Power transmission unit for electrode cutting apparatus

Abstract

The present invention relates to a power transmission unit for an electrode cutting apparatus, the power transmission unit including: a lifting block including a structure that is installed to a main frame to be able to move up and down; an upper frame to which an upper cutter holder is installed, the upper cutter holder having an upper cutter configured to cut an electrode sheet fixed thereto; a connecting shaft configured to connect the lifting block and the upper frame to each other; and an elastic member located at an upper portion of the connecting shaft.

Description

Technical Field

[0001] This application claims the benefit of priority to Korean Patent Application No. 2020-0092585, filed on July 24, 2020, the entire disclosure of which is incorporated herein by reference.

[0002] The present invention relates to a power transmission unit for an electrode cutting device, and more specifically, to a power transmission unit for an electrode cutting device configured to have the following structure, wherein a lifting block, which is movable up and down and mounted to the main frame to correct the parallelism between an upper cutter and a lower cutter configured to cut electrode sheets, is loosely coupled to a connecting shaft, and the connecting shaft is coupled to an upper frame that fixes the upper cutter. Background Technology

[0003] Rechargeable and dischargeable lithium-ion batteries have been widely used as a power source for wireless mobile devices or wearable devices, and have also been used as a power source for electric vehicles and hybrid electric vehicles proposed as alternatives to existing gasoline and diesel vehicles that cause air pollution.

[0004] The lithium secondary battery includes: an electrode assembly comprising a positive electrode plate coated with a positive electrode active material, a negative electrode plate coated with a negative electrode active material, and a stack of a separator located between the positive and negative electrode plates, the separator being configured to prevent short circuits and to allow lithium ions (Li-ion) to move through the separator; a battery housing configured to house the electrode assembly; and an electrolyte injected into the battery housing to allow lithium ions to move.

[0005] Typically, positive and negative electrode plates are manufactured by coating elongated positive and negative electrode plates with positive and negative active materials respectively, drying and rolling the active materials, and cutting the positive and negative electrode plates into predetermined sizes to manufacture unit electrodes.

[0006] A conventional electrode plate cutting device configured to manufacture unit electrodes includes: a supply unit configured to supply the electrode plate in a positioned state; and a cutter mounted on one side of the supply unit. The cutter consists of an upper cutter and a lower cutter. Specifically, with the electrode plate as a reference, the upper cutter is fixed to the upper side of the electrode plate, and the lower cutter is mounted on the lower side of the electrode plate. At the electrode plate cutting position, the upper cutter moves downwards or the lower cutter moves upwards. Therefore, when the electrode plate is supplied to the cutting device, the edges of the upper cutter and the lower cutter contact each other to cut the electrode plate.

[0007] However, when the cutting process using the upper and lower cutters is repeatedly performed, the edges of the upper and lower cutters wear and bend, resulting in the electrode plate being cut in an uneven or burr-prone state.

[0008] Furthermore, if the mounting surfaces of the upper and lower cutters are not aligned, the cutters will inevitably operate after repeated wear. In this case, the clearance between the upper and lower cutters gradually increases due to the reduction in the width of the cutters, leading to damage to the edges of the cutters and an increase in the amount of foreign matter, thus producing defective electrode assemblies.

[0009] Related to this, Figure 1 This is a side view and a partial enlarged view of a conventional electrode cutting device, showing a portion of the device having a chain-like assembly structure in which the components of the upper and lower units are directly fastened to the main frame step by step.

[0010] Reference Figure 1 Conventional electrode cutting equipment uses a system in which lateral pressure is used to align the upper cutter 21 and the lower cutter 25. Due to the difference in lateral pressure D and the distance between the lateral pressure axis and the end of the upper cutter 21, the upper cutter 21 tilts, causing deformation of the surfaces where the upper cutter 21 and the lower cutter 25 engage. Therefore, to prevent the upper cutter from tilting, a headless bolt 15 is used to push the upper cutter 21 in the direction opposite to the lateral pressure.

[0011] In addition, the connecting shaft 30, which is configured to connect the lifting block 10 and the upper frame 20 to each other, is securely connected to the lifting block 10 by bolts.

[0012] Therefore, when a parallelism tolerance occurs between the up-and-down movement of the lifting block 10 and the up-and-down movement of the upper frame 20, the upper cutter 21 will deform.

