one end of the arc rack is fixedly connected with the side wall of the die body, and the arc rack is in sliding connection with the inner wall of the die body.

By adopting the technical scheme, the circular arc rack drives the adjusting gear to rotate, so that the unfolding and closing effects of the rubber hose are realized.

In summary, the invention has the following advantages:

the invention is characterized in that a stretching mechanism, a transmission mechanism and a driving mechanism are arranged, a stretching tube is extruded by an external pneumatic cylinder and inserted into the bottle blank, so that the bottom end of the stretching tube is higher than the bottom end of the bottle blank, then an external pneumatic pump supplies low pressure, low-pressure air is introduced into a cavity in the stretching tube through an air injection hole, the air pressure gradually increases along with the air pressure in the cavity, the air pressure can push a piston to move downwards on the inner wall of the stretching tube, at the moment, a rack plate can move downwards along with the piston, in the process, the rack plate can drive a power gear to rotate, the power gear drives a driven gear to rotate through the meshing action of a gear, the driven gear drives a driving turntable to rotate after the driven gear rotates, the driven turntable drives a driving gear to rotate after the driving turntable rotates, the driven turntable drives a driving gear to rotate through the meshing action of the gear, the rotating gear drives the top stretching block to rotate through the fixed shaft, the top stretching block gradually rotates outwards to be unfolded, the torsion spring connected with the inner wall of the stretching pipe at one end of the top stretching block is in a force accumulation state, after the top stretching block is completely unfolded, the top stretching block not only can squeeze the bottom side wall of the bottle blank to be outwards stretched for a certain distance, the pre-treatment of blow molding of the bottom side wall of the bottle blank is achieved, the direct and rapid molding of the subsequent bottom side wall is facilitated, the bottom end of the top stretching block forms a round surface after the top stretching block is unfolded, the contact area between the top stretching block and the bottom end of the bottle blank is improved, then the stretching pipe continuously extrudes the stretching pipe downwards through the top stretching block at the bottom, the bottle blank side wall is stretched, necessary stretching operation is provided for the subsequent blow molding, the external air pump stops working after the blow molding process is finished, the gas pressure acting on the piston disappears, the action of torsion spring reset elastic force can enable the rotating gear to rotate reversely, and then the rotating gear drives the top stretching block to rotate reversely to the groove of the bottom wall of the stretching tube to achieve reset, meanwhile, the rotating gear rotates reversely can drive the driving gear to rotate reversely, and then the driving gear drives the driven gear to rotate reversely through the action of the driven turntable, the driving belt and the driving turntable, the driven gear rotates reversely so as to drive the power gear to rotate reversely, the rack plate is driven to move upwards after the power gear rotates reversely, the rack plate drives the piston to move upwards to achieve reset, in the process, the circular surface formed by the expanded multiple groups of top stretching blocks increases the contact area of the top stretching block and the bottom end of the bottle embryo, the acting force of the top stretching block when the top stretching block is used for stretching the bottle embryo can be uniformly distributed on the multiple groups of top stretching blocks, meanwhile, the bottle embryo stress is also uniform, the bottom wall of the bottle embryo is not easily damaged, the qualification rate of a product is improved, further, the side wall of the top stretching block is in a circular arc shape and the texture is smooth, the side wall of the bottle embryo is not produced when the top stretching block rotates gradually to a horizontal state, the stretched blank side wall is not stretched to a certain extent, the stretched blank bottom wall of the bottle embryo is not stretched, the bottom wall of the bottle embryo is not stretched easily is stretched, and the bottom of the bottle embryo is not stretched easily is stretched, and the bottom of the bottle embryo is easily is stretched, and the bottom by the bottom of the bottle embryo is stretched, and the bottle bottom is easily is stretched, and the bottle bottom of the bottle is easily is stretched;

