CN112959621A

CN112959621A - Exhaust mechanism of core injection chair mold

Info

Publication number: CN112959621A
Application number: CN202110134426.6A
Authority: CN
Inventors: 黄祖权
Original assignee: Hangzhou Yutong Cultural Creative Co ltd
Current assignee: Hangzhou Yutong Cultural Creative Co ltd
Priority date: 2021-02-01
Filing date: 2021-02-01
Publication date: 2021-06-15

Abstract

The invention discloses an exhaust mechanism of a core injection chair mold, which comprises a fixed mold plate, a cavity plate, a sprue bush, a sprue, a cavity, a guide sleeve, a guide pillar, a movable mold plate, a core, a material ejection structure and an exhaust mechanism, wherein the fixed mold plate is fixed on the fixed mold plate; the ejection structure comprises a main air pressure bin, a pressing piston, a working spring, a buffer bin, an ejection hole, an ejection rod, an ejector rod fixing plate, a reset hole, a reset rod, an auxiliary air pressure bin, a reset piston, a first connecting pipe for connecting the main air pressure bin and the buffer bin and a second connecting pipe for connecting the auxiliary air pressure bin and the buffer bin; the reset rod is fixedly connected to the ejector rod fixing plate; through the linkage of the material ejecting structure and the exhaust mechanism, the automatic material ejecting and the overflow exhaust of the cavity in the integral molding process of the injection molding chair can be realized, and the molding quality of the injection molding chair is improved.

Description

Exhaust mechanism of core injection chair mold

Technical Field

The invention belongs to the technical field of injection molds, and particularly relates to an exhaust mechanism of a core injection chair mold.

Background

The integrated injection molding chair is high in yield, changeable in appearance and low in cost, is more and more favored by people, and is widely used in office areas of hotel rooms and high-grade office buildings, the integrated injection molding chair is formed by heating, melting and plasticizing plastic particles in a screw injection molding machine, injecting the plastic particles into a mold, and pressurizing and plasticizing the plastic particles, and because the specific surface area of the injection molding chair is large, a mold core 19 and a mold cavity 14 of the injection molding mold for processing are large, so that corners in the mold cavity 14 are large, gas trapping phenomenon is easily caused by unsmooth air exhaust during injection molding, and the quality of the injection molding chair is reduced or injection molding fails; in order to solve the phenomenon, the conventional method for solving the problem is to reduce injection pressure and increase back pressure, but the method solves the problem of air trapping and brings new problems, for example, the flash of a forming chair is very serious, so that troubles are brought to later processing, and simultaneously, a large amount of waste of raw materials is caused.

Disclosure of Invention

The invention provides an exhaust mechanism of a core injection molding chair mold, which can automatically feed and intelligently remove skins in order to overcome the defects of the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme: an exhaust mechanism of a core injection chair mold comprises a fixed mold plate, a cavity plate fixedly connected with the fixed mold plate, a sprue bush fixedly connected with the fixed mold plate, a sprue arranged on the cavity plate, a cavity arranged on the cavity plate, a plurality of guide sleeves fixedly connected with the fixed mold plate, guide posts slidably connected with the guide sleeves, a movable mold plate fixedly connected with the guide posts, a core plate fixedly connected with the movable mold plate, a core arranged on the core plate, a material ejecting structure arranged on the core plate and an exhaust mechanism arranged on the core plate; the method is characterized in that: the ejection structure comprises a main air pressure bin arranged on the core plate, a pressing piston slidably connected to the main air pressure bin, a working spring arranged in the main air pressure piston, a buffer bin arranged on the core plate, an ejection hole arranged on the core, an ejection rod slidably connected to the ejection hole, an ejection rod fixing plate fixedly connected to the ejection rod, a reset hole arranged on the core plate, a reset rod slidably connected to the reset hole, an auxiliary air pressure bin arranged on the core plate, a reset piston fixedly connected to the reset rod and slidably connected to the auxiliary air pressure bin, a first connecting pipe connecting the main air pressure bin and the buffer bin, and a second connecting pipe connecting the auxiliary air pressure bin and the buffer bin; the reset rod is fixedly connected to the ejector rod fixing plate; when injection molding is started, the mold core and the mold cavity start to be precisely buckled under the action of the guide pillar and the guide sleeve, the pressing piston receives the pressure of the mold cavity plate, the pressing piston slides downwards along the main air pressure bin, the working spring is compressed, the air pressure in the main air pressure bin rises, further air pressure is transmitted to the buffer bin through the first connecting pipe and is further transmitted to the auxiliary air pressure bin through the second connecting pipe, the air pressure in the auxiliary air pressure bin rises to drive the reset piston to move downwards, further, the reset rod drives the ejector rod fixing plate to fall, further, the ejector rod retreats into the ejector hole, the screw injection molding machine enables molten plastic to enter the straight pouring gate through the sprue bush and further enter the mold cavity to start filling the mold cavity, after filling is finished, the mold core and the mold cavity start to be separated under the action of the injection molding machine, further, the working spring starts to recover to drive the pressing piston to move upwards, and the air pressure in the main air pressure, further, the air pressure in the buffer bin is reduced, further, the air pressure in the auxiliary air pressure bin is reduced, the reset piston drives the reset rod and the ejector rod fixing plate to ascend, the ejector rod ascends, and a finished product injection molding chair wrapped on the mold core is ejected; through having set up main pneumatic chamber and working spring, can realize that the liftout pole is automatic when closing and has retracted the liftout hole, guaranteed normal compound die and mould plastics, and when the die sinking, under the effect of atmospheric pressure, the liftout pole can auto-eject, will mould plastics the chair from the surface of core under, accomplish automatic discharge, do not need extra power to provide, saved the energy, reduced the electric power cost, degree of automation is high, can show promotion machining efficiency.

