CN114801366A

CN114801366A - Laminated bulletproof glass

Info

Publication number: CN114801366A
Application number: CN202210400645.9A
Authority: CN
Inventors: 麻建明
Original assignee: Individual
Current assignee: Hebei Antaifuyuan Safety Equipment Manufacturer Co ltd
Priority date: 2021-04-09
Filing date: 2021-04-09
Publication date: 2022-07-29
Anticipated expiration: 2041-04-09
Also published as: CN112976726B; CN114801366B; CN112976726A

Abstract

The invention belongs to the technical field of bulletproof glass, and particularly relates to laminated bulletproof glass which comprises a pair of glass plates matched with each other; a gap is arranged between the two glass plates, a wavy buffer layer is arranged in the gap, the buffer layer consists of a metal net and a PVB layer wrapped on the outer surface of the metal net, the middle part of a convex part at one side of the buffer layer is bonded with the side wall of the glass plate, rigid press blocks are arranged at concave parts corresponding to one side of the buffer layer bonded with the glass plates, press plates are symmetrically connected to the side walls of the buffer layer corresponding to the inner sides of the press blocks, the buffer layers at the two sides can be compressed through the press plates when the press blocks are pressed, and the end parts of the two glass plates are connected through a plugging plate; the bullet-proof glass has the advantages that the bullet-proof glass is arranged, so that the buffer layer in the bullet-proof glass can effectively buffer the impact force of a bullet, and the situation that the bullet penetrates through the glass is prevented.

Description

Laminated bulletproof glass

Technical Field

The invention belongs to the technical field of bulletproof glass, and particularly relates to laminated bulletproof glass.

Background

The bulletproof glass is a composite material obtained by specially processing glass and high-quality engineering plastics, and the bulletproof glass produced by different manufacturers is different. But basically a layer of polycarbonate material is sandwiched between layers of ordinary glass, a process known as lamination. In this process, a substance similar to ordinary glass but thicker than ordinary glass is formed. Polycarbonate is a rigid transparent plastic. The thickness of the bullet-proof glass is between 7 mm and 75 mm. A bullet hitting the bullet-proof glass will break through the glass of the outer layer, but the polycarbonate glass material layer can absorb the energy of the bullet and prevent it from penetrating the inner glass layer.

The invention also provides an explosion-proof glass, which comprises a composite toughened glass unit, a bulletproof glass unit and a PC board, wherein the composite toughened glass unit, the bulletproof glass unit and the PC board are sequentially and reliably connected, an isolation groove and a sealant are arranged between the composite toughened glass unit and the bulletproof glass unit, a closed hollow layer is formed by the isolation groove, the bulletproof glass unit and the PC board are reliably connected through a PU film, the thickness of the PU film is not less than 1 mm, the composite sandwich glass unit is formed by compounding at least two layers of toughened glass through a PVB adhesive layer, the bulletproof glass unit is formed by compounding multiple layers of glass through a PVB adhesive layer, the thickness of the isolation groove is not less than 25 mm, the isolation groove is of a hollow structure, and a drying agent is filled in the bulletproof glass unit. This novel structure that adopts compound toughened glass unit, cavity unit, shellproof glass unit and PC to set up large-scale vacuum hollow layer between compound toughened glass unit, shellproof glass unit, very big reinforcing the whole off-load ability of glass, thereby reach the effect that promotes blast resistance ability.

However, the bullet-proof glass in the above technology has a limited buffering effect on bullets, so that the bullet-proof glass still can be punctured or broken under the impact of strong bullets, and the use effect and the service life of the bullet-proof glass are affected.

In view of the above, the invention provides laminated bulletproof glass and a preparation process thereof, and the structure of the bulletproof glass is arranged, so that the buffer layer in the bulletproof glass can play an effective buffer effect on the impact force of a bullet, and the situation that the bullet penetrates through the glass is prevented.

Disclosure of Invention

In order to make up the defects of the prior art, the invention provides the laminated bulletproof glass and the preparation process thereof, and the structure of the bulletproof glass is arranged, so that the buffer layer in the laminated bulletproof glass can play an effective buffer effect on the impact force of a bullet, and the situation that the bullet penetrates through the glass is prevented.

