CN212949149U

CN212949149U - Novel thermal forming die of lunch box with cover

Info

Publication number: CN212949149U
Application number: CN202021533605.4U
Authority: CN
Inventors: 施少强
Original assignee: Guangdong Yuanxin Precision Mold Technology Co ltd
Current assignee: Guangdong Yuanxin Precision Mold Technology Co ltd
Priority date: 2020-07-29
Filing date: 2020-07-29
Publication date: 2021-04-13
Anticipated expiration: 2030-07-29

Abstract

A novel thermal forming die for a lunch box with a cover comprises an upper die and a lower die; the upper die comprises an upper die plate, an upper die body, an upper shear die and a pressing ring, the lower die comprises a lower die plate, a lower die body, a lower shear die, a box body forming die and a box cover forming die, a forming die partition wall is arranged in the lower shear die, and a pressing partition plate and a material baffle plate are arranged on the pressing ring, and the upper die is characterized in that: the lower end face of the pressing partition plate is provided with a connecting part forming pressing strip, and the upper end face of the forming die partition wall is provided with a strip-shaped connecting part forming groove; the bottom of the connecting part forming pressing strip is provided with an indentation strip, the bottom of the strip-shaped connecting part forming groove is provided with an indentation groove, and the indentation groove is matched with the indentation strip and corresponds to the indentation strip in position. The utility model discloses can form the crease of the intermediate position of "[" shape connecting portion and "[" shape connecting portion when shaping box body and lid, once only make the transversal novel area lid plastics lunch-box that personally submits of connecting portion [ "shape and the intermediate position of" [ "shape connecting portion has the crease.

Description

Novel thermal forming die of lunch box with cover

Technical Field

The utility model relates to a thermoforming equipment, concretely relates to novel thermoforming mould of area lid lunch-box.

Background

The plastic lunch box generally comprises a box body and a box cover, wherein one side edge of the box cover is integrally connected with one side edge of the box body, and the other side edge of the box body is provided with a jack for inserting an inserting piece arranged on the other side edge of the box cover.

The connecting portion between box body and the lid in traditional plastics lunch-box, its high position and box body open-top's border parallel and level, its thickness slightly is less than the thickness of box body, lid itself usually. When the box cover is required to be covered, the box cover is covered on the opening at the top of the box body after being overturned for a certain angle around the connecting part, and the inserting pieces are inserted into the inserting holes. After the box cover is covered on the plastic lunch box, the box cover has certain resilience force, and the box cover is fixed by inserting the inserting pieces into the inserting holes so as to prevent the box cover from being bounced open. However, limited by the strength of the inserting sheet, the inserting sheet is difficult to overcome the resilience force of the box cover in the using process, so that the inserting sheet is separated from the jack, and the box cover is opened again. Therefore, the applicant designs a novel plastic lunch box with a cover, the cross section of a connecting part between a box body and a box cover is in a [ -shape, two side edges of the [ -shaped connecting part are respectively connected with one side edge of the box body and one side edge of the box cover integrally, and a crease is arranged in the middle of the [ -shaped connecting part, so that when the box cover is covered on an opening at the top of the box body, the resilience force of the box cover can be greatly reduced due to the transition between the box cover and the box body through the [ -shaped connecting part.

Chinese utility model patent specification CN207432759U (the applicant's prior patent) discloses a thermoforming mold for a lunch box with a cover, comprising an upper mold and a lower mold; the upper die comprises an upper die plate, an upper die body, an upper shearing die, a punching device and a material pressing ring, wherein the upper die body is arranged on the upper die plate and is positioned below the upper die plate, the upper shearing die is arranged on the upper die body and is positioned below the upper die body, and the upper shearing die is provided with a cavity; the lower die comprises a lower die plate, a lower die body, a lower shear die, a box body forming die and a box cover forming die, the lower die body is arranged on the lower die plate and is positioned above the lower die plate, the lower shear die is arranged on the lower die body and is positioned above the lower die body, and the box body forming die and the box cover forming die are both arranged on the lower die body and are positioned on the inner side of the lower shear die; the punching device is positioned on one side of the box body forming die and comprises a punching cutter, a punching cutter rod and a punching cutter holder, the punching cutter holder is arranged on the upper die body, the upper end of the punching cutter rod is connected with the punching cutter holder, and the punching cutter is connected with the lower end of the punching cutter rod; the material pressing ring is arranged in a cavity of the upper shear die, the lower end face of the material pressing ring is matched with the upper end face of the lower shear die and corresponds to the upper end face of the lower shear die in position, a punching cutter bar guide hole and a punching cutter guide hole are formed in the side wall of the material pressing ring, the punching cutter bar guide hole and the punching cutter guide hole are both in the vertical direction, the punching cutter guide hole is located right below the punching cutter bar guide hole, the lower end of the punching cutter guide hole is opened on the lower end face of the material pressing ring, the upper end of the punching cutter guide hole is communicated with the lower end of the punching cutter bar guide hole, the punching cutter bar is located in the punching cutter bar guide hole, and. Usually, the inner edge of the lower end of the upper shear die is an upper shear blade, the outer edge of the upper end of the lower shear die is a lower shear blade, and the lower shear blade is matched with the upper shear blade. When the plastic lunch box is manufactured, firstly, the plastic sheet is heated to reach the molding temperature; the heated plastic sheet passes through a forming area, the thermal forming die is matched, and the plastic sheet is tightly attached to the box body forming die and the box cover forming die through positive pressure thermal forming or negative pressure thermal forming; the formed sheet material is sheared by the upper shearing blade and the lower shearing blade, the plastic lunch box is sheared from the formed sheet material to obtain a single plastic lunch box, and then the plastic lunch box is separated from the thermal forming die. And in the state of opening the die, the pressing ring descends, and the punching knife can be retracted into the punching knife guide hole. After the plastic sheet is formed and cooled by the thermoforming mold, when the lower shearing mold is matched with the upper shearing mold to shear the formed sheet after shaping, the punching cutter moves downwards relative to the lower shearing mold, the pressing ring and the lower shearing mold clamp the formed sheet together, and the relative position of the pressing ring and the lower shearing mold is kept unchanged, so that the punching cutter extends out of the lower end of the guiding hole of the punching cutter to punch a jack on the formed sheet. The cutting and the punching are carried out simultaneously, so that the single plastic lunch box with the insertion holes is obtained. However, such a thermoforming mold cannot form the "[" shaped connection part and the crease of the middle position of the "[" shaped connection part at the same time of molding the box body and the box cover, and thus needs to be improved.