according to the invention, the supporting mechanism and the auxiliary blanking mechanism are arranged, when the external pneumatic cylinder drives the clamping block to move downwards, the sliding block on the outer wall of the clamping block can move into the circular arc plate, and the sliding block drives the clamping block to rotate under the guiding action of the circular arc groove on the end face of the circular arc plate, so that the clamping block is clamped and fixed with the bottle embryo port through the screw thread action, thereby sharing the blow molding pressure born by the supporting ring, avoiding unqualified products caused by the cracking of the supporting ring and causing economic loss; after the blow molding of plastic bottle is accomplished to the blowing mould, open the mould body, the circular arc rack that is located mould body one side at this moment follows the mould body and removes, the circular arc rack can drive adjusting gear through gear engagement effect and rotate, then can directly drive the rubber hose and rotate out the standing groove after the inside adjusting gear of a set of mould body rotates, then can drive the rubber hose through the connecting axle and rotate out the standing groove after the inside adjusting gear of second group mould body rotates, can collide with the plastic bottle through gravity unloading after two sets of rubber hose exhibition, because rubber hose has elasticity, therefore the plastic tubing can carry out irregular unloading, and then can make plastic bottle evenly distributed in external collecting box, the problem is piled up at the collecting box center in subsequent handling has been avoided, production cost has also been practiced thrift in the time of using manpower sparingly, the technical problem that material center pile up in the collecting box is led to easily when effectively having solved the mould ejection of compact.

Drawings

FIG. 1 is a schematic three-dimensional structure of the present invention;

FIG. 2 is a schematic drawing of a stretched tube structure of the present invention;

FIG. 3 is a schematic view of the internal structure of the stretch tube according to the present invention;

fig. 4 is an enlarged view of a portion of fig. 3 according to the present invention.

FIG. 5 is an enlarged view of a portion of the invention at B in FIG. 3;

FIG. 6 is a schematic view of the bottom structure of the stretch tube of the present invention;

FIG. 7 is a schematic diagram of a piston structure according to the present invention;

FIG. 8 is a schematic view of a top extension block according to the present invention;

FIG. 9 is a side view of a guide plate of the present invention;

fig. 10 is a schematic view of the internal structure of the die body according to the present invention.

In the figure: 1. a blow molding die; 101. a die body; 102. a cavity; 2. a support block; 3. a clamping block; 4. a stretching mechanism; 401. stretching the tube; 402. an air outlet; 403. a cavity; 404. a piston; 405. a top extension block; 5. a transmission mechanism; 501. rack plate; 502. a power gear; 503. a driven gear; 504. a driving turntable; 505. a drive belt; 506. a driven turntable; 6. a driving mechanism; 601. a drive gear; 602. rotating the gear; 603. a torsion spring; 604. a fixed shaft; 7. a support mechanism; 701. an arc plate; 702. a slide block; 703. an arc-shaped groove; 8. an auxiliary blanking mechanism; 801. a placement groove; 802. a rubber hose; 803. an adjusting gear; 804. arc racks; 805. and a connecting shaft.

Description of the embodiments

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

Hereinafter, an embodiment of the present invention will be described in accordance with its entire structure.

The drawing mechanism for the plastic bottle preform for the plastic bottle injection mold comprises a blow molding mold 1, a supporting block 2 and a clamping block 3, wherein the blow molding mold 1 comprises a mold body 101 and a cavity 102 arranged on the side wall of the mold body 101, the inner wall of the clamping block 3 is provided with a drawing mechanism 4, the top end of the supporting block 2 is provided with a supporting mechanism 7 below the clamping block 3, the side wall of the mold body 101 is provided with an auxiliary blanking mechanism 8 below the cavity 102, the auxiliary blanking mechanism 8 comprises a placing groove 801 arranged on the side wall of the mold body 101, the inside of the placing groove 801 is rotationally connected with rubber hoses 802 through bearings, the number of the rubber hoses 802 is two, the bottom end of one group of the rubber hoses 802 is provided with an adjusting gear 803, the bottom end of the rubber hose 802 is fixedly connected with the top end of the adjusting gear 803, the bottom end of the other group of rubber hoses 802 is fixedly connected with a connecting shaft 805, the bottom end of the connecting shaft 805 is fixedly connected with the top end of the adjusting gear 803, the rubber hoses 802 can be conveniently unfolded and closed, one end of the adjusting gear 803 is provided with an arc rack 804 penetrating into the die body 101, the arc rack 804 is connected with the adjusting gear 803 through gear engagement, one end of the arc rack 804 is fixedly connected with the side wall of the die body 101, the arc rack 804 is slidably connected with the inner wall of the die body 101, when the die body 101 moves, the arc rack 804 positioned on one side of the die body 101 moves along with the die body 101, at the moment, the arc rack 804 drives the adjusting gear 803 to rotate through gear engagement, the adjusting gear 803 in the die body 101 directly drives the rubber hoses 802 to rotate out of the placing grooves 801 after rotating, after the adjusting gear 803 in the second group of the die body 101 rotates, the rubber hose 802 is driven to rotate out of the placing groove 801 through the connecting shaft 805, and after the two groups of the rubber hoses 802 are unfolded, collision can be generated with the plastic bottles to be discharged, and the plastic tubes can be discharged irregularly due to the elasticity of the rubber hoses 802, so that the plastic bottles can be uniformly distributed in an externally connected collecting box;

