Saw blade type punch structure

Abstract

The objective of the present invention is to provide a sawtooth-type punch structure. The configuration of the present invention is characterized by including a sawtooth-type punch (130) mounted on a mold (120) of a electrode plate cutting device, and a sawtooth-type blade part (132) provided at the lower end of the sawtooth-type punch (130) for performing side cutting of an electrode plate for a secondary battery.

Description

Technology Field

[0001] The present invention relates to a sawtooth-type punch structure, and more specifically, to a sawtooth-type punch structure developed to solve the existing problem in which side cutting is performed on separate equipment after cutting an electrode for a secondary battery, which leads to an increase in process steps and frequent defects. Background Technology

[0003] Generally, a secondary battery has a process for forming an electrode assembly comprising a positive plate coated with a positive active material, a negative plate coated with a negative active material, and a separator interposed between the positive and negative plates, and there is an electrode plate cutting process for forming the electrode assembly by cutting the reel plates into individual square plates using a punch.

[0004] When manufacturing a secondary battery, a substrate on which an active material layer is formed is cut into length units of a secondary battery electrode using an electrode cutting device to form a secondary battery electrode.

[0005] When a positive electrode substrate or a negative electrode substrate coated with a positive electrode active material or a negative electrode active material is supplied between an upper punch and a lower punch to a secondary battery electrode plate cutting device, the substrate is cut into a secondary battery electrode plate by the operation of the punch.

[0006] However, in the conventional method, the electrode is cut using upper and lower molds (120), and the side cutting is performed on separate equipment, so there is a problem of frequent defects occurring along with an increase in the process.

[0007] To solve this, attempts were made to simultaneously cut the sides of the electrode plates in mid-air, but the existing flat diagonal punch shape resulted in poor cross-sectional quality (tearing or burr), so it is not being applied in the industry. Prior art literature

[0009] Patent Publication No. 10-2026-0003899 Patent Publication No. 10-2022-0098178 The problem to be solved

[0010] The objective of the present invention is to provide a sawtooth-type punch structure that addresses the existing problem of frequent defects and increased process complexity caused by performing side cutting on separate equipment after cutting a secondary battery electrode, thereby providing characteristics such as process reduction and prevention of defects by developing a sawtooth-type structure.

[0011] The technical problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0013] According to the present invention for solving the above-mentioned problem, a sawtooth punch structure is provided, characterized by including a sawtooth punch (130) mounted on a mold (120) of a electrode plate cutting device and a sawtooth blade part (132) provided at the lower end of the sawtooth punch (130) for performing side cutting of an electrode plate for a secondary battery.

[0014] The above mold (120) is composed of a lower mold (125) provided in the electrode plate cutting device and an upper mold (123) positioned in the electrode plate cutting device so as to be vertically movable above the lower mold (125), and the saw blade punch (130) equipped with the saw blade part (132) is configured to be slidably coupled to the upper mold (123).

[0015] The lower part of the sawtooth-shaped punch (130) is characterized by having sawtooth-shaped blade sections (132) arranged on both sides based on the middle blade-side concave groove (134), so that the sawtooth-shaped punch (130) is configured in a U-shaped blade shape.

[0016] The saw blade portion (132) positioned on both the left and right sides of the blade-side concave groove (134) is characterized by being configured in a shape having a plurality of triangular saw blades (132TB) that are positioned at regular intervals toward the front and rear ends of the saw blade punch (130) and have pointed ends at their lower ends.

[0017] The above triangular saw blade (132TB) is characterized by having a left-right symmetrical blade surface that is inclined upward with respect to the center when viewed from one side of the saw blade punch (130), and has a triangular saw blade shape with a pointed end at the bottom.

