CN118789757A

CN118789757A - Molding equipment and molding method for molded plastic preforms

Info

Publication number: CN118789757A
Application number: CN202411178663.2A
Authority: CN
Inventors: 彭宗海
Original assignee: Anhui Shunda Molding Technology Co Ltd
Current assignee: Anhui Shunda Molding Technology Co Ltd
Priority date: 2024-08-27
Filing date: 2024-08-27
Publication date: 2024-10-18

Abstract

The invention discloses a molding device and a molding method for molded plastic preforms, and relates to the technical field of plastic injection molding, including a frame; a feeding mechanism; a rotating shaft; and multiple groups of mold mechanisms, each of which is fixedly connected to the rotating shaft, each of which comprises a cross bar fixedly connected to the rotating shaft, a bottom mold being slidably connected to the cross bar, and a travel rod slidably connected to a travel groove, a mold frame being rotatably connected to the travel rod, and two opening and closing molds being slidably connected to the mold frame, and the two opening and closing molds being abutted and matched with each other; the multiple groups of mold mechanisms are driven to move synchronously by the rotating shaft, so that the injection molding efficiency can be improved, and at the same time, the two opening and closing molds are moved away from each other, so that the molded injection molded parts are prevented from sticking to the two opening and closing molds; by limiting the bottom mold and sliding the two opening and closing molds, a material discharge space is provided between the bottom mold and the two opening and closing molds, and then the bottom mold slides toward the position of the two opening and closing molds, and in the process of sliding, the injection molded parts are passively demolded from the bottom mold and fall from the material discharge space.

Description

Molding plastic prefabricated member molding equipment and molding method

Technical Field

The invention relates to the technical field of plastic injection molding, in particular to molding equipment and a molding method for molding plastic prefabricated parts.

Background

The plastic prefabricated member is formed by recovering and heating waste plastic to make the waste plastic become molten, conveying the molten waste plastic into an injection mold through a conveying mechanism, solidifying and forming the molten waste plastic through cooling, and separating a fixed mold and a movable mold of the mold, so that the solidified and formed plastic part is taken out from the mold.

The publication number is: CN118061449B, named: the utility model provides a high-efficient injection molding device of household electrical appliances plastic accessory, it includes the workstation, fixedly on the workstation be provided with the supporting seat, fixedly on the supporting seat be provided with the unloading case, it is provided with anti-blocking pipe to slide on the unloading case, anti-blocking pipe is last to be fixedly provided with the crane, it is provided with the pivot to rotate on the unloading case, fixedly in the pivot is provided with the revolving plate, be provided with the connecting rod between revolving plate and the crane, the both ends of connecting rod are connected with revolving plate and crane rotation respectively.

In the prior art including the above patent, when injection molding operation is performed, a hydraulic cylinder drives a movable mold to perform reciprocating linear motion, so that the movable mold can be in close fit with a fixed mold, and the mold opening and closing actions are completed; however, when injection molding is performed each time, injection molding of one plastic part can be completed, and the working efficiency of injection molding needs to be improved; meanwhile, at the time of demolding, the molded plastic part may adhere to the fixed mold or the movable mold, making the molded plastic part difficult to remove.

Disclosure of Invention

The invention aims to provide a molding device and a molding method for molding plastic prefabricated parts, which are used for solving the defects in the prior art.

In order to achieve the above object, the present invention provides the following technical solutions: a molding plastic preform forming apparatus comprising:

the machine frame is provided with a travel groove;

the feeding mechanism comprises a hopper fixedly connected to the frame, the hopper is communicated with a conveying pipe, and the conveying pipe is rotationally connected with a packing auger;

The rotating shaft is rotationally connected to the frame;

the die comprises a plurality of groups of die mechanisms, each die mechanism is fixedly connected onto a rotating shaft, each die mechanism comprises a cross rod fixedly connected onto the rotating shaft, a bottom die is connected onto the cross rod in a sliding manner, the die rack is rotationally connected onto the travel rod, two opening and closing dies are slidingly connected onto the die rack, the two opening and closing dies are mutually in butt fit, the two opening and closing dies are simultaneously in butt fit with the bottom die, an opening and closing plate is fixedly connected onto the travel rod, the opening and closing plate is in sliding butt joint with the two opening and closing dies, a first gear is fixedly connected onto the travel rod, a first rack and a second rack are fixedly connected onto the rack, and the first rack and the second rack are in meshing fit with the first gear;

in the rotating process of the rotating shaft, the rotating shaft sequentially has a first stroke, a second stroke, a third stroke and a fourth stroke:

in the first pass: the two opening and closing dies push the bottom die to slide on the cross bar along a first direction, so that the bottom die is communicated and matched with the mouth part of the conveying pipe;