[0013] To address this issue, a method was employed to fine-tune the tightening distance of the headless bolt 15. However, this method is highly complex, time-consuming, and yields unsatisfactory results.

[0014] As a related technology, Patent Document 1 discloses an electrode plate cutting device, including: a main body unit constituting the main body of the cutting device; and a cutter unit, the cutter unit including an upper cutter and a lower cutter configured to cut the electrode plate, and a gap adjusting component configured to automatically adjust the gap between the upper cutter and the lower cutter.

[0015] In Patent Document 1, in order to prevent the gap between the upper cutter and the lower cutter from increasing as the number of cuts by the electrode plate increases, a gap adjustment component is provided that is configured to automatically adjust the gap between the upper cutter and the lower cutter.

[0016] The gap adjustment component is configured to apply pressure to the lower cutter to maintain a uniform gap between the lower and upper cutters. The gap adjustment component is composed of an elastic member such as a spring. However, this patent document does not propose a method for maintaining the parallelism between the upper and lower cutters.

[0017] (Existing technical literature)

[0018] (Patent Document 1) Korean Patent Publication No. 1106337 (January 9, 2012) Summary of the Invention

[0019] Technical issues

[0020] The present invention was made in view of the above problems. The object of the present invention is to provide a power transmission unit for an electrode cutting device, which includes a structure that can prevent non-uniformity of the cutting surface of the electrode sheet and reduction of cutting force caused by the gap tolerance between the upper and lower cutters of the electrode cutting device due to repeated cutting of the electrode sheet.

[0021] Technical solution

[0022] To achieve the above objectives, the power transmission unit for an electrode cutting device according to the present invention includes: a lifting block, the lifting block having a structure capable of being movably mounted to a main frame; an upper frame, an upper cutter holder mounted to the upper frame, the upper cutter holder having an upper cutter configured for cutting electrode sheets fixed thereon; a connecting shaft configured to connect the lifting block and the upper frame to each other; and an elastic member located at the upper part of the connecting shaft.

[0023] In the power transmission unit according to the present invention, the elastic member may be a spring or rubber.

[0024] In the power transmission unit according to the invention, the connecting shaft can be inserted into and engaged with a recess formed in the upper frame.

[0025] In the power transmission unit according to the present invention, the lifting block may be provided with a recess configured to accommodate the connecting shaft and the elastic member.

[0026] In the power transmission unit according to the present invention, the upper frame can be slidably fastened to the lifting block while engaged with the connecting shaft.

[0027] In the power transmission unit according to the invention, the connecting shaft can be loosely coupled to the lifting block via the elastic member located below the fixing screw that engages with the lifting block.

[0028] In the power transmission unit according to the present invention, the connecting shaft may include a first connecting shaft and a second connecting shaft, a fixed frame fixed to the lifting block may be provided on the first connecting shaft and the second connecting shaft, and the elastic member may be provided on the upper part of the fixed frame.

[0029] In the power transmission unit according to the invention, the pressing force and elastic force of the elastic member relative to the fixed frame can be applied equally to the first connecting shaft and the second connecting shaft.

[0030] Furthermore, even if a parallelism tolerance exists between the up-and-down movement of the upper frame used to cut the electrode sheet and the up-and-down movement of the lifting block, the straightness of the up-and-down movement of the upper frame can be guaranteed.

[0031] Furthermore, the present invention provides a method for assembling the power transmission unit, comprising the following steps: (a) preparing a lifting block to be installed on the main frame; (b) fixing a connecting shaft to the upper frame; (c) fastening the upper frame to the lifting block by sliding the connecting shaft; (d) providing an elastic member on the upper part of the connecting shaft through a through hole in the lifting block; and (e) fastening a fixing screw to the through hole in the lifting block to fix the elastic member.

[0032] In the method according to the invention, in step (c), the upper frame can be slidably fastened to the lifting block while a fixed frame is provided in the recess formed in the lifting block.

[0033] Beneficial effects

[0034] As can be seen from the above description, the power transmission unit for the electrode cutting device according to the present invention is configured such that the upper frame and the lifting block mounted to the main frame to provide the power required for the up-and-down movement of the upper frame are fastened to each other with an elastic member provided between the upper frame and the lifting block, thereby loosely connecting the upper frame and the lifting block.

[0035] Therefore, even if parallelism tolerances occur between the lifting block and the upper frame when the lifting block and the upper frame move up and down, the straightness of the upper frame can still be guaranteed.