the stretching mechanism 4 comprises a stretching tube 401 which is in sliding connection with the inner wall of the clamping block 3, a plurality of groups of air outlets 402 are formed in the outer wall of the stretching tube 401, a jacking block 405 is arranged in the bottom wall of the stretching tube 401, a transmission mechanism 5 is arranged in the side wall of the stretching tube 401, the transmission mechanism 5 comprises a rack plate 501, a power gear 502 is arranged in the inner wall of the stretching tube 401 on one side of the rack plate 501, the power gear 502 is connected with the rack plate 501 through gear engagement, the power gear 502 is rotationally connected with the inner wall of the stretching tube 401 through a bearing, the bottom end of the power gear 502 is connected with a driven gear 503 through gear engagement, one end of the driven gear 503 is fixedly connected with a driving turntable 504, the outer wall of the driving turntable 504 is connected with a transmission belt 505, the rack plate 501 drives the power gear 502 to rotate when moving along with a piston 404, the power gear 503 is driven to rotate through gear engagement after the rotation of the power gear 502, the driven gear 503 rotates to drive the driving turntable 504 to rotate, the driving mechanism 6 is arranged above the top extension block 405 on the side wall of the stretching tube 401, the driving mechanism 6 comprises a driving gear 601, the supporting mechanism 7 comprises a circular arc plate 701 arranged at the top end of the supporting block 2, the end surface of the circular arc plate 701 is provided with a circular arc groove 703, the outer wall of the clamping block 3 is provided with a sliding block 702 matched with the inner wall of the circular arc groove 703, the inner wall of the clamping block is provided with a clamping groove matched with the bottle embryo port, the inner wall of the clamping groove is provided with a thread wall matched with the bottle embryo port thread, when the clamping block 3 moves downwards, the sliding block 702 on the outer wall of the clamping block 3 moves into the circular arc plate 701, and the sliding block 702 drives the clamping block 3 to rotate under the guiding action of the circular arc groove 703 on the end surface of the circular arc plate 701, and the clamping block 3 is clamped and fixed with the bottle embryo port through the thread effect, and further sharing the blow molding pressure born by the support ring.

Referring to fig. 1, a mounting plate is disposed at the top end of the clamping block 3, the clamping block 3 is rotatably connected with the mounting plate through a bearing, the blow molding mold 1 is composed of two sets of mold bodies 101, a rotating seat is disposed at one end of the blow molding mold 1, the two sets of mold bodies 101 are rotatably connected with the rotating seat through a rotating shaft, rotation of the clamping block 3 is facilitated, and mold opening and closing of the mold bodies 101 are facilitated.

Referring to fig. 2 and 3, an air injection hole is formed in the top end of the stretching tube 401, the air injection hole is connected with an external air pressure pump through an air pipe, the number of air outlets 402 is multiple, the multiple groups of air outlets 402 are distributed on the outer wall of the stretching tube 401 at equal intervals, a piston 404 is slidably connected with the inner wall of the stretching tube 401, a cavity 403 is formed in the stretching tube 401, the external air pressure pump is connected with the air injection hole through a connecting pipe, then low-pressure air is injected, after the bottle blank is expanded, high pressure is introduced, the bottle blank is expanded to the inner wall of the cavity 102 at one time to finish shaping, a channel for air circulation in the blowing process of the air outlets 402 is formed, the piston 404 can move on the inner wall of the stretching tube 401, and air pressure pushing the piston 404 is formed in the cavity 403 conveniently.