The exhaust mechanism comprises a first overflow groove arranged below the cavity, a second overflow groove arranged above the cavity, a starting rack fixedly connected with the pressing piston, a driving hole arranged on the core plate, a driving shaft rotatably connected with the driving hole, a driving gear rotatably connected with the driving shaft, a powerful torsion spring connecting the driving shaft and the driving gear, a negative pressure bin arranged inside the core plate, a fixed rod fixedly connected with the negative pressure bin, a guide rod slidably connected with the fixed rod, a return spring sleeved on the guide rod, a pressurizing plate fixedly connected with the guide rod and slidably connected with the negative pressure bin, a starting hole arranged on the core plate, a limiting rod slidably connected with the starting hole, a limiting groove arranged on the driving shaft, a notch groove arranged on the limiting rod, a connecting rope connecting the pressurizing plate and the driving shaft, a first overflow groove arranged on the lower part of the cavity, a second overflow groove arranged on the upper part of the cavity, the first air exhaust pipe is communicated with the first overflow groove and the negative pressure bin, and the second air exhaust pipe is communicated with the second overflow groove and the negative pressure bin; when the die is closed, the pressing piston slides downwards along the main air pressure bin to drive the driving rack to move downwards, meanwhile, the limiting rod slides downwards, the limiting rod slides in the limiting groove, the driving shaft is limited and cannot rotate, the driving gear rotates under the meshing action of the gear, the powerful torsion spring deforms and starts to store energy, when the core is completely buckled with the die cavity, the notch groove is overlapped with the limiting groove, the limiting effect of the driving shaft is relieved, the driving shaft is driven to rotate under the action of the powerful torsion spring, further, when the connecting rope starts to be wound on the driving shaft, the guide rod drives the pressurizing plate to move backwards, the air pressure in the negative pressure bin is reduced, the air in the die cavity starts to enter the negative pressure groove through the first overflow groove and the second overflow groove through the first air exhaust pipe and the second air exhaust pipe, and the die cavity is in an approximately vacuum state; the negative pressure bin is arranged to drain air reserved in the cavity, so that the air pressure in the cavity is reduced, the injection molding work is facilitated to be carried out, the cavity in the negative pressure state can be used for processing injection molding pieces with more complicated shapes, the air trapping phenomenon cannot occur, and the manufactured injection molding chair is small in residual stress, compact in structure, high in quality and high in structural strength; meanwhile, due to the arrangement of the negative pressure bin, air in the cavity can be easily exhausted without reducing the injection pressure to ensure an exhaust gap, so that the fit gap between the cavity plate and the core plate can be further reduced, thereby reducing the generation of flash, improving the quality of products and reducing the waste of raw materials; at the beginning of the die assembly action, the limiting rod is at the highest position under the action of the spring, the notch groove and the limiting groove on the driving shaft are staggered mutually, the driving shaft cannot rotate under the action of the limiting rod, but the driving gear rotates all the time and transmits the torque to the powerful torsion spring to be stored, the notch groove and the limiting groove coincide when the core is completely buckled with the cavity, at the moment, the driving gear is limited to be incapable of rotating, the energy stored by the powerful torsion spring is released to the driving shaft to drive the driving shaft to rotate, and then the cavity starts to be pumped, so that the delay control of air pumping is realized, the energy of the torsion spring is prevented from being released before the core cavity is not completely closed, and the energy is ensured to be completely used for effective work.