[0018] Inside the upper die (123), a pair of front and rear tap punches (140) are provided in a direction perpendicular to the front and rear ends of the saw blade punch (130), and on the bottom surface of the pair of tap punches (140), a tap punch side blade (142) for forming an electrode tab on a secondary battery electrode plate is provided, and on the tap punch side blade (142) of at least one of the pair of tap punches (140), a U-shaped tap forming blade (142TB) for forming a tab on at least one of the front and rear ends of the electrode plate is provided, and the pair of tap punches (140) are characterized by having a guide part function that performs the role of suppressing shaking even in open air by punching the secondary battery electrodes up and down simultaneously and aligning the secondary battery electrodes in close contact. Effects of the invention

[0020] The present invention was developed with a sawtooth punch structure to solve the existing problem of frequent defects occurring with increasing process steps. By applying the newly developed sawtooth punch, the present invention has the effect of stably ensuring cross-sectional quality even during air cutting of electrode plates and preventing electrode plate quality defects.

[0021] The effects according to the present invention are not limited to those exemplified above, and a wider variety of effects are included within the present invention. That is, the effects of the present invention are not limited to those mentioned above, and various effects may be included within the scope obvious to a person skilled in the art from the description below. Brief explanation of the drawing

[0023] FIG. 1 is a perspective view showing the mold structure of a secondary battery electrode plate cutting device employing a sawtooth-type punch structure according to the present invention. FIG. 2 is a side view of FIG. 1, FIG. 3 is a drawing showing an enlarged view of a part of the sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention, from the bottom of the upper die. FIG. 4 is a drawing showing an enlarged view of a part of the tap punch, which is a main part of the sawtooth-shaped punch structure according to the present invention, from the bottom of the upper die. FIG. 5 is a drawing that omits the upper die shown in FIG. 3 and shows an enlarged view of a part of the main component, the sawtooth-shaped punch. FIG. 6 is a drawing that omits the upper die shown in FIG. 3 and shows an enlarged view of a part of the main part, the tap punch. FIG. 7 is a drawing showing the upper die and lower die of a secondary battery electrode plate cutting device employing a sawtooth-type punch structure according to the present invention. FIG. 8 is a perspective view showing the structure of a sawtooth punch and a tap punch, which are the main parts of the present invention, from the bottom view. FIG. 9 is a bottom perspective view of a sawtooth punch and a tap punch, which are the main parts of the present invention. FIG. 10 is a left-side perspective view of FIG. 9, FIG. 11 is a side view of FIG. 9, FIG. 12 is a front cross-sectional view showing an enlarged portion of a sawtooth-shaped punch, which is a main part of the present invention. FIG. 13 is a perspective view showing a part of a modified embodiment of a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention. FIG. 14 is a front view of FIG. 1, FIG. 15 is an enlarged view of the main part of FIG. 14, FIG. 16 is a cross-sectional view showing a part of another modified embodiment of a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention. FIG. 17 is a perspective view showing a part of another modified embodiment of a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention. FIG. 18 is a cross-sectional view showing a part of an embodiment in which a microhole is formed in a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention. Specific details for implementing the invention

[0024] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. The objectives, features, and advantages of the present invention will be more easily understood by referring to the attached drawings and the following detailed description. Furthermore, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the present invention, such detailed description is omitted.

[0025] Additionally, terms such as first, second, A, B, (a), (b), etc., may be used when describing the components of the present invention. These terms are intended only to distinguish the components from other components, and the essence, order, or sequence of the components is not limited by the terms. Where it is stated that a component is "connected," "combined," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other component, but that another component may also be "connected," "combined," or "connected" between each component.

[0026] Furthermore, specific structural or functional descriptions in the present invention are illustrative of embodiments according to the concept of the present invention merely for the purpose of explaining embodiments according to the concept of the present invention, and embodiments according to the concept of the present invention may be implemented in various forms and should not be interpreted as being limited to the embodiments described in this specification or application.

