Method and apparatus for trimming flat cut plant fiber molded articles

Abstract

This invention relates to an automatic trimming method and device for molded articles made from plant fibers including pulp (hereinafter referred to as plant fibers). The aim is to provide a trimming method and device that, after trimming, completely separates the product from the waste edge without any lingering threads, ensures the waste edge no longer surrounds the product but is positioned below it, and guarantees that the product is not lifted after trimming but remains in a fixed position. The technical solution is a trimming method for flat-cut plant fiber molded articles, characterized by: an ejector plate that can move vertically relative to the upper mold body is provided on the upper trimming mold; an ejector spring is installed between the ejector plate and the upper trimming mold; a positioning block that positions the product and a positioning block spring that presses against the positioning block are provided on the lower trimming mold. The positioning block can move vertically relative to the lower mold body to achieve complete separation of the product from the trimmed waste edge after trimming.

Description

Technical Field

[0001] This invention relates to an automatic edge trimming method and device for molded articles made of plant fibers including pulp (hereinafter referred to as plant fibers); in particular, an automatic method for removing and cutting excess edges of molded articles made of plant fibers, an automatic method for separating individual articles in integral articles (hereinafter collectively referred to as edge trimming), and a corresponding edge trimming device. Background Technology

[0002] Existing plant fiber molding production equipment often produces molded plant fiber products with burrs and uneven edges, failing to meet design requirements. For example, the outer edge of the same product may vary, with some areas larger than the designed edge and others smaller, or the edges may have small burrs. To achieve a precise product shape or contour, the current method involves leaving a certain amount of trimming allowance on the product before trimming, and then removing the excess portion to obtain the desired shape or required product. We categorize the removal of excess portions, the slitting of individual components in a continuous product, piercing the product, and leaving cuts or indentations on the product as trimming of plant fiber molded products. Edges cut from usable parts are called waste edges.

[0003] Currently, there is a significant problem with edge trimming of plant fiber molded products both domestically and internationally: after trimming, a few fibers remain tangled, preventing complete separation between the product and the waste edge. Although this does not affect the appearance and the fibers break easily, the product is still accompanied by the stuck waste edge when it is removed, making automatic separation of the product and waste edge impossible and greatly impacting efficiency. Even if the fibers are completely cut off, the waste edge remains around the product, causing it to be removed along with the product after automatic trimming, affecting product quality and yield.

[0004] In addition, another significant problem exists when automatically trimming plant fiber molded products. After trimming, when the trimming mold opens and moves upward, the trimmed product often gets stuck in the trimming mold or is lifted up by the moving mold and then falls back down, deviating from its original position. This causes subsequent products to be stuck or unable to be automatically removed, affecting the positioning of later products. This necessitates frequent machine stops for repairs, making automatic trimming impossible. Solving these problems is extremely difficult.

[0005] To solve these edge trimming problems, the following must be done: 1. Design an edge trimming device to separate the waste edge from the product after it has been trimmed; 2. When removing the trimmed product from the trimming mold, the waste edge should ideally be located below the product; 3. The trimmed product should be accurately positioned before trimming and must be in a fixed position after trimming; 4. In order not to affect the production speed, the above requirements must be completed during the trimming process. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a cutting method and device that, after cutting, completely separates the product from the waste edge without any tangling, prevents the waste edge from wrapping around the product and instead places it below the product, and ensures that the product is not lifted up after cutting but remains in a fixed position. This cutting method and device should be stable in operation and simple in structure to improve product quality and production efficiency.

[0007] The technical solution provided by this invention is:

[0008] A method for trimming the edges of molded plant fiber products with a flat cut is characterized by: an unloading plate that can move up and down relative to the upper mold body is provided on the upper mold for trimming the edges, and an unloading spring is installed between the unloading plate and the upper mold for trimming the edges; a positioning block that can position the product and a positioning block spring that presses against the positioning block are provided on the lower mold for trimming the edges, and the positioning block can move up and down relative to the lower mold body to achieve complete separation of the product and the cut-off waste edge after trimming.

[0009] The lower end face of the unloading plate is lower than the outer side of the lower end face of the upper mold body;

[0010] The lower mold body includes: a lower mold top edge plate located around each positioning block, a top edge plate spring that applies force vertically upward to the lower mold top edge plate, and a blade mold fixed with the cutting edge facing upward between the positioning block and the lower mold top edge plate for cutting edges. The positioning block is positioned vertically and vertically within the blade mold, and the lower mold top edge plate is positioned vertically and vertically around the blade mold so that the cut waste edge and the cut edge product are pushed onto the blade mold by the upward movement of the lower mold top edge plate and the upward movement of the positioning block, respectively.