The technical scheme adopted by the invention for solving the technical problems is as follows: a laminated bulletproof glass comprises a pair of glass plates which are matched with each other; a gap is formed between the two glass plates, a wavy buffer layer is arranged in the gap, the buffer layer is composed of a metal net and a PVB layer wrapped on the outer surface of the metal net, the side wall of the buffer layer is attached to the side walls of the glass plates on the two sides, the middle part of the convex part on one side of the buffer layer is bonded with the side walls of the glass plates, rigid press blocks are arranged at the concave parts corresponding to one side of the buffer layer bonded with the glass plates, press plates are symmetrically connected to the side walls of the buffer layer corresponding to the inner sides of the press blocks, the buffer layers on the two sides can be compressed through the press plates when the press blocks are pressed, and the end parts of the two glass plates are connected through the plugging plates; when the bulletproof glass works, the buffering effect of the bulletproof glass in the prior art on bullets is limited, so that the bulletproof glass still can be punctured or broken under the impact of strong bullets, and the use effect and the service life of the bulletproof glass are influenced; when the bulletproof glass is used, the glass plate close to the pressing block faces to the side which is easy to be attacked, when an external bullet penetrates through the layer of glass plate, if the attack position of the bullet falls on the convex part of the buffer layer close to the pressing block, the bullet can drive the buffer layer capable of elastic deformation to compress towards two sides by extruding the impact position, so that the impact force of the bullet can be effectively buffered, the situation that the bullet penetrates through the glass is prevented, if the attack position of the bullet falls on the concave part of the buffer layer, the bullet can fall on the pressing block at the moment, the buffer layers on two sides are driven by the pressing block and the pressing plate to respectively compress towards two sides, so that the bullet can be effectively buffered when falling on any position of the buffer layer, and the bullet can be effectively buffered by arranging the pressing block matched with the buffer layer at the moment, the bulletproof effect of the glass is greatly improved; meanwhile, when the glass plate facing the attack position is broken, due to the fact that the glass plate is bonded with the PVB layer in a toughness mode, fragments of the glass plate can be bonded with the PVB layer after the glass plate is damaged, the glass can keep certain integrity, the glass fragments are prevented from falling to cause personal injury or property loss, and therefore the using effect of the bulletproof glass is further improved.

Preferably, the buffer layer and the side wall position opposite to the pressing block are respectively provided with an adsorption cavity, and the adsorption cavities can be adsorbed on the glass plate on one side; the during operation is through adsorbing the chamber on the glass board of one side with adsorbing for the buffer layer can drive when the atress warp and adsorb the chamber and relatively slide on the glass board, does not influence the effective work of buffer layer, and a plurality of relatively sealed cavities can be constituteed with this glass board to the buffer layer simultaneously, and gas in the sealed cavity this moment can play certain support and reverse effect to the deformation of the buffer layer of one side, thereby has improved the buffer effect of buffer layer to the bullet indirectly.

Preferably, the pressing block is spherical, and the pressing block can compress the buffer layers on the two sides by extruding the pressing plate when being pressed; the during operation, through the shape that sets up the briquetting, when the bullet beat in briquetting department, the bullet head can be to both sides motion under the guide effect of briquetting arcwall face this moment to can change the movement track of bullet, and make the bullet exert relative vertically effort to the buffer layer lateral wall after deflecting, thereby make the bullet can obtain more effective buffering, prevent that bullet head and glass board vertical action from leading to the condition that glass was penetrated easily.

Preferably, a hollow cavity is arranged inside the pressing block, a discharge hole is formed in one end, close to the adsorption cavity, of the pressing block, a blocking layer for sealing the inside of the hollow cavity is arranged inside the discharge hole, glue is filled inside the hollow cavity, and bayonet knives are connected to the side walls, corresponding to the discharge hole, of the buffer layer respectively; the during operation, when the bullet beat on the briquetting and drive the briquetting when moving to bayonet one side, the bayonet this moment can stab the shutoff layer and puncture, and make the glue of hollow intracavity portion flow, and fill in the cavity between buffer layer and glass board, glue can slow down the kinematic strength of bullet this moment, prevent the bullet from moving back and forth between two glass boards under the bounce-back of buffer layer, and lead to the fact the condition of damage to the glass board, glue can solidify gradually after meetting the air simultaneously, and bond and the shutoff by the mouth that the bullet punctures on the glass board, the intensity after the glass quilt bullet attack has been improved, also reduce dropping of glass piece simultaneously.

