Rolling groove die and rolling groove equipment

Abstract

The invention discloses a channeling die and channeling equipment. The channeling die comprises an outer die sleeve, an inner die sleeve and an inner die core which are sequentially nested around the central axis and can synchronously rotate, a power device of the channeling die drives the outer die sleeve, the outer die sleeve can drive the inner die sleeve and the inner die core to move, and the outer die sleeve is connected to the inner die sleeve through a first linkage limiting mechanism. The outer die sleeve and the inner die sleeve are connected to the inner die core through a first linkage limiting mechanism, so that the outer die sleeve and the inner die sleeve can synchronously and vertically move relative to the inner die core in the channeling process, the outer die sleeve and the inner die sleeve are connected to the inner die core through a second linkage limiting mechanism, and when the outer die sleeve and the inner die core vertically move relative to the inner die sleeve in the workpiece jointing and releasing process and the workpiece is released, the inner die core moves earlier than the inner die sleeve. According to the channeling mold, the inner mold core is pressed on the battery cell at the beginning of channeling and automatically ascends to be separated from the battery cell at the end of channeling, and the inner mold sleeve and the inner mold core do not make contact with or scrape the inner wall of a battery shell or the channeling position in the whole process, so that the abrasion of the mold is reduced.

Description

Technical Field

[0001] The present invention relates to a grooving die and a grooving device, and particularly to a grooving die and a grooving device for the field of battery processing. Background Art

[0002] In the production and manufacturing process of a battery (such as a cylindrical battery), the grooving process of the battery shell is a key process in battery production. The open end of the battery shell containing the battery core needs to be grooved by a grooving machine so as to facilitate subsequent shell sealing and battery packaging. In the existing grooving process, a hob is usually used to contact and rotate the battery shell. At the contact position between the two, the hob squeezes the outer peripheral surface of the battery shell, causing the shell to radially indent inward and undergo tensile deformation to form a circular groove on the battery shell.

[0003] When performing the grooving process, a die is required to fix and drive the battery to rotate. The existing die includes an upper die and a lower die. Among them, the battery is placed between the upper die and the lower die, the bottom end of the battery is placed in the lower die, and the upper die corresponds to the shape and size of the inner peripheral surface of the battery shell. The upper die is inserted into the battery shell through the open end of the battery shell and forms a tight fit with the inner peripheral surface of the battery shell, so that the battery shell is sleeved and fixed on the upper die. For example, for a cylindrical battery, the upper die can be cylindrical and the lower end can have a cylindrical boss. The inner peripheral surface of the battery shell is clamped on the outer peripheral surface of the cylindrical boss, and the end surface of the open end of the battery shell abuts against the shoulder of the boss.

[0004] For this technical solution, the inner peripheral surface of the battery shell bears the clamping force and frictional force. And during the grooving process, the hob feeds from one side of the battery, applies the extrusion force at the grooving position on the battery shell, and transfers it from the outer peripheral surface through the inner peripheral surface to the upper die. Since the battery shell bears the extrusion force of the hob on one side, the loading condition of the battery shell is similar to that of a cantilever beam, and a moment is formed between the grooving position and the open end of the battery shell. As a result, the battery shell generates displacement and deformation, the stress fluctuation and randomness at the grooving position are large, the load magnitude and direction cannot be precisely controlled, and the battery shell cannot be loaded stably during the entire grooving process. The shape of the circular groove itself and the surrounding area is irregular, resulting in a large difference between different battery individuals of the same-size battery shell, and the consistency of the mass-produced products is poor. Due to the random deformation and uneven and unstable loading at the grooving position, the end surface and the inner peripheral surface of the open end of the battery shell that are fixedly fitted with the upper die will also deform and be loaded unevenly and irregularly, making it difficult for the battery shell to be demolded, or even stuck to the upper die, resulting in wear of the die and reduction of its service life.

[0005] In addition, the battery housing generally undergoes plating (such as nickel plating) or coating treatment. Since multiple areas such as the grooving position, the open end, and the surrounding areas all experience the above-mentioned uneven deformation and loading, it is easy for the plating or coating or metal particles on the outer peripheral surface of the grooving position and the inner peripheral surface of the open end to fall off, thereby generating dust and metal fines. If the dust and fines fall inside the battery cell, they will contaminate the battery cell and cause a short circuit inside the battery cell, affecting the quality and safety of the battery.

[0006] Therefore, a technical solution that can at least partially solve the above-mentioned multiple problems is needed. SUMMARY OF THE INVENTION

[0007] In one aspect, the present invention discloses a grooving die, which includes an outer die sleeve, an inner die sleeve, and an inner die core that are sequentially nested around a central axis and can rotate synchronously. Among them, a power device of the grooving die drives the outer die sleeve, and the outer die sleeve can drive the inner die sleeve and the inner die core to move. The outer die sleeve is connected to the inner die sleeve through a first linkage limiting mechanism, so that the outer die sleeve and the inner die sleeve can move vertically synchronously relative to the inner die core during the grooving process. The outer die sleeve and the inner die sleeve are connected to the inner die core through a second linkage limiting mechanism, so that the outer die sleeve and the inner die core move vertically relative to the inner die sleeve during the process of engaging and releasing the workpiece, and when releasing the workpiece, the inner die core moves before the inner die sleeve.

[0008] According to an embodiment of the present invention, the first linkage limiting mechanism includes: an outer ring, sleeved on the outside of the outer die sleeve and close to the lower part of the outer die sleeve; a plurality of first height adjusting elements, connected between the upper flange of the outer die sleeve and the outer ring, and the length of the first height adjusting element itself can change; a plurality of first limiting rods, arranged on the outer peripheral surface of the inner die sleeve and extending radially outward; a plurality of first limiting grooves, penetratingly arranged in the lower part of the wall of the outer die sleeve and extending longitudinally. Among them, each first limiting rod passes through the corresponding first limiting groove and is connected to the outer ring, and the first limiting rod can move vertically in the first limiting groove.

[0009] According to an embodiment of the present invention, the second linkage limiting mechanism includes: a first groove, arranged on the upper inner wall of the outer die sleeve and extending longitudinally; a second height adjusting element, arranged between the first shoulder of the inner cavity of the inner die sleeve and the upper end surface of the inner die core inserted into the inner cavity, and the length of the second height adjusting element itself can change; a second limiting rod, arranged on the outer periphery of the inner die core and extending radially outward; a second limiting groove, penetratingly arranged in the middle part of the wall of the inner die sleeve and extending longitudinally; among them, the second limiting rod extends through the corresponding second limiting groove and enters the corresponding first groove, and the second limiting rod can move vertically in the second limiting groove.

[0010] According to an embodiment of the present invention, in the initial state of the rolling groove die, the first limiting rod is located at the lower end of the first limiting groove, and the second limiting rod is located at the upper end of the second limiting groove.

[0011] According to an embodiment of the present invention, in the initial state of the rolling groove die, the downward acting force exerted by the plurality of first height adjusting elements on the outer ring is greater than or equal to the upward acting force exerted by the second height adjusting element on the inner die sleeve.

[0012] According to an embodiment of the present invention, in the initial state of the rolling groove die, the upward acting force exerted by the plurality of first height adjusting elements on the outer die sleeve is greater than or equal to the downward acting force exerted by the second height adjusting element on the inner die core.

[0013] According to an embodiment of the present invention, the length of the first limiting groove is equal to the length of the second limiting groove.

[0014] According to an embodiment of the present invention, during the process of the rolling groove die engaging the workpiece, the inner die sleeve remains stationary, the outer die sleeve moves downward, so that the second limiting rod moves from the upper end of the second limiting groove to the lower end of the second limiting groove, and the first limiting groove moves downward, so that the upper end of the first limiting groove abuts against the first limiting rod.

[0015] According to an embodiment of the present invention, during the process of the rolling groove die engaging the workpiece, the distance between the outer die sleeve and the outer ring decreases, and the acting force of the plurality of first height adjusting elements becomes larger.

[0016] According to an embodiment of the present invention, during the process of the rolling groove die engaging the workpiece, the distance between the inner die sleeve and the inner die core increases, and the acting force of the second height adjusting element becomes smaller.

[0017] According to an embodiment of the present invention, during the process of the rolling groove die engaging the workpiece, after the second limiting rod moves to the lower end of the second limiting groove and remains stationary, the power device drives the outer die sleeve, the inner die sleeve and the inner die core to rotate synchronously to start the rolling groove process.

[0018] According to an embodiment of the present invention, during the rolling groove process, the outer die sleeve and the inner die sleeve move downward synchronously relative to the inner die core.

