CN110466110B

CN110466110B - Production process for safety helmet

Info

Publication number: CN110466110B
Application number: CN201910815245.2A
Authority: CN
Inventors: 代忠
Original assignee: Chongqing Yong An Security And Protection Technology Co ltd
Current assignee: Chongqing Yong An Security And Protection Technology Co ltd
Priority date: 2019-08-30
Filing date: 2019-08-30
Publication date: 2021-04-06
Anticipated expiration: 2039-08-30
Also published as: CN110466110A

Abstract

The invention relates to the technical field of safety helmets; discloses a production process for safety helmets, which comprises the following steps: (1) selecting a polyformaldehyde raw material; (2) mixing polyformaldehyde raw materials; (3) selecting injection molding raw materials; (4) mixing injection molding raw materials; (5) and (5) injection molding. This scheme has mainly solved present raw materials of moulding plastics can cause the loss because of the collision at the in-process of transportation, and then influences the injection moulding in later stage, leads to the problem that the production efficiency of safety helmet is low.

Description

Production process for safety helmet

Technical Field

The invention relates to the technical field of safety helmets.

Background

The safety helmet is a hat which can protect the head of a person from being hurt by falling objects and other specific factors. The safety helmet consists of a helmet shell, a helmet liner, a chin strap, accessories and the like.

At present, the safety helmet is mainly manufactured by injection molding and is finished by later-stage finish machining; the injection molding raw materials need to be prepared by stirring and mixing a plurality of raw materials, but the existing stirrer has poor stirring and mixing effects on the plurality of raw materials, and even the existing stirrer can form piles or balls, which directly influences the later injection molding effect; in addition, the injection molding raw material is obtained by stirring through a stirrer, needs to be transported into an injection machine through a storage tool, is heated and melted through the injection machine, and is injected into an injection mold under the pushing of a screw or a piston of the injection machine; above-mentioned operation raw materials of moulding plastics can cause the loss because of the collision at the in-process of transportation, and then influences the injection moulding in later stage, leads to the production efficiency of safety helmet low.

Disclosure of Invention

The invention aims to provide a production process for safety helmets, and aims to solve the problem that the production efficiency of the safety helmets is low due to the fact that the injection molding raw materials are lost due to collision in the transportation process, and the later injection molding is affected.

In order to achieve the above object, the basic scheme of the invention is as follows: a production process for safety helmets comprises the following steps:

(1) selecting a polyformaldehyde raw material: selecting the following raw materials in parts by weight: 60-80 parts of trioxymethylene, 15-30 parts of dioxolane and 10-20 parts of boron trifluoride diethyl etherate;

(2) mixing polyformaldehyde raw materials: uniformly mixing the polyformaldehyde raw materials in the step (1), and reacting at the temperature of 65-70 ℃ for 2-3 hours to obtain polyformaldehyde;

(3) selecting injection molding raw materials: selecting the following raw materials in parts by weight: 70-90 parts of polyformaldehyde, 10-20 parts of nano mica sheet powder, 1-3 parts of nano magnesium aluminum oxide and 1-5 parts of zinc oxide;

(4) mixing injection molding raw materials: the injection molding device comprises a base, wherein a stirring mechanism, an injection machine and an injection molding mechanism which are communicated with each other are arranged on the base, and the injection molding raw material in the step (3) is put into the stirring mechanism and uniformly mixed to obtain a raw material body;

(5) injection molding: and (4) injecting the raw material body obtained in the step (4) into an injection molding mechanism through an injection machine for injection molding to obtain the safety helmet injection molding part.

The advantages of the basic scheme are: according to the scheme, the four injection molding raw materials are uniformly stirred and mixed through the stirring mechanism to obtain a raw material body; introducing the raw material body into an injection machine, heating and melting the raw material body by the injection machine to be in a flowing state, and injecting the raw material body into an injection molding mechanism to finally obtain a safety helmet injection molding piece; compared with the existing production mode, the process of transporting the existing injection molding raw materials to the injection molding machine is reduced, the loss of the injection molding raw materials is avoided, the injection molding is further ensured, and the production efficiency of the safety helmet is improved.