[0028] FIG. 1 is a perspective view showing the mold structure of a secondary battery electrode plate cutting device employing a sawtooth-type punch structure according to the present invention; FIG. 2 is a side view of FIG. 1; FIG. 3 is a drawing showing an enlarged view of a part of the sawtooth-type punch, which is a main part of the sawtooth-type punch structure according to the present invention, from the bottom of the upper mold; FIG. 4 is a drawing showing an enlarged view of a part of the tap punch, which is a main part of the sawtooth-type punch structure according to the present invention, from the bottom of the upper mold; FIG. 5 is a drawing showing an enlarged view of a part of the sawtooth-type punch, which is a main part, with the upper mold shown in FIG. 3 omitted; FIG. 6 is a drawing showing an enlarged view of a part of the tap punch, which is a main part, with the upper mold shown in FIG. 3 omitted; FIG. 7 is a drawing showing the upper mold and lower mold of a secondary battery electrode plate cutting device employing a sawtooth-type punch structure according to the present invention; FIG. 8 is a perspective view showing the structure of the sawtooth-type punch and the tap punch, which are main parts of the present invention, from the bottom; FIG. 9 is a bottom perspective view of the sawtooth-type punch and the tap punch, which are main parts of the present invention; FIG. 10 is a left-side perspective view of FIG. 9, FIG. 11 is a side view of FIG. 9, and FIG. 12 is a front cross-sectional view showing an enlarged portion of a sawtooth-shaped punch, which is a main part of the present invention.

[0029] Referring to the drawings, the present invention includes, as a basic configuration, a saw-blade type punch (130) mounted on a mold (120) of a electrode plate cutting device, having a saw-blade type blade part (132) for cutting an electrode plate for a secondary battery provided at the lower end.

[0030] In the present invention, the mold (120) is composed of a lower mold (125) and an upper mold (123).

[0031] The lower die (125) is provided in a plate cutting device. The lower die (125) can be configured to be placed on the main cutting die, which is the main part of the plate cutting device.

[0032] The upper mold (123) is positioned on the electrode plate cutting device so as to be vertically movable above the lower mold (125). The upper mold (123) is connected to the cylinder rod of a pressing cylinder supported on the main frame of the electrode plate cutting device, and the upper mold (123) may be configured to descend toward the lower mold (125) and rise upward from the lower mold (125) by means of a lifting mechanism, such as a pressing cylinder provided in a known press device, such as a pressing cylinder, as the upper mold (123) descends toward the lower mold (125) as the cylinder rod of the pressing cylinder descends.

[0033] The sawtooth-shaped punch (130) is equipped with the sawtooth-shaped blade portion (132), and the sawtooth-shaped punch (130) is slidably coupled to the upper die (123). The upper mold (123) is connected to an upper base upper mold panel (101) coupled to a plate cutting device via a cushioning connecting means such as a spring, and while the upper mold (123) is lowered to contact the lower mold (125), the cushioning connecting means is compressed, causing the upper mold (123) to rise above the lower mold (125). The saw blade punch (130) is mounted on an upper punch support frame (not shown), and the upper punch support frame is connected to the lifting operating device. While the upper mold (123) is lowered to contact the lower mold (125), the cushioning connecting means is compressed, causing the upper mold (123) to rise above the lower mold (125), and the saw blade punch (130) protrudes from the bottom surface of the upper mold (123) and enters the saw blade punch (130) insert hole in the lower mold (125).

[0034] At this time, the saw-shaped blade portions (132) are arranged on both sides of the lower part of the saw-shaped punch (130) based on the middle blade-side concave groove (134), so that the saw-shaped punch (130) is configured in a U-shaped blade shape.

[0035] The saw blade portion (132) positioned on both the left and right sides of the blade-side concave groove (134) is configured to have a shape having a plurality of triangular saw blades (132TB) that are positioned at regular intervals toward the front and rear ends of the saw blade punch (130) and have pointed ends at their lower ends.

[0036] The above triangular saw blade (132TB) has a left-right symmetrical blade surface that is inclined upward with respect to the center when viewed from one side of the saw blade punch (130), and has a triangular saw blade shape with a pointed end at the bottom.

[0037] Meanwhile, the above sawtooth-shaped punch (130) is further characterized by having a guide surface (132GF) that is downwardly inclined from the inner end of a plurality of the above triangular sawtooth-shaped blades (132TB) toward the blade-side concave groove (134).