[0036] As the straightness of the upper frame is ensured as described above, fluctuations in the gap between the upper and lower cutters can be prevented during repeated cutting of the electrode sheet.

[0037] Therefore, the cut surface of the electrode sheet will not bend or produce burrs, which can prevent the separation of the electrode mixture layer and maintain a high cutting force uniformly.

[0038] In addition, it can reduce the calibration time required to maintain the parallelism between the upper and lower cutters, thereby improving productivity. Attached Figure Description

[0039] Figure 1 These are side views and enlarged partial views of a conventional electrode cutting device.

[0040] Figure 2 This is a cross-sectional perspective view of a power transmission unit for an electrode cutting device according to the present invention.

[0041] Figure 3 yes Figure 2 Side view.

[0042] Figure 4 This is a perspective view of a part of the power transmission unit used in electrode cutting equipment.

[0043] Figure 5 This is a partial perspective view showing the power transmission unit for the electrode cutting equipment mounted on the main frame.

[0044] Figure 6 It is based on the cut surface of the electrode sheet of the comparative example.

[0045] Figure 7 It is the cut surface of the electrode sheet according to the embodiment. Detailed Implementation

[0046] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, enabling those skilled in the art to readily implement these preferred embodiments. However, in describing the working principle of the preferred embodiments of the present invention, detailed descriptions of known functions and structures incorporated herein may obscure the main points of the invention, and such descriptions will be omitted.

[0047] Furthermore, the same reference numerals will be used throughout the accompanying drawings to denote components performing similar functions or operations. Where, throughout the application, one component is referred to as being connected to another component, that one component may not only be directly connected to the other component, but also indirectly connected to the other component via another component. Moreover, including an element does not imply the exclusion of other elements, but rather the inclusion of further elements, unless otherwise stated.

[0048] Furthermore, unless otherwise specified, the description of elements by limitation or addition can be applied to all inventions and does not limit any particular invention.

[0049] Furthermore, in the specification of this invention and the claims of this application, unless otherwise stated, the singular form is intended to include the plural form.

[0050] Furthermore, in the specification of this invention and the claims of this application, unless otherwise stated, "or" includes "and". Therefore, "including A or B" refers to three cases: including A, including B, and including both A and B.

[0051] Furthermore, unless the context explicitly indicates otherwise, all numerical ranges include the minimum value, the maximum value, and all intermediate values ​​in between.

[0052] Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0053] Figure 2 This is a cross-sectional perspective view of a power transmission unit for an electrode cutting device according to the present invention. Figure 3 yes Figure 2 Side view.

[0054] Reference Figure 2 and Figure 3 The power transmission unit for an electrode cutting device according to the present invention includes: a lifting block 100, the lifting block 100 including a structure that is movably mounted to a main frame (not shown); an upper frame 200, an upper cutter holder 220 mounted to the upper frame 200, the upper cutter holder 220 having an upper cutter 210 configured for cutting electrode sheets fixed thereon; a connecting shaft 300, the connecting shaft 300 being configured to connect the lifting block 100 and the upper frame 200 to each other; and an elastic member 400 located at the upper part of the connecting shaft 300.

[0055] When the electrode sheet is supplied via the supply roller, the main frame moves synchronously with the supply speed of the electrode sheet and moves in the supply direction of the electrode sheet. When the relative speed between the main frame and the electrode sheet in the supply direction becomes 0, the upper frame moves up and down to cut the electrode sheet.

[0056] Subsequently, when the main frame returns to the point where the work began, one cycle is completed, and the electrode sheet is cut while the cycle is repeated.

[0057] The lifting block 100 is provided with a recess configured to accommodate the connecting shaft 300 and the elastic member 400. The upper frame 200 can be integrally connected to the lower frame 260 on which the lower cutter 250 is installed, and the connecting shaft 300 is connected to the upper frame 200 in a state of engagement with the upper frame 200, and is slidably fixed to the recess formed in the lifting block 100.

[0058] Therefore, the upper and lower frames can be easily installed into the electrode cutting equipment.

[0059] The elastic member 400 is located above the connecting shaft 300 inserted into the recess formed in the lifting block 100 and below the fixing screw 110 that is coupled to the lifting block 100. The elastic member 400 has a height that is sufficient to contract in the recess by inserting the fixing screw.