[0011] The outer side of the upper end face of the positioning block is higher than the top edge plate of the lower mold;

[0012] The trimming process for plant fiber molded products is carried out according to the following steps:

[0013] The upper die with the stripper plate moves down. The lower end face of the stripper plate first contacts the waste edge of the product to be cut, which is placed on the lower die of the lower die. The waste edge of the product to be cut is pressed onto the top edge plate of the lower die of the lower die. The upper die continues to move down. The lower end face of the upper die first presses onto the product and the positioning block and pushes the positioning block down. Then the lower end face of the upper die presses onto the top edge plate of the lower die. The upper die pushes the positioning block and the top edge plate of the lower die together down. The top edge plate spring and the positioning block spring are compressed. The stripper plate pressed on the top edge plate of the lower die also moves down together with the top edge plate of the lower die and the upper die until the upper die presses the edge of the product to be cut onto the blade die and cuts off the waste edge.

[0014] After the trimming is completed, the trimming upper mold moves upward with the upper mold body, the top edge plate spring and the positioning block spring return, and the lower mold top edge plate and positioning block move upward with the upper mold body. The upward movement of the lower mold top edge plate and the upward movement of the positioning block push the trimmed waste edge and the trimmed product above the blade mold, respectively. The upper limit position of the positioning block is slightly higher than the upper limit position of the lower mold top edge plate. The lower mold top edge plate moves upward to its position first, and then the positioning block moves upward to its position, so that the trimmed product stays at a position higher than the trimmed waste edge. The trimming upper mold continues to move upward with the upper mold body. The upper mold body disengages from the positioning block carrying the trimmed product, and the stripper plate continues to press the trimmed waste edge for a short time under the action of the stripper spring, until the limit rod pulls the stripper plate upward and leaves the trimmed waste edge.

[0015] A flat-cut plant fiber molded product trimming device is characterized in that: the trimming device includes: an upper trimming mold and a lower trimming mold; a stripper plate that can move up and down relative to the upper mold body is provided on the upper trimming mold, and a stripper spring is installed between the stripper plate and the upper trimming mold; a plurality of positioning blocks that can position the product are provided on the lower trimming mold, and a positioning block spring is installed between the positioning blocks and the lower mounting plate so that the positioning blocks can move up and down relative to the lower mold body, thereby achieving complete separation of the product and the cut-off waste edge after trimming;

[0016] The lower end face of the unloading plate is lower than the outer side of the lower end face of the upper mold body;

[0017] The lower mold body includes: a lower mold top edge plate located around each positioning block, a top edge plate spring that applies force vertically upward to the lower mold top edge plate, and a blade mold fixed with the cutting edge facing upward between the positioning block and the lower mold top edge plate for cutting edges; the positioning block is positioned vertically and vertically within the blade mold, and the lower mold top edge plate is positioned vertically and vertically around the blade mold, so that the cut waste edge and the cut edge product are pushed onto the blade mold by the upward movement of the mold top edge plate and the upward movement of the positioning block, respectively;

[0018] The outer side of the upper end face of the positioning block is higher than the top edge plate of the lower mold;

[0019] The lower end face of the upper mold body can press against the top edge plate of the lower mold and push the positioning block and the top edge plate of the lower mold together to move downward.

[0020] The beneficial effects of this invention are: during the trimming process, the waste edge is completely separated from the product and the waste edge is kept in the lower trimming mold. At the same time, the product is positioned above and the waste edge is positioned below the product. When the product is automatically removed, it will not stick to the waste edge, ensuring that the product is not lifted after trimming and remains in a fixed position. This realizes the automation of trimming, product removal and waste edge removal, and improves product quality and production efficiency. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the main structure of a cutting device for plant fiber molded products.

[0022] Figure 2 yes Figure 1 The diagram shows a cross-sectional view of the trimming device for plant fiber molded products along the AA direction.

[0023] Figure 3 This is a schematic diagram of the mold closing state of the upper and lower trimming molds (the product is trimmed, and the stripper plate 1a presses the waste edge 3.2 onto the lower trimming mold, and the waste edge and the product have been cut off).

[0024] Figure 4 yes Figure 3 A magnified schematic diagram of a local structure.

[0025] Figure 5 This is a cross-sectional structural diagram of a plant fiber molded product edge trimming device that uses a blade flat cutting method for edge trimming (the blade is bent into the shape of the product and fixed in the lower mold for edge trimming).

[0026] Figure 6 This is a cross-sectional view of a plant fiber molded product trimming device that uses a blade flat cutting method for trimming (the diagram shows the state when the upper and lower trimming molds are closed and the blade is about to cut into the product to be cut).

[0027] Figure 7 yes Figure 6 A magnified schematic diagram of a local structure.

[0028] Figure 8 This is a schematic diagram of the edge-cutting device for plant fiber molded products installed on an edge-cutting machine.