[0019] According to an embodiment of the present invention, after grooving by the grooving die, the outer die sleeve and the inner die core move upward relative to the inner die sleeve until the second limiting rod moves upward to the upper end of the second limiting groove, and the lower end of the first limiting groove abuts against the first limiting rod.

[0020] According to an embodiment of the present invention, the first height adjusting element and the second height adjusting element are compression springs.

[0021] According to an embodiment of the present invention, the first shoulder extends radially inward from the inner cavity of the inner die sleeve to form an inner side step, and the second height adjusting element is arranged between the first shoulder and the upper end face of the inner die core.

[0022] According to an embodiment of the present invention, a plurality of first jacks are arranged in the inner peripheral wall of the outer ring, and the first limiting rod is inserted into the corresponding first jack.

[0023] According to an embodiment of the present invention, the outer die sleeve includes a hollow outer die sleeve body, the upper flange protrudes radially outward from the upper end of the outer die sleeve body, the inner die sleeve is inserted into the outer die sleeve body, and the first height adjusting element is arranged between the upper flange and the outer ring.

[0024] According to an embodiment of the present invention, a plurality of first recesses are arranged in the upper end face of the outer ring, and the first height adjusting element is arranged in the corresponding first recess.

[0025] According to an embodiment of the present invention, the first groove extends upward to the upper flange and penetrates the upper flange.

[0026] On the other hand, the present invention discloses a grooving device, including the grooving die described in the first aspect and a bottom clamping mechanism.

[0027] According to the grooving die and device of the present invention, when processing a workpiece exemplified by a battery, the inner die core presses on the battery cell at the beginning of grooving and automatically rises away from the battery cell at the end of grooving, improving the degree of automation. And during the whole process, the inner die sleeve and the inner die core do not contact and scratch the inner peripheral surface and inner wall of the battery case or the grooving position, reducing the wear of the die and increasing the service life of the die.

[0028] The above grooving die and device are simple, with few components, low cost, easy to implement, and convenient to operate and have a high degree of automation. Description of the Drawings

[0029] Figure 1 It is a perspective view of the grooving die and the workpiece to be processed according to the present invention.

[0030] Figure 2 The Figure 1 cross-sectional view of the grooving die and the workpiece to be machined as shown, the cross-section shown passes through the center line of the grooving die and the second limiting rod of the second linkage limiting mechanism, and at the same time shows the internal structure at this cross-section of the grooving die and the workpiece to be machined.

[0031] Figure 3 The Figure 1 cross-sectional view of the grooving die as shown, the cross-section shown passes through the position just in front of the second limiting rod of the second linkage limiting mechanism.

[0032] Figure 4 The Figure 1 another cross-sectional view of the grooving die as shown, the cross-section shown cuts off Figure 1 the frontmost height adjusting element (i.e., the spring) in

[0033] Figure 5 The Figure 1 perspective view of the outer ring of the grooving die as shown.

[0034] Figure 6 The Figure 1 perspective view of the outer die sleeve of the grooving die as shown, showing the arrangement of the first limiting groove and multiple first air inlet holes.

[0035] Figure 7 is a cross-sectional view through Figure 6 the center line of the outer die sleeve of

[0036] Figure 8 The Figure 1 another perspective view of the outer die sleeve of the grooving die as shown, showing the arrangement of two first grooves from another angle.

[0037] Figure 9 is the perspective view when the inner die sleeve and the inner die core are assembled together.

[0038] Figure 10 The Figure 9 cross-sectional view of the inner die sleeve and the inner die core of

[0039] Figure 11 shows the connection between the two, the cross-section shown passes through the center lines of the inner die sleeve and the inner die core, the second limiting rod of the second linkage limiting mechanism, and a pair of second air inlet holes.

[0040] Figure 12 is the perspective view of the inner die core.

[0041] Figure 13 Perspective view of the grooving die and the workpiece to be machined engaging in grooving during the grooving process.

[0042] Figure 14 For Figure 13 Cross-sectional view of the grooving die and the workpiece to be machined engaging in grooving, showing the positional relationship of the various components of the grooving die. The shown section passes through the center line of the grooving die and a pair of second air inlet holes.

[0043] Figure 15 For Figure 14 Upper part of the cross-sectional view, showing a schematic diagram of the dust suction path during the grooving process.

[0044] Figure 16 For Figure 15 Enlarged view of region I, showing the positioning and clamping of the grooving die on the outer shell of the workpiece to be machined during the grooving process.

[0045] Reference numerals: 10 - grooving die; 11 - outer die sleeve; 110 - outer die sleeve body; 111 - upper end flange; 112 - first limiting groove; 113 - first air inlet hole; 114 - first groove; 12 - outer ring; 121 - outer ring body; 122 - first recess; 123 - first jack; 13 - first height adjusting element; 14 - inner die sleeve; 140 - inner die sleeve body; 141 - first limiting rod; 142 - second limiting groove; 143 - first shoulder; 144 - second air inlet hole; 1441 - first part; 1442 - second part; 1443 - intermediate part; 145 - second shoulder; 146 - step; 147 - inclined surface; 148 - annular groove; 149 - lower end section; 15 - inner die core; 150 - inner die core body; 151 - second limiting rod; 152 - third air inlet hole; 16 - second height adjusting element; 20 - battery; 21 - outer shell; 211 - chamfer; 22 - battery cell. Detailed description of the specific embodiment

[0046] Combined with the accompanying drawings of the specification, the preferred embodiments of the present invention will be further described in detail below. The following description is exemplary and not a limitation to the present invention. Any other similar situations also fall within the protection scope of the present invention.

[0047] In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more. It should also be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "vertical direction", "horizontal", "top", "bottom", "inner", "outer", "axial direction", "radial direction", "circumferential direction", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application.

[0048] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0049] The present invention provides a grooving device, which includes a grooving die, a positioning and clamping device, and a synchronous dust suction device. The grooving die of the present invention can quickly and efficiently clamp the workpiece and realize the automatic clamping and demoulding of the die. The positioning and clamping device of the present invention can conveniently position, clamp, and fix the workpiece shell, make the workpiece shell be uniformly and stably loaded during the grooving process, reduce the deformation of the workpiece shell, reduce the generation of dust and debris, and can realize easy and quick demoulding. The synchronous dust suction device of the present invention can efficiently and comprehensively remove the generated dust and debris synchronously during the grooving process to prevent them from entering the inner core of the workpiece.

[0050] The following takes the drawings as an example to describe the grooving device. The workpiece to be processed or the workpiece to be grooved shown is a cylindrical battery, but it is not limited thereto. The workpiece can be a product to be grooved other than the battery. The workpiece has a shell and an inner core. The battery as the workpiece can also be a battery of other shapes and types, and the concept of the present invention is equally applicable. Refer to Figure 1 and Figure 2 , the battery 20 as the workpiece includes a shell 21 and an electrode core 22. The electrode core 22 is installed in the shell 21. The shell is made of metal. Here, the steel shell is taken as an example to describe the battery shell. Of course, the shell can also be made of other metals, and a nickel layer is plated on the shell. As described above and as Figure 1As shown, the upper end of the outer shell is open, and a rolling groove is to be formed in the area near the upper end opening. The rolling groove device includes a rolling groove die, a hob, and a power device. The power device is connected to the rolling groove die and drives the rolling groove die to move, for example, move downward to engage and clamp the workpiece to be processed and rotate together, while the hob feeds towards the workpiece and extrudes the outer shell of the workpiece, thereby completing the rolling groove. The workpiece to be processed, such as a battery, is placed between the rolling groove die and the bottom clamping mechanism. The bottom end of the battery is placed in the accommodating cavity of the bottom clamping mechanism, and the open end of the battery is processed by the rolling groove die and the hob. After the rolling groove is completed, the inner die sleeve and the inner die core of the rolling groove die automatically retract and will not scrape against the rolling groove position. This article will focus on describing the rolling groove die. The power device, the hob, and the bottom clamping mechanism can adopt the solutions of the prior art and will not be elaborated here.