Further, the stirring mechanism comprises a box body, the top of the box body is provided with a plurality of feeding pipes, and the bottom of the box body is provided with a discharging pipe; the top of the discharge pipe is provided with a screen, the middle of the discharge pipe is provided with a valve, and the bottom of the discharge pipe is communicated with an injection machine; a first-stage mixing unit and a second-stage mixing unit for mixing injection molding raw materials are arranged in the box body.

Through the setting, four kinds of raw materials of moulding plastics get into the box in through the inlet pipe, mix the processing through one-level mixing unit and second grade mixing unit to the raw materials of moulding plastics, and then have avoided the raw materials of moulding plastics to appear piling form or globular condition.

Further, the primary mixing unit comprises a motor and a sliding plate, the motor is fixedly connected to the outer wall of the box body, an output shaft of the motor is connected with a rotating shaft, and a cam is arranged on the rotating shaft; the sliding plate is connected to the side wall of the box body in a sliding mode, and a first spring is arranged between the sliding plate and the box body; a mixing barrel for collecting injection molding raw materials is arranged on the sliding plate and is positioned in the box body; a discharge port is formed in the bottom of the mixing barrel, and a through hole communicated with the discharge port is formed in the sliding plate; one end of the sliding plate, which is far away from the mixing barrel, is abutted against the cam.

Through the arrangement, the four injection molding raw materials fall into the mixing barrel; the output shaft of motor drives the pivot and rotates, and the pivot drives the cam and rotates, and the first spring of bellying intermittent type extrusion slide cooperation through the cam can drive the slide and be reciprocating motion along the horizontal direction, and then drives mixing drum on the slide and be reciprocating motion along the horizontal direction for four kinds of raw materials of moulding plastics realize preliminary mixing in the mixing drum, accomplish four kinds of raw materials of moulding plastics of preliminary mixing and remove to the bottom direction of box through discharge gate, through-hole.

Furthermore, a rack is connected to the side wall of the box body in a sliding manner, and a second spring is arranged between the rack and the box body; a plurality of feed inlets are formed in the rack, and the feed inlets and the feed pipes are arranged in a staggered manner; the rack is positioned above the sliding plate, and the bottom of the rack is abutted against the mixing barrel; and a sector gear meshed with the rack is arranged on the rotating shaft.

Through the setting, the output shaft of motor drives the pivot and rotates, and the pivot drives fan gear and rotates, and intermittent type meshing cooperation second spring through fan gear and rack can drive the rack and be reciprocating motion along the horizontal direction, and when the rack left removal, feed inlet on the rack communicates with each other with the inlet pipe for four kinds of raw materials of moulding plastics drop to the blending hopper in through the feed inlet, can four kinds of raw materials of moulding plastics of quantitative control get into the blending hopper and mix with this, strengthen the mixing effect.

Further, the secondary mixing unit comprises a linkage shaft and a driven bevel gear fixedly connected to the linkage shaft, and a stirring arm is arranged on the linkage shaft and is positioned in the box body; the linkage shaft is rotatably connected to the side wall of the box body and is positioned below the sliding plate; and a driving bevel gear meshed with the driven bevel gear is arranged on the rotating shaft.

Through the arrangement, the output shaft of the motor drives the rotating shaft to rotate, the rotating shaft drives the driving bevel gear to rotate, and the driven bevel gear is used for driving the linkage shaft to rotate through the meshing of the driving bevel gear and the driven bevel gear; the universal driving shaft drives the stirring arm to stir and mix the four injection molding raw materials at the bottom of the box body again, and finally a raw material body is obtained; in raw materials body collects the discharging tube through the screen cloth, can avoid piling form or globular raw materials body to get into the discharging tube through the screen cloth, can break up the processing through the rabbling arm to piling form or globular raw materials body.

Further, the injection molding mechanism comprises an upper die and a lower die, and the upper die is detachably connected with the lower die; an upper cavity is arranged at the bottom of the upper die, a lower cavity is arranged at the top of the lower die, and the upper cavity and the lower cavity form a safety cap cavity; the middle part of the upper die is provided with an injection port communicated with an injection machine, and the injection port is communicated with the upper cavity; and the lower die is provided with a power mechanism for pushing out the injection molding piece.