In the second stroke: the two opening and closing dies and the bottom die synchronously slide on the cross bar along the second direction, and the two opening and closing dies are mutually far away and reset, so that the injection molded plastic piece is separated from the two opening and closing dies;

In the third stroke: the bottom die keeps static, and the two open-close dies continue to slide on the cross bar along the second direction, so that the two open-close dies are far away from the bottom die;

In the fourth stroke: the two opening and closing dies are kept static, the bottom die continues to slide on the cross bar along the second direction, and in the sliding process, the plastic piece on the bottom die is demolded.

Further, the travel groove is formed by communicating a round groove, a communicating groove and a separating groove.

Further in, still including setting up the stop gear on the horizontal pole, stop gear is including rotating the driving lever of connection on the horizontal pole, and one of them compound die butt cooperation of driving lever's one end, the other end rotation is connected with the connecting rod, and connecting rod transverse sliding connection is on the horizontal pole, rotates on the connecting rod and is connected with the slider, and slider transverse sliding connection is on the horizontal pole, and vertical sliding connection has the stopper on the horizontal pole, stopper and slider sliding butt are provided with first spring between stopper and the horizontal pole, stopper and die block butt cooperation are provided with the second spring between die block and the horizontal pole.

Further, a first abutting rod is fixedly connected to the limiting block, a lifting groove is formed in the sliding block, and the first abutting rod is slidably connected in the lifting groove.

Further, the limiting block is provided with an abutting inclined plane and a limiting plane, the bottom die is in abutting fit with the abutting inclined plane, the bottom die is provided with a positioning plane, and the positioning plane is in abutting fit with the limiting plane.

Further, the material cutting and demolding mechanism comprises two scissors which are transversely connected onto the bottom mold in a sliding mode, second abutting rods are fixedly connected onto the two scissors, a turntable is connected to the bottom mold in a rotating mode, two cutting grooves are formed in the turntable, the two second abutting rods are in sliding abutting joint with the two cutting grooves in a one-to-one mode, a sleeve is fixedly connected onto the turntable, two ejection grooves are formed in the sleeve, a communicating material pipe is connected onto the bottom mold in a sliding mode and matched with the opening portion of the conveying pipe in a communicating mode, two third abutting rods are fixedly connected onto the communicating material pipe, and the two third abutting rods are in sliding abutting joint with the two ejection grooves in a one-to-one mode.

Further, the shearing trough is formed by communicating a near section, a far section and a coaxial arc trough.

Further, the ejector groove is formed by communicating a holding section and an ejector section.

Further in, still include link gear, it includes the bevel gear dish of fixed connection on the carousel, rotate on the die block and be connected with the bevel gear, bevel gear and bevel gear dish meshing, fixedly connected with dwang on the bevel gear, fixedly connected with pawl on the dwang, rotate on the die block and be connected with the ratchet, pawl and ratchet joint cooperation, fixedly connected with second gear on the ratchet, fixedly connected with third rack on the horizontal pole, third rack and second gear meshing cooperation, set up the logical groove that supplies the third rack to pass on the die block.

A molding method employing the molding plastic preform molding apparatus as described above, comprising the steps of:

step one: adding waste plastics into the hopper, and heating the conveying pipe to enable the waste plastics to be heated to be in a molten state;

Step two: the rotating shaft is driven to rotate along a first direction, so that the rotating shaft drives each group of die mechanisms to synchronously move, and a travel rod in one group of die mechanisms is driven to slide in a communication groove of the travel groove, so that the bottom die is communicated with the mouth of the conveying pipe;

Step three: driving the auger to rotate, and enabling the waste plastics in a molten state to flow out from the mouth of the conveying pipe through rotation and flow into an injection molding space formed between the bottom die and the two opening and closing dies through the communicating pipe;

Step four: the method comprises the steps of cooling waste plastics in a molten state in an injection molding space, continuously driving a rotating shaft to rotate along a first direction after cooling is finished, enabling a travel rod to slide in a separation groove, enabling a bottom die to be far away from a conveying pipe, enabling the bottom die and two opening and closing dies to synchronously slide on a cross rod, enabling the two opening and closing dies to be mutually separated firstly through meshing and matching of a first gear and a second gear respectively in the sliding process, resetting the two opening and closing dies, enabling an injection molding piece to be separated from the two opening and closing dies firstly, enabling the bottom die to be limited by a limiting plane of a limiting block in an abutting mode in the sliding process, and enabling the two opening and closing dies to continuously slide on the cross rod;