[0060] Therefore, the power generated by the up-and-down movement of the lifting block can be transmitted to the upper frame via the elastic member and the connecting shaft. However, in the power transmission unit for the electrode cutting device according to the present invention, the elastic member is disposed in the upper frame, so the lifting block and the connecting shaft are loosely connected to each other.

[0061] For example, even if the moving axis of the lifting block deviates from the initially set position, resulting in a parallelism tolerance between the up-and-down movement of the upper frame used to cut the electrode sheet and the up-and-down movement of the lifting block, this change has little impact on the up-and-down movement of the upper frame. Therefore, the straightness of the up-and-down movement of the upper frame is guaranteed, thereby preventing changes in the gap and parallelism between the upper and lower cutters, which were precisely set in the initial stage.

[0062] An elastic member is installed in the recess of the lifting block, thereby allowing a certain degree of clearance between the lifting block and the connecting shaft. For example, a spring or rubber can be used as the elastic member.

[0063] Figure 4 This is a perspective view of a part of the power transmission unit used in electrode cutting equipment. Figure 5 This is a partial perspective view showing the power transmission unit for the electrode cutting equipment mounted on the main frame 600.

[0064] Reference Figure 4 Two connecting shafts, namely, the first connecting shaft 310 and the second connecting shaft 320, are connected to the upper frame 200, and the first connecting shaft 310 and the second connecting shaft 320 are spaced apart from each other.

[0065] A fixed frame 500 is provided on the first connecting shaft 310 and the second connecting shaft 320 and fixed to the lifting block 100, and an elastic member 400 is fixed on the upper part of the fixed frame 500 by a fixing screw 110 fastened to the lifting block 100.

[0066] In this structure, the pressing force and elastic force of the elastic member 400 relative to the fixed frame 500 are applied equally to the first connecting shaft 310 and the second connecting shaft 320.

[0067] The method for assembling a power transmission unit for an electrode cutting device according to the present invention includes the following steps: (a) preparing a lifting block to be mounted to a main frame; (b) fixing a connecting shaft to an upper frame; (c) fastening the upper frame with the fixed connecting shaft to the lifting block by sliding; (d) providing an elastic member on the upper part of the connecting shaft through a through hole in the lifting block; and (e) fastening a fixing screw to the through hole in the lifting block to fix the elastic member.

[0068] The connecting shaft is attached to the upper frame such that the engagement angle between the connecting shaft and the upper surface of the upper frame is a right angle within the allowable range of precise tolerance.

[0069] Furthermore, in step (c), the upper frame can be slidably fastened to the lifting block while a fixed frame is provided in the recess formed in the lifting block.

[0070] After sliding and tightening, the spring, which is an elastic member, can be inserted into the through hole of the lifting block, and the fixing screw can be tightened into the through hole of the lifting block to fix the spring.

[0071] The present invention will be described below with reference to the following embodiments. These embodiments are provided to facilitate a better understanding of the invention, but the scope of the invention is not limited thereto.

[0072] <Comparative Example>

[0073] like Figure 1 As shown in the electrode cutting device, the electrode sheet is cut using a power transmission unit for the electrode cutting device, which is configured to securely connect the connecting shaft to the lifting block via bolts. The connecting shaft is configured to connect the lifting block and the upper frame to each other.

[0074] Figure 6 The cut surface of the electrode sheet is shown in the figure.

[0075] <Example>

[0076] The electrode sheet is cut using the power transmission unit for the electrode cutting equipment according to the present invention. Figure 7 The cut surface of the electrode sheet is shown in the figure.

[0077] Reference Figure 6 and Figure 7 In the cut surface of the electrode sheet according to the comparative example, the electrode sheet 711 is bent and pushed downward, thereby generating burrs. The electrode mixture layer 712 breaks, thereby blowing out powder, and the cut surface of the electrode mixture layer is not smooth.

[0078] In contrast, in the cut surface of the electrode sheet according to the embodiment, the electrode sheet plate 811 is not bent, and the cut surface of the electrode mixture layer 812 is smooth.

[0079] When using the power transmission unit for electrode cutting equipment according to the present invention, as described above, the electrode sheet can be neatly cut to have a smooth cut surface and separation of the electrode mixture layer can be prevented.

[0080] Those skilled in the art will understand that, based on the above description, various applications and modifications are possible within the scope of this invention.