[0029] Explanation of the numbers in the diagram: 1-Upper cutting mold; 1.1-Upper mold body; 1.2-Upper mold mounting plate; 1.3-Ejector spring; 1.4-Ejector plate guide post; 1.5-Limiting rod; 1a-Ejector plate; 1b-Elastic body; 2-Lower cutting mold; 2.1-Lower mold body; 2.1.1-Lower mold top plate; 2.1.2-Blade fixing plate; 2.1.3-Top plate spring; 2.1.4-Blade mold; 2.1.5-Pressure plate; 2.1.6-Top plate limiting guide rod; 2.2-Positioning block; 2.3-Positioning block spring; 2.4-Lower mounting plate; 2.5-Positioning block guide post; 3-Product to be cut; 3.1-Product after cutting; 3.2-Scrap edge. Detailed Implementation

[0030] The following description, in conjunction with the embodiments shown in the accompanying drawings, provides further details.

[0031] The method provided by this invention involves setting a stripper plate 1a on the upper mold 1 for edge trimming, which can move vertically relative to the upper mold body 1.1. During the trimming process, the stripper plate 1a first presses down on the waste edges around each upper mold body 1.1. As the upper mold body 1.1 continues to move downward, it pushes the positioning block 2.2 downward until the waste edges are cut off from the product. When the upper mold 1 for edge trimming opens and moves upward, the stripper plate 1a continues to press down on the waste edges until the positioning block lifts the trimmed product and moves it upward until the edge of the trimmed product is slightly higher than the upper limit of the waste edges. Only after the upper mold body 1.1 disengages from the positioning block does the stripper plate 1a begin to move upward away from the cut waste edges. This process completely separates the trimmed product from the cut waste edges and leaves the waste edges in the lower mold 2 for edge trimming, conveniently placing the trimmed product on top of the cut waste edges. This creates conditions for the next step of removing the trimmed product and waste edges separately.

[0032] There are many methods for cutting the fibers between the finished product and the waste edge, two typical methods are: 1. Punching method, also known as shearing method, such as... Figure 3 , Figure 4 As shown, during edge trimming, the upper mold body 1.1 is inserted into the lower mold body 2.1, like scissors, to cut the waste edge off the product; 2. Blade flat cutting method, such as... Figure 6 , Figure 7 As shown.

[0033] Example 1, punching method

[0034] like Figure 1 , Figure 2 , Figure 3 The plant fiber molded product trimming device shown includes: an upper trimming mold 1, a lower trimming mold 2, a stripper plate 1a, and a sponge. The upper trimming mold 1 includes: an upper mold body 1.1 and an upper mold mounting plate 1.2.

[0035] The stripper plate 1a is mounted on the cutting edge mold 1 via the stripper plate guide post 1.4, the limit rod 1.5, and the stripper spring 1.3.

[0036] Edge trimming devices using the punching method, such as Figure 2 , Figure 3 As shown, during edge trimming, the upper mold body 1.1 of the upper trimming mold 1 is inserted into the lower mold body 2.1 of the lower trimming mold 2. The upper mold body 1.1 and the lower mold body 2.1 shear each other, cutting the waste edge off the product. Figure 4 As shown, the outer side of the lower end face of the upper mold body 1.1 and the inner side of the upper end face of the lower mold body 2.1 cooperate to form a shear. The outer side of the lower end face of the upper mold body 1.1 can be regarded as the upper cutting edge, and the inner side of the upper end face of the lower mold body 2.1 can be regarded as the lower cutting edge.

[0037] like Figure 1 , Figure 2 , Figure 8As shown, the upper cutting mold 1 is located directly above the lower cutting mold 2. The stripper plate 1a is installed on the upper cutting mold 1 via the stripper plate guide post 1.4 and the limiting rod 1.5, and the upper mold body 1.1 passes through the stripper plate 1a. In other words, the stripper plate 1a is fitted around the upper mold body 1.1. The stripper plate 1a can slide up and down on the stripper plate guide post 1.4, that is, the stripper plate can move up and down relative to the upper mold body 1.1 along the stripper plate guide post 1.4. The limiting rod 1.5 acts as a lower limit for the stripper plate 1a, restricting the lowest position of the stripper plate 1a relative to the upper mold body 1.1 (the bottom end of the limiting rod passes through the through hole of the upper mold mounting plate and is fixedly connected to the stripper plate by threads; the nut head at the top of the limiting rod is hooked at the top opening of the through hole because its diameter is larger than the through hole). A stripper spring 1.3 is also installed between the stripper plate and the upper mold of the cutting edge. The stripper spring 1.3, which is pre-compressed and has a certain elasticity, is compressed between the stripper plate 1a and the upper mold mounting plate 1.2 of the upper mold of the cutting edge mold 1. Under the action of the elasticity of the stripper spring 1.3 and its own weight, the stripper plate 1a has a downward tendency, but the limiting rod 1.5 pulls the stripper plate 1a to prevent the stripper plate 1a from popping out of the upper mold of the cutting edge mold 1. The limiting rod 1.5 plays a limiting role on the stripper plate 1a, restricting the stripper plate 1a to a minimum limit position relative to the upper mold body 1.1.