Step five: as the rotating shaft continues to rotate, the two opening and closing dies are abutted with the deflector rod in the sliding process, the deflector rod is driven to rotate, the deflector rod drives the connecting rod and the sliding block to transversely move, the sliding block is matched with the sliding abutment of the limiting block, the limiting block vertically moves upwards, the limiting block is separated from the bottom die, and the bottom die slides to the position where the two opening and closing dies are located under the action of the elasticity of the second spring;

Step six: in the sliding process of the bottom die to the position where the two open and close dies are located, the second gear is meshed with the third gear to drive the ratchet wheel, the pawl, the bevel gear disk, the rotary table and the sleeve to rotate, the rotary table rotates to drive the two scissors to approach and separate from each other, the two scissors cut the leftover materials at the pouring gate, the sleeve rotates to drive the communicating material pipe to push out to one end of the rotary table, and the injection molding piece cut by the leftover materials is separated from the bottom die from top to bottom, so that the demoulding action is completed.

In the technical scheme, the invention provides molding plastic prefabricated member forming equipment:

1. the rotating shaft drives the multiple groups of die mechanisms to synchronously move, so that the injection molding efficiency can be improved, and meanwhile, the two open and close dies are mutually far away, so that adhesion between a molded injection molding piece and the two open and close dies is avoided; through limiting the bottom die, the two open and close dies slide, a blanking space is formed between the bottom die and the two open and close dies, the bottom die slides to the two open and close dies, and the injection molding part is passively demoulded from the bottom die in the sliding process and falls from the blanking space.

2. By arranging the shearing and demolding mechanism, the turntable drives the two scissors to approach each other through the rotation of the turntable and the sleeve, so that the gate leftover materials are cut, and the subsequent cutting operation of the edge leftover materials is avoided; the sleeve drives the communicating pipe to eject to the outside of the bottom die, so that the communicating pipe supplements plastic materials in a molten state and simultaneously has the functions of demolding and discharging.

3. Through the cooperation of the linkage mechanism and the limiting mechanism, the second gear, the third rack, the ratchet and the pawl are matched, so that power is provided for the linkage mechanism in the process that the bottom die slides to the two die opening and closing positions, and the power is transmitted to the shearing and demolding mechanism through the linkage mechanism; meanwhile, when the bottom die approaches to the position of the conveying pipe, the linkage mechanism and the shearing demoulding mechanism do not work due to the unidirectional transmission function of the linkage mechanism.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments described in the present application, and other drawings may be obtained according to these drawings for a person having ordinary skill in the art.

FIG. 1 is a schematic diagram of an overall structure according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a feeding mechanism according to an embodiment of the present invention;

fig. 3 is a schematic top view of a rack according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of a cross-bar according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a mold mechanism according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a limiting mechanism according to an embodiment of the present invention;

FIG. 7 is a schematic view of a bottom mold according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a cross-sectional structure of a bottom mold according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a material shearing and demolding mechanism provided by an embodiment of the invention;

FIG. 10 is a schematic diagram of a turntable according to an embodiment of the present invention;

FIG. 11 is a schematic view of a sleeve structure according to an embodiment of the present invention;

fig. 12 is a schematic diagram of a partial enlarged structure at a provided by an embodiment of the present invention.

Reference numerals illustrate:

1. A frame; 11. a circular groove; 12. a communication groove; 13. a disengagement groove; 2. a feeding mechanism; 21. a hopper; 22. a delivery tube; 23. an auger; 3. a rotating shaft; 4. a mold mechanism; 41. a cross bar; 42. a bottom die; 421. a through groove; 422. positioning a plane; 43. a travel bar; 44. a mould frame; 45. opening and closing the die; 46. an opening plate; 47. a first gear; 48. a first rack; 49. a second rack; 5. a limiting mechanism; 52. a connecting rod; 53. a slide block; 531. a lifting groove; 54. a first abutting rod; 55. a limiting block; 551. abutting the inclined plane; 552. a limit plane; 56. a first spring; 57. a second spring; 6. a shearing and demoulding mechanism; 61. a pair of scissors; 62. a second abutting rod; 63. a turntable; 631. a proximal segment; 632. a distance segment; 633. a coaxial arc slot; 64. a sleeve; 641. a holding section; 642. an ejection section; 65. a communicating pipe; 651. a third abutment rod; 7. a linkage mechanism; 71. bevel gear disk; 72. bevel gears; 73. a rotating lever; 74. a pawl; 75. a ratchet wheel; 76. a second gear; 77. and a third rack.