Through the arrangement, the upper die and the lower die are connected, the molten raw material body is injected into the injection port through the injection machine, and the molten raw material body moves into the safety cap cavity; standing for a period of time, and cooling and molding the raw material body to be melted; mould and lower mould in the separation, rethread power unit pushes away the injection molding, compares in the manual work and takes out the injection molding, and this scheme replaces the manual work through machinery and realizes the automatic injection molding that takes out, effectively avoids the damage or the deformation of injection molding.

Further, the power mechanism comprises an air cylinder and a plurality of push rods, the bottom of the lower die is provided with a groove and a plurality of chutes communicated with the groove and the lower cavity, the air cylinder is fixedly connected in the groove, and an output shaft of the air cylinder is connected with a push plate; the push rod slides in the sliding groove and is fixedly connected with the push plate.

Through the arrangement, after the injection molding piece is cooled and formed, the upper die and the lower die are separated; starting the air cylinder, driving the push plate to move upwards by an output shaft of the air cylinder, simultaneously pushing the push plates by the push plates, and simultaneously pushing the injection molding parts by the push rods so as to separate the injection molding parts from the lower die, thus obtaining the molded safety helmet injection molding parts; the injection molding piece is taken automatically, so that the damage or deformation of the injection molding piece is avoided, and the working efficiency is improved.

Furthermore, an upper swing arm is hinged to the side wall of the upper die, and a lug is arranged on the upper swing arm; a lower swing arm is hinged to the side wall of the lower die, and a clamping groove used for being clamped with the bump is formed in the lower swing arm; an upper threaded hole is formed in the side wall of the upper die, an upper threaded rod is connected to the inner thread of the upper threaded hole, and an upper through hole for the upper threaded rod to penetrate through is formed in the upper swing arm; and a lower threaded hole is formed in the side wall of the lower die, a lower threaded rod is connected to the inner thread of the lower threaded hole, and a lower through hole for the lower threaded rod to pass through is formed in the lower swing arm.

Through the arrangement, when the die is attached to the lower die, the upper swing arm and the lower swing arm are swung, so that the upper swing arm is attached to the upper die, and the upper through hole is communicated with the upper threaded hole; the lower swing arm is attached to the lower die, and the lower through hole is communicated with the lower threaded hole; the lug on the upper swing arm is clamped with the clamping groove on the lower swing arm, so that the upper swing arm and the lower swing arm are positioned, and the upper die and the lower die are positioned. The upper threaded rod penetrates through the upper through hole and extends into the upper threaded hole, and the upper threaded rod is rotated to be in threaded connection with the upper threaded hole; the lower threaded rod penetrates through the lower through hole and extends into the lower threaded hole, and the lower threaded rod is rotated to be in threaded connection with the lower threaded hole; because the threaded connection structure has self-locking performance, the stability of positioning the upper limiting arm and the lower limiting arm is improved.

Furthermore, an upper annular groove is formed in the upper threaded rod, an upper limiting block is connected in the upper annular groove in a sliding mode, an upper limiting arm is obliquely arranged on the upper limiting block, and the upper swing arm is located on the motion track of the upper limiting arm; the lower threaded rod is provided with a lower annular groove, a lower limiting block is connected in the lower annular groove in a sliding mode, a lower limiting arm is obliquely arranged on the lower limiting block, and the lower swing arm is located on the motion track of the lower limiting arm; and an elastic piece is sleeved between the upper threaded rod and the lower threaded rod.

Through the arrangement, the upper limiting block slides in the upper ring groove, and when the upper threaded rod rotates, the upper limiting block is always positioned below the upper ring groove due to gravity; the upper threaded rod continues to rotate into the upper threaded hole, and when the upper limiting arm abuts against the upper swing arm, the upper threaded rod stops rotating; the positioning of the upper swing arm can be enhanced through the upper limiting arm; and, form the triangle-shaped structure by last threaded rod, last spacing arm and last swing arm, according to the stability of triangle-shaped structure, and then improve the stability to last swing arm location.