Referring to fig. 3 and 6, a groove is disposed in the bottom wall of the stretching tube 401, multiple groups of top stretching blocks 405 are disposed in the groove, multiple groups of top stretching blocks 405 are circularly distributed in the bottom wall of the stretching tube 401, the outer walls of the multiple groups of top stretching blocks 405 are arc-shaped side walls, the expanding diameters of the multiple groups of top stretching blocks 405 are slightly larger than those of the bottle blanks, the multiple groups of top stretching blocks 405 are expanded to form round surfaces, the contact area with the bottom ends of the bottle blanks is increased, acting force when the top stretching blocks 405 stretch the bottle blanks can be uniformly distributed on the multiple groups of top stretching blocks 405, meanwhile, the bottle blank stress is also uniform, the bottom wall of the bottle blanks is not easily damaged, the qualification rate of products is improved, further, the diameter of the multiple groups of the top stretching blocks 405 is slightly larger than the diameter of the bottle blanks, the side walls of the top stretching blocks 405 are arc-shaped and smooth, the top stretching blocks 405 do not scratch the side walls of the bottle blanks when gradually rotating to a horizontal state, the expanded top stretching blocks 405 stretch the bottom walls of the bottle blanks to a certain extent, and the top stretching blocks 405 stretch the bottom walls of the bottle blanks to a certain extent, so that the top stretching blocks 405 stretch the bottom walls of the bottle blanks, and the top stretching the bottle blanks, and the bottom walls of the bottle blanks are simultaneously and the bottom wall of the bottle blanks can be expanded to expand rapidly and expand.

Referring to fig. 5 and 8, a driven turntable 506 is mounted below a driven gear 503 on the inner side of a driving belt 505, one end of the driven turntable 506 is fixedly connected with a driving gear 601 through a coupling, a rotating gear 602 is connected under one side of the driving gear 601 through gear engagement, the rotating gear 602 is fixedly connected with a top extension block 405 through a fixing shaft 604, a torsion spring 603 is mounted at one end of the rotating gear 602, the torsion spring 603 is fixedly connected with the inner wall of a stretching tube 401, the driving turntable 504 drives the driven turntable 506 to rotate through the driving belt 505 after rotating, the driven turntable 506 drives a driving gear 601 to rotate after rotating, the driving gear 601 drives the rotating gear 602 to rotate through gear engagement, and the rotating gear 602 drives the top extension block 405 to rotate through the fixing shaft 604, so that the torsion spring 603 starts to store power.

The working principle of the invention is as follows: firstly, placing bottle blanks to be blow molded on the inner sides of two groups of mold bodies 101, realizing the first-step limiting fixation through a supporting ring and a supporting block 2 at the end opening of the bottle blanks, then closing the two groups of mold bodies 101, driving a clamping block 3 to move downwards through an external pneumatic cylinder, enabling a sliding block 702 on the outer wall of the clamping block 3 to move into an arc plate 701, driving the clamping block 3 to rotate under the guiding action of an arc groove 703 at the end surface of the arc plate 701 by the sliding block 702, and further enabling the clamping block 3 to be clamped and fixed with the threads at the end opening of the bottle blanks through the action of threads, so as to share the effect of bearing blow molding pressure by the supporting ring, and avoiding unqualified products caused by breakage of the supporting ring;

then the stretching tube 401 is extruded by an external pneumatic cylinder to be inserted into the bottle blank, the bottom end of the stretching tube 401 is higher than the bottom end of the bottle blank, then an external pneumatic pump is used for supplying low pressure, the low pressure air is introduced into a cavity in the stretching tube 401 through an air injection hole, the air pressure gradually increases along with the air pressure in the cavity, the piston 404 is pushed to move downwards on the inner wall of the stretching tube 401, at the moment, the rack plate 501 moves downwards along with the piston 404, in the process, the rack plate 501 drives the power gear 502 to rotate through the gear meshing action, the power gear 502 drives the driven gear 503 to rotate through the gear meshing action after rotating, the driven gear 503 drives the driving turntable 504 to rotate after rotating, and the driving turntable 504 drives the driven turntable 506 to rotate through a driving belt 505 to realize the power transfer action;