[0038] The lower die 2 for trimming includes: a lower die body 2.1, a positioning block 2.2, a positioning block spring 2.3, a lower mounting plate 2.4, and a positioning block guide post 2.5.

[0039] The overall or partial shape of the positioning block 2.2 matches the overall or partial shape of the product, so that the product to be cut 3 is accurately positioned on the lower cutting mold. During the cutting process, the product to be cut is first fed into the positioning block 2.2 of the lower cutting mold 2, and the product to be cut is accurately positioned on the positioning block 2.2 of the lower cutting mold, waiting for the cutting.

[0040] Several positioning blocks 2.2 are mounted on the lower mounting plate 2.4 via positioning block guide posts 2.5. The positioning blocks 2.2 are installed inside the lower mold body 2.1, or in other words, the lower mold body 2.1 is fitted around the positioning blocks 2.2. Each positioning block may have one or more positioning block guide posts 2.5. The positioning blocks 2.2 can slide up and down along the positioning block guide posts 2.5, so the positioning blocks can move up and down relative to the lower mold body 2.1, the lower mounting plate 2.4, and other parts of the trimming lower mold 2. A positioning block spring 2.3 is provided between the positioning block and the lower mounting plate 2.4 of the trimming lower mold. The positioning block spring 2.3, which is pre-compressed and has a certain elastic force, lifts the positioning blocks 2.2. The positioning block guide post 2.5 also serves a limiting function, preventing the positioning block spring 2.3 from ejecting the positioning block 2.2 from the lower die 2 and limiting the positioning block 2.2 to its highest position relative to the lower die body 2.1 (the bottom end of the positioning block guide post passes through the through hole of the positioning block and is then fixed to the lower mounting plate by screws; the top boss of the positioning block guide post, because its diameter is larger than the through hole, hooks onto the top opening of the through hole, preventing the positioning block from detaching from the positioning block guide post). The highest position that the positioning block 2.2 can reach is its upper limit position. Alternatively, the lower die body 2.1 can directly guide the positioning block 2.2 installed inside the lower die body 2.1, while the positioning block guide post 2.5 only serves a limiting function for the positioning block 2.2. Alternatively, the positioning block guide post 2.5 can only serve a guiding function for the positioning block 2.2, while a separate limiting rod serves as the upper limit for the positioning block 2.2.

[0041] During the trimming process, the product to be trimmed is fed onto the positioning block 2.2 of the lower trimming mold 2 to await trimming. The positioning block 2.2 accurately positions the product to be trimmed on the lower trimming mold. The upper trimming mold 1 with the stripper plate 1a moves downward. The lower end face of the stripper plate 1a is slightly lower than the lower end face of the upper mold body 1.1, so the lower end face of the stripper plate 1a first contacts the waste edge of the product to be trimmed placed on the lower trimming mold 2, and presses the waste edge of the product to be trimmed onto the lower trimming mold 2. In this embodiment, the waste edge of the product to be trimmed is pressed onto the lower mold body 2.1 of the lower trimming mold 2. The upper mold body 1.1 of the upper trimming mold 1 continues to move downward, pressing against the positioning block 2.2 with the product. The upper mold body 1.1 pushes the positioning block 2.2 with the product downward and cuts off the waste edge. The upper mold body 1.1 then stops moving downward.

[0042] After the trimming is completed, the upper trimming mold 1 moves upward along with the upper mold body 1.1. At this time, the positioning block 2.2, carrying the trimmed product, also begins to move upward with the upper mold body 1.1 under the action of the positioning block spring 2.3. The stripper plate 1a continues to press the trimmed waste edge onto the lower trimming mold 2 under the elastic force of the stripper spring 1.3 until the positioning block lifts the trimmed product and moves it to the upper limit position, and the upper mold body 1.1 disengages from the positioning block, and the stripper plate 1a slides to the lowest limit position of the limit rod 1.5. Only then does the stripper plate 1a move upward with the upper trimming mold and leave the trimmed waste edge. That is, the stripper plate 1a moves upward with the upper trimming mold and leaves the trimmed waste edge only when the following conditions are met: the positioning block lifts the trimmed product and moves it to the upper limit position, the upper mold body 1.1 disengages from the positioning block, and the stripper plate 1a slides to the lowest limit position of the limit rod 1.5.

[0043] This process completely separates the trimmed product from the cut-off waste edge, and allows the waste edge to remain in the lower mold 2, conveniently placing the trimmed product on top of the cut-off waste edge. This creates conditions for the next step of removing the trimmed product and the waste edge separately.

[0044] The upper cutting mold 1 moves up to position with the unloading plate 1a. The cut products and the cut waste edges, which are no longer stuck together, are removed from the lower cutting mold 2 in distinct layers and placed separately. The new products to be cut are then sent to the positioning block 2.2 of the lower cutting mold 2 to wait for cutting.