The first exhaust pipe is arranged at the front of the interface position of the negative pressure cabin, and the second exhaust pipe is arranged at the back of the interface position of the negative pressure cabin; when air extraction is started, the pressure increasing plate is positioned between the interface position of the first air extracting pipe and the negative pressure bin and the interface position of the second air extracting pipe and the negative pressure bin, the pressure increasing plate moves backwards, the air pressure in front of the pressure increasing plate is reduced, the air pressure behind the pressure increasing plate is increased, further, air flow flows into the cavity from the part behind the pressure increasing plate through the second air extracting pipe, the air in the cavity flows into the negative pressure bin through the first exhaust pipe to form the directional flow of the air in the cavity, the molten material flow enters the cavity and is firstly filled downwards under the flow guide effect of the air flow, after the lower half part of the cavity is filled, the pressurizing plate moves to the interface position of the second air exhaust pipe and the negative pressure bin, the first air exhaust pipe and the second air exhaust pipe generate suction force at the same time, air at the upper half part of the cavity enters the negative pressure bin along the second air exhaust pipe, and material flow starts to be filled upwards until the cavity is filled; through the adjustment of two interface positions, realized the order and bled, further the water conservancy diversion effect through the air current, make the packing of whole material stream become orderly, rather than filling at random, on the one hand because discharge smoothly with the gas in the die cavity, reduce the gas trapping phenomenon, on the other hand, can effectively avoid the production of weld mark to the guide effect of material stream, improves the shaping quality of product.

A pattern drawing angle is arranged at the joint of the first air exhaust pipe and the second air exhaust pipe at the overflow groove; when the mold is opened, the gas in the negative pressure bin can be completely discharged under the action of the return spring, the gas pressure of a strand of liftout is generated, the demolding of the injection molding chair is facilitated, and the draft angle can ensure that the leftover materials can be smoothly released from the exhaust tube and remain on the injection molding chair when the demolding is performed.

The cavity arranged in the core plate has good sealing performance.

In summary, the invention has the following advantages: when the mold is opened, the ejector rod can automatically pop out under the action of air pressure, the injection molding chair is ejected from the surface of the mold core, automatic discharging is completed, additional power is not needed, energy is saved, electric power cost is reduced, the automation degree is high, and the processing efficiency can be obviously improved; the negative pressure bin is arranged to drain air reserved in the cavity, so that the air pressure in the cavity is reduced, the injection molding work is facilitated to be carried out, the cavity in the negative pressure state can be used for processing injection molding pieces with more complicated shapes, the air trapping phenomenon cannot occur, and the manufactured injection molding chair is small in residual stress, compact in structure, high in quality and high in structural strength;

realized the order and bled, through the water conservancy diversion effect of air current, made the packing of whole material stream become orderly, rather than filling at random, on the one hand because discharge smoothly with the gas of die cavity, reduce the gas trapping phenomenon, on the other hand, can effectively avoid the production of weld mark to the guide effect of material stream, improves the shaping quality of product.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a top view of the present invention.

Fig. 3 is a cross-sectional view taken along a-a of fig. 2.

Fig. 4 is a cross-sectional view taken along B-B of fig. 2.

Fig. 5 is an exploded view of the present invention.

Fig. 6 is a perspective view of the exhaust mechanism of the present invention.

Fig. 7 is a schematic view of a mold cavity according to the present invention.

FIG. 8 is a schematic view of a core of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention.