[0051] Referring to Figures 1 to 12 , the rolling groove die 10 and the workpiece are shown. In the figure, the workpiece is a battery 20. The power device, the hob, and the bottom clamping mechanism are omitted in the figure. The power device can be a drive shaft, which is connected to the rolling groove die 10 and drives the rolling groove die 10 to move. Specifically, the movement of the rolling groove die 10 includes the downward movement, the positioning and clamping movement of the workpiece, the rotational movement, and the releasing movement shown in the figure. As Figures 1 - 2 shown, the rolling groove die 10 includes an outer die sleeve 11, an inner die sleeve 14, and an inner die core 15 that are coaxially nested around the central axis (or simply referred to as the center line) and can rotate synchronously. The outer die sleeve 11 is connected to the power device, and the power device drives the outer die sleeve 11 to move vertically along the central axis and rotate around the central axis. Furthermore, the outer die sleeve 11 drives the inner die sleeve 14 and the inner die core 15 to move vertically and rotate to complete the rolling groove. When the power device retracts the outer die sleeve after the rolling groove is completed, the inner die sleeve and the inner die core are automatically retracted by the outer die sleeve, thereby realizing the overall movement of the rolling groove die 10. In this article, the vertical direction can also be referred to as the direction along the central axis, or the up-and-down direction, or the longitudinal direction. Therefore, the vertical movement / motion can also be referred to as the movement / motion along the central axis, or the up-and-down movement / motion, or the longitudinal motion.

[0052] The movement between the outer die sleeve 11, the inner die sleeve 14, and the inner die core 15 of the above rolling groove die 10 is realized through the first linkage limiting mechanism and the second linkage limiting mechanism. The first linkage limiting mechanism and / or the second linkage limiting mechanism can not only limit the extreme positions of the movement between the outer die sleeve 11, the inner die sleeve 14, and the inner die core 15, but also drive the abutted component to move when abutting after reaching the extreme position of the movement, thereby realizing linkage.

[0053] Specifically, the outer mold sleeve 11 and the inner mold sleeve 14 are connected by a first linkage limiting mechanism. The first linkage limiting mechanism includes: at least two first height adjusting elements 13, an outer ring 12, at least two first limiting rods 141, and at least two first limiting grooves 112. Among them, at least two first limiting rods 141 (shown as four in the figure) are circumferentially and evenly spaced on the lower outer surface of the inner mold sleeve 14 and extend radially outward; at least two longitudinal limiting grooves 112 (shown as four in the figure) are circumferentially and evenly spaced on the lower part of the outer mold sleeve 11, and at least two first insertion holes 123 (shown as four in the figure) are circumferentially and evenly spaced on the outer ring 12. The first limiting rods 141 of the inner mold sleeve 14 pass through the first limiting grooves 112 of the outer mold sleeve 11 and are inserted into the first insertion holes 123 of the outer ring 12, and the first limiting rods 141 can move up and down in the first limiting grooves 112. The upper ends of at least two first height adjusting elements 13 (shown as four in the figure) are connected to the upper flange 111 of the outer mold sleeve 11, and the lower ends are connected to the first concave portions 122 on the upper end surface of the outer ring 12. The first height adjusting element 13 is shown as a spring in the figure. Through the height change of the first height adjusting element 13 and the moving position of the first limiting rod 141 in the first limiting groove 112, the relative movement between the two at the intermediate position and the abutment of the first limiting rod and the end of the first limiting groove at the limit position of the first limiting groove are realized to achieve linkage.

[0054] The outer mold sleeve 11, the inner mold sleeve 14 and the inner mold core 15 are connected by a second linkage limiting mechanism. The second linkage limiting mechanism includes a second limiting rod 151, a second limiting groove 142, a first groove 114 and a second height adjusting element 16. Among them, the inner mold sleeve 14 is formed with a stepped inner cavity, the diameter of the upper inner cavity is smaller than that of the lower inner cavity, so as to form an inner shoulder (i.e., the first shoulder) 143. The inner mold core 15 is coaxially inserted into the lower inner cavity. The upper end of the second height adjusting element 16 arranged in the lower inner cavity abuts against the shoulder 143 and the lower end abuts against the upper end face of the inner mold core 15. A longitudinal second limiting groove 142 is arranged at a roughly middle position of the inner mold sleeve 14. The second limiting rod 151 extends radially from the inner mold core 15, passes through the second limiting groove 142 and slightly protrudes from the outer surface of the inner mold sleeve 14 until it extends into the longitudinal first groove 114 formed in the upper inner wall of the outer mold sleeve 15. Thus, the second limiting rod 151 can move up and down. The first height adjusting element 13 and the second height adjusting element 16 are elements with variable lengths, and corresponding acting forces are generated therefrom. Among them, the acting force of the first height adjusting element 13 is applied to the outer mold sleeve 11, the outer ring 12, the first limiting rod 141 and the inner mold sleeve 14, so that the first limiting rod 141 and the first limiting groove 112 move up and down relative to each other; the acting force of the second height adjusting element 16 is applied to the outer mold sleeve 11, the inner mold core 15 and the second limiting rod 151, so that the second limiting rod 151 moves up and down in the second limiting groove 142. The lengths of the first height adjusting element 13 and the second height adjusting element 16 can change by themselves to generate acting forces. They can be, for example, springs or fluid cylinders or slider devices. The fluid cylinder includes, for example, a hydraulic cylinder or a pneumatic cylinder. The length change of the spring includes becoming shorter or longer when being compressed or stretched, thus generating a pressure or a tensile force due to the deformation relative to the initial length. The hydraulic cylinder or the pneumatic cylinder includes a cylinder body, a fluid medium (such as oil or gas) accommodated in the cylinder body and a piston movable in the cylinder body. As the length of the piston extending out of the cylinder body changes, corresponding thrusts or tensile forces of different magnitudes are generated.

[0055] Among them, the first linkage limiting mechanism including the outer ring 12, the first height adjusting element 13, the first limiting rod 141 and the first limiting groove 112 can realize the vertical synchronous movement of the outer die sleeve 11 and the inner die sleeve 14 relative to the inner die core 15 during the grooving process. The condition for starting this synchronous movement is that the first limiting groove 112 moves vertically relative to the first limiting rod 141, so that the first limiting rod 141 contacts the upper end of the first limiting groove 112. The second linkage limiting mechanism including the second height adjusting element 16, the second limiting rod 151, the second limiting groove 142 and the first groove 114 can realize the vertical movement of the outer die sleeve 11 and the inner die core 15 relative to the inner die sleeve 14 during the process of engaging or clamping and releasing the workpiece. The movement range of this movement is determined by the length of the second limiting groove 142. Specifically, during the process of engaging or clamping the workpiece, the inner die sleeve 14 abuts against the workpiece and remains stationary, and the outer die sleeve 11 and the inner die core 15 move synchronously downward vertically relative to the inner die sleeve 14. During the process of releasing the workpiece after the grooving is completed, the inner die sleeve 14 abuts against the workpiece, the outer die sleeve 11 first moves upward a certain distance by itself, and then the first groove 114 contacts the second limiting rod 151 of the inner die core 15, thereby driving the second limiting rod 151 and the inner die core 15 to move upward until the second limiting rod 151 abuts against the upper end of the second limiting groove 142. In addition, after the workpiece is clamped, the outer die sleeve 11, the inner die sleeve 14 and the inner die core 15 can be driven by a power device to rotate synchronously with the clamped workpiece during the grooving process, and from the completion of the grooving to the release of the workpiece, the outer die sleeve 11, the inner die sleeve 14 and the inner die core 15 can also rotate synchronously.

[0056] The following will describe each component in detail with reference to the drawings.

[0057] As Figures 1 - 4As shown in FIGS. 6 and 8, the outer mold sleeve 11 includes a cylindrical outer mold sleeve body 110 and an upper flange 111 that radially protrudes outward from the upper end of the body 110. Similar to a common flange structure, the upper flange 111 is annular, and a plurality of fastening holes are provided on the annular end surface of the upper flange for inserting fasteners to fixedly connect to the power device. Near the lower end of the body 110, a plurality of first air inlet holes 113 are arranged circumferentially around the outer peripheral surface of the body. The first air inlet holes are through holes that penetrate the wall of the body, for allowing air flow to enter the interior of the body from the outside through these first air inlet holes. The number of the first air inlet holes 113 is not limited and can be flexibly set according to specific applications, and these first air inlet holes 113 can be arranged evenly or unevenly around the outer peripheral surface of the body. In addition, at a position above these first air inlet holes 113, a plurality of first limiting grooves 112 that penetrate the wall thickness are provided in the wall of the body, that is, the plurality of first limiting grooves 112 are provided in the lower part of the wall of the outer mold sleeve 11 and extend longitudinally. The first limiting grooves are oblong and are used to receive the first limiting rods 141 described below. In the figure, the number of the first limiting grooves 112 is shown as four, but it is not limited thereto, and a larger or smaller number (such as 2, 3, 5, 6, and more) of first limiting grooves can be set, and these first limiting grooves can be arranged evenly or unevenly in the wall of the body. In addition, a plurality of first grooves 114 that extend longitudinally are provided in the inner wall of the upper part of the body for receiving the second limiting rods 151 described below. The first grooves are located above the first air inlet holes 113 and are spaced apart from the first limiting grooves 112 and the first air inlet holes 113. In the figure, a pair of first grooves 114 are symmetrically arranged in the inner wall of the body 110 with respect to the central axis of the outer mold sleeve 11, but this is only an example and is not restrictive. Those skilled in the art can set one first groove or 3, 4, or more first grooves. The first grooves 114 extend upward from a position above the first air inlet holes 113 and penetrate through the upper flange 111 to lead to the outside, so as to facilitate the assembly of the inner mold sleeve 14 and the second limiting rods 151 into the outer mold sleeve 11 along the first grooves 114. The second limiting rods 151 and the first limiting rods 141 described below can be any long rod-shaped members, such as pins or other long-shaped members.