Disclosure of Invention

The utility model aims to solve the technical problem that a novel take thermoforming mould of lid lunch-box is provided, this kind of thermoforming mould can form the crease of the intermediate position of "[" shape connecting portion and "[" shape connecting portion in the shaping box body and lid, once only make the transversal novel take lid plastics lunch-box that personally submits of connecting portion "[" shape and "[" shape connecting portion's intermediate position has the crease. The technical scheme is as follows:

a novel thermal forming die for a lunch box with a cover comprises an upper die and a lower die; the upper die comprises an upper die plate, an upper die body, an upper shear die and a material pressing ring, the upper die body is arranged on the upper die plate and is positioned below the upper die plate, the upper shear die is arranged on the upper die body and is positioned below the upper die body, the upper shear die is provided with a cavity, the inner edge of the lower end of the upper shear die is an upper shearing blade, the material pressing ring is arranged in the cavity of the upper shear die, and the lower end surface of the material pressing ring is matched with the upper end surface of the lower shear die and corresponds to the upper end surface of the lower; the lower die comprises a lower die plate, a lower die body, a lower shear die, a box body forming die and a box cover forming die, the lower die body is arranged on the lower die plate and is positioned above the lower die plate, the lower shear die is arranged on the lower die body and is positioned above the lower die body, the box body forming die and the box cover forming die are both arranged on the lower die body and are positioned at the inner side of the lower shear die, the outer edge of the upper end of the lower shear die is a lower shear blade, and the lower shear blade is matched with the upper shear blade; a forming die partition wall is arranged in the lower shear die and is positioned between the box body forming die and the box cover forming die; a pressing partition plate is arranged on the pressing ring, the pressing partition plate divides the cavity of the pressing ring into two parts, and the lower end surface of the pressing partition plate is matched with the upper end surface of the partition wall of the forming die and corresponds to the upper end surface of the partition wall of the forming die in position; the method is characterized in that: the lower end face of the pressing partition plate is provided with a connecting part forming pressing strip, the upper end face of the forming die partition wall is provided with a strip-shaped connecting part forming groove, and the strip-shaped connecting part forming groove is matched with the connecting part forming pressing strip and corresponds to the connecting part forming pressing strip in position; the bottom of the connecting part forming pressing strip is provided with an indentation strip, the bottom of the strip-shaped connecting part forming groove is provided with an indentation groove, and the indentation groove is matched with the indentation strip and corresponds to the indentation strip in position.

When the die is closed, the pressing ring presses the sheet material onto the lower shear die, the pressing partition plate presses the sheet material onto the partition wall of the forming die, and the part of the sheet material pressed by the pressing partition plate forms a connecting part between the box cover and the box body; the connecting part forming pressing strip presses the sheet of the connecting part in the strip-shaped connecting part forming groove, and the forming of the connecting part is completed by utilizing the combined action of the connecting part forming pressing strip and the inner surface of the strip-shaped connecting part forming groove (at the moment, the two convex parts and the connecting part forming pressing strip are positioned on the same straight line); the middle part of the sheet material of the connecting part is pressed to the indentation groove by the indentation strip to form a crease.

The cross section of the strip-shaped connecting part forming groove is generally in a [ -shape, and the cross section of the connecting part forming pressing strip is also generally in a [ -shape.

In a preferred scheme, the outlines of the openings at the two ends of the strip-shaped connecting part forming groove form a lower shearing blade at the end part of the connecting part; the lower end face of the upper shear die is provided with two protruding portions, the two protruding portions are located on two sides of the cavity of the upper shear die respectively, the two protruding portions correspond to the positions of two end portions of the connecting portion forming pressing strip respectively, the outline of the inner end of each protruding portion forms an upper shear blade at the end portion of the connecting portion, and the upper shear blade at the end portion of the connecting portion is matched with the lower shear blade at the end portion of the connecting portion and corresponds to the positions of the. The outlines of the openings at the two ends of the strip-shaped connecting part forming groove are both in a [ -shape, and the outlines of the inner ends (namely, the ends close to the upper shear die cavity) of the two convex parts are both in a [ -shape. After the forming is finished, the lower shearing blade on the outer edge of the upper end of the lower shearing die is matched with the upper shearing blade on the inner edge of the lower end of the upper shearing die, the formed sheet after the shaping is sheared, the plastic lunch box is sheared from the formed sheet, and the single plastic lunch box with the box cover is obtained. The lower shearing blades of the two connecting part end parts are matched with the upper shearing blades of the two connecting part end parts respectively, and the connecting parts between the two connecting part end parts and the formed sheet are cut off, so that the two connecting part end parts are ensured to be smooth.

The connecting portion end portion lower shearing blade forms a part of the lower shearing blade, and the connecting portion end portion upper shearing blade forms a part of the upper shearing blade. Among the lower shearing cutting edge, box body part lower shearing cutting edge, lid part lower shearing cutting edge all roughly are the U-shaped, and box body part lower shearing cutting edge one end is connected box lid portion lower shearing cutting edge one end through a connecting portion tip lower shearing cutting edge, and box body part lower shearing cutting edge other end is connected the box lid portion lower shearing cutting edge other end through another connecting portion tip lower shearing cutting edge to constitute annular lower shearing cutting edge. In the upper shearing blade, the upper shearing blade of the box body part and the upper shearing blade of the box cover part are both in a U shape, one end of the upper shearing blade of the box body part is connected with the upper shearing blade of the box cover part through the upper shearing blade of a connecting part end part to shear one end of the upper shearing blade of the box body part, and the other end of the upper shearing blade of the box body part is connected with the upper shearing blade of the box cover part through the upper shearing blade of the other connecting part end part to shear the.

Generally, the connecting portion forming bead, the strip-shaped connecting portion forming groove, the indentation strip and the indentation groove are all linear, and the connecting portion forming bead, the strip-shaped connecting portion forming groove, the indentation strip and the indentation groove have the same direction. Preferably, the connecting part forming pressing strips are symmetrical about the indentation strips, and the strip-shaped connecting part forming grooves are symmetrical about the indentation grooves.

In a preferred embodiment, the upper mold further comprises a punching device; the punching device is positioned on one side of the box body forming die and comprises a punching cutter, a punching cutter rod and a punching cutter holder, the punching cutter holder is arranged on the upper die body, the upper end of the punching cutter rod is connected with the punching cutter holder, and the punching cutter is connected with the lower end of the punching cutter rod; the side wall of the pressing ring is provided with a punching cutter bar guide hole and a punching cutter guide hole, the punching cutter bar guide hole and the punching cutter guide hole are in the vertical direction, the punching cutter guide hole is positioned right below the punching cutter bar guide hole, the lower end of the punching cutter guide hole is opened on the lower end face of the pressing ring, the upper end of the punching cutter guide hole is communicated with the lower end of the punching cutter bar guide hole, the punching cutter bar is positioned in the punching cutter bar guide hole, and the punching cutter is positioned in the punching cutter guide hole. And in the state of opening the die, the pressing ring descends, and the punching knife can be retracted into the punching knife guide hole. After the plastic sheet is formed and cooled by the thermoforming mold, when the lower shearing mold is matched with the upper shearing mold to shear the formed sheet after shaping, the punching cutter moves downwards relative to the lower shearing mold, the pressing ring and the lower shearing mold clamp the formed sheet together, and the relative position of the pressing ring and the lower shearing mold is kept unchanged, so that the punching cutter extends out of the lower end of the guiding hole of the punching cutter to punch a jack on the formed sheet. The cutting and the punching are carried out simultaneously, so that the single plastic lunch box with the insertion holes is obtained.