Detailed Description

In order to make the technical scheme of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings.

Referring to fig. 1-12, an apparatus for molding plastic preforms according to an embodiment of the invention includes: the device comprises a frame 1, wherein a travel groove is formed in the frame 1; the feeding mechanism 2 comprises a hopper 21 fixedly connected to the frame 1, the hopper 21 is communicated with a conveying pipe 22, and the conveying pipe 22 is rotatably connected with a packing auger 23.

A rotating shaft 3 rotatably connected to the frame 1; the frame 1 is fixedly connected with a driving source for driving the rotating shaft 3 to intermittently rotate, the driving source is a motor, and the output end of the motor is coaxially and fixedly connected with the rotating shaft 3.

In the embodiments of the present invention: each die mechanism 4 is fixedly connected to the rotating shaft 3, each die mechanism 4 comprises a cross rod 41 fixedly connected to the rotating shaft 3, a bottom die 42 is connected to the cross rod 41 in a sliding mode, the die comprises a travel rod 43 which is connected to the travel groove in a sliding mode, a die frame 44 is connected to the travel rod 43 in a rotating mode, two opening and closing dies 45 are connected to the die frame 44 in a sliding mode, the two opening and closing dies 45 are in mutual abutting fit, the two opening and closing dies 45 are simultaneously in abutting fit with the bottom die 42, an opening and closing plate 46 is fixedly connected to the travel rod 43, the opening and closing plate 46 is in sliding abutting fit with the two opening and closing dies 45, a first gear 47 is fixedly connected to the travel rod 43, a first rack 48 and a second rack 49 are fixedly connected to the machine frame 1, and the first rack 48 and the second rack 49 are in meshing fit with the first gear 47.

Specifically, the bottoms of the two opening and closing dies 45 are fixedly connected with vertical rods, the die carrier 44 is symmetrically provided with two straight grooves, the two vertical rods are respectively and correspondingly slidably connected in the two straight grooves one by one, the opening and closing plate 46 is fixedly connected with two obliquely arranged guide frames, and the two guide frames are respectively and correspondingly slidably abutted with the two vertical rods one by one; when the opening plates 46 are rotated, the two opening plates 46 can be driven to be far away from each other through the common cooperation of the guide frame, the straight groove and the vertical rods, so that the injection molded plastic piece is separated from the two opening plates 46 through the mutual separation of the two opening plates 46.

In the process of rotating the rotating shaft 3, the rotating shaft sequentially has a first stroke, a second stroke, a third stroke and a fourth stroke:

in the first pass: the two opening and closing dies 45 push the bottom die 42 to slide on the cross bar 41 along the first direction, so that the bottom die 42 is matched with the mouth part of the conveying pipe 22 in a communicating way;

In the second stroke: the two opening and closing dies 45 and the bottom die 42 synchronously slide on the cross bar 41 along the second direction, and the two opening and closing dies 45 are mutually far away and reset, so that the injection molded plastic part is separated from the two opening and closing dies 45;

In the third stroke: the bottom die 42 remains stationary while the two mold opening and closing dies 45 continue to slide on the cross bar 41 in the second direction, causing the two mold opening and closing dies 45 to move away from the bottom die 42;

In the fourth stroke: the two opening and closing dies 45 remain stationary, and the bottom die 42 continues to slide on the cross bar 41 in the second direction, and during the sliding process, the plastic part on the bottom die 42 is demolded.

The travel groove is composed of a round groove 11, a communicating groove 12 and a separating groove 13.

In the embodiments of the present invention: the die comprises a cross bar 41, a bottom die 42, a limiting mechanism 5, a die opening and closing mechanism 45, a die opening and closing mechanism 5 and a die closing mechanism, wherein the cross bar 41 is arranged on the cross bar; the limiting mechanism 5 comprises a deflector rod 51 rotatably connected to the cross rod 41, one end of the deflector rod 51 is in abutting fit with one of the opening and closing dies 45, the other end of the deflector rod 51 is rotatably connected with a connecting rod 52, and the cross rod 41 is provided with a rotating groove for the connecting rod 52 to rotate; the connecting rod 52 is transversely and slidably connected to the cross rod 41, and a transverse groove for the connecting rod 52 to transversely slide is formed in the cross rod 41; the connecting rod 52 is rotationally connected with a sliding block 53, the sliding block 53 is transversely and slidably connected to the cross rod 41, the cross rod 41 is vertically and slidably connected with a limiting block 55, the limiting block 55 is in sliding contact with the sliding block 53, a first spring 56 is arranged between the limiting block 55 and the cross rod 41, the limiting block 55 is in contact with the bottom die 42, and a second spring 57 is arranged between the bottom die 42 and the cross rod 41.