Because the lower limiting block slides in the lower ring groove, when the lower threaded rod rotates, the lower limiting block is always positioned below the lower ring groove due to gravity; the lower threaded rod continues to rotate into the lower threaded hole, and when the lower limiting arm abuts against the lower swinging arm, the lower threaded rod stops rotating; the lower limiting arm can be used for strengthening the positioning of the lower swing arm; and, form the triangle-shaped structure by lower threaded rod, lower spacing arm and lower swing arm, according to the stability of triangle-shaped structure, and then improve the stability to lower swing arm location.

The elastic piece is sleeved on the upper threaded rod and the lower threaded rod, so that the positioning effect on the upper threaded rod and the lower threaded rod is enhanced.

Furthermore, a cooling channel is arranged in the lower die, a fan is arranged on the side wall of the lower die, and a pipeline is arranged between the fan and the cooling channel.

Through the setting, start the fan, the air current that the fan produced continuously passes the cooling channel, and then continuously cools down, cools off the injection molding, shortens injection molding cooling shaping time.

Drawings

FIG. 1 is a front cross-sectional view of an injection molding apparatus according to an embodiment of the present invention;

FIG. 2 is a sectional view in partial section in the front view direction of the injection mechanism;

FIG. 3 is an enlarged view taken at A in FIG. 2;

FIG. 4 is a sectional view of a second injection molding mechanism of an embodiment of the injection molding apparatus of the present invention, partially cut in the front view direction.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the injection molding device comprises an upper die 1, a lower die 2, an upper die cavity 3, a lower die cavity 4, an injection molding opening 5, a cylinder 6, a push rod 7, a groove 8, a sliding groove 9, a push plate 10, a guide rod 11, a guide groove 12, an upper swing arm 13, a bump 14, a lower swing arm 15, a clamping groove 16, an upper threaded rod 17, an upper through hole 18, a lower threaded rod 19, a lower through hole 20, an upper annular groove 21, an upper limiting block 22, an upper limiting arm 23, a lower annular groove 24, a lower limiting block 25, a lower limiting arm 26, an elastic piece 27, a cooling channel 28, a fan 29, a pipeline 30, a box body 31, a feeding pipe 32, a discharging pipe 33, a screen 34, a valve 35, an injection machine 36, a motor 37, a sliding plate 38, a rotating shaft 39, a cam 40, a first spring 41, a mixing barrel 42, a discharging port 43, a through hole 44, a rack 45, a second spring 46, a feeding port 47.

Example one

A production process for safety helmets comprises the following steps:

(1) selecting a polyformaldehyde raw material: selecting the following raw materials in parts by weight: 70 parts of trioxymethylene, 20 parts of dioxolane and 10 parts of boron trifluoride diethyl etherate;

(2) mixing polyformaldehyde raw materials: uniformly mixing the polyformaldehyde raw materials in the step (1), and reacting for 2.5 hours at the temperature of 68 ℃ to obtain polyformaldehyde;

(3) selecting injection molding raw materials: selecting the following raw materials in parts by weight: 80 parts of polyformaldehyde, 16 parts of nano mica sheet powder, 1 part of nano magnesium aluminum oxide and 3 parts of zinc oxide;

The safety helmet prepared by the embodiment has good ultraviolet radiation resistance, strong impact resistance and good cooling performance.

Wherein, the step (4) and the step (5) adopt an injection molding device for processing.

Substantially as shown in figures 1, 2 and 3: the injection molding device comprises a base, wherein a stirring mechanism and an injection molding mechanism are arranged on the base, the stirring mechanism comprises a box body 31, the top of the box body 31 is connected with a plurality of feeding pipes 32, and the bottom of the box body 31 is connected with a discharging pipe 33; the top of the discharge pipe 33 is fixedly connected with a screen 34, the middle part of the discharge pipe 33 is provided with a valve 35, and the bottom of the discharge pipe 33 is communicated with an injection machine 36; a first-stage mixing unit and a second-stage mixing unit for mixing injection molding raw materials are arranged in the box body 31.