In a more preferred scheme, the punching device further comprises a punching knife buffer cushion, an adjusting nut seat and a pressure adjusting screw rod, the adjusting nut seat is fixedly installed on the upper die body, a screw hole moving up and down is formed in the adjusting nut seat, the pressure adjusting screw rod is meshed with the screw hole of the adjusting nut seat, the punching knife seat is located right below the pressure adjusting screw rod, the punching knife buffer cushion is arranged between the lower end of the pressure adjusting screw rod and the punching knife seat, the lower end of the pressure adjusting screw rod is in close contact with the top of the punching knife buffer cushion, and the bottom of the punching knife buffer cushion is in close contact with the punching knife seat. Through rotating the pressure adjusting screw, the height position of the pressure adjusting screw can be adjusted, so that the degree of compression of the cushion pad of the punching knife is adjusted, and the punching pressure of the punching knife can be adjusted. The punch knife cushion may be made of an elastic material, preferably a polyurethane elastomer. In a more preferable scheme, the top of the cushion pad of the punching knife is provided with a gasket made of stainless steel or aluminum alloy, the lower end of the pressure adjusting screw is in close contact with the gasket, and the gasket is in close contact with the top of the cushion pad of the punching knife.

The material pressing ring can move up and down in the cavity of the upper shearing die, and the material pressing ring presses the sheet material onto the lower shearing die during die assembly. In a specific scheme, a compression spring is arranged between the pressing ring and the upper template, and the pressing ring can apply certain pressure to the plastic sheet to be molded when the compression spring contracts. In another specific scheme, a sealing ring is arranged outside the material pressing ring, so that a pressure air chamber (provided with a compressed air channel communicated with the pressure air chamber) is formed between the upper end of the material pressing ring and the inner wall of the cavity of the upper shear die, and compressed air can be introduced into the pressure air chamber, so that the material pressing ring can apply certain pressure on the plastic sheet to be formed. In another specific scheme, a compression spring is arranged between the material pressing ring and the upper die plate, a sealing ring is arranged on the outer side of the material pressing ring, a pressure air chamber is formed between the upper end of the material pressing ring and the inner wall of the cavity of the upper shear die (a compressed air channel communicated with the pressure air chamber is arranged on the upper die), and the material pressing ring applies a certain pressure to the plastic sheet to be molded by adopting the combination of the compression spring and compressed air.

In a preferred scheme, the upper die further comprises a stretching mechanism, and the stretching mechanism comprises a box body stretching head, a box body stretching rod, a box cover stretching head, a box cover stretching rod, a stretching rod mounting plate and a stretching rod mounting plate lifting control mechanism; the box body stretching head and the box cover stretching head are arranged in a cavity of the material pressing ring, the box body stretching head is located right above a box body forming die, the box cover stretching head is located right above a box cover forming die, the lower end of a box body stretching rod is connected with the box body stretching head, the lower end of a box cover stretching rod is connected with the box cover stretching head, the upper end of the box body stretching rod and the upper end of the box cover stretching rod extend out of the upper portion of the upper template and are connected with stretching rod mounting plates, and the stretching rod mounting plates are connected. The lifting control mechanism of the stretching rod mounting plate can be arranged on the upper template; the lifting control mechanism of the stretching rod mounting plate can also be arranged on the frame under the condition that the upper die is fixed on the frame. The lifting control mechanism of the stretching rod mounting plate is used for driving the stretching rod mounting plate to move up and down, and the box body stretching rod and the box cover stretching rod drive the box body stretching head and the box cover stretching head to simultaneously move up and down in the cavity of the material pressing ring. When the stretching rod mounting plate lifting control mechanism drives the stretching rod mounting plate to lift, the stretching rod mounting plate, the box body stretching rod, the box cover stretching rod, the box body stretching head and the box cover stretching head lift together, and when the box body stretching head and the box cover stretching head descend, the sheet to be formed is pre-stretched. The stretching rod mounting plate lifting control mechanism can comprise a stretching cylinder, and the stretching rod mounting plate is connected with a piston rod of the stretching cylinder; the cylinder body of the stretching cylinder can be arranged on the upper template; the cylinder body of the stretching cylinder can also be arranged on the frame under the condition that the upper die is fixed on the frame.

In a preferred scheme, the box body forming die comprises a box body side die and a box body movable bottom die, the box body side die is installed on the lower die body and is positioned on the inner side of the lower shearing die, and the box body movable bottom die is arranged on the inner side of the box body side die; the box cover forming die comprises a box cover side die, a first box cover movable die capable of lifting relative to the box cover side die and a second box cover movable die capable of lifting relative to the box cover side die and the first box cover movable die, the box cover side die is fixedly arranged on the lower die body and is positioned on the inner side of the lower shear die, the first box cover movable die is arranged on the inner side of the box cover side die, and the second box cover movable die is arranged on the inner side of the first box cover movable die; the lower die also comprises a box body ejector rod, a box cover ejector rod, an ejector rod mounting plate, an inner top plate and an inner top plate lifting cylinder; the ejection rod mounting plate is arranged below the lower template, the upper end of the box body ejection rod is connected with the box body movable bottom die, the upper end of the box cover ejection rod is connected with the second box cover movable die, and the lower end of the box body ejection rod and the lower end of the box cover ejection rod both extend out of the lower template and are connected with the ejection rod mounting plate; an inner top plate accommodating cavity is formed in the lower die body, the inner top plate is arranged in the inner top plate accommodating cavity, the lower end of the first box cover movable die is connected with the inner top plate, a cylinder body of an inner top plate lifting cylinder is fixedly installed on the lower die plate, and a piston rod of the inner top plate lifting cylinder faces upwards and is connected with the inner top plate. When the box body forming die is positioned at a position required by forming, the box body side die and the box body movable bottom die jointly form a box body forming die corresponding to the box body of the plastic lunch box; when the box cover forming die is located at a position required by forming, the box cover side die, the first box cover movable die and the second box cover movable die jointly form the box cover forming die corresponding to the box cover of the plastic lunch box. The lifting of the first box cover movable die is controlled by a lifting mechanism, namely an inner top plate lifting cylinder, the lifting of the second box cover movable die and the box body movable bottom die is controlled by another lifting mechanism (namely a mechanism for driving the ejector rod mounting plate to lift), and secondary demolding (wherein secondary demolding of the box cover and primary demolding of the box body) can be realized by setting the stroke of the two lifting mechanisms: in the first-stage demolding process, the first box cover movable die, the second box cover movable die and the box body movable bottom die synchronously ascend, so that the edge of the box cover is separated from the side die; in the second-stage demolding process, the second box cover movable mold and the box body movable bottom mold continue to ascend, and the plastic lunch box is ejected out.