Preferably, a buffer groove is formed in one side, opposite to the discharge hole, of the pressing block, a rubber layer is installed inside the buffer groove, partition plates are arranged on the side walls, close to the buffer groove, of the hollow cavity, and a buffer block is filled in a sealed cavity formed by the partition plates and the side walls of the hollow cavity; when the glass bullet-proof impact buffering device works, when a bullet is hit to the buffering groove, the rubber layer and the buffering layer can play a certain buffering effect on the impact of the bullet in advance, and therefore the glass bullet-proof effect is further improved.

Preferably, one end of the hollow cavity, which is far away from the buffer groove, is provided with a guide block, and one end of the guide block, which is close to the partition plate, is symmetrically provided with inclined planes capable of forming included angles; during operation, when the bullet penetrates from the buffer slot and penetrates through the partition plate, the motion track of the bullet head can incline to one side under the guiding effect of the inclined plane, so that the buffer layer can play a more effective buffering effect on bullets with a relatively vertical effect, and the situation that the bulletproof glass is penetrated is further prevented.

Preferably, the inclined surfaces are respectively connected with a group of elastic buffer strips, and each group of buffer strips are connected through a rigid connecting rod; during operation, when the bullet was beaten under the effect of guide block on the buffering strip of one side, the buffering strip can take place buckling deformation under the effect of connecting rod this moment to play certain cushioning effect to the bullet, further reduced the damage of bullet to glass.

Preferably, air cavities are arranged in the buffer strips, air passages communicated with the air cavities are arranged in the connecting rods respectively, and pricking pins are arranged on the side walls of the hollow cavities corresponding to the ends, close to the discharge port, of the inclined surfaces respectively; the during operation, when the bullet drove the buffering strip and buckle when warping, the buffering strip that is close to the felting needle this moment can be punctured by the felting needle when warping for the inside air of air cavity is extruded and is promoted glue rapid solidification effect, prevents that the inside glue of hollow chamber is difficult to and solidifies slow condition with the air contact in the external world, has further improved the result of use of glue.

Preferably, a telescopic bag is arranged in the air cavity close to the partition plate, and the telescopic bag is in a compressed state under the action of air pressure of the air cavity; when the glue squeezing bag works, when the buffer strip close to the pricking pin is punctured, the air in the buffer strip can be squeezed out more fully when the telescopic bag expands under the action of the elasticity of the telescopic bag, and therefore the work of the glue can be promoted more effectively.

The process for preparing the laminated bulletproof glass is suitable for the bulletproof glass and comprises the following process steps:

s1: firstly, mounting a plugging plate on the end part of one glass plate through glue, so that the plugging plate and the glass plate form a mounting chamber;

s2: then wrapping the PVB layer on a metal mesh to form an integrated buffer layer, and placing the buffer layer in an installation chamber;

s3: and then, the pressing blocks are respectively placed at the concave parts on the exposed side of the buffer layer, the other glass plate is bonded with the end part of the plugging plate, and the middle part of the convex part on the exposed side of the buffer layer is bonded with the side wall of the glass plate, so that the required bulletproof glass is formed.

The invention has the following beneficial effects:

1. the bulletproof glass structure has the advantages that the buffer layer in the bulletproof glass structure can effectively buffer the impact force of bullets, the situation that the bullets penetrate through the glass is prevented, and meanwhile, when the glass plate facing to an attack position is broken, due to the fact that the glass plate is bonded with the PVB layer of the buffer layer in a toughness mode, fragments of the glass plate can be bonded with the PVB layer after the glass plate is damaged, so that the glass can keep certain integrity, the glass fragments are prevented from falling to cause personal injury or property loss, and the using effect of the bulletproof glass is further improved.

2. According to the invention, by setting the shape of the pressing block, the bullet head can move towards two sides under the guiding action of the arc-shaped surface of the pressing block, so that the movement track of the bullet can be changed, and the bullet exerts a relatively vertical acting force on the side wall of the buffer layer after deflecting, so that the bullet can be buffered more effectively, and the situation that the glass is easily penetrated due to the vertical action of the bullet head and the glass plate is prevented.