As shown in fig. 1-8, an exhaust mechanism 3 of a core 19 injection chair mold comprises a fixed mold plate 1, a cavity plate 11, a sprue bush 12, a sprue 13, a cavity 14, a guide sleeve 15, a guide pillar 16, a movable mold plate 17, a core plate 18, a liftout structure 2 and an exhaust mechanism; the cavity plate 11 is fixedly connected with the fixed mold plate 1; the sprue bush 12 is fixedly connected with the fixed die plate 1; the sprue 13 is arranged on the cavity plate 11; the cavity 14 is arranged on the cavity plate 11; four guide sleeves 15 are fixedly connected to the fixed die plate 1; the guide post 16 is slidably connected to the guide sleeve 15; the movable die plate 17 is fixedly connected to the guide post 16; the core plate 18 is fixedly connected to the movable mould plate 17; the core 19 is disposed on the core plate 18; the liftout structure 2 is arranged in the core plate 18; the exhaust mechanism 3 is arranged on the core plate 18; the material ejecting structure 2 comprises a main air pressure bin 21, a pressing piston 22, a working spring 23, a buffer bin 24, an ejecting hole 25, an ejecting rod 26, an ejecting rod fixing plate 27, a resetting hole 28, a resetting rod 29, an auxiliary air pressure bin 210, a resetting piston 211, a first connecting pipe 212 and a second connecting pipe 213; the main air pressure bin 21 is arranged on the core plate 18; the pressing piston 22 is connected with the main air pressure bin 21 in a sliding mode; the working spring 23 is arranged in the main air pressure piston; the surge bin 24 is arranged on the core plate 18; the material ejecting hole 25 is arranged on the mold core 19; the ejector rod 26 is slidably connected to the ejector hole 25; the ejector rod fixing plate 27 is fixedly connected to the ejector rod 26; the reset hole 28 is formed in the core plate 18; the reset rod 29 is slidably connected to the reset hole 28; the auxiliary air pressure bin 210 is arranged on the core plate 18; the reset piston 211 is fixedly connected to the reset rod 29 and is slidably connected to the auxiliary air pressure chamber 210; the first connecting pipe 212 connects the main air pressure bin 21 and the buffer bin 24; the second connecting pipe 213 connects the sub air pressure chamber 210 and the surge chamber 24; the reset rod 29 is fixedly connected to the top rod fixing plate 27.

The exhaust mechanism 3 comprises a first overflow groove 31, a second overflow groove 32, a starting rack 33, a driving hole 34, a driving shaft 35, a driving gear 36, a strong torsion spring 37, a negative pressure bin 38, a fixing rod 39, a guide rod 310, a return spring 311, a pressure increasing plate 312, a starting hole 313, a limiting rod 314, a limiting groove 315, a notch groove 316, a connecting rope 317, a first exhaust pipe 318 and a second exhaust pipe 319; the first overflow groove 31 is arranged below the cavity 14; the second overflow groove 32 is arranged above the cavity 14; the starting rack 33 is fixedly connected to the pressing piston 22; the drive holes 34 are provided in the core plate 18; the drive shaft 35 is rotatably connected to the drive hole 34; the drive gear 36 is rotatably connected to the drive shaft 35; the strong torsion spring 37 connects the driving shaft 35 and the driving gear 36; the negative pressure bin 38 is arranged inside the core plate 18; the fixing rod 39 is fixedly connected to the negative pressure cabin 38; the guide rod 310 is slidably connected to the fixing rod 39; the return spring 311 is sleeved on the guide rod 310; the pressure increasing plate 312 is fixedly connected to the guide rod 310 and is slidably connected to the negative pressure cabin 38; the starting hole 313 is arranged in the core plate 18; the limiting rod 314 is slidably connected to the starting hole 313; the limiting groove 315 is arranged on the driving shaft 35; the notch groove 316 is arranged on the limiting rod 314; the connecting rope 317 connects the pressure increasing plate 312 and the driving shaft 35; the first exhaust pipe 318 is communicated with the first overflow trough 31 and the negative pressure bin 38; the second exhaust pipe 319 communicates the second overflow trough 32 with the negative pressure bin 38.

The first exhaust tube 318 is located at the front of the interface of the negative pressure chamber 38, and the second exhaust tube 319 is located at the back of the interface of the negative pressure chamber 38.

The first exhaust pipe 318 and the second exhaust pipe 319 are provided with a draft angle 320 at the connection of the overflow trough.

The cavity formed in the core plate 18 has good sealing properties.