[0058] As Figures 2 - 3As shown in FIGS. 7, 9-11, the inner mold sleeve 14 includes a cylindrical inner mold sleeve body 140, and the outer peripheral dimension of the inner mold sleeve body 140 is slightly smaller than or substantially equal to the inner peripheral dimension of the outer mold sleeve 11. For example, the outer diameter of the inner mold sleeve body 140 is slightly smaller than or substantially equal to the inner diameter of the outer mold sleeve 11, so that the inner mold sleeve 14 can move within the outer mold sleeve 11. A plurality of first limiting rods 141 extending radially outward are provided on the outer peripheral surface of the inner mold sleeve body 140. These first limiting rods 141 pass through the first limiting grooves 112 of the outer mold sleeve 11 and are inserted into the first insertion holes 123 of the outer ring 12 described below. The first limiting grooves 112 and the first limiting rods 141 have the same number and arrangement, that is, the first limiting grooves 112 and the first limiting rods 141 correspond one by one; alternatively, the first limiting grooves 112 can be redundantly provided, that is, the number of the first limiting grooves 112 is more than that of the first limiting rods 141, so that the first limiting rods 141 can be selectively inserted into the corresponding first limiting grooves 112. The length of the first limiting groove 112 is greater than the outer peripheral dimension (e.g., outer diameter) of the first limiting rod 141, and the width can be equal to or greater than the outer peripheral dimension of the first limiting rod 141, so that the first limiting rod 141 can freely move along the length direction within the first limiting groove 112.

[0059] Especially as Figure 9As shown, a second limiting groove 142 penetrating the wall thickness and extending in the longitudinal direction is provided in the wall of the inner mold sleeve body 140, that is, the second limiting groove 142 is provided through the middle of the wall of the inner mold sleeve 14 and extends longitudinally. Similar to the first limiting groove 112, the second limiting groove 142 is oblong and is used to receive a second limiting rod 151 described below. The figure shows that the number of the second limiting grooves 142 is two and they are symmetrically arranged with respect to the central axis of the inner mold sleeve body 140, but it is not limited thereto. Other numbers of the second limiting grooves 142 can be provided, and these second limiting grooves 142 can be arranged evenly or unevenly in the wall of the body. It should be noted that since the second limiting rod 151 needs to pass through the second limiting groove 142 and be inserted into the first groove 114 of the outer mold sleeve 11, the second limiting groove 142 and the first groove 114 have the same number and arrangement, that is, the second limiting groove 142 and the first groove 114 correspond one by one to facilitate the insertion of the second limiting rod 151; or one or both of the second limiting groove 142 and the first groove 114 can be redundantly provided, that is, their number is more than that of the second limiting rod 151, so that the second limiting rod 151 can be selectively inserted into the corresponding second limiting groove 142 and the first groove 114. Moreover, the length of the second limiting groove 142 is greater than the outer dimension (for example, the outer diameter) of the second limiting rod 151, and the width can be equal to or greater than the outer dimension of the second limiting rod 151, so that the second limiting rod 151 can move freely along the length direction within the second limiting groove 142. The second limiting groove 142 has the same length as the first limiting groove 112, so that the movement of the inner mold core is seamlessly connected with the movement of the outer mold sleeve and the inner mold sleeve without generating movement interference between these components, which will be described below.

[0060] In addition, at a position above the second limiting groove 142, the radial dimension of the inner peripheral wall or the inner cavity of the inner mold sleeve body 140 decreases radially inward to form an inner step, and the end face of the step forms a first shoulder 143 for placing the second height adjusting element 16 described below. At a position below the second limiting groove 142, an annular step 146 is formed on the lower end section 149 of the inner mold sleeve body 140, and the outer peripheral surface adjacent to the annular step 146 is recessed radially inward to form an annular groove 148. In the direction from the annular step 146 to the bottom end of the inner mold sleeve body 140, an annular second shoulder 145 is provided opposite to the annular step 146. The distance that the second shoulder 145 is recessed radially inward from the outer peripheral surface of the lower end section 149 of the inner mold sleeve body 140 is less than the distance that the annular step 146 is recessed radially inward, such that the second shoulder 145 is smaller than the annular step 146. As described below, the second shoulder 145 is used to abut against the end face of the open end of the battery case 21 during the rolling groove processing. Therefore, the width of the second shoulder 145 is substantially equal to the wall thickness of the case, and the inner diameter of the second shoulder 145 is smaller than the inner diameter of the battery case, and the outer diameter of the second shoulder 145 is equal to the outer diameter of the battery case. Thus, when the second shoulder 145 abuts against the end face of the battery case, there is a gap between the inner peripheral wall of the battery case and the second shoulder 145 and the inclined surface 147, and the inner peripheral dimension (inner diameter) of the outer mold sleeve is equal to the outer diameter of the second shoulder 145. When the bottom end of the outer mold sleeve moves to below the second shoulder 145, the battery case is clamped by the outer mold sleeve 11.

[0061] A frustum cone or an inclined surface 147 is formed from the second shoulder 145 to the bottom end of the inner mold sleeve body 140. As Figure 11 shown in the cross-sectional view, the second shoulder 145 tapers to the bottom end of the inner mold sleeve body 140 through the inclined surface 147. In other words, the lower end section 149 includes an annular step 146, a second shoulder 145, the outer peripheral surface between the annular step 146 and the second shoulder 145, and the inclined surface 147. Refer to Figures 9 to 11 , at the lower end section 149 of the inner mold sleeve body 140, at the annular step 146, a plurality of second air inlet holes 144 are formed in the wall of the inner mold sleeve body 140 in the circumferential direction. Each second air inlet hole 144 penetrates downward from the annular step 146 to the bottom end of the inner mold sleeve body 140 in the vertical direction, such that the second air inlet holes 144 are through holes, respectively penetrating the annular step 146, the section of the inner mold sleeve body between the annular step 146 and the second shoulder 145, and the inclined surface 147, without penetrating the second shoulder 145, that is, the second air inlet holes 144 are located between the second shoulder 145 and the inner wall of the inner mold sleeve body 140 in the radial direction.

[0062] Refer to Figures 9 to 11, it shows that the second air inlet hole 144 extends vertically downward from the outer peripheral surface in the annular groove 148 at the annular step 146 through the annular step 146 and the inclined surface 147 and penetrates through the bottom end of the inner mold sleeve body 140. The second air inlet hole 144 includes a first part 1441, a second part 1442, and an intermediate part 1443 located between these two parts. The intermediate part 1442 is completely located in the wall of the inner mold sleeve body 140 to form a complete hole shape, while the first part 1441 and the second part 1442 are incomplete hole shapes. The first part 1441 is located in the outer peripheral surface that radially indents inward from the annular step 146 in the annular groove 148. Therefore, the first part 1441 also radially indents inward into the outer peripheral surface, and the first part 1441 is open and exposed in the outer peripheral surface; the second part 1442 is the part that penetrates the inclined surface 147. Due to the conical shape of the inclined surface 147, the second part 1442 is more open and has a larger communication opening and area with the surrounding environment, so that the air flow can flow from the inclined surface 147 in multiple directions to a larger surrounding space. The setting of the first part 1441 can play a role in guiding the air flow. As described below, when the air flow flows horizontally towards the second air inlet hole 144, the air flow is first blown into the annular groove 148. Therefore, the first part 1441 in the annular groove 148 receives a part of the air flow and deflects the air flow from the horizontal direction to the vertical direction, and then vertically flows downward along the intermediate part 1443. When the air flow reaches the second part 1442, since the second part 1442 leads to the outside from the inclined surface 147, part of the air flow continues to flow vertically downward, while the other part obliquely flows to the side from the opening on the inclined surface 147. Thus, the second part 1442, similar to the first part 1441, also plays a role in guiding the air flow, such as deflecting the air flow.