Drawings

The invention will be further explained with reference to the drawings.

FIG. 1 is a diagram of the process steps of the present invention;

FIG. 2 is a schematic structural view of the present invention;

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

FIG. 4 is a schematic view of the structure of a buffer strip according to the present invention;

in the figure: the device comprises a glass plate 1, a gap 2, a buffer layer 3, a metal net 4, a PVB layer 5, a pressing block 6, a pressing plate 7, a blocking plate 8, an adsorption cavity 9, a hollow cavity 10, a blocking layer 11, glue 12, a bayonet 13, a rubber layer 14, a partition plate 15, a buffer block 16, a guide block 17, an inclined plane 18, a buffer strip 19, a connecting rod 20, an air cavity 21, an air passage 22, a puncture needle 23 and a telescopic bag 24.

Detailed Description

In order to make the technical means, the creation features, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the following embodiments.

As shown in fig. 1-4, the laminated bulletproof glass of the present invention comprises a pair of glass plates 1 which are matched with each other; a gap 2 is arranged between the two glass plates 1, a wavy buffer layer 3 is arranged in the gap 2, the buffer layer 3 is composed of a metal net 4 and a PVB layer 5 wrapped on the outer surface of the metal net 4, the side wall of the buffer layer 3 is attached to the side walls of the glass plates 1 at two sides, the middle part of the convex part at one side of the buffer layer 3 is adhered to the side wall of the glass plate 1, rigid pressing blocks 6 are arranged at the concave parts corresponding to one side where the buffer layer 3 is adhered to the glass plate 1, pressing plates 7 are symmetrically connected to the side walls of the buffer layer 3 corresponding to the inner sides of the pressing blocks 6, the buffer layers 3 at two sides can be compressed through the pressing plates 7 when the pressing blocks 6 are pressed, and the end parts of the two glass plates 1 are connected through sealing plates 8; when the bulletproof glass works, the buffering effect of the bulletproof glass in the prior art on bullets is limited, so that the bulletproof glass still can be punctured or broken under the impact of strong bullets, and the use effect and the service life of the bulletproof glass are influenced; when the bulletproof glass is used, the glass plate 1 close to the pressing block 6 faces to one side which is easy to be attacked, when an external bullet penetrates through the layer of glass plate 1, if the attack position of the bullet falls on the convex part of the buffer layer 3 close to one side of the pressing block 6, the bullet can drive the buffer layer 3 which can elastically deform to compress towards two sides by extruding the position, so that the impact force of the bullet can be effectively buffered, the situation that the bullet penetrates through the glass is prevented, if the attack position of the bullet falls on the concave part of the buffer layer 3, the bullet can fall on the pressing block 6, the buffer layers 3 on two sides are driven by the pressing block 6 and the pressing plate 7 to respectively compress towards two sides, so that the bullet can also be effectively buffered, at the moment, the pressing block 6 matched with the buffer layer 3 is arranged, so that the bullet can be effectively buffered when falling on any position of the buffer layer 3, the bulletproof effect of the glass is greatly improved; meanwhile, when the glass plate 1 facing the attack part is broken, at the moment, due to the fact that the glass plate 1 is bonded with the PVB layer 5 in a toughness mode, fragments of the glass plate 1 can be bonded with the PVB layer 5 after the glass plate is damaged, the glass can keep certain integrity, personal injury or property loss caused by falling of the glass fragments can be prevented, and the using effect of the bulletproof glass is further improved.

As an embodiment of the invention, adsorption cavities 9 are respectively arranged at the positions of the side walls of the buffer layer 3 opposite to the pressing blocks 6, and the adsorption cavities 9 can be adsorbed on the glass plate 1 on one side; the during operation is through adsorbing absorption chamber 9 on the glass board 1 of one side for buffer layer 3 can drive absorption chamber 9 and slide relatively on glass board 1 when the atress warp, does not influence the effective work of buffer layer 3, and buffer layer 3 can constitute a plurality of relatively sealed cavities with this glass board 1 simultaneously, and the gas in the sealed cavity this moment can play certain support and reverse effect to the deformation of buffer layer 3 of one side, thereby has improved the buffering effect of buffer layer 3 to the bullet indirectly.