Specifically, the first abutting rod 54 is fixedly connected to the limiting block 55, the sliding block 53 is provided with a lifting groove 531, and the first abutting rod 54 is slidably connected in the lifting groove 531.

Specifically, the stopper 55 has an abutment inclined surface 551 and a limiting plane 552, the bottom die 42 is in abutment fit with the abutment inclined surface 551, the bottom die 42 has a positioning plane 422, and the positioning plane 422 is in abutment fit with the limiting plane 552.

It should be noted that: as shown in fig. 5, the top parts of the two mold opening and closing modules 45 are provided with a notch, and the stopper 55 can be prevented from abutting the mold opening and closing modules 45 by the arrangement of the notch, thereby generating an interference effect.

In the embodiments of the present invention: the plastic injection molding machine also comprises a material shearing and demolding mechanism 6, wherein the material shearing and demolding mechanism 6 has two functions, namely, the mouth part of the conveying pipe 22 is communicated with the injection molding space through the communicating pipe 65, so that after molten plastic is cooled, the molten plastic in the communicating pipe 65 is cooled and solidified, and is integrated with an injection molded plastic part, and the leftover materials (called as a gate in the prior art) in the communicating pipe 65 can be subjected to material shearing and demolding; secondly, the cut injection molding piece can be ejected outwards through the communicating pipe 65, and the cut injection molding piece can be ejected from the bottom die 42 and falls from a blanking space between the bottom die 42 and the two opening and closing dies 45, so that demolding and blanking are completed.

Specifically, the material cutting demoulding mechanism 6 comprises two scissors 61 which are transversely and slidably connected to the bottom die 42, second supporting rods 62 are fixedly connected to the two scissors 61, a rotary table 63 is rotationally connected to the bottom die 42, two cutting grooves are formed in the rotary table 63, the two second supporting rods 62 are respectively in sliding butt joint with the two cutting grooves in a one-to-one correspondence manner, a sleeve 64 is fixedly connected to the rotary table 63, two ejecting grooves are formed in the sleeve 64, a communicating pipe 65 is slidably connected to the bottom die 42, the communicating pipe 65 is in communication fit with the opening of the conveying pipe 22, two third supporting rods 651 are fixedly connected to the communicating pipe 65, and the two third supporting rods 651 are respectively in sliding butt joint with the two ejecting grooves in a one-to-one correspondence manner.

Specifically, the shearing groove is formed by communicating a near section 631, a far section 632 and a coaxial arc groove 633; more specifically, the coaxial arc groove 633 is formed coaxially with the turntable 63; as shown in fig. 10, when the approaching section 631 is matched with the second abutting rod 62, the two scissors 61 are driven to approach each other by the clockwise rotation of the turntable 63, and the cutting action is realized on the leftover; when the far section 632 is matched with the second abutting rod 62, the two scissors 61 after finishing the cutting action are driven to reset; when the coaxial arc groove 633 is engaged with the second abutting rod 62, the two scissors 61 are driven to keep stationary, and are always in an initial state, namely: the two scissors 61 are away from each other.

Specifically, the ejector groove is formed by communicating a holding section 641 and an ejector section 642; as shown in fig. 11, during rotation of sleeve 64 along its axis, when holding segment 641 cooperates with third abutment bar 651, communicating tube 65 can be urged to remain stationary; when the ejection section 642 is engaged with the third abutting rod 651, the communicating tube 65 is driven to slide on the bottom die 42, so that the end of the communicating tube 65 extends and ejects to the outside of the bottom die 42, and the end of the communicating tube 65 ejects the molded plastic part, thereby completing demolding.