In a more preferable scheme, the lower template is provided with a tube positive guide pillar which runs up and down, the upper end of the tube positive guide pillar is connected with the lower template, the ejector rod mounting plate is provided with a tube positive guide sleeve, and the tube positive guide pillar is positioned in the tube positive guide sleeve. When the ejector rod mounting plate goes up and down relative to the lower template, the positive guide sleeve of the tube slides along the positive guide pillar of the tube, so that the ejector rod mounting plate, the box body ejector rod and the box cover ejector rod can be guided to go up and down more stably.

In a more preferred scheme, the lower template is provided with a limiting shaft moving up and down, the ejector rod mounting plate is provided with a limiting through hole, the limiting shaft is located in the limiting through hole, the lower end of the limiting shaft is sleeved with a lower limiting washer, and the lower limiting washer is located below the ejector rod mounting plate. When the lower surface of the ejector rod mounting plate contacts with the upper end surface of the lower limiting washer in the descending process of the ejector rod mounting plate, the ejector rod mounting plate does not descend any more.

In another preferred scheme, the box body forming die comprises a box body side die and a box body movable bottom die, the box body side die is installed on the lower die body and is positioned on the inner side of the lower shear die, and the box body movable bottom die is arranged on the inner side of the box body side die; the box cover forming die comprises a box cover side die and a box cover movable bottom die, the box cover side die is arranged on the lower die body and is positioned on the inner side of the lower shear die, and the box cover movable bottom die is arranged on the inner side of the box body side die; the lower die further comprises a box body ejection rod, a box cover ejection rod and an ejection rod mounting plate, the ejection rod mounting plate is arranged below the lower die plate, the upper end of the box body ejection rod is connected with a box body movable bottom die, the upper end of the box cover ejection rod is connected with the box cover movable bottom die, and the lower end of the box body ejection rod and the lower end of the box cover ejection rod extend out of the lower die plate and are connected with the ejection rod mounting plate. When the box body forming die is positioned at a position required by forming, the box body side die and the box body movable bottom die jointly form a box body forming die corresponding to the box body of the plastic lunch box; when the box cover forming die is located at a position required by forming, the box cover side die and the box cover movable bottom die jointly form the box cover forming die corresponding to the box cover of the plastic lunch box. The lifting of the box body movable bottom die and the box cover movable bottom die is controlled by a mechanism for driving the ejector rod mounting plate to lift, and after the forming and shearing of the box body and the box cover are completed, the ejector rod mounting plate rises to drive the box body movable bottom die and the box cover movable bottom die to rise together to eject the plastic lunch box.

The shape and size of the edge of the punching knife are designed according to the shape and size of a hole to be punched (the lower end of the punching knife is the edge), and the punching knife is generally a straight edge.

During molding, the upper die can be fixed on the frame, and the lower die can be lifted relative to the upper die; the lower die can also be fixed on the frame, and the upper die can be lifted relative to the lower die.

The utility model discloses can form the crease of the intermediate position of "[" shape connecting portion and "[" shape connecting portion when shaping box body and lid, once only make the transversal novel area lid plastics lunch-box that personally submits of connecting portion [ "shape and the intermediate position of" [ "shape connecting portion has the crease.

Drawings

Fig. 1 is a schematic structural view of a preferred embodiment of the present invention (in a state where the die is not drawn after the die assembly);

FIG. 2 is an enlarged view of portion A of FIG. 1;

FIG. 3 is a perspective view of a lower shear die in a preferred embodiment of the present invention;

FIG. 4 is an enlarged view of portion B of FIG. 3;

FIG. 5 is a perspective view of an upper shear die in a preferred embodiment of the present invention;

fig. 6 is a perspective view of a swaging ring in a preferred embodiment of the present invention;

fig. 7 is a schematic structural view of the novel plastic lunch box with a cover.

Detailed Description

As shown in fig. 1 and 2, the thermoforming mold for the novel lunch box with the cover comprises an upper mold 1 and a lower mold 2.

The lower die 2 comprises a lower die plate 21, a lower die body 22, a lower shear die 23, a box body forming die 24 and a box cover forming die 25, wherein the lower die body 22 is arranged on the lower die plate 21 and is positioned above the lower die plate 21, the lower shear die 23 is arranged on the lower die body 22 and is positioned above the lower die body 22, and the box body forming die 24 and the box cover forming die 25 are arranged on the lower die body 22 and are positioned on the inner side of the lower shear die 23.

In this embodiment, the box forming mold 24 includes a box side mold 241 and a box movable bottom mold 242, the box side mold 241 is installed on the lower mold body 22 and located inside the lower shear mold 23, and the box movable bottom mold 242 is located inside the box side mold 241; the box cover forming die 25 comprises a box cover side die 251, a first box cover movable die 252 capable of lifting relative to the box cover side die 251, and a second box cover movable die 253 capable of lifting relative to the box cover side die 251 and the first box cover movable die 252, wherein the box cover side die 251 is fixedly arranged on the lower die body 22 and is positioned at the inner side of the lower shear die 23, the first box cover movable die 252 is arranged at the inner side of the box cover side die 251, and the second box cover movable die 253 is arranged at the inner side of the first box cover movable die 252; the lower die 2 further comprises a box body ejection rod 26, a box cover ejection rod 27, an ejection rod mounting plate 28, an inner top plate 29 and an inner top plate lifting cylinder 210; the ejector rod mounting plate 28 is arranged below the lower template 21, the upper end of the box body ejector rod 26 is connected with the box body movable bottom die 242, the upper end of the box cover ejector rod 27 is connected with the second box cover movable die 253, and the lower end of the box body ejector rod 26 and the lower end of the box cover ejector rod 27 extend out of the lower template 21 and are connected with the ejector rod mounting plate 28; an inner top plate accommodating cavity 211 is formed in the lower die body 22, an inner top plate 29 is arranged in the inner top plate accommodating cavity 211, the lower end of the first box cover movable die 252 is connected with the inner top plate 29, a cylinder body 2101 of an inner top plate lifting cylinder 210 is fixedly installed on the lower die plate 21, and a piston rod 2102 of the inner top plate lifting cylinder 210 faces upwards and is connected with the inner top plate 29. When the box forming die 24 is located at a position required for forming, the box side die 241 and the box movable bottom die 242 jointly form a box forming die corresponding to the box of the plastic lunch box; when the box cover forming die 25 is located at a position required for forming, the box cover side die 251, the first box cover movable die 252 and the second box cover movable die 253 together form a box cover forming die corresponding to the box cover of the plastic lunch box. The lower template 2 is provided with a tube positive guide post 212 which runs up and down, the upper end of the tube positive guide post 212 is connected with the lower template 21, the ejector rod mounting plate 28 is provided with a tube positive guide sleeve 213, and the tube positive guide post 212 is positioned in the tube positive guide sleeve 213; when the ejector rod mounting plate 28 is lifted relative to the lower template, the tube guide 213 slides along the tube guide post 212, so that the ejector rod mounting plate 28, the box body ejector rod 26 and the box cover ejector rod 27 can be guided to lift more stably. The lower template 21 is provided with a vertically-oriented limiting shaft 214, the ejector rod mounting plate 28 is provided with a limiting through hole 215, the limiting shaft 214 is positioned in the limiting through hole 215, the lower end of the limiting shaft 214 is sleeved with a lower limiting washer 216, and the lower limiting washer 216 is positioned below the ejector rod mounting plate 28; during the lowering of the ejector rod mounting plate 28, when the lower surface of the ejector rod mounting plate 28 contacts the upper end surface of the lower limit washer 214, the ejector rod mounting plate 28 is no longer lowered.