In one embodiment of the present invention, the compact 6 has a spherical shape, and the compact 6 can compress the buffer layers 3 on both sides by pressing the pressing plate 7 when being pressed; the during operation, through the shape that sets up briquetting 6, when the bullet beat at briquetting 6 departments, the bullet head can be to both sides motion under the guide effect of 6 arcwalls of briquetting this moment to can change the movement track of bullet, and make the bullet exert relative vertically effort to 3 lateral walls of buffer layer after deflecting, thereby make the bullet can obtain more effective buffering, prevent that bullet head and 1 vertical action of glass board from leading to the easy condition of being penetrated of glass.

As an embodiment of the invention, a hollow cavity 10 is arranged inside the pressing block 6, a discharge hole is arranged at one end of the pressing block 6 close to the adsorption cavity 9, a blocking layer 11 for sealing the inside of the hollow cavity 10 is arranged inside the discharge hole, glue 12 is filled inside the hollow cavity 10, and bayonet 13 is respectively connected to the side walls of the buffer layer 3 corresponding to the discharge hole; the during operation, when the bullet was beaten on briquetting 6 and drive briquetting 6 to bayonet 13 one side when moving, bayonet 13 can puncture blocking layer 11 this moment, and make the inside glue 12 of hollow chamber 10 flow, and fill in the cavity between buffer layer 3 and glass board 1, glue 12 can slow down the kinematic strength of bullet this moment, prevent that the bullet from moving back and forth between two glass boards 1 under buffer layer 3's bounce, and lead to the fact the condition of damage to glass board 1, glue 12 can solidify gradually after meetting the air simultaneously, and bond and the shutoff by the mouth that the bullet punctureed on the glass board 1, the intensity after the glass quilt bullet attack has been improved, also reduce dropping of glass piece simultaneously.

As an embodiment of the invention, a buffer groove is arranged on one side of the pressing block 6 opposite to the discharge port, a rubber layer 14 is arranged in the buffer groove, a partition 15 is arranged on the side wall of the hollow cavity 10 and the side wall close to the buffer groove, and a buffer block 16 is filled in a sealed cavity formed by the partition 15 and the side wall of the hollow cavity 10; when the glass bullet-proof device works, when a bullet hits the buffer groove, the rubber layer 14 and the buffer layer 3 can play a certain buffer effect on the impact of the bullet in advance, and therefore the glass bullet-proof effect is further improved.

As an embodiment of the invention, one end of the hollow cavity 10 far away from the buffer slot is provided with a guide block 17, and one end of the guide block 17 close to the partition 15 is symmetrically provided with inclined surfaces 18 capable of forming an included angle; when the bullet-proof glass is in work, when a bullet penetrates through the buffer slot and penetrates through the partition plate 15, the motion track of the bullet head can incline to one side under the guiding effect of the inclined surface 18, so that the buffer layer 3 can play a more effective buffering effect on the bullet with a relatively vertical effect, and the bullet-proof glass can be further prevented from being penetrated.

As an embodiment of the present invention, a set of elastic buffer strips 19 is respectively connected to the inclined surfaces 18, and each set of buffer strips 19 is connected to each other through a rigid connecting rod 20; when the bullet impact buffering device works, when a bullet impacts the buffering strip 19 on one side under the action of the guide block 17, the buffering strip 19 can be bent and deformed under the action of the connecting rod 20, a certain buffering effect is achieved on the bullet, and damage of the bullet to glass is further reduced.

As an embodiment of the invention, air cavities 21 are arranged inside the buffer strips 19, air passages 22 communicated with the air cavities 21 are respectively arranged inside the connecting rods 20, and pricking pins 23 are respectively arranged on the side walls of the hollow cavities 10 corresponding to one ends of the inclined surfaces 18 close to the discharge ports; when the bullet drives the buffer strip 19 to bend and deform, the buffer strip 19 close to the puncture needle 23 can be punctured by the puncture needle 23 when deforming, so that air in the air cavity 21 is extruded out, the rapid solidification effect of the glue 12 is promoted, the condition that the glue 12 in the hollow cavity 10 is difficult to contact with the outside air and is slowly solidified is prevented, and the using effect of the glue 12 is further improved.