[0038] Additionally, a pair of front and rear tap punches (140) are provided inside the upper die (123) and positioned perpendicularly to the front and rear ends of the sawtooth punch (130).

[0039] A pair of tap punches (140) are configured in a straight punch shape, and a tap punch side blade (142) for forming an electrode tab on a secondary battery electrode plate is provided on the bottom surface of the pair of tap punches (140).

[0040] At this time, the tap punch side blade (142) of at least one of the pair of tap punches (140) is provided with a U-shaped tap forming blade (142TB) for forming a tap on at least one of the front and rear ends of the electrode plate.

[0041] A pair of the above-mentioned tap punches (140) simultaneously punch the secondary battery electrodes up and down, and function as guide parts that align the secondary battery electrodes in close contact at a constant rate to suppress shaking even during air cutting.

[0043] According to the present invention with the above configuration, a sawtooth punch (130) slide hole is formed through the upper and lower surfaces of the upper mold (123), and the sawtooth punch (130) is slidably coupled to the sawtooth punch (130) slide hole. The upper mold (123) is provided with a pair of front and rear tap punch (140) slide holes in a direction perpendicular to the sawtooth punch (130) slide hole, and a pair of front and rear tap punches (140) are slidably coupled to the tap punch (140) slide holes. The upper mold (123) is lowered so as to be in close contact with the lower mold (125), and the sawtooth punch (130) and the tap punch (140) protrude downward from the bottom surface of the upper mold (123) and enter the sawtooth punch (130) insert hole and the tap punch (140) insert hole in the lower mold (125). At this time, the Since the secondary battery electrode plate is supplied between the upper mold (123) and the lower mold (125), the electrode plate is cut in a side direction by the saw blade punch (130), and while the pair of tab punches (140) are fixed so that the electrode plate is in close contact with the lower mold (125), an electrode tab is formed at least one end of the upper and lower parts of the electrode by a U-shaped tab forming blade (142TB) protruding from the lower part of one of the tab punches (140).

[0044] The present invention relates to a sawtooth-type punch structure that enables side cutting, which was previously performed as a separate process, to be performed simultaneously with upper and lower punching in a Press Type mold (120) for cutting COF film or secondary battery electrodes. The structure implements a process shortening structure by configuring a punch shape having a sawtooth shape, a cutting angle, and an inclined surface within the mold (120) so that stable cutting is performed even in the air while a reel-shaped electrode plate passes through.

[0045] The present invention was developed with a sawtooth punch structure in consideration of the fact that, in the past, after cutting the electrode with the upper and lower molds (120), the side cutting is performed on separate equipment, which leads to increased process steps and defects, and that the industry does not apply conventional flat / slanted punch shapes because they cause cross-sectional quality defects (tearing, burrs). By applying the newly proposed sawtooth punch (130), the cross-sectional quality is stably secured even when cutting the electrode plate in mid-air.

[0046] Considering that the strength of the electrode plate (Al, Cu + active material) varies in a certain direction due to its physical properties, it can be said that the cutting angle shape of the saw blade contributed to the improvement of the electrode plate's quality.

[0047] This invention features a shape not used in existing technology, and clearly demonstrates effects such as shortening the notching process, miniaturizing equipment, and reducing defects.

[0048] To explain the technical logic of the saw blade + guide structure of the saw blade type punch (130) in the present invention, the saw blade shape has a cutting function optimized for the composite structure of a metal foil-based electrode film, unlike a simple tape cutter structure, and the guide structure performs the role of suppressing shaking even in open-air cutting by aligning the film in close contact at a constant rate.

[0049] Accordingly, the saw blade + guide structure of the blade-shaped punch of the present invention enables side cutting of the electrode plate to be achieved using only the upper mold (123) and the lower mold (125) without a separate process device.

[0050] Meanwhile, the guide structure refers to a pair of tap punches (140) that perform the function of suppressing shaking even in air cutting by punching the secondary battery electrodes up and down simultaneously and aligning the secondary battery electrodes in close contact.