[0063] The inner mold core 15 is nested in the inner mold sleeve 14 and moves up and down in the inner mold sleeve 14 and includes an inner mold core body 150. The inner mold core body 150 can be cylindrical and the outer peripheral dimension (such as the outer diameter) is smaller than the inner peripheral dimension (such as the inner diameter) of the inner mold sleeve 14 to facilitate the up and down movement of the inner mold core 15 in the inner mold sleeve 14. See Figures 10 to 12, a second limiting rod 151 extending horizontally or radially outward is provided at the upper end of the inner mold core body 150. Two holes can be provided in the outer peripheral wall at the upper end of the inner mold core body 150. These two holes are symmetric with respect to the central axis of the inner mold core body 150 along the diameter of the inner mold core body 150. Thus, the second limiting rod 151 is inserted into these two holes and both ends of the second limiting rod 151 are exposed outside the outer peripheral surface of the inner mold core body 150; alternatively, the above two holes may not be provided, but two second limiting rods 151 extending radially outward and symmetrically arranged in the diameter direction may be directly provided on the outer peripheral surface of the inner mold core body 150, as long as two ends protrude outside the outer peripheral surface of the inner mold core body 150, that is, the second limiting rod 151 may be provided with only 1, 2, 3 or more, and the second limiting rod 151 is placed in the corresponding first groove 114. The second limiting rod 151 is inserted into the second limiting groove 142 and moves up and down along the second limiting groove, thereby driving the inner mold core 15 to move up and down in the inner mold sleeve 14.

[0064] See Figure 10 , the inner mold core 15 is nested in the inner mold sleeve 14, and a second height adjusting element 16 is placed between its top end and the first shoulder 143. As described above, the second height adjusting element may be a spring (such as a compression spring) or a fluid cylinder (such as a hydraulic cylinder or a pneumatic cylinder). In this article, the compression spring is taken as an example to describe the second height adjusting element 16 and the first height adjusting element 13, but the description also applies to the fluid cylinder and the slider device, which will not be elaborated here. The second height adjusting element can push the top end of the inner mold core 15 downward in the compressed state. Since the second limiting rod 151 is inserted into the second limiting groove 142, the second limiting rod 151 can move in the second limiting groove 142 and the movement range is limited by the length of the second limiting groove 142, that is, the inner mold core 15 can be pushed by the second height adjusting element 16 to move from the upper end of the second limiting groove 142 to the lower end. When the second limiting rod 151 moves from the lower end of the second limiting groove 142 to the upper end, the second height adjusting element 16 is compressed to the initial state. It should be noted that the second height adjusting element 16 applies the same force to both the inner mold sleeve 14 and the inner mold core 15, that is, an upward force is applied to the inner mold sleeve 14 and a downward force is applied to the inner mold core 15.

[0065] A plurality of third air inlets 152 are provided on the outer peripheral wall of the lower end of the inner mold core 15 in the circumferential direction. The third air inlets 152 are spaced apart from the bottom end of the inner mold core 15 and are used to introduce air flow into the internal space of the inner mold core 15. The bottom end of the inner mold core 15 is used to press against the battery cell 22, so that during the grooving process, when the battery 20 rotates, the cell is firmly held in the outer shell 21 to prevent displacement. The number of the third air inlets is not limited and can be arranged evenly or unevenly. Preferably, the third air inlets are set to have a larger length in the circumferential direction to facilitate increasing the area of the air flow channel and quickly guiding the air flow into the internal space of the inner mold core 15.

[0066] The grooving die 10 further includes an outer ring 12. The outer ring is sleeved outside the outer mold sleeve body 110 of the outer mold sleeve, spaced apart from the outer mold sleeve body and close to the lower end portion of the outer mold sleeve 11. The outer ring 12 includes an annular outer ring body 121. The outer ring body 121 includes an annular upper end face, an annular lower end face and an outer peripheral wall. A plurality of first recesses 122 are provided on the upper end face. In the figure, 4 first recesses are shown to be evenly arranged in the circumferential direction on the upper end face, but this is only an example. The first recesses can have other more or fewer numbers (such as 2, 3, 5 and more), and can be arranged evenly or unevenly on the outer ring. The shape of the first recesses is also not limited and can have various regular and irregular shapes. The first recesses are used to receive the first height adjusting elements 13. The first height adjusting elements 13 can be springs, such as compression springs. The number and arrangement of the first height adjusting elements correspond to the first recesses. As Figures 1 to 4 shown, the first height adjusting elements 13 are arranged between the first recesses and the upper flange 111 of the outer mold sleeve to connect the outer ring to the outer mold sleeve 11. A plurality of fastening holes are also provided in the first recesses, and these fastening holes correspond to the fastening holes on the annular end face of the upper flange 11. Thus, fasteners (such as bolts) pass through the fastening holes in the first recesses 122, the first height adjusting elements 13 and the fastening holes of the upper flange 11 to connect the outer mold sleeve 11 to a power device, such as a drive shaft. It should be noted that the downward pressure of the plurality of first height adjusting elements 13 on the outer ring is greater than or equal to the upward pressure of the second height adjusting elements 16 on the inner mold sleeve, so that the forces on the outer ring 12, the first limiting rod 141 and the inner mold sleeve are balanced in the vertical direction or the downward force is greater than the upward force, so as to keep them in a balanced stress state or tend to be downward and be maintained in the initial state; similarly, the upward pressure exerted by the plurality of first height adjusting elements 13 on the upper flange 111 of the outer mold sleeve 11 is also greater than or equal to the downward pressure exerted by the second height adjusting elements 16 on the second limiting rod 151 and the first groove 114. Therefore, the outer mold sleeve 11 and the inner mold core 15 are kept in a balanced stress state or the upward force is greater than the downward force and tend to be upward and be maintained in the initial state.

[0067] In addition, a plurality of first jacks 123 penetrating the wall thickness are provided in the inner peripheral wall of the outer ring 12. These first jacks 123 are horizontally oriented and are used to insert the first limiting rods 141 of the inner mold sleeve 14. The first limiting rods 141 pass through the first limiting grooves 112 of the outer mold sleeve 11 and are inserted into the first jacks 123. Therefore, the first jacks 123, the first limiting grooves 112, and the first limiting rods 141 have the same number and arrangement, and they correspond to each other one by one; alternatively, the first jacks 123 can also be redundantly designed so that the first limiting rods 141 can be selectively inserted into the corresponding first jacks 123. The first jacks 123 can also be set as blind holes as long as it is ensured that the first limiting rods 141 can be inserted without interference.

[0068] Figures 1 to 12 The initial state of the grooving die 10 before grooving is described. The battery 20 is located below the grooving die 10 and is spaced apart from the grooving die 10 by a certain distance. At this time, the inner mold core 15 is nested in the inner mold sleeve 14, and the second height adjusting element 16 is located between the first shoulder 143 and the top end of the inner mold core 15 and is in a compressed state. The second height adjusting element 16 exerts an upward force on the inner mold sleeve 14, the first limiting rods 141, and the outer ring 12, and exerts a downward force on the inner mold core 15. The second limiting rods 151 are inserted into a pair of second limiting grooves 142 and are at the upper end positions of the second limiting grooves 142, and both ends of the second limiting rods 151 are inserted into and rest on the bottoms of a pair of first grooves 114 of the outer mold sleeve 11. The bottom end of the inner mold core 15 is flush with the bottom end of the inner mold sleeve 14. The inner mold sleeve 14 is nested in the outer mold sleeve 11. The first limiting rods 141 are inserted into the first limiting grooves 112 and are at the lower end positions of the first limiting grooves 112, and the ends of the first limiting rods 141 are inserted into the first jacks 123 of the outer ring 12. The outer ring 12 is connected to the outer mold sleeve 11 through the first height adjusting element 13. The first height adjusting element 13 exerts a downward force on the outer ring 12, and thus on the first limiting rods 141 and the inner mold sleeve 14. The downward force is the same as the upward force exerted by the second height adjusting element 16. The outer mold sleeve 11 is fixedly connected to the power device through fasteners. The first air inlet hole 113, the second air inlet hole 144, and the third air inlet hole 152 are not aligned with each other. The first air inlet hole 113 is located above the second air inlet hole 144, and the third air inlet hole 152 is located in the internal space of the inner mold sleeve body 140 and is separated from the second air inlet hole 144.