Preferably, the device also comprises a linkage mechanism 7 which passively provides power for the shearing and demolding mechanism 6 in the process that the bottom die 42 is far away from the conveying pipe 22; the rotary table comprises a bevel gear disc 71 fixedly connected to a rotary table 63, a bevel gear 72 is rotatably connected to a bottom die 42, the bevel gear 72 is meshed with the bevel gear disc 71, a rotary rod 73 is fixedly connected to the bevel gear 72, a pawl 74 is fixedly connected to the rotary rod 73, a ratchet 75 is rotatably connected to the bottom die 42, the pawl 74 is matched with the ratchet 75 in a clamping manner, a second gear 76 is fixedly connected to the ratchet 75, a third rack 77 is fixedly connected to a cross rod 41, the third rack 77 is meshed with the second gear 76, and a through groove 421 for the third rack 77 to pass through is formed in the bottom die 42.

Through the unidirectional transmission of the ratchet wheel 75 and the pawl 74 and the meshing cooperation of the third rack 77 and the second gear 76, when the bottom die 42 approaches to the position of the conveying pipe 22, the ratchet wheel 75 does not drive the pawl 74 to rotate synchronously, namely: the material shearing and demolding mechanism 6 cannot be driven to work through the linkage mechanism 7; when the bottom die 42 is far away from the conveying pipe 22, the ratchet 75, the pawl 74, the bevel gear 72, the bevel gear disc 71, the rotary table 63 and the sleeve 64 are driven to rotate by the engagement of the third rack 77 and the second gear 76, so that the two scissors 61 cut the scraps at the pouring gate, and the connecting pipe 65 performs ejection to the rotary table 63, thereby completing demoulding operation on the injection molding part.

It is worth mentioning that: a torsion spring is arranged between the rotating rod 73 and the bottom die 42, and the torsion spring has the following functions: after the second gear 76 and the third rack 77 are disengaged (namely, after finishing cutting and demoulding actions), the linkage mechanism 7 is driven to rotate and reset by the elasticity of the torsion spring.

step one: waste plastics are added into the hopper 21, and the conveying pipe 22 is heated to make the waste plastics become a molten state under the heat;

Step two: the rotating shaft 3 is driven to rotate along the first direction, so that the rotating shaft 3 drives the die mechanisms 4 of each group to synchronously move, and drives the travel rod 43 in one die mechanism 4 to slide in the communicating groove 12 of the travel groove, thereby communicating the bottom die 42 with the mouth of the conveying pipe 22;

Step three: the auger 23 is driven to rotate, and the auger 23 rotates to flow out molten waste plastics from the mouth of the conveying pipe 22 and flow into an injection molding space formed between the bottom die 42 and the two opening and closing dies 45 through the communicating pipe 65;

Step four: after cooling, the rotating shaft 3 is continuously driven to rotate along a first direction, so that the travel rod 43 slides in the separation groove 13, the bottom die 42 is far away from the conveying pipe 22, the bottom die 42 and the two opening and closing dies 45 synchronously slide on the cross rod 41, in the sliding process, the two opening and closing dies 45 are mutually separated firstly and then reset through the meshing fit of the first gear 47 with the first rack 48 and the second rack 49 respectively, the injection molding piece is separated from the two opening and closing dies 45 firstly, then the bottom die 42 is abutted and limited by the limiting plane 552 of the limiting block 55 in the sliding process, and the two opening and closing dies 45 continuously slide on the cross rod 41;

Step five: as the rotating shaft 3 continues to rotate, the two opening and closing dies 45 are abutted with the deflector rod 51 in the sliding process, the deflector rod 51 is driven to rotate, the deflector rod 51 drives the connecting rod 52 and the sliding block 53 to transversely move, the sliding block 53 is matched with the sliding abutment of the limiting block 55, the limiting block 55 vertically moves upwards, the limiting block 55 is separated from abutment with the bottom die 42, and the bottom die 42 slides to the position where the two opening and closing dies 45 are located under the action of the elasticity of the second spring 57;

Step six: in the process that the bottom die 42 slides to the position where the two opening and closing dies 45 are located, the second gear 76 is meshed and matched with the third rack 77 to drive the ratchet wheel 75, the pawl 74, the bevel gear 72, the bevel gear disc 71, the rotary disc 63 and the sleeve 64 to rotate, the rotation of the rotary disc 63 drives the two scissors 61 to be close to and far away from each other, the two scissors 61 cut the leftover materials at the pouring gate, the rotation of the sleeve 64 drives the communicating pipe 65 to push out to one end of the rotary disc 63, and the injection molding piece cut by the leftover materials is separated from the bottom die 42 from top to bottom, so that the demoulding action is completed.

While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that modifications may be made to the described embodiments in various different ways without departing from the spirit and scope of the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive of the scope of the invention, which is defined by the appended claims.