[0051] Consequently, in order to solve the existing problem where defects occur frequently along with the increase in process steps, the present invention utilizes a sawtooth punch structure. By applying a newly developed sawtooth punch, it is possible to expect the effect of stably ensuring cross-sectional quality even during air cutting of electrode plates and preventing electrode plate quality defects.

[0052] In addition, in the present invention, the triangular saw blade (132TB) is configured with a triangular saw blade shape with a pointed end at the bottom, having a left-right symmetric blade surface that is inclined upward with respect to the center when viewed from one side of the saw blade punch (130). Therefore, since it has an asymmetric wedge blade structure that is inclined in one direction rather than left-right symmetry, the stress generated when cutting the side of the electrode plate by the saw blade is concentrated to one side (scrap side), and as a result, the cross-sectional deformation of the electrode plate used as an actual battery is suppressed to the extreme, thereby allowing for the expectation of an effect that optimizes conductivity.

[0053] In addition, the present invention further provides a guide surface (132GF) that is downwardly inclined from the inner end of a plurality of triangular saw blades (132TB) toward the blade-side concave groove (134), thereby more effectively performing the function of concentrating the stress generated during the side cutting of the electrode plate to one side (scrap side) by the two saw blade sections (132) arranged side by side on the left and right of the saw blade punch (130), and as a result, the cross-sectional deformation of the electrode plate used as an actual battery is suppressed to the extreme, thereby allowing for the effect of more effectively optimizing conductivity.

[0054] In addition, the present invention has a blade-side concave groove (134) formed between left and right parallel saw blade-shaped blade parts (132), so that scrap generated when cutting the electrode plate enters the blade-side concave groove, thereby preventing the scrap from having a negative effect when cutting the electrode plate.

[0055] Meanwhile, FIG. 13 is a perspective view showing a part of a modified embodiment of a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention; FIG. 14 is a front view of FIG. 1; FIG. 15 is an enlarged view of the main part of FIG. 14; FIG. 16 is a front cross-sectional view showing a part of another modified embodiment of a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention; FIG. 17 is a perspective view showing a part of another modified embodiment of a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention; and FIG. 18 is a front cross-sectional view showing a part of an embodiment in which a microhole is formed in a sawtooth punch, which is a main part of the sawtooth punch structure according to the present invention.

[0056] Referring to the drawings, the present invention is characterized by further including a plurality of nano-cutting blades (152) provided at the tip of the saw blade of the saw blade-type punch (130). Nano-cutting blades (152) with a fine tooth shape can be formed at the tip of the saw blade of the saw blade-type punch (130) through nanometer (nm) laser processing. These nano-cutting blades (152) are blades with a fine saw-like shape that is invisible to the naked eye. The nano-cutting blades (152) can be configured in the shape of a triangular blade with a pointed tip. Meanwhile, it should be noted that in the present invention, the nano-cutting blades (152) are depicted to appear larger than they actually are for ease of understanding.

[0057] Therefore, the present invention has the effect of minimizing burrs generated when cutting electrode plates and preventing shedding of active material. In addition, it has the effect of precisely cutting the metal foil (mainly Cu metal foil or aluminum metal foil) which is the current collector of the electrode plate without tearing it, thereby ensuring high quality when cutting the electrode plate.

[0058] In addition, the present invention is characterized by further forming a high-strength coating layer (162) on the saw blade portion (132) of the saw blade punch (130) and on the entire surface of the saw blade punch. In the present invention, the high-strength coating layer (162) may be composed of a DLC (Diamond-Like Carbon) coating layer.

[0059] Accordingly, the present invention has the effect of making the side cutting of the electrode plate smoother by increasing the hardness of the sawtooth punch (130) and lowering the friction coefficient due to the high-strength coating layer (162), and by lowering the friction coefficient with the electrode plate during the side cutting of the electrode plate, it prevents the electrode plate cutting surface from becoming uneven due to friction during the side cutting of the electrode plate, thereby ensuring the quality of the electrode plate side cutting surface.