[0069] In this state, that is, before the outer die sleeve 11 moves downward, since the second height adjusting element 16 is initially in a compressed state, the second height adjusting element 16 presses the inner die core 15. The second limiting rod 151 of the inner die core 15 is located at the upper end of the second limiting groove 142. Therefore, the inner die core 15 tends to be pressed downward by the second height adjusting element 16, driving the second limiting rod 151 to move downward in the second limiting groove 142. However, both ends of the second limiting rod 151 rest in the first groove 114 of the outer die sleeve 11, and the first groove 114 receives an upward force applied to the outer die sleeve 11 by the first height adjusting element 13. As described above, the acting force of the first height adjusting element 13 is greater than or equal to the acting force of the second height adjusting element 16. Therefore, the second limiting rod 151 remains fixed at the upper end of the second limiting groove 142, and the second limiting rod 151 and the inner die core 15 remain stationary. And at this time, the first limiting rod 141 of the inner die sleeve 14 passes through the first limiting groove 112 and inserts into the first jack 123 of the outer ring. The pressure applied by the first height adjusting element 13 to the outer ring 12, the first limiting rod 141, and the inner die sleeve 14 is greater than or equal to the reverse force applied by the second height adjusting element 16. Therefore, they are in a force balance state or are held downward by a larger downward force, and the first limiting rod 141 remains stationary at the lower end of the first limiting groove 112.

[0070] It should be noted that in Figures 1 to 12The initial state of the grooving die 10 shown, the vertical distance between the second air inlet hole 144 of the inner die sleeve 14 and the first air inlet hole 113 of the outer die sleeve 11 is equal to the lengths of the first limiting groove 112 and the second limiting groove 142. Specifically, the vertical distance between the first part 1441 (or the annular groove 148) of the second air inlet hole 144 and the first air inlet hole 113 is equal to the lengths of the first limiting groove 112 and the second limiting groove 142. Such a setting makes that when the outer die sleeve 11 drives the inner die core 15 to move downward by a distance equal to the length of the second limiting groove 142, the first limiting groove 112 of the outer die sleeve 11 also moves downward by the same distance. At this time, the first air inlet hole 113 is aligned with the first part 1441 (or the annular groove 148) of the second air inlet hole 144, that is, each first air inlet hole 113 corresponds to each first part 1441 of each second air inlet hole 144 one by one. Thus, the air flow can directly blow from the first air inlet hole 113 to the corresponding first part 1441 and then enter the corresponding second air inlet hole 144. In addition, there is no specific limitation on the positional relationship between the first limiting groove 112 and the second limiting groove 142 in the vertical direction, that is, there is no specific numerical limitation on the distance between them. For example, the first limiting groove 112 can be located above the second limiting groove 142, and the distance between them only needs to meet the following condition: when the first limiting rod 141 is located at the lower end of the first limiting groove 112 and the second limiting rod 151 is located at the upper end of the second limiting groove 142, the upward force applied to the inner die sleeve 14 by the second height adjusting element 16 is less than or equal to the downward force applied by the first height adjusting element 13.

[0071] Figures 13 to 16 Another state diagram of the grooving die and the battery during grooving is shown. When starting the grooving process, the power device moves downward towards the battery 20, and then drives the grooving die 10 to move downward. Since the power device is fixedly connected to the outer die sleeve 11, therefore, the power device directly drives the outer die sleeve 11, that is, the movements of the outer die sleeve 11 and the power device are always synchronous. The movement of the grooving die 10 is divided into a clamping movement, a rotational movement, and a releasing movement. The clamping movement is that the grooving die 10 moves downward towards the battery and clamps the battery housing; the rotational movement is that after the battery housing is clamped, when the battery is driven to rotate by an external workpiece, the grooving die 10 is driven and rotates synchronously with the battery housing because it presses the battery housing, and then the hob rolls an annular groove on the battery housing; the releasing movement is that after the grooving is completed, the hob separates from the battery, and the grooving die 10 releases the battery and moves upward away from the battery.

[0072] During the clamping movement, the outer mold sleeve 11 moves synchronously with the inner mold core 15, while the inner mold sleeve 14 remains stationary; during the rotational movement, the outer mold sleeve 11 moves synchronously with the inner mold sleeve 14, the inner mold core 15, and the outer ring 12; during the release movement, the outer mold sleeve 11 and the inner mold core 15 move upward relative to the inner mold sleeve 14, while the inner mold sleeve 14 remains on the battery housing. When the inner mold core 15 moves to the initial state position in the inner mold sleeve 14, the outer mold sleeve 11, the outer ring 12, the inner mold sleeve 14, and the inner mold core 15 move upward as a whole to disengage from the contact with the battery. With the start of the clamping movement, the power device moves the rolling groove mold 10 downward as a whole to the battery, and the second shoulder 145 of the inner mold sleeve 14 abuts against the end face of the battery housing 21. Therefore, the inner mold sleeve 14, the first limiting rod 141, and the outer ring 12 are stopped from moving downward. At this time, the inclined surface 147 of the inner mold sleeve 14 extends into the battery housing, but is spaced apart from the battery cell 22; at the same time, since the bottom end of the inner mold core 15 is flush with the bottom end of the inner mold sleeve 14, a part of the inner mold core 15 also extends into the battery housing. The power device drives the outer mold sleeve 11 to move downward, and the first groove 114 of the outer mold sleeve 11 also moves downward accordingly. Since the second height adjustment element 16 presses the inner mold core 15 and then presses the second limiting rod 151, the second limiting rod 151 and the inner mold core 15 move downward with the downward movement of the first groove 114. The second limiting rod 151 moves downward along the second limiting groove 142 from the upper end to the lower end, and the bottom end of the inner mold core 15 moves downward from the position flush with the bottom end of the inner mold sleeve 14 and extends downward from the inner mold sleeve 14 to approach the battery cell 22. When the second limiting rod 151 moves downward to the lower end of the second limiting groove 142, the bottom end of the inner mold core 15 abuts against the battery cell 22 to press the battery cell 22 tightly to prevent the battery cell 22 from shifting during the rotation of the battery.

[0073] During this process, as the inner mold core 15 moves downward, the compressive deformation of the second height adjustment element 16 becomes smaller, and thus the upward force exerted on the inner mold sleeve 14 through the second shoulder 145 decreases. At the same time, as the outer mold sleeve 11 moves downward, the distance between the outer mold sleeve 11 and the outer ring 12 decreases, and the first height adjustment element 13 is further compressed, thereby increasing the downward force exerted on the outer ring 12. Therefore, the downward force received by the inner mold sleeve 14 is greater than the upward force exerted by the second height adjustment element 16, so the inner mold sleeve 14 does not move upward but abuts more closely against the end face of the battery housing 21. Since the length of the first limiting groove 112 is equal to the length of the second limiting groove 142 and is equal to the vertical distance between the second air inlet hole 144 and the first air inlet hole 113 of the outer mold sleeve 11, when the bottom end of the inner mold core 15 abuts against the battery cell 22, the first air inlet hole 113 moves downward to be aligned with the first part 1441 of the second air inlet hole 144 one by one, and the third air inlet hole 152 of the inner mold core 15 also extends from the inner mold sleeve 14 to the position radially inside and below the second air inlet hole 144, so that an air flow path from the first air inlet hole 113 to the second air inlet hole 144 and then to the third air inlet hole 152 can be formed. The third air inlet hole 152 guides the air flow into the internal spaces of the inner mold core 15 and the inner mold sleeve 14, and the upper end opening of the inner mold sleeve 14 leads to a power device and an external suction device, such as a negative pressure device. Therefore, with reference to the internal spaces of the inner mold core 15 and the inner mold sleeve 14, the inner mold core 15 and the inner mold sleeve 14 also include air outlet holes (for example, the upper end opening of the inner mold core 15 and the upper end opening of the inner mold sleeve 14). The above-mentioned air inlet holes guide the air flow into the internal spaces of the inner mold core 15 and the inner mold sleeve 14, and these air outlet holes are to guide the air flow from the internal spaces of the inner mold core 15 and the inner mold sleeve 14 to the outside. These air outlet holes form a loop with the above-mentioned air inlet holes to connect the air flow channels outside and inside the housing.