The upper die 1 comprises an upper die plate 11, an upper die body 12, an upper shear die 13, a punching device 14 and a material pressing ring 15. An upper die body 12 is mounted on the upper die plate 11 and located below the upper die plate 11, an upper shear die 13 is mounted on the upper die body 12 and located below the upper die body 12, and the upper shear die 13 has a cavity.

The punching device 14 is positioned at one side of the box body forming die 24, the punching device 14 comprises a punching knife 141, a punching knife bar 142, a punching knife seat 143, a punching knife buffer pad 144, an adjusting nut seat 145 and a pressure adjusting screw 146, the upper end of the punching knife bar 142 is connected with the punching knife seat 143, the punching knife 141 is connected with the lower end of the punching knife bar 142, the adjusting nut seat 145 is fixedly arranged on the upper die body 12, the adjusting nut seat 145 is provided with a screw hole which runs up and down, the pressure adjusting screw 146 is meshed with the screw hole of the adjusting nut seat 145, the punching knife seat 143 is positioned right below the pressure adjusting screw 146, the punching knife buffer pad 144 is arranged between the lower end of the pressure adjusting screw 146 and the punching knife seat 143, the top of the punching knife buffer pad 144 is provided with a gasket 147 made of stainless steel or aluminum alloy, the lower end of the pressure adjusting screw 146 is, the bottom of the punch blade cushion 144 is in close contact with the punch blade seat 143 (the punch blade seat 143 is mounted on the upper die body by the punch blade cushion 144, the spacer 147, the adjusting nut seat 145 and the pressure adjusting screw 146). The punch knife bumper 144 is made of a polyurethane elastomer.

The pressing ring 15 is arranged in a cavity of the upper shear die 13, the lower end face of the pressing ring 15 is matched with and corresponds to the upper end face of the lower shear die 23, a punching cutter bar guide hole 151 and a punching cutter guide hole 152 are arranged on the side wall of the pressing ring 15, the punching cutter bar guide hole 151 and the punching cutter guide hole 152 are both in the vertical direction, the punching cutter guide hole 152 is positioned right below the punching cutter bar guide hole 151, the lower end of the punching cutter guide hole 152 is opened on the lower end face of the pressing ring 15, the upper end of the punching cutter guide hole 152 is communicated with the lower end of the punching cutter bar guide hole 151, the punching cutter bar 142 is positioned in the punching cutter bar guide hole 151, and the punching cutter 141 is positioned in the punching cutter guide hole 152.

The present embodiment uses a combination of a compression spring and compressed gas to cause the swage ring to apply a certain pressure to the plastic sheet to be formed. In this embodiment, the top of the swaging ring 15 is provided with two lower guiding sections 154, and the tops of the two lower guiding sections 154 are respectively provided with an upper guiding section 155; two lower guide holes 111 which run up and down are arranged on the upper die body 11, the two lower guide sections 154 correspond to the two lower guide holes 111 one by one, and the lower guide sections 154 are positioned in the lower guide holes 111 and are in sliding fit with the inner walls of the lower guide holes 111; a sealing ring 112 is arranged on the outer side of the lower guide section 154, so that a pressure air chamber 113 is formed between the top of the lower guide section 154 and the upper die body 12 and the upper die plate 11, and the pressure air chamber 113 is communicated with a compressed gas channel 114 arranged on the upper die plate 11; the upper template 11 is provided with two upper guide holes 115 which run up and down, the two upper guide sections 155 correspond to the two upper guide holes 115 one by one, and the upper guide sections 155 are positioned in the upper guide holes 115 and are in sliding fit with the inner walls of the upper guide holes 115; the top of the upper guide section 155 is provided with an external thread section 156, and the external thread section 156 is provided with the adjusting nut 116; the upper guide section 155 is sleeved with a compression spring 117, the upper end of the compression spring 117 is in close contact with the upper template 11, and the lower end of the compression spring is in close contact with the top of the lower guide section 154. The pressure of the press ring can be adjusted by adjusting the pressure of the compressed gas entering the pressure chamber 113. When the upper die 1 and the lower die 2 are separated, under the combined action of gravity and the compression spring 117, the lower end of the material pressing ring 15 extends out of the upper shear die 13; the length of the lower end extension of the press ring 15 can be adjusted by adjusting the mounting position of the adjusting nut 116 on the external thread section 156. The two upper guide sections 155 are respectively provided with a vertically-running stretching rod guide hole 157, the box body stretching rod 17 is positioned in one stretching rod guide hole 157 and is in sliding fit with the inner wall of the stretching rod guide hole 157, and the box cover stretching rod 19 is positioned in the other stretching rod guide hole 157 and is in sliding fit with the inner wall of the stretching rod guide hole 157.

The shape and size of the edge of the punch 141 are designed according to the shape and size of the hole to be punched (the lower end of the punch is the edge), such as a straight edge.