the driven turntable 506 drives the driving gear 601 to rotate after rotating, the driving gear 601 drives the rotating gear 602 to rotate through the gear meshing effect after rotating, the rotating gear 602 drives the jacking block 405 to rotate through the fixed shaft 604, the jacking block 405 gradually rotates outwards to be unfolded, one end of the jacking block 405 is in a force storage state with a torsion spring 603 connected with the inner wall of the stretching pipe 401, when the jacking block 405 is completely unfolded, the unfolding diameter of the jacking block 405 is slightly larger than the diameter of a bottle embryo, so that the jacking block 405 not only can squeeze the bottom side wall of the bottle embryo to be outwards stretched for a certain distance, but also the pre-treatment effect on the blow molding of the bottom side wall of the bottle embryo is achieved, meanwhile, the contact area between the jacking block 405 and the bottom end of the bottle embryo can be improved, the acting force generated when the stretching pipe 401 stretches the bottle embryo can be uniformly distributed on a plurality of groups of jacking blocks 405, meanwhile, the bottom wall of the bottle embryo is not easily damaged, and the qualification rate of products is improved;

then the stretching tube 401 is continuously extruded downwards through an external pneumatic cylinder, the stretching tube 401 stretches the bottle blank through a top stretching block 405 at the bottom, the side wall of the bottle blank is stretched, necessary stretching operation is provided for subsequent blow molding, after the blow molding process is finished, an external air pump stops working, the air pressure acting on a piston 404 disappears, at the moment, the action of restoring elasticity of a torsion spring 603 can enable a rotating gear 602 to rotate reversely, the rotating gear 602 drives the top stretching block 405 to rotate reversely into a groove in the bottom wall of the stretching tube 401 to reset, meanwhile, the rotating gear 602 rotates reversely and drives a driving gear 601 to rotate reversely, the driving gear 601 drives a driven gear 503 to rotate reversely through the actions of a driven turntable 506, a transmission belt 505 and a driving turntable 504, the driven gear 503 rotates reversely, so that a power gear 502 is driven to rotate reversely, a rack plate 501 moves upwards after the power gear 502 rotates reversely, and the rack plate 501 drives the piston 404 to move upwards to reset;

after the blow molding of plastic bottles is completed by the blow molding die, the die body 101 is opened, at the moment, the arc rack 804 positioned at one side of the die body 101 moves along with the die body 101, the arc rack 804 drives the adjusting gear 803 to rotate through the gear engagement effect, the adjusting gear 803 in one group of die bodies 101 directly drives the rubber hose 802 to rotate out of the placing groove 801 after rotating, the adjusting gear 803 in the second group of die bodies 101 drives the rubber hose 802 to rotate out of the placing groove 801 through the connecting shaft 805 after rotating, the two groups of rubber hoses 802 collide with plastic bottles which are fed by gravity after being exhibited, and the plastic tubes can be irregularly fed due to the elasticity of the rubber hoses 802, so that the plastic bottles are uniformly distributed in an externally connected collecting box, and the problem of center accumulation of the collecting box after subsequent treatment is avoided;

when two groups of die bodies 101 are closed, the circular arc racks 804 correspondingly move towards the inside of the die bodies 101, and then the circular arc racks 804 drive the adjusting gears 803 to reversely rotate, so that the adjusting gears 803 drive the rubber hose 802 to move to the inside of the placing groove 801 to finish storage, and the tightness of the die bodies 101 during die closing is ensured.

Although embodiments of the invention have been shown and described, the detailed description is to be construed as exemplary only and is not limiting of the invention as the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples, and modifications, substitutions, variations, etc. may be made in the embodiments as desired by those skilled in the art without departing from the principles and spirit of the invention, provided that such modifications are within the scope of the appended claims.

Claims

1. The utility model provides a stretching mechanism of plastic bottle embryo for plastic bottle injection mold, includes blowing mould (1), supporting shoe (2) and block (3), blowing mould (1) are including mould body (101) and the die cavity that is located mould body (101) lateral wall and offers, its characterized in that: the inner wall of the clamping block (3) is provided with a stretching mechanism (4), the top end of the supporting block (2) below the clamping block (3) is provided with a supporting mechanism (7), and the side wall of the die body (101) is provided with an auxiliary blanking mechanism (8) below the die cavity;

the stretching mechanism (4) comprises a stretching pipe (401) which is slidably connected with the inner wall of the clamping block (3), a plurality of groups of air outlets (402) are formed in the outer wall of the stretching pipe (401), a top stretching block (405) is arranged in the bottom wall of the stretching pipe (401), a transmission mechanism (5) is arranged in the side wall of the stretching pipe (401), the transmission mechanism (5) comprises a rack plate (501), a driving mechanism (6) is arranged above the top stretching block (405) on the side wall of the stretching pipe (401), the driving mechanism (6) comprises a driving gear (601), and the supporting mechanism (7) comprises an arc plate (701) arranged at the top end of the supporting block (2);