[0045] In practice, the following problems may occur: After the upper die 1 moves down to complete the trimming, when the upper die 1 moves up, the trimmed product is often caught in the mold and moves upwards, or the trimmed product caught in the mold falls down and deviates from the positioning block. That is, after trimming, the trimmed product often does not remain on the positioning block 2.2 of the lower die 2, but is sucked onto the upper die 1.1, stuck on the upper die 1.1, or falls off the positioning block 2.2 after moving upwards. The consequence is that subsequent products will be continuously stuck on the upper die 1.1, or products that fall off the positioning block 2.2 after moving upwards cannot be automatically removed, thus hindering the positioning of the next batch of products to be cut. In this case, the trimming cannot proceed normally and the machine must be stopped.

[0046] After repeated experiments, we found that installing an elastomer 1b (such as a sponge or rubber block) on the upper mold 1 after trimming can completely solve the problem of the product being sucked or stuck on the upper mold 1.1 after trimming.

[0047] like Figure 2 , Figure 3 As shown, each edge of the mold 1 has a sponge installed in the upper mold body 1.1. When the mold is closed and the edge is cut, the sponge can press against the product on its corresponding positioning block 2.2.

[0048] Each upper mold body 1.1 contains a sponge, meaning a sponge is placed above each positioning block 2.2. Each set of sponges can be installed on the upper mold body 1.1 of the trimming upper mold 1, or on the upper mold mounting plate 1.2 of the trimming upper mold 1. However, there must be one or a set of sponges above each positioning block 2.2 to ensure that each product remains on the positioning block 2.2 when the mold is opened after trimming, thus eliminating the "stuck" phenomenon where the product gets stuck on the upper mold body 1.1 or is pulled up by the upper mold body 1.1 after trimming.

[0049] Because of its elasticity, during the process of the upper cutting mold 1 moving down and closing with the lower cutting mold 2 to cut off the waste edge, the sponge presses down on the positioning block 2.2 of the lower cutting mold 2 before the upper mold body 1.1 reaches it, holding the product to be cut on the positioning block 2.2. After the waste edge is cut off, the upper cutting mold 1 moves upward with the upper mold body 1.1. During the rebound and expansion process, the sponge can also press the cut product onto the positioning block 2.2 of the lower cutting mold 2. After the upper mold body 1.1 detaches from the positioning block 2.2, the sponge can still press the product to be cut on the positioning block 2.2 for a short time due to its rebound and expansion. The upper cutting mold 1 continues to move upward with the upper mold body 1.1, and the sponge completes its rebound, ensuring that the cut product remains on the positioning block 2.2. Then, the sponge moves upward with the upper mold body 1.1 and leaves the cut product. Other elastomers can also be used, but because of the sponge's softness, it will not damage the surface of the product, so the sponge is preferred here.

[0050] The sponge effectively prevents the trimmed product from being caught and leaving the positioning block 2.2 of the lower trimming mold 2 when the upper trimming mold 1 moves upward after opening. This ensures that the trimmed product remains on the positioning block 2.2 of the lower trimming mold 2 when the upper trimming mold 1 moves upward after opening, eliminating the jamming phenomenon of the upper mold body 1.1 on the trimmed product.

[0051] Example 2, Blade flat cutting method

[0052] like Figure 5 , Figure 6 , Figure 7As shown, the lower mold body 2.1 of the blade flat cutting method edge cutting mold 2 is a combined structure. The lower mold body 2.1 includes a lower mold top edge plate 2.1.1, a blade fixing plate 2.1.2, a top edge plate spring 2.1.3, a blade mold 2.1.4, a pressure plate 2.1.5, and a top edge plate limiting guide rod 2.1.6. The blade mold 2.1.4, which is formed by bending the blade, replaces the lower cutting edge of the lower mold body 2.1 described in Example 1. The blade is bent to form a closed blade mold 2.1.4 with the same shape as the edge of the product to be cut. The blade is bent into a closed blade mold, which always has a seam. This seam may also be one of the hidden dangers of not being able to cut the fiber and causing the product 3.1 and the waste edge 3.2 to be connected after cutting. A positioning block 2.2 is installed inside the closed blade die. The product to be cut is placed on the positioning block 2.2, and the upper die body 1.1 presses the edge of the product onto the blade die 2.1.4, thereby cutting off the waste edge of the product. Slightly different from the punching method in Example 1, the upper die body 1.1 does not insert into the lower die body 2.1 for shearing, but rather... Figure 7 The lower end face of the upper mold body 1.1 presses the product to be cut with waste edges onto the blade mold 2.1.4 for cutting.