The first-stage mixing unit comprises a motor 37 and a sliding plate 38, the motor 37 is fixedly connected to the outer wall of the box body 31, an output shaft of the motor 37 is connected with a rotating shaft 39, and a cam 40 is fixedly connected to the rotating shaft 39; the sliding plate 38 is slidably connected to the side wall of the box 31, and a first spring 41 is fixedly connected between the sliding plate 38 and the box 31; a mixing barrel 42 for collecting injection molding raw materials is fixedly connected to the sliding plate 38, and the mixing barrel 42 is positioned in the box body 31; the bottom of the mixing barrel 42 is provided with a discharge hole 43, and the sliding plate 38 is provided with a through hole 44 communicated with the discharge hole 43; the end of the slide plate 38 remote from the mixing tub 42 abuts the cam 40.

A rack 45 is connected to the side wall of the box 31 in a sliding manner, and a second spring 46 is fixedly connected between the rack 45 and the box 31; a plurality of feed inlets 47 are formed on the rack 45, and the feed inlets 47 and the feed pipes 32 are arranged in a staggered manner; the rack 45 is positioned above the sliding plate 38, and the bottom of the rack 45 is abutted against the top of the mixing barrel 42; a sector gear 48 meshed with the rack 45 is fixedly connected to the rotating shaft 39.

The second-stage mixing unit comprises a linkage shaft 49 and a driven bevel gear 50 fixedly connected to the linkage shaft 49, a stirring arm 51 is fixedly connected to the linkage shaft 49, and the stirring arm 51 is positioned in the box body 31; the linkage shaft 49 is rotatably connected to the side wall of the box body 31, and the linkage shaft 49 is positioned below the sliding plate 38; a drive bevel gear 52 engaged with the driven bevel gear 50 is fixedly connected to the rotating shaft 39.

The injection molding mechanism comprises an upper mold 1 and a lower mold 2, an upper cavity 3 is formed in the bottom of the upper mold 1, a lower cavity 4 is formed in the top of the lower mold 2, and the upper cavity 3 and the lower cavity 4 form a safety helmet cavity; the middle part of the upper die 1 is provided with an injection molding port 5 communicated with an injection machine, the width of the injection molding port 5 is gradually reduced from top to bottom, and the injection molding port 5 is communicated with the upper cavity 3.

A power mechanism for pushing out the injection molding piece is arranged on the lower die 2, the power mechanism comprises a cylinder 6 and a plurality of push rods 7, and the bottom of the lower die 2 is provided with a groove 8 and a plurality of sliding chutes 9 communicated with the groove 8; the cylinder 6 is fixedly connected on the groove 8, and a push plate 10 is welded on an output shaft of the cylinder 6; the push rods 7 slide in the sliding grooves 9, and the push rods 7 are welded with the top of the push plate 10.

The bottom welding of going up mould 1 has guide bar 11, and the guide way 12 that is used for guide bar 11 to stretch into is seted up at the top of lower mould 2, and when going up mould 1 and the laminating of lower mould 2, guide bar 11 is located guide way 12.

An upper swing arm 13 is hinged to the left side wall of the upper die 1, and a bump 14 is welded on the upper swing arm 13; the left side wall of the lower die 2 is hinged with a lower swing arm 15, and the lower swing arm 15 is provided with a clamping groove 16 for clamping with the convex block 14. An upper threaded hole is formed in the left side wall of the upper die 1, an upper threaded rod 17 is connected to the upper threaded hole in a threaded manner, an upper through hole 18 for the upper threaded rod 17 to penetrate through is formed in the upper swing arm 13, and when the upper swing arm 13 swings to be attached to the left side wall of the upper die 1, the upper through hole 18 is communicated with the upper threaded hole; a lower threaded hole is formed in the left side wall of the lower die 2, a lower threaded rod 19 is connected to the lower threaded hole in an internal thread mode, a lower through hole 20 through which the lower threaded rod 19 penetrates is formed in the lower swing arm 15, and when the lower swing arm 15 swings to be attached to the left side wall of the lower die 2, the lower through hole 20 is communicated with the lower threaded hole.