[0060] In addition, the present invention forms micro-holes (172), which are micro-pores, inside the saw blade punch (130) so that cooling air enters the interior of the saw blade punch (130), and is configured so that a plurality of micro-holes (172), which are micro-pores, communicate with the outer surface of the saw blade punch (130), thereby allowing cooling air to be sprayed to the outside of the saw blade punch (130) through a plurality of micro-holes (172), so that frictional heat can be immediately removed during electrode plate cutting. Micro-holes (172), which are micro-pores, are formed near the saw blade part (132) of the saw blade punch (130) to cool the frictional heat generated during electrode plate cutting and to scatter dust.

[0061] Accordingly, the present invention prevents a decrease in the precision of cutting the electrode plate due to thermal deformation and prevents dust from adhering to the electrode plate due to dust scattering during cutting, thereby ensuring the quality of the electrode plate and further extending the replacement cycle of the saw blade type punch (130).

[0063] Specific embodiments of the present invention have been described above. However, those skilled in the art will understand that the spirit and scope of the present invention are not limited to these specific embodiments, and that various modifications and variations are possible within the scope of not altering the essence of the invention.

[0064] Accordingly, the embodiments described above are provided to fully inform those skilled in the art of the scope of the invention and should be understood as illustrative in all respects and not restrictive, and the invention is defined only by the scope of the claims. Explanation of the symbols

[0066] 120. Mold 123. Prize Type 125. Lower mold 130. Sawtooth Punch 132. Serrated blade section 132TB. Triangular serrated blade 132GF. Guide surface 134. Edge-side concave groove 140. Tap Punch 142. Tap punch side blade 142TB. Tabforming blade 152. Nano cutting blade 162. High-strength coating layer 172. Microhole

Claims

Claim 1 A sawtooth-shaped punch structure comprising a sawtooth-shaped punch (130) mounted on a mold (120) of a electrode plate cutting device, and a sawtooth-shaped blade section (132) provided at the lower end of the sawtooth-shaped punch (130) for performing side cutting of an electrode plate for a secondary battery, wherein the mold (120) is composed of a lower mold (125) provided in the electrode plate cutting device and an upper mold (123) positioned in the electrode plate cutting device so as to be vertically movable above the lower mold (125), wherein the sawtooth-shaped punch (130) equipped with the sawtooth-shaped blade section (132) is slidably coupled to the upper mold (123), and wherein the sawtooth-shaped blade section (132) is positioned on each side of the lower end of the sawtooth-shaped punch (130) based on a blade-side concave groove (134) in the middle, so that the sawtooth-shaped punch (130) is configured in a U-shaped blade shape. Claim 2 delete Claim 3 delete Claim 4 A sawtooth punch structure according to claim 1, wherein the sawtooth blade portions (132) arranged on both the left and right sides of the blade-side concave groove (134) are arranged at regular intervals toward the front and rear ends of the sawtooth punch (130) and are configured to have a shape having a plurality of triangular sawtooth blades (132TB) with pointed ends at their lower ends. Claim 5 In claim 4, the triangular saw blade (132TB) is characterized by having a left-right symmetrical blade surface that is inclined upward with respect to the center when viewed from one side of the saw blade punch (130), and has a triangular saw blade shape with a pointed end at the bottom. Claim 6 In claim 1, a pair of front and rear tap punches (140) are provided in the interior of the upper die (123) in a direction perpendicular to the front and rear end portions of the saw blade punch (130), and a tap punch side blade (142) for forming an electrode tab on a secondary battery electrode plate is provided on the bottom surface of the pair of tap punches (140), and a U-shaped tap forming blade (142TB) for forming a tab on at least one of the front and rear end portions of the electrode plate is provided on the tap punch side blade (142) of at least one of the pair of tap punches (140), and the pair of tap punches (140) are characterized by having a guide portion function that suppresses shaking even in open-air cutting by punching the secondary battery electrodes up and down simultaneously and aligning the secondary battery electrodes in close contact.

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