[0081] (Refer to the labeling explanation)

[0082] 10, 100: Lifting blocks

[0083] 15: Headless bolt

[0084] 21, 210: Upper cutter

[0085] 110: Fixing screws

[0086] 20, 200: Upper frame

[0087] 220: Upper cutter retainer

[0088] 25, 250: Lower cutter

[0089] 260: Lower Frame

[0090] 30, 300: Connecting shaft

[0091] 310: First connecting shaft

[0092] 320: Second connecting shaft

[0093] 400: Elastic member

[0094] 500: Fixed frame

[0095] 600: Main frame

[0096] 711, 811: Electrode plates

[0097] 712, 812: Electrode mixture layer.

[0098] Industrial applicability

[0099] As can be seen from the above description, the power transmission unit for the electrode cutting device according to the present invention is configured such that the upper frame and the lifting block mounted to the main frame to provide the power required for the up-and-down movement of the upper frame are fastened to each other with an elastic member provided between the upper frame and the lifting block, thereby loosely connecting the upper frame and the lifting block.

[0100] Therefore, even if parallelism tolerances occur between the lifting block and the upper frame when the lifting block and the upper frame move up and down, the straightness of the upper frame can still be guaranteed.

[0101] As the straightness of the upper frame is ensured as described above, fluctuations in the gap between the upper and lower cutters can be prevented during repeated cutting of the electrode sheet.

[0102] Therefore, the cut surface of the electrode sheet will not bend or produce burrs, which can prevent the separation of the electrode mixture layer and maintain a high cutting force uniformly.

[0103] In addition, it can reduce the calibration time required to maintain the parallelism between the upper and lower cutters, thereby improving productivity.

Claims

1. A power transmission unit for an electrode cutting apparatus, the power transmission unit comprising: a lifting block including a structure that is movably installed up and down to a main frame; an upper frame to which an upper cutter holder is installed, the upper cutter holder having an upper cutter configured to cut an electrode sheet fixed thereto; a connecting shaft configured to connect the lifting block and the upper frame to each other; and a resilient member located at an upper portion of the connecting shaft, wherein the resilient member is installed to allow a certain degree of clearance between the lifting block and the connecting shaft, wherein one end of the connecting shaft is inserted into a recess formed in the lifting block by sliding, and up and down movement of the one end of the connecting shaft is limited by the recess in the lifting block, and wherein the lifting block has a through hole that communicates with the recess in the lifting block from above, and the resilient member is disposed in the through hole and contacts the one end of the connecting shaft. 2.The power transmission unit according to claim 1, wherein the resilient member is a spring or rubber. 3.The power transmission unit according to claim 1, wherein the connecting shaft is inserted into and coupled to a recess formed in the upper frame. 4.The power transmission unit according to claim 1, wherein the recess in the lifting block is configured to accommodate the connecting shaft and the resilient member. 5.The power transmission unit according to claim 4, wherein the upper frame is fastened to the lifting block by sliding in a state in which the upper frame is coupled to the connecting shaft. 6.The power transmission unit according to claim 1, wherein the connecting shaft is loosely coupled to the lifting block via the resilient member located at a lower portion of a fixing screw coupled to the lifting block. 7.The power transmission unit according to claim 1, wherein the connecting shaft includes a first connecting shaft and a second connecting shaft, a fixing frame fixed to the lifting block is provided on the first connecting shaft and the second connecting shaft, and the resilient member is disposed at an upper portion of the fixing frame. 8.The power transmission unit according to claim 7, wherein a pressing force and an elastic force of the resilient member are equally applied to the first connecting shaft and the second connecting shaft with respect to the fixing frame. Even if parallelism tolerance occurs between up and down movement of the upper frame that performs cutting of the electrode sheet and up and down movement of the lifting block, straightness of the up and down movement of the upper frame is guaranteed.

9. The power transmission unit of claim 1, wherein, 10.A method of assembling the power transmission unit according to any one of claims 1 to 9, comprising the steps of: (a) preparing a lifting block installed to a main frame; (b) fixing a connecting shaft to an upper frame; (c) fastening the upper frame having the connecting shaft fixed thereto to the lifting block by sliding; (d) disposing a resilient member at an upper portion of the connecting shaft via a through hole of the lifting block; and (e) fastening a fixing screw to the through hole of the lifting block to fix the resilient member. In step (c), the upper frame is fastened to the lifting block by sliding in a state in which a fixing frame is disposed in a recess formed in the lifting block.

11. The method of claim 10, wherein, ​

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