An upper annular groove 21 is formed in the upper threaded rod 17, an upper limiting block 22 is connected in the upper annular groove 21 in a sliding mode, an upper limiting arm 23 is welded on the upper limiting block 22 in an inclined mode, and the upper swing arm 13 is located on the motion track of the upper limiting arm 23; lower annular groove 24 has been seted up on the threaded rod 19 down, and lower ring inslot 24 sliding connection has lower spacing piece 25, and the slope welding of lower spacing piece 25 has lower spacing arm 26, and lower swing arm 15 is located the movement track of lower spacing arm 26. An elastic member 27 is sleeved between the upper threaded rod 17 and the lower threaded rod 19, and the elastic member 27 is an elastic belt in the embodiment.

The specific implementation process is as follows:

adding four injection molding raw materials of polyformaldehyde, nano-mica sheet powder, nano-magnesium aluminum oxide and zinc oxide into the feeding pipe 32 respectively; the motor 37 is started, an output shaft of the motor 37 drives the rotating shaft 39 to rotate, the rotating shaft 39 drives the sector gear 48, the cam 40 and the driving bevel gear 52 to rotate, the second spring 46 is matched through intermittent meshing of the sector gear 48 and the rack 45 to drive the rack 45 to reciprocate along the horizontal direction, when the rack 45 moves leftwards, a feed port 47 on the rack 45 is communicated with the feed pipe 32, so that four injection molding raw materials fall into the mixing barrel 42 through the feed port 47, the four injection molding raw materials can be quantitatively controlled to enter the mixing barrel 42 to be mixed, and the mixing effect is enhanced; because the rotating shaft 39 drives the cam 40 to rotate, the intermittent extrusion sliding plate 38 of the convex part of the cam 40 is matched with the first spring 41 to drive the sliding plate 38 to reciprocate along the horizontal direction, and further drive the mixing barrel 42 on the sliding plate 38 to reciprocate along the horizontal direction, so that the four injection molding raw materials are preliminarily mixed in the mixing barrel 42.

The four injection molding raw materials which are primarily mixed move towards the bottom of the box body 31 through the discharge hole 43 and the through hole 44; since the rotating shaft 39 drives the driving bevel gear 52 to rotate, the driven bevel gear 50 drives the linkage shaft 49 to rotate through the meshing of the driving bevel gear 52 and the driven bevel gear 50; the universal driving shaft 49 drives the stirring arm 51 to stir and mix the four injection molding raw materials at the bottom of the box body 31 again, and finally a raw material body is obtained; the raw material bodies are collected in the discharge pipe 33 through the screen 34, and the screen 34 can prevent the raw material bodies in a pile or a sphere from entering the discharge pipe 33, and the raw material bodies in a pile or a sphere can be dispersed by the stirring arm 51.

Before injection molding, the upper die 1 is attached to the lower die 2, so that the upper die cavity 3 is communicated with the lower die cavity 4 to form a safety helmet die cavity; meanwhile, the guide rod 11 extends into the guide groove 12, so that the upper die 1 and the lower die 2 are prevented from relative displacement in the horizontal direction; and at this moment, the tops of the push rods 7 are all positioned at the communication part of the lower cavity 4 and the groove 8.

Swinging the upper swing arm 13 and the lower swing arm 15 to enable the upper swing arm 13 to be attached to the upper die 1, and enabling the upper through hole 18 to be communicated with the upper threaded hole; the lower swing arm 15 is attached to the lower die 2, and the lower through hole 20 is communicated with the lower threaded hole; in addition, the bump 14 on the upper swing arm 13 is clamped with the clamping groove 16 on the lower swing arm 15, so that the upper swing arm 13 and the lower swing arm 15 are positioned, and the upper die 1 and the lower die 2 are connected and positioned.