[0074] At the same time, as the distance that the outer mold sleeve 11 moves downward is equal to the length of the first limiting groove 112, the upper end of the first limiting groove 112 abuts against the first limiting rod 141. Thus, when the outer mold sleeve 11 moves further downward, the first limiting groove 112 pushes the first limiting rod 141 and the inner mold sleeve 14 to move downward synchronously. Moreover, the bottom end of the outer mold sleeve 11 also moves below the second shoulder 145. The outer mold sleeve 11 clamps the outer peripheral surface of the battery housing to fix, hold, and retain the battery housing. There is a gap between the inner peripheral surface or inner wall of the battery housing and the inner mold sleeve 14 and they do not contact. At the same time, the battery housing is also specially treated, that is, a chamfer 211 is radially inwardly provided at the end face of the battery housing, increasing the gap between the inner wall of the battery housing and the mold and reducing the possibility of contact. Thus, during the grooving process, the inner peripheral surface or inner wall of the battery housing will not be scratched to generate dust and metal fines, greatly reducing the possibility of the battery cell being contaminated.

[0075] At this time, the battery housing is firmly clamped, and the rotational movement of the upper mold and the battery starts. Specifically, since the outer mold sleeve 11, the outer ring 12, the inner mold sleeve 14, and the inner mold core 15 are connected and retained by height adjustment elements or limit rods, they can move as a whole. The power device drives the outer mold sleeve 11 to rotate, and then drives the entire upper mold to rotate synchronously with the battery. At the same time, the hob feeds to the rolling groove position of the battery housing and extrudes the battery housing. This rolling groove position is close to the third air inlet hole 152 of the inner mold core 15 and is located below the bottom end of the inner mold sleeve 14, so as to form an annular groove under the inclined surface 147. As the rolling groove is formed, the height of the battery housing and the end face decreases. Since the power device applies a large downward force through the outer mold sleeve 11, the second shoulder 145 of the inner mold sleeve 14 abuts against the end face of the battery housing under the action of this force. Therefore, as the battery housing deforms downward and the height decreases, the outer mold sleeve 11 moves downward following this deformation. Moreover, since the upper end of the first limit groove 112 of the outer mold sleeve 11 abuts against the first limit rod 141, the inner mold sleeve 14 moves downward synchronously. Thus, the first air inlet hole 113 of the outer mold sleeve 11 and the second air inlet hole of the inner mold sleeve 14 also move synchronously and are aligned with each other, ensuring the stability and integrity of the air flow path. During the downward movement of the outer mold sleeve 11, since the first groove 114 is arranged to extend upward to the upper flange 111 and lead to the outside, when the first groove 114 moves downward, it can leave space for the second limit rod 151 without interfering with the second limit rod 151 or causing additional movement of the second limit rod 151. At the same time, the lower end of the second limit groove 142 of the inner mold sleeve 14 can leave the rod 151 and move downward. During this process, the outer mold sleeve 11 and the inner mold sleeve 14 move downward synchronously. Therefore, the downward pressure exerted by the second shoulder 145 of the inner mold sleeve 14 on the end face of the battery housing remains unchanged; and as the inner mold sleeve 14 moves further downward, since the height of the inner mold core 15 remains fixed, the second height adjustment element 16 is further compressed on the inner mold core 15, thereby applying a greater pressing force to the battery cell 22 to ensure that the battery cell does not shift in the vertical direction during the rolling groove process.

[0076] Figure 15The airflow path for synchronous dust removal is shown. The external dust removal device can be started when the battery begins to rotate, so as to remove dust synchronously during the entire rolling groove process along with the extrusion of the hob. As the rolling groove progresses and the hob extrudes, dust and fine metal chips may be generated near the rolling groove position on the outer peripheral surface of the battery case, and some dust and fine metal chips may also be generated inside the battery case. However, the dust and fine metal chips at these positions can be efficiently and completely removed. Specifically, with the start of the external suction device (such as a vacuum cleaner or a vacuum pump), the airflow path formed from the outside to the inside of the rolling groove die 10 is that the airflow is radially blown horizontally from the first air inlet hole 113 of the outer die sleeve 11 to the second air inlet hole 144 at the annular groove 148 of the inner die sleeve 14, that is, the first part 1441. Then the airflow is guided to deflect vertically downward and flow along the middle part 1443. When flowing through the second part 1442, due to the existence of the inclined surface 147, the airflow changes from the vertical orientation in the middle part 1443 to multiple directions and flows from the larger opening of the ramp 147 to the area near the inclined surface 147. As can be seen from the figure, the airflow blows towards the corner formed at the rolling groove position in the direction inclined to the lower left, so as to completely remove the dust and fine metal chips at the corner. Then the airflow is deflected and blown to the third air inlet hole 152 of the inner die core along the direction inclined to the lower right, and flows upward through the third air inlet hole 152, through the inner die core 15 and the internal space of the inner die sleeve 14, and continues to flow upward to the power device and the external suction device (not shown). The suction device can be a negative ion wind system or an ordinary air flow can be used. This dust removal device, system and dust removal path can remove the dust and fine metal chips outside and inside the die to the greatest extent, greatly reducing the possibility of the battery core being contaminated.

[0077] When the rolling groove is completed, the release movement of the mold starts. Specifically, the power device drives the outer mold sleeve 11 to move upward, the outer mold sleeve 11 gradually disengages from the contact with the battery housing, and the first groove 114 also moves upward accordingly. When the first groove 114 moves to contact the second limiting rod 151 at the lower end of the second limiting groove 142, it drives the second limiting rod 151 to move upward and reach the upper end of the second limiting groove 142. The inner mold core 15 moves upward into the interior of the inner mold sleeve 14, and the bottom end of the inner mold core 15 disengages from the contact with the battery cell 22 until the bottom end of the inner mold core 15 is flush with the bottom end of the inner mold sleeve 14, and the third air inlet hole 152 moves upward into the interior of the inner mold sleeve 14. At the same time, the first limiting groove 112 and the first air inlet hole 113 of the outer mold sleeve 11 move upward, and the first air inlet hole 113 is no longer aligned with the second air inlet hole 144. During this process, the second height adjusting element 16 is compressed. However, as described above, the upward force exerted by the second height adjusting element 16 on the second shoulder 145 of the inner mold sleeve 14 is less than the downward force exerted by the first height adjusting element 13 on the outer ring 12. Therefore, the inner mold sleeve 14 remains in contact with the end face of the battery housing and exerts a downward force on the end face. The inner mold sleeve 14 cannot move upward, and the battery housing cannot be displaced or moved, thereby ensuring the smooth demolding of the outer mold sleeve 11 from the battery housing. At the same time, the second limiting rod 151 drives the inner mold core 15 to move upward to disengage from the contact with the battery cell and will not contact the inner wall of the battery housing. At the same time, the outer mold sleeve 11 is designed such that the distance from the bottom end of the outer mold sleeve 11 extending downward from the second shoulder 145 is reduced. For example, the vertical distance between the bottom end of the outer mold sleeve 11 and the second shoulder 145 is 1 mm to 2 mm, such as 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm and other values, that is, the length of the vertical section of the outer mold sleeve 11 clamping the battery housing is reduced, which can facilitate and speed up the demolding.

[0078] Meanwhile, during this process, the outer die sleeve 11 moves upward, the distance between it and the outer ring 12 increases, and the deformation amount of the first height adjustment element 13 being compressed gradually decreases. Therefore, the downward force exerted by the first height adjustment element 13 on the outer ring 12 also gradually decreases, while the deformation amount of the second height adjustment element 16 gradually increases and the force exerted on the inner die sleeve 14 gradually increases. When the second limiting rod 151 moves upward to the upper end of the second limiting groove 142, since the length of the second limiting groove 142 is equal to that of the first limiting groove 112, the upper end of the first limiting groove 112 no longer abuts against the first limiting rod 141, but moves upward to the lower end of the first limiting groove 112 to abut against or contact the first limiting rod 141. At this time, the grooving die 10 returns to the initial state before grooving. The downward force exerted by the first height adjustment element 13 on the outer ring 12 is greater than or equal to the force exerted by the second height adjustment element 16 on the inner die sleeve 14. Therefore, the first limiting rod 141 statically remains at the lower end of the first limiting groove 112, and the second limiting rod 151 remains at the upper end of the second limiting groove 142 and rests in the first groove 114. At this time, the entire grooving die 10 is in a balanced state, and the force of the second shoulder 145 vertically abutting against the end face of the battery case becomes zero. As the power device drives the outer die sleeve 11 to continue moving upward, the outer ring 12 pulls the first limiting rod 141 upward, and then pulls the inner die sleeve 14 upward to separate from the contact with the end face of the battery case.