[0053] The structure of the lower mold body 2.1 is decomposed into: lower mold top edge plate 2.1.1; blade fixing plate 2.1.2; top edge plate spring 2.1.3; blade 2.1.4; pressure plate 2.1.5; and top edge plate limiting guide rod 2.1.6.

[0054] Apart from the differences from Example 1, the other structures of the plant fiber molded product trimming device described in this embodiment are basically the same as those in Example 1. For example... Figure 5 , Figure 6 , Figure 7 As shown, the stripper plate 1a is also mounted on the upper mold 1 for trimming via stripper plate guide posts 1.4 and limiting rods 1.5. The stripper plate 1a is fitted around the upper mold body 1.1, and can move up and down relative to the upper mold body 1.1 of the upper mold 1 along the stripper plate guide posts 1.4. The limiting rods 1.5 act as a lower limit for the stripper plate 1a. A stripper spring 1.3 is installed between the stripper plate and the upper mold for trimming.

[0055] The lower die 2 for trimming includes: a lower die body 2.1; a positioning block 2.2; a positioning block spring 2.3; a lower mounting plate 2.4; and a positioning block guide post 2.5.

[0056] The lower mold body 2.1 includes: a lower mold top edge plate 2.1.1 located around each positioning block, a top edge plate spring 2.1.3 that applies force vertically upward to the lower mold top edge plate, and a blade mold 2.1.4 fixed between the positioning block and the lower mold top edge plate with the cutting edge facing upward for cutting. Figure 5As can be seen: the blade mold is clamped and fixed by the pressure plate 2.1.5 and the blade fixing plate 2.1.2. The bottom end of the top edge plate limiting guide rod 2.1.6 passes down through the through hole of the bottom mold top edge plate and the top edge plate spring, and is then fixed to the blade fixing plate by threads. Because the diameter of the boss at the top of the top edge plate is larger than that of the through hole, the top edge plate limiting guide rod hooks the top opening of the through hole, so that the bottom mold top edge plate cannot be disengaged from the top edge plate limiting guide rod.

[0057] During the trimming process, the product to be trimmed is first fed onto the positioning block 2.2 of the lower trimming mold 2. The product to be trimmed is accurately positioned on the positioning block 2.2 of the lower trimming mold and waits for trimming.

[0058] The positioning block 2.2 is installed within the blade mold 2.1.4 formed by the blades, and is mounted on the lower trimming mold 2 via the positioning block guide post 2.5. The positioning block 2.2 can move up and down along the positioning block guide post 2.5, thus allowing relative up and down movement of the positioning block relative to the blade mold 2.1.4. A positioning block spring 2.3 is also provided below the positioning block. The positioning block guide post 2.5 has a limiting function, preventing the positioning block spring 2.3 from ejecting the positioning block 2.2 from the lower trimming mold 2, and restricting the positioning block 2.2 to a suitable highest position relative to the blade mold 2.1.4, ensuring that the waste edge 3.2 on the positioning block 2.2 is above the upper cutting edge of the blade mold 2.1.4, but slightly higher than the upper surface of the lower mold top plate 2.1.1. Alternatively, a limiting rod can be separately installed to separate the guiding and limiting functions of the positioning block guide post 2.5.

[0059] The lower mold top plate 2.1.1 is mounted on the blade fixing plate 2.1.2 or directly fixed to the lower mounting plate 2.4 via the top plate limiting guide rod 2.1.6. A top plate spring 2.1.3 is installed between the lower mold top plate 2.1.1 and the blade fixing plate 2.1.2. The lower mold top plate 2.1.1 is fitted around the blade mold 2.1.4. The lower mold top plate 2.1.1 can move up and down relative to the blade mold 2.1.4 along the top plate limiting guide rod 2.1.6. The top plate limiting guide rod 2.1.6 also acts as an upper limit for the lower mold top plate 2.1.1, limiting the highest position of the lower mold top plate 2.1.1.

[0060] During the trimming process, the product to be trimmed is fed onto the positioning block 2.2 of the lower trimming mold 2 to await trimming. The positioning block 2.2 accurately positions the product to be trimmed on the lower trimming mold. The upper trimming mold 1 with the stripper plate 1a moves down. The lower end face of the stripper plate 1a is slightly lower than the lower end face of the upper mold body 1.1. The lower end face of the stripper plate 1a first contacts the waste edge of the product to be trimmed placed on the lower trimming mold 2, and presses the waste edge of the product to be trimmed onto the lower mold top plate 2.1.1 of the lower trimming mold 2. Because the elastic force of the top plate spring 2.1.3 is much greater than that of the stripper spring 1.3, when the stripper plate 1a presses onto the lower mold top plate 2.1.1, the stripper spring 1.3 can further contract while the top plate spring 2.1.3 is hardly compressed further. At this point, the upper die 1 continues to move downward. The lower end face of the upper die 1.1 first presses against the product and the positioning block 2.2 and pushes the positioning block 2.2 downward. Then, the lower end face of the upper die 1.1 presses against the lower die top plate 2.1.1. The upper die 1.1 pushes the positioning block 2.2 and the lower die top plate 2.1.1 downward together. The top plate spring 2.1.3 and the positioning block spring 2.3 are compressed. The stripper plate 1a pressing on the lower die top plate 2.1.1 also moves downward together with the lower die top plate 2.1.1 and the upper die 1.1 until the upper die 1.1 presses the edge of the product to be cut onto the blade die 2.1.4 and cuts off the waste edge.