The upper threaded rod 17 penetrates through the upper through hole 18 and extends into the upper threaded hole, and the upper threaded rod 17 is rotated to be in threaded connection with the upper threaded hole; because the upper limiting block 22 slides in the upper ring groove 21, when the upper threaded rod 17 rotates, the upper limiting block 22 is always positioned below the upper ring groove 21 due to gravity; the upper threaded rod 17 continues to rotate into the upper threaded hole, and when the upper limiting arm 23 abuts against the upper swing arm 13, the upper threaded rod 17 stops rotating; the positioning of the upper swing arm 13 can be enhanced through the upper limiting arm 23, and the stability of positioning the upper limiting arm 23 can be improved through the matching of the upper threaded rod 17 and the upper threaded hole due to the fact that the threaded connection structure has self-locking performance. In addition, a triangular structure is formed by the upper threaded rod 17, the upper limiting arm 23 and the upper swing arm 13, and the stability of positioning the upper swing arm 13 is further improved according to the stability of the triangular structure.

The lower threaded rod 19 penetrates through the lower through hole 20 and extends into the lower threaded hole, and the lower threaded rod 19 is rotated to be in threaded connection with the lower threaded hole; because the lower limiting block 25 slides in the lower ring groove 24, when the lower threaded rod 19 rotates, the lower limiting block 25 is always positioned below the lower ring groove 24 due to gravity; the lower threaded rod 19 continues to rotate into the lower threaded hole, and when the lower limiting arm 26 abuts against the lower swing arm 15, the lower threaded rod 19 stops rotating; the lower limit arm 26 can strengthen the positioning of the lower swing arm 15, and the threaded connection structure has self-locking performance, so that the stability of positioning the lower limit arm 26 can be improved by matching the lower threaded rod 19 with the lower threaded hole. In addition, the lower threaded rod 19, the lower limit arm 26 and the lower swing arm 15 form a triangular structure, and the stability of positioning the lower swing arm 15 is further improved according to the stability of the triangular structure.

And the elastic piece 27 is sleeved on the upper threaded rod 17 and the lower threaded rod 19, so that the positioning effect on the upper threaded rod 17 and the lower threaded rod 19 is enhanced.

Opening the valve 35, introducing the raw material body into the injection machine 36, heating and melting the raw material body by the injection machine 36 to be in a flowing state, then injecting the raw material body into the injection port 5, and moving the melted raw material body to the cavity of the safety helmet; standing for a period of time, and cooling and molding the raw material body to be melted; the elastic piece 27 is taken down, the upper threaded rod 17 and the lower threaded rod 19 are rotated out and taken down, the upper swing arm 13 and the lower swing arm 15 are separated, and the upper die 1 is further separated from the lower die 2; the cylinder 6 is started, the output shaft of the cylinder 6 drives the push plate 10 to move upwards, the push plate 10 simultaneously pushes the push rods 7, and the push rods 7 simultaneously push the injection molding piece, so that the injection molding piece is separated from the lower die 2, and the molded safety helmet injection molding piece is obtained.

Example two

As shown in fig. 4, the structure and implementation of the second embodiment are substantially the same as those of the first embodiment, and the difference is that: a cooling channel 28 is formed in the lower die 2, and the cooling channel 28 is arranged around the lower cavity; a fan 29 is fixedly connected to the side wall of the lower die 2, and a pipeline 30 is connected between the fan 29 and the cooling channel 28.

The specific implementation process is as follows:

the fan 29 is started, the airflow generated by the fan 29 continuously passes through the cooling channel 28, and then the injection molding piece is continuously cooled, and the cooling molding time of the injection molding piece is shortened.

The foregoing is merely an example of the present invention and common general knowledge in the art of specific structures and/or features of the invention has not been set forth herein in any way. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. A production process for safety helmets is characterized in that: the method comprises the following steps:

(4) mixing injection molding raw materials: the injection molding device comprises a base, wherein a stirring mechanism, an injection machine and an injection molding mechanism which are communicated with each other are arranged on the base, and the injection molding raw material in the step (3) is put into the stirring mechanism and uniformly mixed to obtain a raw material body; the stirring mechanism comprises a box body, the top of the box body is provided with a plurality of feeding pipes, and the bottom of the box body is provided with a discharging pipe; the top of the discharge pipe is provided with a screen, the middle of the discharge pipe is provided with a valve, and the bottom of the discharge pipe is communicated with an injection machine; a primary mixing unit and a secondary mixing unit for mixing injection molding raw materials are arranged in the box body; the primary mixing unit comprises a motor and a sliding plate, the motor is fixedly connected to the outer wall of the box body, an output shaft of the motor is connected with a rotating shaft, and a cam is arranged on the rotating shaft; the sliding plate is connected to the side wall of the box body in a sliding mode, and a first spring is arranged between the sliding plate and the box body; a mixing barrel for collecting injection molding raw materials is arranged on the sliding plate and is positioned in the box body; a discharge port is formed in the bottom of the mixing barrel, and a through hole communicated with the discharge port is formed in the sliding plate; one end of the sliding plate, which is far away from the mixing barrel, is abutted against the cam; a rack is connected to the side wall of the box body in a sliding manner, and a second spring is arranged between the rack and the box body; a plurality of feed inlets are formed in the rack, and the feed inlets and the feed pipes are arranged in a staggered manner; the rack is positioned above the sliding plate, and the bottom of the rack is abutted against the mixing barrel; the rotating shaft is provided with a sector gear meshed with the rack; the secondary mixing unit comprises a linkage shaft and a driven bevel gear fixedly connected to the linkage shaft, and a stirring arm is arranged on the linkage shaft and is positioned in the box body; the linkage shaft is rotatably connected to the side wall of the box body and is positioned below the sliding plate; a driving bevel gear meshed with the driven bevel gear is arranged on the rotating shaft;

2. A process for producing a crash helmet according to claim 1, wherein: the injection molding mechanism comprises an upper die and a lower die, and the upper die is detachably connected with the lower die; an upper cavity is arranged at the bottom of the upper die, a lower cavity is arranged at the top of the lower die, and the upper cavity and the lower cavity form a safety cap cavity; the middle part of the upper die is provided with an injection port communicated with an injection machine, and the injection port is communicated with the upper cavity; and the lower die is provided with a power mechanism for pushing out the injection molding piece.

3. A process for producing crash helmets according to claim 2, wherein: the power mechanism comprises an air cylinder and a plurality of push rods, the bottom of the lower die is provided with a groove and a plurality of sliding chutes communicated with the groove and the lower cavity, the air cylinder is fixedly connected in the groove, and an output shaft of the air cylinder is connected with a push plate; the push rod slides in the sliding groove and is fixedly connected with the push plate.

4. A process for producing crash helmets according to claim 3, wherein: an upper swing arm is hinged to the side wall of the upper die, and a lug is arranged on the upper swing arm; a lower swing arm is hinged to the side wall of the lower die, and a clamping groove used for being clamped with the bump is formed in the lower swing arm; an upper threaded hole is formed in the side wall of the upper die, an upper threaded rod is connected to the inner thread of the upper threaded hole, and an upper through hole for the upper threaded rod to penetrate through is formed in the upper swing arm; and a lower threaded hole is formed in the side wall of the lower die, a lower threaded rod is connected to the inner thread of the lower threaded hole, and a lower through hole for the lower threaded rod to pass through is formed in the lower swing arm.

5. The process for producing a crash helmet according to claim 4, wherein: an upper annular groove is formed in the upper threaded rod, an upper limiting block is connected in the upper annular groove in a sliding mode, an upper limiting arm is obliquely arranged on the upper limiting block, and the upper swing arm is located on the motion track of the upper limiting arm; the lower threaded rod is provided with a lower annular groove, a lower limiting block is connected in the lower annular groove in a sliding mode, a lower limiting arm is obliquely arranged on the lower limiting block, and the lower swing arm is located on the motion track of the lower limiting arm; and an elastic piece is sleeved between the upper threaded rod and the lower threaded rod.

6. The process for producing a crash helmet according to claim 5, wherein: be equipped with the cooling channel in the lower mould, be equipped with the fan on the lateral wall of lower mould, and be equipped with the pipeline between fan and the cooling channel.