The specific working process is as follows:

when injection molding is started, under the action of the guide post 16 and the guide sleeve 15, the mold core 19 and the mold cavity 14 start to be precisely buckled, the pressing piston 22 receives the pressure of the mold cavity plate 11, slides downwards along the main air pressure bin 21, the working spring 23 is compressed, the air pressure in the main air pressure bin 21 rises, further air pressure is transmitted to the buffer bin 24 through the first connecting pipe 212 and is further transmitted to the auxiliary air pressure bin 210 through the second connecting pipe 213, the air pressure in the auxiliary air pressure bin 210 rises, the resetting piston 211 is driven to move downwards, further, the resetting rod 29 drives the ejector rod fixing plate 27 to descend, further, the ejector rod 26 retreats into the ejector hole 25, the screw injection molding machine enters the molten plastic into the sprue channel 13 through the sprue bush 12 and further enters the mold cavity 14 to start to fill the mold cavity 14, after filling is finished, the mold core 19 and the mold cavity 14 start to separate and further, the working spring 23 starts to recover and drives the pressing piston 22 to move upwards, the air pressure in the main air pressure bin 21 is reduced, the air pressure in the buffer bin 24 is further reduced, the air pressure in the auxiliary air pressure bin 210 is further reduced, the reset piston 211 drives the reset rod 29 and the ejector rod fixing plate 27 to ascend, the ejector rod 26 ascends, and the finished injection molding chair wrapped on the mold core 19 is ejected;

when the mold closing is started, the pressing piston 22 slides downwards along the main air pressure bin 21 to drive the driving rack to move downwards, meanwhile, the limiting rod 314 slides downwards, the limiting rod 314 slides in the limiting groove 315, the driving shaft 35 is limited and can not rotate, under the meshing action of the gears, the driving gear 36 rotates, the strong torsion spring 37 deforms and starts to store energy, when the mold core 19 is completely buckled with the mold cavity 14, the position of the notch groove 316 is overlapped with that of the limiting groove 315, the limiting action of the driving shaft 35 is relieved, the driving shaft 35 is driven to rotate under the action of the strong torsion spring 37, further, when the connecting rope 317 starts to be wound on the driving shaft 35, the guide rod 310 drives the pressurizing plate 312 to move backwards, the air pressure in the negative pressure bin 38 is reduced, and the air in the mold cavity 14 starts to enter the negative pressure slot through the first overflow trough 31 and the second overflow trough 32 via the first air suction pipe 318 and the second, a state of approximate vacuum is formed in the cavity 14; the negative pressure bin 38 is arranged to guide the air reserved in the cavity 14, so that the air pressure in the cavity 14 is reduced, the injection molding work is facilitated, the cavity 14 in a negative pressure state can be used for processing injection molding parts with more complex shapes, the air trapping phenomenon cannot occur, and the manufactured injection molding chair is small in residual stress, compact in structure, high in quality and high in structural strength; meanwhile, due to the arrangement of the negative pressure bin 38, air in the cavity 14 can be easily exhausted without reducing injection pressure to ensure an exhaust gap, so that the fit gap between the cavity plate 11 and the core plate 18 can be further reduced, thereby reducing the generation of flash, improving the quality of products and reducing the waste of raw materials; at the beginning of the mold closing action, the limiting rod 314 is positioned at the highest position under the action of the spring, the notch groove 316 and the limiting groove 315 on the driving shaft 35 are staggered, the driving shaft 35 cannot rotate under the action of the limiting rod 314, but the driving gear 36 always rotates and transmits the torque to the powerful torsion spring 37 for storage, after the core 19 is completely buckled with the cavity 14, the notch groove 316 and the limiting groove 315 are overlapped, at the moment, the driving gear 36 is limited and cannot rotate, the energy stored in the powerful torsion spring 37 is released to the driving shaft 35 to drive the driving shaft 35 to rotate, and then the cavity 14 starts to be pumped, so that the delayed control of air pumping is realized, the energy of the torsion spring is prevented from being released before the cavity 14 of the core 19 is not completely closed, and the energy is ensured to be completely used for effective work and is simple and reliable and is not easy to damage;

when the air suction is started, the pressure increasing plate 312 is located between the interface position of the first air suction pipe 318 and the negative pressure cabin 38 and the interface position of the second air suction pipe 319 and the negative pressure cabin 38, the pressure increasing plate 312 moves backwards, the air pressure in front of the pressure increasing plate 312 decreases, the air pressure behind the pressure increasing plate 312 increases, further, the air flow flows into the cavity 14 from the rear part of the pressure increasing plate 312 through the second air suction pipe 319, the air in the cavity 14 flows into the negative pressure cabin 38 through the first air suction pipe 318, the directional flow of the air in the cavity 14 is formed, the molten material flow enters the cavity 14 and is firstly filled downwards under the guiding action of the air flow, after the lower half part of the cavity 14 is filled, the pressure increasing plate 312 moves to the interface position of the second air suction pipe 319 and the negative pressure cabin 38, the first air suction pipe 318 and the second air suction pipe 319 simultaneously generate suction force, the air in the upper half part of the cavity 14 enters the negative pressure cabin 38, the flow begins to fill upward until the cavity 14 is full;