As an embodiment of the present invention, a bellows 24 is disposed in the air cavity 21 near the partition 15, and the bellows 24 is in a compressed state under the action of the air pressure of the air cavity 21; in operation, when the buffer strip 19 close to the puncture needle 23 is punctured, the air inside the buffer strip 19 can be more sufficiently squeezed out when the bellows 24 expands under the action of its own elasticity, so that the work of the glue 12 can be more effectively promoted.

s1: firstly, mounting a plugging plate 8 at the end of one glass plate 1 by glue 12, so that the plugging plate 8 and the glass plate 1 form a mounting chamber;

s2: subsequently, the PVB layer 5 is wrapped on the metal mesh 4, so that an integrated buffer layer 3 is formed, and the buffer layer 3 is placed in the installation chamber;

s3: and then, pressing blocks 6 are respectively placed at the concave parts on the exposed side of the buffer layer 3, the other glass plate 1 is bonded with the end part of the plugging plate 8, and the middle part of the convex part on the exposed side of the buffer layer 3 is bonded with the side wall of the glass plate 1, so that the required bulletproof glass is formed.

When the glass plate is in operation, the glass plate 1 close to the pressing block 6 faces one side which is easy to be attacked, when an external bullet penetrates through the glass plate 1, if the attacking position of the bullet falls on the convex part of the buffer layer 3 close to one side of the pressing block 6, the bullet can drive the buffer layer 3 which can elastically deform to compress towards two sides by extruding the position, so that the impact force of the bullet can be effectively buffered, the situation that the bullet penetrates through the glass is prevented, if the attacking position of the bullet falls on the concave part of the buffer layer 3, the bullet can fall on the pressing block 6, the buffer layers 3 on two sides are driven by the pressing block 6 and the pressing plate 7 to respectively compress towards two sides, so that the effective buffering effect can be played to the bullet, at the moment, the pressing block 6 matched with the buffer layer 3 is arranged, so that the bullet can be effectively buffered when falling on any position of the buffer layer 3, the bulletproof effect of the glass is greatly improved; meanwhile, when the glass plate 1 facing the attack part is broken, at the moment, due to the fact that the glass plate 1 is bonded with the PVB layer 5 in a toughness mode, fragments of the glass plate 1 can be bonded with the PVB layer 5 after the glass plate is damaged, the glass can keep certain integrity, personal injury or property loss caused by falling of the glass fragments can be prevented, and the using effect of the bulletproof glass is further improved.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are given by way of illustration of the principles of the present invention, and that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A laminated bulletproof glass comprises a pair of glass plates (1) which are matched with each other; the method is characterized in that: a gap (2) is arranged between the two glass plates (1), a wave-shaped buffer layer (3) is arranged in the gap (2), the buffer layer (3) consists of a metal net (4) and a PVB layer (5) wrapped on the outer surface of the metal net (4), the side wall of the buffer layer (3) is attached to the side walls of the glass plates (1) at two sides, the middle part of the convex part at one side of the buffer layer (3) is adhered with the side wall of the glass plate (1), and rigid pressing blocks (6) are arranged at the concave parts corresponding to one side of the buffer layer (3) which is adhered to the glass plate (1), the side wall of the buffer layer (3) corresponding to the inner side of the pressing block (6) is symmetrically connected with a pressing plate (7), the pressing block (6) can compress the buffer layers (3) on two sides through the pressing plate (7) when being pressed, the ends of the two glass plates (1) are connected through a plugging plate (8); the side wall positions of the buffer layer (3) opposite to the pressing block (6) are respectively provided with an adsorption cavity (9), and the adsorption cavities (9) can be adsorbed on the glass plate (1) on one side; the pressing block (6) is spherical, and the pressing block (6) can compress the buffer layers (3) on the two sides through the extrusion pressing plate (7) when being pressed; a hollow cavity (10) is formed in the pressing block (6), a discharge hole is formed in one end, close to the adsorption cavity (9), of the pressing block (6), a sealing layer (11) for sealing the interior of the hollow cavity (10) is arranged in the discharge hole, glue (12) is filled in the hollow cavity (10), and bayonet knives (13) are connected to the side walls, corresponding to the discharge hole, of the buffer layer (3) respectively;

one side of the pressing block (6) opposite to the discharge hole is provided with a buffer groove, and a rubber layer (14) is arranged inside the buffer groove.