In this embodiment, the upper mold 1 further includes a stretching mechanism, and the stretching mechanism includes a box body stretching head 16, a box body stretching rod 17, a box cover stretching head 18, a box cover stretching rod 19, a stretching rod mounting plate 110, and a stretching rod mounting plate lifting control mechanism; the box body stretching head 16 and the box cover stretching head 18 are both arranged in a cavity of the material pressing ring 15, the box body stretching head 16 is positioned right above a box body forming die 24, the box cover stretching head 18 is positioned right above a box cover forming die 25, the lower end of the box body stretching rod 17 is connected with the box body stretching head 16, the lower end of the box cover stretching rod 19 is connected with the box cover stretching head 18, the upper end of the box body stretching rod 17 and the upper end of the box cover stretching rod 19 both extend out of the upper die plate 11 and are connected with a stretching rod mounting plate 110, and the stretching rod mounting plate 110 is connected with a. The lifting control mechanism of the stretching rod mounting plate can be arranged on the upper template; the lifting control mechanism of the stretching rod mounting plate can also be arranged on the frame under the condition that the upper die is fixed on the frame. The lifting control mechanism of the stretching rod mounting plate is used for driving the stretching rod mounting plate 110 to move up and down, and drives the box body stretching head 16 and the box cover stretching head 18 to move up and down in the cavity of the material pressing ring 15 through the box body stretching rod 17 and the box cover stretching rod 19. When the stretching rod mounting plate lifting control mechanism drives the stretching rod mounting plate 110 to lift, the stretching rod mounting plate 110, the box body stretching rod 17, the box cover stretching rod 19, the box body stretching head 16 and the box cover stretching head 18 lift together, and when the box body stretching head 16 and the box cover stretching head 18 descend, the sheet to be formed is stretched in advance. The stretching rod mounting plate lifting control mechanism can comprise a stretching cylinder, and the stretching rod mounting plate is connected with a piston rod of the stretching cylinder; the cylinder body of the stretching cylinder can be arranged on the upper template; the cylinder body of the stretching cylinder can also be arranged on the frame under the condition that the upper die is fixed on the frame.

In this embodiment, the lower shear die 23 is provided with a forming die partition wall 217, and the forming die partition wall 217 is located between the box body forming die 24 and the box cover forming die 25; the pressing ring 15 is provided with a pressing partition plate 153, the pressing partition plate 153 divides the cavity of the pressing ring 15 into two parts, and the lower end surface of the pressing partition plate 153 is matched with the upper end surface of the forming die partition wall 217 and corresponds in position.

Referring to fig. 2 to 6, the inner edge of the lower end of the upper shear block 13 is an upper shear blade 131, and the outer edge of the upper end of the lower shear block 23 is a lower shear blade 231, and the lower shear blade 231 matches the upper shear blade 131. A connecting part forming pressing strip 118 is arranged on the lower end face of the material pressing partition plate 153, a strip-shaped connecting part forming groove 218 is arranged on the upper end face of the forming die partition wall 217, and the strip-shaped connecting part forming groove 218 is matched with the connecting part forming pressing strip 118 and corresponds to the connecting part forming pressing strip 118 in position; the profile of the openings at both ends of the bar-shaped connecting portion forming groove 218 constitutes a connecting portion end portion lower shearing blade 2311; two protrusions 119 are arranged on the lower end face of the upper shear die 13, the two protrusions 119 are located on two sides of the cavity of the upper shear die 13 respectively, the two protrusions 119 correspond to two end portions of the connecting portion molding bead 118 respectively, the inner end profile of the protrusions 119 forms an upper shearing blade 1311 of the connecting portion end, and the upper shearing blade 1311 of the connecting portion end is matched with a lower shearing blade 2311 of the connecting portion end and corresponds to the connecting portion end. The opening outlines at the two ends of the strip-shaped connecting part forming groove 218 are both in a [ -shape, and the outlines of the inner ends (namely, the ends close to the upper shear die cavity) of the two protruding parts 119 are both in a [ -shape; the cross-sectional shape of the bar-shaped connecting portion forming groove 218 is "[", and the cross-sectional shape of the connecting portion forming bead 118 is also "[".

The connection end lower shearing blade 2311 constitutes a part of the lower shearing blade 231, and the connection end upper shearing blade 1311 constitutes a part of the upper shearing blade 131. Referring to fig. 3, in the lower cutting blade 231, the case body portion lower cutting blade 2312 and the lid portion lower cutting blade 2313 are substantially U-shaped, one end of the case body portion lower cutting blade 2312 is connected to one end of the lid portion lower cutting blade 2313 by a connecting portion end lower cutting blade 2311, and the other end of the case body portion lower cutting blade 2312 is connected to the other end of the lid portion lower cutting blade 2313 by another connecting portion end lower cutting blade 2311, thereby constituting the annular lower cutting blade 231. Referring to fig. 5, the upper cutting blade 131 is formed such that the body portion upper cutting blade 1312 and the lid portion upper cutting blade 1313 are substantially U-shaped, one end of the body portion upper cutting blade 1312 is connected to one end of the lid portion upper cutting blade 1313 by a connecting portion end upper cutting blade 1311, and the other end of the body portion upper cutting blade 1312 is connected to the other end of the lid portion upper cutting blade 1313 by another connecting portion end upper cutting blade 1311, thereby forming the annular upper cutting blade 131.

Referring to fig. 2, in the present embodiment, the bottom of the connecting portion forming bead 118 is provided with an indentation strip 120, and the bottom of the strip-shaped connecting portion forming groove 218 is provided with an indentation groove 219, and the indentation groove 219 is matched with and corresponds to the indentation strip 120. Referring to fig. 3 and 6, the connection part molding bead 118, the bar-shaped connection part molding groove 218, the indentation strip 120, and the indentation groove 219 are all linear, and the connection part molding bead 118, the bar-shaped connection part molding groove 218, the indentation strip 120, and the indentation groove 219 are in the same orientation. The connector-forming bead 118 is symmetrical about the indentation strip 120 and the strip-shaped connector-forming groove 218 is symmetrical about the indentation groove 219.

In addition, in order to shorten the molding cycle, an internal mold circulation cooling water path is usually provided to cool the molding mold and rapidly cool and shape the product.

The working principle of the thermoforming mold is briefly described as follows:

during molding, the upper die 1 is fixed on the frame, and the lower die 2 is lifted relative to the upper die 1.

Before production, the height position of the pressure adjusting screw 146 is adjusted by rotating the pressure adjusting screw 146 so as to adjust the degree of compression of the cushion pad 144 of the punching knife, and the punching pressure of the punching knife 141 is adjusted.