Claims

1. A molding plastic preform forming device, characterized in that it comprises:

A frame (1), wherein a travel slot is provided on the frame (1);

The feeding mechanism (2) comprises a hopper (21) fixedly connected to the frame (1), the hopper (21) is connected to a conveying pipe (22), and an auger (23) is rotatably connected inside the conveying pipe (22);

A rotating shaft (3) rotatably connected to the frame (1);

A plurality of mold mechanisms (4), each mold mechanism (4) is fixedly connected to the rotating shaft (3), each mold mechanism (4) comprises a cross bar (41) fixedly connected to the rotating shaft (3), a bottom mold (42) is slidably connected to the cross bar (41), and a travel rod (43) is slidably connected to the travel groove, a mold frame (44) is rotatably connected to the travel rod (43), and two opening and closing molds (45) are slidably connected to the mold frame (44), and the two opening and closing molds (45) are mutually rotatably connected. The two opening and closing molds (45) are in abutment with each other, and the two opening and closing molds (45) are in abutment with the bottom mold (42) at the same time. The stroke rod (43) is fixedly connected with an opening and closing plate (46), and the opening and closing plate (46) is in sliding abutment with the two opening and closing molds (45). The stroke rod (43) is fixedly connected with a first gear (47), and the frame (1) is fixedly connected with a first rack (48) and a second rack (49), and the first rack (48) and the second rack (49) are both in meshing cooperation with the first gear (47);

During the rotation of the rotating shaft (3), there are a first stroke, a second stroke, a third stroke and a fourth stroke in sequence:

In the first stroke: the two opening and closing molds (45) push the bottom mold (42) to slide on the cross bar (41) along the first direction, so that the bottom mold (42) is connected and matched with the mouth of the conveying pipe (22);

In the second stroke: the two opening and closing molds (45) and the bottom mold (42) slide synchronously on the crossbar (41) along the second direction, and the two opening and closing molds (45) move away from each other and reset, so that the injection-molded plastic part is separated from the two opening and closing molds (45);

In the third stroke: the bottom mold (42) remains stationary, while the two-opening and closing molds (45) continue to slide on the cross bar (41) along the second direction, so that the two-opening and closing molds (45) are away from the bottom mold (42);

In the fourth stroke: the two opening and closing molds (45) remain stationary, and the bottom mold (42) continues to slide on the cross bar (41) along the second direction, and during the sliding process, the plastic parts on the bottom mold (42) are demoulded.

2. A molding plastic preform forming device according to claim 1, characterized in that the travel groove is composed of a circular groove (11), a connecting groove (12) and a separation groove (13) connected to each other.

3. A molding plastic preform forming device according to claim 1, characterized in that it also includes a limiting mechanism (5) arranged on the cross bar (41), the limiting mechanism (5) including a shifting rod (51) rotatably connected to the cross bar (41), one end of the shifting rod (51) abuts and cooperates with one of the opening and closing molds (45), and the other end is rotatably connected to a connecting rod (52), the connecting rod (52) is laterally slidably connected to the cross bar (41), a sliding block (53) is rotatably connected to the connecting rod (52), the sliding block (53) is laterally slidably connected to the cross bar (41), a limiting block (55) is vertically slidably connected to the cross bar (41), the limiting block (55) is slidably abutted against the sliding block (53), a first spring (56) is arranged between the limiting block (55) and the cross bar (41), the limiting block (55) abuts and cooperates with the bottom mold (42), and a second spring (57) is arranged between the bottom mold (42) and the cross bar (41).

4. A molding plastic preform forming device according to claim 3, characterized in that a first abutment rod (54) is fixedly connected to the limit block (55), a lifting groove (531) is provided on the slider (53), and the first abutment rod (54) is slidably connected in the lifting groove (531).

5. A molding plastic preform forming device according to claim 3, characterized in that the limit block (55) has an abutment slope (551) and a limit plane (552), the bottom mold (42) abuts against the abutment slope (551), the bottom mold (42) has a positioning plane (422), and the positioning plane (422) abuts against the limit plane (552).