[0061] After the trimming is completed, the trimming mold 1 moves upward along with the upper mold body 1.1. At this time, the top edge plate spring 2.1.3 and the positioning block spring 2.3 rebound, and the lower mold top edge plate 2.1.1 and the positioning block 2.2 move upward along with the upper mold body 1.1. The upward movement of the lower mold top plate 2.1.1 and the upward movement of the positioning block 2.2 push the cut-off waste edge and the cut-off product above the blade mold 2.1.4 respectively. The upper limit position of the positioning block 2.2 is slightly higher than the upper limit position of the lower mold top plate 2.1.1. The lower mold top plate 2.1.1 moves up to its position first, and then the positioning block 2.2 also moves up to its position (reaching the upper limit position of the positioning block 2.2), so that the position of the cut-off product is higher than the cut-off waste edge. The upper mold 1 for cutting the waste edge continues to move up with the upper mold body 1.1. The upper mold body 1.1 disengages from the positioning block 2.2 carrying the cut-off product, and the stripper plate 1a continues to press the cut-off waste edge 3.2 for a short time under the action of the stripper spring 1.3 until the limit rod 1.5 pulls the stripper plate 1a up and away from the cut-off waste edge. This process completely separates the trimmed product from the cut-off waste edge, and allows the waste edge to remain in the lower mold 2, conveniently placing the trimmed product on top of the cut-off waste edge. This creates conditions for the next step of removing the trimmed product and the waste edge separately.

[0062] The upper cutting mold 1 moves up to position with the unloading plate 1a, and the cut product and the cut waste edge are removed from the lower cutting mold 2. The new product to be cut is then sent to the positioning block 2.2 of the lower cutting mold 2 to wait for cutting.

[0063] Similarly, each upper mold body 1.1 located above each positioning block 2.2 is equipped with a set of sponges, each set of sponges pressing against the product on the positioning block 2.2 during mold closing and trimming. When the upper mold 1 moves upward during mold opening, it ensures that the trimmed product remains on the positioning block 2.2 of the lower mold 2, eliminating the jamming phenomenon of the upper mold body 1.1 on the trimmed product.

[0064] Combining Examples 1 and 2, the edge trimming process of plant fiber molded products is carried out according to the following steps:

[0065] 1) The upper mold 1 with the stripper plate 1a moves down;

[0066] 2) The unloading plate 1a contacts the waste edge of the product to be cut, which is placed on the lower cutting mold 2, and presses the waste edge of the product to be cut onto the lower mold body 2.1 of the lower cutting mold 2;

[0067] 3) The upper mold body 1.1 continues to move downwards, pressing against the positioning block 2.2 with the product. The upper mold body 1.1 pushes the positioning block 2.2 with the product downwards and cuts off the waste edge. The upper mold body 1.1 stops moving downwards.

[0068] 4) The upper cutting mold 1 moves upward along with the upper mold body 1.1, and the positioning block 2.2 of the product after cutting also moves upward with the upper cutting mold 1. The stripper plate 1a continues to press the cut waste edge onto the lower cutting mold 2 so that the product after cutting is completely separated from the waste edge.

[0069] 5) After the positioning block 2.2 of the product with the trimmed edge moves into place, it continues to move up with the upper mold body 1.1 until the stripper plate 1a detaches from the waste edge and moves up with the upper mold of the trimmed edge, while the trimmed waste edge is left on the lower mold 2 of the trimmed edge.

[0070] 6) The upper mold with the stripper plate 1a moves into place;

[0071] 7) The trimmed product and the cut-off waste edges are removed from the trimming lower mold 2;

[0072] 8) The new product to be cut is fed into the positioning block 2.2 of the lower cutting mold 2 to wait for cutting;

[0073] 9) Repeat steps 1 to 8, and repeat the edge trimming operation repeatedly.