When the plastic lunch box is manufactured, firstly, the plastic sheet is heated to reach the molding temperature; when the heated plastic sheet passes through the forming area, the lower die 2 rises, the thermoforming die is closed, the compression spring 117 and compressed gas entering the pressure gas chamber 113 jointly apply downward thrust to the pressing ring 15, so that the pressing ring 15 presses the sheet on the upper end surface of the lower shear die 23, meanwhile, the pressing partition board 153 presses the sheet on the forming die partition wall 217, the connecting part forming pressing strip 118 presses the sheet of the connecting part in the strip-shaped connecting part forming groove 218, the forming of the connecting part is completed by the combined action of the connecting part forming pressing strip 118 and the inner surface of the strip-shaped connecting part forming groove 218 (at this time, the two convex parts 119 and the connecting part forming pressing strip 118 are on the same straight line), the indentation groove 219 is matched with the indentation strip 120 to press creases on the connecting part, and a forming gas chamber is formed between the plastic sheet and the cavity of the upper shear die 13; then introducing compressed air into the forming air chamber, and under the action of the compressed air, tightly attaching the plastic sheet to the box body forming die 24 and the box cover forming die 25; then, cooling water is introduced into a circulating cooling water path in the die, and the box body forming die 24 and the box cover forming die 25 are cooled to shape the formed sheet; then the lower die 2 is further lifted, the punching knife 141 moves downwards relative to the lower shear die 23, the material pressing ring 15 and the lower shear die 23 clamp the formed sheet material together, the punching knife 141 extends out from the lower end of the punching knife guide hole 152 to punch a jack on the formed sheet material, meanwhile, a lower shearing blade on the outer edge of the upper end of the lower shear die 23 is matched with an upper shearing blade on the inner edge of the lower end of the upper shear die 13 to shear the formed sheet material after shaping, and the plastic lunch box is sheared from the formed sheet material (at the moment, the lower shearing blades 2311 on the end parts of the two connecting parts are respectively matched with the upper shearing blades 1311 on the end parts of the two connecting parts, and the connecting part between the two end parts of the connecting parts and the formed sheet material is cut off), so that the; then the lower die 2 descends, the edge of the plastic lunch box leaves the material pressing ring 15 (in the state of opening the die, the material pressing ring 15 descends, and the punching knife 141 retracts into the punching knife guide hole 152); subsequently, the inner top plate lifting cylinder 210 drives the first box cover movable die 252 to lift relative to the lower template 21 through the inner top plate 29, and the ejector rod mounting plate 28 drives the box body ejector rod 26, the box body movable bottom die 242, the box cover ejector rod 27 and the second box cover movable die 253 to lift relative to the lower template 21, so as to eject the plastic lunch box, so that the plastic lunch box is separated from the thermal forming die, thereby completing the one-time thermal forming process. Next, the lower mold 2 is raised, and the box body movable bottom mold 242, the first cover movable mold 252 and the second cover movable mold 253 are returned to the positions required for the next thermal forming process.

As shown in fig. 7, the novel plastic lunch box with the cover comprises a box body 01 and a box cover 02, wherein one side edge of the box cover 02 is integrally connected with one side edge of the box body 01 through a connecting part 03, the other side edge of the box body 01 is provided with a jack, and the jack is used for inserting an insertion sheet 04 arranged on the other side edge of the box cover 02. The cross section of the connecting part 03 between the box body 01 and the box cover 02 is in a [ -shape, two side edges of the [ -shaped connecting part 03 are respectively connected with one side edge of the box body 01 and one side edge of the box cover 02 into a whole, and a crease 05 is arranged in the middle of the [ -shaped connecting part 03.

In other embodiments, the box forming mold comprises a box side mold and a box movable bottom mold, the box side mold is mounted on the lower mold body and is positioned at the inner side of the lower shear mold, and the box movable bottom mold is arranged at the inner side of the box side mold; the box cover forming die comprises a box cover side die and a box cover movable bottom die, the box cover side die is arranged on the lower die body and is positioned on the inner side of the lower shear die, and the box cover movable bottom die is arranged on the inner side of the box body side die; the lower die further comprises a box body ejection rod, a box cover ejection rod and an ejection rod mounting plate, the ejection rod mounting plate is arranged below the lower die plate, the upper end of the box body ejection rod is connected with a box body movable bottom die, the upper end of the box cover ejection rod is connected with the box cover movable bottom die, and the lower end of the box body ejection rod and the lower end of the box cover ejection rod extend out of the lower die plate and are connected with the ejection rod mounting plate. When the box body forming die is positioned at a position required by forming, the box body side die and the box body movable bottom die jointly form a box body forming die corresponding to the box body of the plastic lunch box; when the box cover forming die is located at a position required by forming, the box cover side die and the box cover movable bottom die jointly form the box cover forming die corresponding to the box cover of the plastic lunch box. The lifting of the box body movable bottom die and the box cover movable bottom die is controlled by a mechanism for driving the ejector rod mounting plate to lift, and after the forming and shearing of the box body and the box cover are completed, the ejector rod mounting plate rises to drive the box body movable bottom die and the box cover movable bottom die to rise together to eject the plastic lunch box.

Claims

1. A novel thermal forming die for a lunch box with a cover comprises an upper die and a lower die; the upper die comprises an upper die plate, an upper die body, an upper shear die and a material pressing ring, the upper die body is arranged on the upper die plate and is positioned below the upper die plate, the upper shear die is arranged on the upper die body and is positioned below the upper die body, the upper shear die is provided with a cavity, the inner edge of the lower end of the upper shear die is an upper shearing blade, the material pressing ring is arranged in the cavity of the upper shear die, and the lower end surface of the material pressing ring is matched with the upper end surface of the lower shear die and corresponds to the upper end surface of the lower; the lower die comprises a lower die plate, a lower die body, a lower shear die, a box body forming die and a box cover forming die, the lower die body is arranged on the lower die plate and is positioned above the lower die plate, the lower shear die is arranged on the lower die body and is positioned above the lower die body, the box body forming die and the box cover forming die are both arranged on the lower die body and are positioned at the inner side of the lower shear die, the outer edge of the upper end of the lower shear die is a lower shear blade, and the lower shear blade is matched with the upper shear blade; a forming die partition wall is arranged in the lower shear die and is positioned between the box body forming die and the box cover forming die; a pressing partition plate is arranged on the pressing ring, the pressing partition plate divides the cavity of the pressing ring into two parts, and the lower end surface of the pressing partition plate is matched with the upper end surface of the partition wall of the forming die and corresponds to the upper end surface of the partition wall of the forming die in position; the method is characterized in that: the lower end face of the pressing partition plate is provided with a connecting part forming pressing strip, the upper end face of the forming die partition wall is provided with a strip-shaped connecting part forming groove, and the strip-shaped connecting part forming groove is matched with the connecting part forming pressing strip and corresponds to the connecting part forming pressing strip in position; the bottom of the connecting part forming pressing strip is provided with an indentation strip, the bottom of the strip-shaped connecting part forming groove is provided with an indentation groove, and the indentation groove is matched with the indentation strip and corresponds to the indentation strip in position.

2. The thermoforming mold of the new lunch box with cover as claimed in claim 1, wherein: the connecting part forming pressing strip, the strip-shaped connecting part forming groove, the indentation strip and the indentation groove are all linear, and the connecting part forming pressing strip, the strip-shaped connecting part forming groove, the indentation strip and the indentation groove are consistent in trend.