6. A molding plastic preform forming device according to claim 1, characterized in that it also includes a shearing and demolding mechanism (6), which includes two scissors (61) laterally slidably connected to the bottom mold (42), and the two scissors (61) are fixedly connected to a second abutment rod (62), a turntable (63) is rotatably connected inside the bottom mold (42), and the turntable (63) is provided with two shearing grooves, and the two second abutment rods (62) are respectively and one by one correspondingly slidably abutted with the two shearing grooves, a sleeve (64) is fixedly connected to the turntable (63), and two ejecting grooves are provided on the sleeve (64), and a connecting material pipe (65) is slidably connected to the bottom mold (42), and the connecting material pipe (65) is connected and cooperated with the mouth of the conveying pipe (22), and two third abutment rods (651) are fixedly connected to the connecting material pipe (65), and the two third abutment rods (651) are respectively and one by one correspondingly slidably abutted with the two ejecting grooves.

7. A molding plastic preform forming device according to claim 6, characterized in that the shearing groove is composed of a close section (631), a distant section (632) and a coaxial arc groove (633).

8. A molding plastic preform forming device according to claim 6, characterized in that the ejection chute is composed of a holding section (641) and an ejection section (642) connected to each other.

9. A molding plastic preform forming device according to claim 6, characterized in that it also includes a linkage mechanism (7), which includes a bevel gear plate (71) fixedly connected to the turntable (63), a bevel gear (72) rotatably connected to the bottom mold (42), the bevel gear (72) meshes with the bevel gear plate (71), a rotating rod (73) fixedly connected to the bevel gear (72), a pawl (74) fixedly connected to the rotating rod (73), a ratchet (75) rotatably connected to the bottom mold (42), the pawl (74) and the ratchet (75) are snap-fitted, a second gear (76) is fixedly connected to the ratchet (75), a third rack (77) is fixedly connected to the cross bar (41), the third rack (77) meshes with the second gear (76), and a through groove (421) for the third rack (77) to pass through is opened on the bottom mold (42).

10. A molding method, using the molding plastic preform molding device according to claims 1 to 9, characterized in that it comprises the following steps:

Step 1: Add waste plastics into the hopper (21) and heat the conveying pipe (22) to heat the waste plastics into a molten state;

Step 2: driving the rotating shaft (3) to rotate in a first direction, so that the rotating shaft (3) drives each group of mold mechanisms (4) to move synchronously, and drives the travel rod (43) in one group of mold mechanisms (4) to slide in the connecting groove (12) of the travel groove, so that the bottom mold (42) is connected with the mouth of the conveying pipe (22);

Step 3: driving the auger (23) to rotate, and the auger (23) rotates to make the molten waste plastic flow out from the mouth of the conveying pipe (22), and flow into the injection molding space formed between the bottom mold (42) and the two opening and closing molds (45) through the connecting material pipe (65);

Step 4: Cooling the molten waste plastic in the injection molding space. After cooling, continue to drive the rotating shaft (3) to rotate in the first direction, so that the stroke rod (43) slides in the disengagement groove (13), so that the bottom mold (42) moves away from the conveying pipe (22), and the bottom mold (42) and the two opening and closing molds (45) slide synchronously on the cross bar (41). During the sliding process, the first gear (47) is respectively engaged with the first rack (48) and the second rack (49), so that the two opening and closing molds (45) are first moved away from each other and then reset, so that the injection molded part is first separated from the two opening and closing molds (45). Subsequently, the bottom mold (42) is abutted and limited by the limiting plane (552) of the limiting block (55) during the sliding process, and the two opening and closing molds (45) continue to slide on the cross bar (41);

Step 5: As the rotating shaft (3) continues to rotate, the two-opening and closing molds (45) will abut against the lever (51) during the sliding process, driving the lever (51) to rotate, and the lever (51) drives the connecting rod (52) and the slider (53) to move horizontally. Through the sliding abutment cooperation between the slider (53) and the limit block (55), the limit block (55) moves vertically upward, so that the limit block (55) and the bottom mold (42) are separated from the abutment. Under the elastic force of the second spring (57), the bottom mold (42) slides to the position where the two-opening and closing molds (45) are located;

Step 6: During the process of the bottom mold (42) sliding toward the position where the two-opening and closing molds (45) are located, the second gear (76) and the third rack (77) are meshed and cooperated to drive the ratchet (75), the pawl (74), the bevel gear (72), the bevel gear plate (71), the turntable (63), and the sleeve (64) to rotate. The rotation of the turntable (63) drives the two scissors (61) to approach and move away from each other, so that the two scissors (61) cut the scraps at the gate. The rotation of the sleeve (64) drives the connecting material pipe (65) to be pushed out toward one end of the turntable (63), and the injection molded part with the scraps cut off is pushed down and separated from the bottom mold (42), thereby completing the demoulding action.