Claims

1. A method of trimming flat cut plant fibre moulded articles, characterised in that: An ejector plate (1a) that can move up and down relative to the upper mold body (1.1) is provided on the upper mold (1) for trimming. An ejector spring (1.3) is installed between the ejector plate (1a) and the upper mold (1) for trimming. A positioning block (2.2) that can position the product and a positioning block spring (2.3) that presses the positioning block are provided on the lower mold (2). The positioning block (2.2) can move up and down relative to the lower mold body (2.1) to achieve complete separation of the product and the cut-off waste edge after trimming. The lower end face of the unloading plate is lower than the outer side of the lower end face of the upper mold body; The lower mold body (2.1) further includes: a lower mold top plate (2.1.1) located around each positioning block, a top plate spring (2.1.3) that applies force vertically upward to the lower mold top plate, and a blade mold (2.1.4) fixed with the cutting edge facing upward between the positioning block and the lower mold top plate for cutting edges. The positioning block (2.2) is positioned vertically and vertically within the blade mold, and the lower mold top plate (2.1.1) is positioned vertically and vertically around the blade mold (2.1.4) so ​​that the cut waste edge and the cut edge product are pushed up onto the blade mold (2.1.4) by the upward movement of the lower mold top plate (2.1.1) and the upward movement of the positioning block (2.2), respectively. The outer side of the upper end face of the positioning block is higher than the top edge plate of the lower mold (2.1.1); The trimming process for plant fiber molded products is carried out according to the following steps: The upper cutting mold (1) with the stripper plate (1a) moves down, and the lower end face of the stripper plate (1a) first contacts the waste edge of the product to be cut placed on the lower cutting mold (2), and presses the waste edge of the product to be cut onto the lower mold top plate (2.1.1) of the lower cutting mold (2). The upper cutting mold (1) continues to move down, and the lower end face of the upper mold body (1.1) first presses onto the product and the positioning block (2.2) and pushes the positioning block (2.2) down. Then the lower end face of the upper mold body (1.1) presses onto the lower mold top plate (2.1.1). The mold top plate (2.1.1) and the upper mold body (1.1) push the positioning block (2.2) and the lower mold top plate (2.1.1) down together. The top plate spring (2.1.3) and the positioning block spring (2.3) are compressed. The stripper plate (1a) pressing on the lower mold top plate (2.1.1) also moves down together with the lower mold top plate (2.1.1) and the upper mold body (1.1) until the upper mold body (1.1) presses the edge of the product to be cut onto the blade mold (2.1.4) and cuts off the waste edge. After the trimming is completed, the trimming upper mold (1) moves upward along with the upper mold body (1.1), the top edge plate spring (2.1.3) and the positioning block spring (2.3) rebound, and the lower mold top edge plate (2.1.1) and the positioning block (2.2) move upward along with the upper mold body (1.1); the upward movement of the lower mold top edge plate (2.1.1) and the upward movement of the positioning block (2.2) push the trimmed waste edge and the trimmed product above the blade mold (2.1.4), respectively. The limit position of the upward movement of the positioning block (2.2) is higher than the limit position of the upward movement of the lower mold top edge plate (2.1.1). The lower mold top plate (2.1.1) is moved up to its position first, and then the positioning block (2.2) is also moved up to its position, so that the position of the product after trimming is higher than the cut waste edge. The upper mold (1) for trimming continues to move up with the upper mold body (1.1). The upper mold body (1.1) disengages from the positioning block (2.2) carrying the product after trimming, and the stripper plate (1a) continues to press the cut waste edge (3.2) for a short time under the action of the stripper spring (1.3) until the limit rod (1.5) pulls the stripper plate (1a) up and away from the cut waste edge.

2. A device for trimming flat cut plant fiber molded articles, characterized in that: The trimming device includes: an upper trimming mold (1) and a lower trimming mold (2). The upper trimming mold (1) is provided with a stripper plate (1a) that can move up and down relative to the upper mold body (1.1). A stripper spring (1.3) is installed between the stripper plate (1a) and the upper trimming mold (1). The lower trimming mold (2) is provided with a plurality of positioning blocks (2.2) that can position the product. A positioning block spring (2.3) is installed between the positioning block and the lower mounting plate (2.4) so ​​that the positioning block (2.2) can move up and down relative to the lower mold body (2.1) to achieve complete separation of the product and the cut-off waste edge after trimming. The lower end face of the unloading plate is lower than the outer side of the lower end face of the upper mold body; The lower mold body (2.1) further includes: a lower mold top plate (2.1.1) located around each positioning block, a top plate spring (2.1.3) that applies force vertically upward to the lower mold top plate, and a blade mold (2.1.4) fixed with the cutting edge facing upward between the positioning block and the lower mold top plate for cutting edges; the positioning block (2.2) is positioned vertically and vertically within the blade mold, and the lower mold top plate (2.1.1) is positioned vertically and vertically around the blade mold (2.1.4), so that the cut waste edge and the cut edge product are pushed up onto the blade mold (2.1.4) by the upward movement of the mold top plate (2.1.1) and the upward movement of the positioning block (2.2); The outer side of the upper end face of the positioning block is higher than the top edge plate of the lower mold (2.1.1); The lower end face of the upper mold body (1.1) can press against the top edge plate of the lower mold (2.1.1) and push the positioning block (2.2) and the top edge plate of the lower mold (2.1.1) to move down together.

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