3. The thermoforming mold of the new lunch box with cover as claimed in claim 1, wherein: the outlines of the openings at the two ends of the strip-shaped connecting part forming groove form a lower shearing blade at the end part of the connecting part; the lower end face of the upper shear die is provided with two protruding portions, the two protruding portions are located on two sides of the cavity of the upper shear die respectively, the two protruding portions correspond to the positions of two end portions of the connecting portion forming pressing strip respectively, the outline of the inner end of each protruding portion forms an upper shear blade at the end portion of the connecting portion, and the upper shear blade at the end portion of the connecting portion is matched with the lower shear blade at the end portion of the connecting portion and corresponds to the positions of the.

4. The thermoforming mold of the new lunch box with cover as claimed in claim 3, wherein: in the lower shearing blades, the lower shearing blade of the box body part and the lower shearing blade of the box cover part are both in a U shape, one end of the lower shearing blade of the box body part is connected with one end of the lower shearing blade of the box cover part through the lower shearing blade at the end part of a connecting part, and the other end of the lower shearing blade of the box body part is connected with the other end of the lower shearing blade of the box cover part through the lower shearing blade at the end part of the other; in the upper shearing blade, the upper shearing blade of the box body part and the upper shearing blade of the box cover part are both in a U shape, one end of the upper shearing blade of the box body part is connected with the upper shearing blade of the box cover part through the upper shearing blade of one connecting part end part to shear one end of the blade, and the other end of the upper shearing blade of the box body part is connected with the upper shearing blade of the box cover part through the upper shearing blade of the other connecting part end part to.

5. The thermoforming mold of the new lunch box with cover as claimed in claim 3, wherein: the cross section of the strip-shaped connecting part forming groove is in a [ -shape, and the cross section of the connecting part forming pressing strip is also in a [ -shape; the outlines of openings at two ends of the strip-shaped connecting part forming groove are both in a [ -shape, and the outlines of the inner ends of the two protruding parts are both in a [ -shape.

6. The new thermoforming mold for lunch boxes with lids as claimed in any one of claims 1 to 5, wherein: the upper die also comprises a punching device; the punching device is positioned on one side of the box body forming die and comprises a punching cutter, a punching cutter rod and a punching cutter holder, the punching cutter holder is arranged on the upper die body, the upper end of the punching cutter rod is connected with the punching cutter holder, and the punching cutter is connected with the lower end of the punching cutter rod; the side wall of the pressing ring is provided with a punching cutter bar guide hole and a punching cutter guide hole, the punching cutter bar guide hole and the punching cutter guide hole are in the vertical direction, the punching cutter guide hole is positioned right below the punching cutter bar guide hole, the lower end of the punching cutter guide hole is opened on the lower end face of the pressing ring, the upper end of the punching cutter guide hole is communicated with the lower end of the punching cutter bar guide hole, the punching cutter bar is positioned in the punching cutter bar guide hole, and the punching cutter is positioned in the punching cutter guide hole.

7. The thermoforming mold of the new lunch box with cover as claimed in claim 6, wherein: the punching device further comprises a punching knife buffer cushion, an adjusting nut seat and a pressure adjusting screw rod, the adjusting nut seat is fixedly installed on the upper die body, a screw hole with an upper trend and a lower trend is formed in the adjusting nut seat, the pressure adjusting screw rod is meshed with the screw hole of the adjusting nut seat, the punching knife seat is located right below the pressure adjusting screw rod, the punching knife buffer cushion is arranged between the lower end of the pressure adjusting screw rod and the punching knife seat, the lower end of the pressure adjusting screw rod is in close contact with the top of the punching knife buffer cushion, and the bottom of the punching knife buffer cushion is in close contact with the punching.

8. The new thermoforming mold for lunch boxes with lids as claimed in any one of claims 1 to 5, wherein: the upper die further comprises a stretching mechanism, and the stretching mechanism comprises a box body stretching head, a box body stretching rod, a box cover stretching head, a box cover stretching rod, a stretching rod mounting plate and a stretching rod mounting plate lifting control mechanism; the box body stretching head and the box cover stretching head are arranged in a cavity of the material pressing ring, the box body stretching head is located right above a box body forming die, the box cover stretching head is located right above a box cover forming die, the lower end of a box body stretching rod is connected with the box body stretching head, the lower end of a box cover stretching rod is connected with the box cover stretching head, the upper end of the box body stretching rod and the upper end of the box cover stretching rod extend out of the upper portion of the upper template and are connected with stretching rod mounting plates, and the stretching rod mounting plates are connected.

9. The new thermoforming mold for lunch boxes with lids as claimed in any one of claims 1 to 5, wherein: the box body forming die comprises a box body side die and a box body movable bottom die, the box body side die is installed on the lower die body and is positioned on the inner side of the lower shearing die, and the box body movable bottom die is arranged on the inner side of the box body side die; the box cover forming die comprises a box cover side die, a first box cover movable die capable of lifting relative to the box cover side die and a second box cover movable die capable of lifting relative to the box cover side die and the first box cover movable die, the box cover side die is fixedly arranged on the lower die body and is positioned on the inner side of the lower shear die, the first box cover movable die is arranged on the inner side of the box cover side die, and the second box cover movable die is arranged on the inner side of the first box cover movable die; the lower die also comprises a box body ejector rod, a box cover ejector rod, an ejector rod mounting plate, an inner top plate and an inner top plate lifting cylinder; the ejection rod mounting plate is arranged below the lower template, the upper end of the box body ejection rod is connected with the box body movable bottom die, the upper end of the box cover ejection rod is connected with the second box cover movable die, and the lower end of the box body ejection rod and the lower end of the box cover ejection rod both extend out of the lower template and are connected with the ejection rod mounting plate; an inner top plate accommodating cavity is formed in the lower die body, the inner top plate is arranged in the inner top plate accommodating cavity, the lower end of the first box cover movable die is connected with the inner top plate, a cylinder body of an inner top plate lifting cylinder is fixedly installed on the lower die plate, and a piston rod of the inner top plate lifting cylinder faces upwards and is connected with the inner top plate.

10. The new thermoforming mold for lunch boxes with lids as claimed in any one of claims 1 to 5, wherein: the box body forming die comprises a box body side die and a box body movable bottom die, the box body side die is installed on the lower die body and is positioned on the inner side of the lower shearing die, and the box body movable bottom die is arranged on the inner side of the box body side die; the box cover forming die comprises a box cover side die and a box cover movable bottom die, the box cover side die is arranged on the lower die body and is positioned on the inner side of the lower shear die, and the box cover movable bottom die is arranged on the inner side of the box body side die; the lower die further comprises a box body ejection rod, a box cover ejection rod and an ejection rod mounting plate, the ejection rod mounting plate is arranged below the lower die plate, the upper end of the box body ejection rod is connected with a box body movable bottom die, the upper end of the box cover ejection rod is connected with the box cover movable bottom die, and the lower end of the box body ejection rod and the lower end of the box cover ejection rod extend out of the lower die plate and are connected with the ejection rod mounting plate.