the top of tensile pipe (401) has seted up the gas injection hole, and the gas injection hole passes through the trachea and is connected with external pneumatic pump, the quantity of gas outlet (402) is the multiunit, and multiunit gas outlet (402) equidistance distributes the outer wall at tensile pipe (401), the inner wall sliding connection of tensile pipe (401) has piston (404), and cavity (403) are seted up to the inside of tensile pipe (401), be provided with the recess in the diapire of tensile pipe (401), multiunit top stretch piece (405) all set up in the recess, and multiunit top stretch piece (405) circular distribution in tensile pipe (401) diapire, multiunit top stretch piece (405) outer wall be the circular arc lateral wall, and multiunit top stretch piece (405) expansion diameter slightly is greater than the diameter of bottle embryo.

2. The stretching mechanism of a plastic bottle preform for a plastic bottle injection mold according to claim 1, wherein: the top of block (3) is provided with the mounting disc, and block (3) and mounting disc pass through the bearing and rotate to be connected, blowing mould (1) comprises two sets of mould bodies (101), and the one end of blowing mould (1) is provided with the rotation seat, two sets of mould bodies (101) are all rotated through pivot and rotation seat and are connected.

3. The stretching mechanism of a plastic bottle preform for a plastic bottle injection mold according to claim 1, wherein: one side of rack board (501) is arranged in the inner wall of stretching pipe (401) and is provided with a power gear (502), and power gear (502) is connected with rack board (501) through gear engagement, and power gear (502) is connected with the inner wall rotation of stretching pipe (401) through the bearing, the bottom of power gear (502) is connected with driven gear (503) through gear engagement, and the one end fixedly connected with initiative carousel (504) of driven gear (503), the outer wall connection of initiative carousel (504) has driving belt (505).

4. A stretching mechanism for a plastic bottle preform for a plastic bottle injection mold according to claim 3, wherein: the inside of driving belt (505) is located the below of driven gear (503) and installs driven carousel (506), and the one end and the drive gear (601) of driven carousel (506) pass through axle connector fixed connection, one side below of drive gear (601) is connected with rotation gear (602) through gear engagement, and rotation gear (602) and top stretch piece (405) and pass through fixed axle (604) fixed connection, torsional spring (603) are installed to the one end of rotation gear (602), and the inner wall fixed connection of torsional spring (603) and tensile pipe (401).

5. The stretching mechanism of a plastic bottle preform for a plastic bottle injection mold according to claim 1, wherein: the end face of the arc plate (701) is provided with an arc groove, the outer wall of the clamping block (3) is provided with a sliding block (702) matched with the inner wall of the arc groove, the inside of the clamping block (3) is provided with a clamping groove matched with the bottle embryo port, and the inner wall of the clamping groove is provided with a thread wall matched with the bottle embryo port thread.

6. The stretching mechanism of a plastic bottle preform for a plastic bottle injection mold according to claim 1, wherein: the auxiliary blanking mechanism (8) comprises a placing groove (801) which is arranged on the side wall of the die body (101), rubber hoses (802) are rotatably connected to the inside of the placing groove (801) through bearings, the number of the rubber hoses (802) is two, one group of the rubber hoses is provided with a regulating gear (803) at the bottom end of each rubber hose (802), the bottom end of each rubber hose (802) is fixedly connected with the top end of each regulating gear, the other group of the rubber hoses (802) is fixedly connected with a connecting shaft (805) at the bottom end of each rubber hose, and the bottom ends of the connecting shafts (805) are fixedly connected with the top ends of the regulating gears (803).

7. The stretching mechanism of plastic bottle preform for plastic bottle injection mold according to claim 6, wherein: one end of the adjusting gear (803) is provided with an arc rack (804) penetrating into the die body (101), the arc rack (804) is connected with the adjusting gear (803) through gear engagement, one end of the arc rack (804) is fixedly connected with the side wall of the die body (101), and the arc rack (804) is slidably connected with the inner wall of the die body (101).