when the mold is opened, the gas in the negative pressure bin 38 is completely discharged under the action of the return spring 311, a strand of material-ejecting gas pressure is generated, demolding of the injection molding chair is facilitated, and the draft angle 320 can ensure that leftover materials can be smoothly released from the exhaust pipe and remain on the injection molding chair when demolding is performed.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. An exhaust mechanism of a core injection chair mold comprises a fixed mold plate (1), a cavity plate (11) fixedly connected with the fixed mold plate (1), a sprue bush (12) fixedly connected with the fixed mold plate (1), a sprue (13) arranged on the cavity plate (11), a cavity (14) arranged on the cavity plate (11), a plurality of guide sleeves (15) fixedly connected with the fixed mold plate (1), guide posts (16) slidably connected with the guide sleeves (15), a movable mold plate (17) fixedly connected with the guide posts (16), a core plate (18) fixedly connected with the movable mold plate (17), a core (19) arranged on the core plate (18), a material ejection structure (2) arranged on the core plate (18), and an exhaust mechanism (3) arranged on the core plate (18); the method is characterized in that: liftout structure (2) including locating core board (18) have main atmospheric pressure storehouse (21), sliding connection in pressing piston (22) of main atmospheric pressure storehouse (21), locate working spring (23) in main atmospheric pressure storehouse (21), locate buffer bin (24) of core board (18), locate the liftout hole (25) of core (19), sliding connection in liftout pole (26) of liftout hole (25), fixed connection in ejector pin fixed plate (27) of liftout pole (26), locate reset hole (28) of core board (18), sliding connection in reset lever (29) of reset hole (28), locate the vice atmospheric pressure storehouse (210), fixed connection of core board (18) in reset lever (29) and sliding connection in reset piston (211) of vice atmospheric pressure storehouse (210), connect main atmospheric pressure storehouse (21) with the first connecting pipe (212) of buffer bin (24) and connect vice atmospheric pressure storehouse (210) A second connection pipe (213) with the surge bin (24); the reset rod (29) is fixedly connected to the ejector rod fixing plate (27).

2. A core (19) injection chair mold venting mechanism (3) as claimed in claim 1, wherein: the exhaust mechanism (3) comprises a first overflow groove (31) arranged below the cavity (14), a second overflow groove (32) arranged above the cavity (14), a starting rack (33) fixedly connected to the pressing piston (22), a driving hole (34) arranged on the core plate (18), a driving shaft (35) rotatably connected to the driving hole (34), a driving gear (36) rotatably connected to the driving shaft (35), a strong torsion spring (37) connected between the driving shaft (35) and the driving gear (36), a negative pressure bin (38) arranged inside the core plate (18), a fixing rod (39) fixedly connected to the negative pressure bin (38), a guide rod (310) slidably connected to the fixing rod (39), a return spring (311) sleeved on the guide rod (310), a pressurizing plate (312) fixedly connected to the guide rod (310) and slidably connected to the negative pressure bin (38), and a pressurizing plate (312), A starting hole (313) arranged in the core plate (18), a limiting rod (314) connected to the starting hole (313) in a sliding manner, a limiting groove (315) arranged in the driving shaft (35), a notch groove (316) arranged in the limiting rod (314), a connecting rope (317) connecting the pressure increasing plate (312) and the driving shaft (35), a first air exhaust pipe (318) communicating the first overflow groove (31) and the negative pressure bin (38), and a second air exhaust pipe (319) communicating the second overflow groove (32) and the negative pressure bin (38);

3. a core (19) injection chair mold venting mechanism (3) as claimed in claim 2, wherein: the first air exhaust pipe (318) is arranged at the front of the interface position of the negative pressure cabin (38), and the second air exhaust pipe (319) is arranged at the back of the interface position of the negative pressure cabin (38).

4. A core (19) injection chair mold venting mechanism (3) as claimed in claim 3, wherein: and a draft angle (320) is arranged at the joint of the first air exhaust pipe (318) and the second air exhaust pipe (319) at the overflow groove.

5. A core (19) injection chair mold venting mechanism (3) as claimed in claim 4, wherein: the cavity arranged in the core plate (18) has good sealing performance.