[0079] Since the inner die sleeve 14 vertically abuts against the end face of the battery case through the second shoulder 145 without acting forces in other directions, as the inner die sleeve 14 moves straight upward, the inner die sleeve directly separates from the battery case, and the entire demoulding process is simple, fast and smooth.

[0080] In addition, in the present invention, the hob is made of tungsten steel material and undergoes mirror polishing treatment, which can increase hardness, extrude the battery case more quickly with a greater acting force, reduce the friction with the battery case, and reduce the generated dust and metal chips. The hob is changed to be supported by double-row bearings, the force is more evenly distributed, the generated runout and deflection deformation are reduced, the annular groove formed at the grooving position is more uniform, and the consistency is improved. Moreover, on the side of the battery opposite to the hob, a back tool mechanism (such as a roller) is added. During grooving, the back tool mechanism abuts against the grooving position of the battery case to increase the supporting force on the battery case, greatly reducing the torque formed by the unilateral loading of the battery case in the conventional technology and reducing the displacement and deformation of the battery case. In addition, the back tool mechanism can shape the deformation of the area around the grooving position generated by the extrusion of the hob during the grooving process to ensure the consistency of the deformation of the battery case wall and the consistency of the wall thickness.

[0081] According to the rolling groove die and equipment of the present invention, when processing a workpiece exemplified by a battery, the inner die core presses on the battery cell at the start of rolling groove, and automatically rises and disengages from the battery cell at the end of rolling groove, improving the degree of automation. Moreover, during the whole process, neither the inner die sleeve nor the inner die core contacts or scratches the inner peripheral surface and inner wall of the battery shell or the rolling groove position, reducing the wear of the die and increasing the service life of the die.

[0082] Furthermore, according to the rolling groove positioning and clamping device of the present invention, when processing the rolling groove, the outer die sleeve clamps the outer peripheral surface of the battery shell, and there is no contact between the inner peripheral surface and inner wall of the battery shell and the inner die sleeve and inner die core, greatly reducing the generation of dust and metal fines and the pollution to the battery cell. At the same time, there is a gap between the inner peripheral surface of the battery shell and the inner die sleeve, and the inner die sleeve only vertically abuts against the end face of the open end of the battery shell without forces in other directions, making the demoulding easier.

[0083] According to the rolling groove dust suction device of the present invention, the air flow generated by the dust suction device is blown to each corner from multiple directions, and can efficiently and comprehensively remove the generated dust and debris synchronously during the rolling groove process, preventing them from entering the battery cell and improving the quality and safety of the battery. The above-mentioned rolling groove die and equipment, rolling groove positioning and clamping device, and dust suction device have simple structures, few components, low costs, are easy to implement, and are convenient to operate and have a high degree of automation.

[0084] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these are only examples. The protection scope of the present invention is defined by the appended claims. Without departing from the principle and essence of the present invention, those skilled in the art can make various combinations, changes or modifications to these embodiments, but these combinations, changes and modifications all fall within the protection scope of the present invention.

Claims

1. A grooving die (10) comprising an outer die sleeve (11), an inner die sleeve (14) and an inner die core (15) which are nested around a central axis in sequence and can rotate synchronously, wherein, The power device of the grooving die (10) drives the outer die sleeve (11), and the outer die sleeve (11) can drive the inner die sleeve (14) and the inner die core (15) to move. The outer die sleeve (11) is connected to the inner die sleeve (14) through a first linkage limiting mechanism, so that the outer die sleeve (11) and the inner die sleeve (14) can move vertically synchronously relative to the inner die core (15) during the grooving process. The outer die sleeve (11) and the inner die sleeve (14) are connected to the inner die core (15) through a second linkage limiting mechanism, so that the outer die sleeve (11) and the inner die core (15) move vertically relative to the inner die sleeve (14) during the process of engaging and releasing the workpiece. When releasing the workpiece, the inner die core (15) moves before the inner die sleeve (14).

2. The grooving die (10) according to claim 1, wherein, The first linkage limiting mechanism includes: An outer ring (12), sleeved outside the outer die sleeve (11) and close to the lower part of the outer die sleeve; A plurality of first height adjusting elements (13), connected between the upper flange (111) of the outer die sleeve (11) and the outer ring (12), and the length of the first height adjusting element (13) itself can change; A plurality of first limiting rods (141), arranged on the outer peripheral surface of the inner die sleeve (14) and extending radially outward; A plurality of first limiting grooves (112), penetratingly arranged in the lower part of the wall of the outer die sleeve (11) and extending longitudinally, wherein each first limiting rod (141) passes through the corresponding first limiting groove (112) and is connected to the outer ring (12), and the first limiting rod (141) can move vertically in the first limiting groove (112).

3. The grooving die (10) according to claim 2, wherein, The second linkage limiting mechanism includes: A first groove (114), arranged on the upper inner wall of the outer die sleeve (11) and extending longitudinally; A second height adjusting element (16), arranged between the first shoulder (143) in the inner cavity of the inner die sleeve (14) and the upper end surface of the inner die core (15) inserted into the inner cavity, and the length of the second height adjusting element (16) itself can change; A second limiting rod (151), arranged on the outer periphery of the inner die core (15) and extending radially outward; A second limiting groove (142), penetratingly arranged in the middle part of the wall of the inner die sleeve (14) and extending longitudinally; wherein the second limiting rod (151) extends through the corresponding second limiting groove (142) and enters the corresponding first groove (114), and the second limiting rod (151) can move vertically in the second limiting groove (142).

4. The grooving die (10) according to claim 3, wherein, In the initial state of the grooving die (10), the first limiting rod (141) is located at the lower end of the first limiting groove (112), and the second limiting rod (151) is located at the upper end of the second limiting groove (142).

5. The grooving die (10) according to claim 4, wherein, In the initial state of the grooving die (10), the downward acting force exerted by the plurality of first height adjusting elements (13) on the outer ring (12) is greater than or equal to the upward acting force exerted by the second height adjusting element (16) on the inner die sleeve (14).

6. The grooving die (10) according to claim 5, wherein, In the initial state of the rolling groove die (10), the upward acting force exerted by the plurality of first height adjusting elements (13) on the outer die sleeve (11) is greater than or equal to the downward acting force exerted by the second height adjusting element (16) on the inner die core (15).

7. The grooving die (10) according to claim 6, wherein, The length of the first limiting groove (112) is equal to the length of the second limiting groove (142).

8. The grooving die (10) according to claim 7, wherein, During the process of the rolling groove die (10) engaging with the workpiece, the inner die sleeve (14) remains stationary, and the outer die sleeve (11) moves downward, such that the second limiting rod (151) moves from the upper end of the second limiting groove (142) to the lower end of the second limiting groove (142), and the first limiting groove (112) moves downward, such that the upper end of the first limiting groove (112) abuts against the first limiting rod (141).

9. The grooving die (10) according to claim 8, wherein, During the process of the rolling groove die (10) engaging with the workpiece, the distance between the outer die sleeve (11) and the outer ring (12) decreases, and the acting force of the plurality of first height adjusting elements (13) becomes larger.

10. The grooving die (10) according to claim 9, wherein, During the process of the rolling groove die (10) engaging with the workpiece, the distance between the inner die sleeve (14) and the inner die core (15) increases, and the acting force of the second height adjusting element (16) becomes smaller.

11. The grooving die (10) according to claim 10, wherein, During the process of the rolling groove die (10) engaging with the workpiece, after the second limiting rod (151) moves to the lower end of the second limiting groove (142) and remains stationary, the power device drives the outer die sleeve (11), the inner die sleeve (14), and the inner die core (15) to rotate synchronously to start the rolling groove process.

12. The grooving die (10) according to claim 11, wherein, During the rolling groove process, the outer die sleeve (11) and the inner die sleeve (14) move downward synchronously relative to the inner die core (15).

13. The grooving die (10) according to claim 12, wherein, After the rolling groove die (10) performs rolling groove, the outer die sleeve (11) and the inner die core (15) move upward relative to the inner die sleeve (14) until the second limiting rod (151) moves upward to the upper end of the second limiting groove (142), and the lower end of the first limiting groove (112) abuts against the first limiting rod (141).

14. The grooving die (10) according to claim 5 or 6, wherein, The first height adjusting element (13) and the second height adjusting element (16) are compression springs.

15. The grooving die (10) according to claim 14, wherein, The first shoulder (143) extends radially inwards from the inner cavity of the inner die sleeve (14) to form an inner side step, and the second height adjusting element (16) is arranged between the first shoulder (143) and the upper end face of the inner die core (15).

16. The grooving die (10) according to claim 2, wherein, A plurality of first insertion holes (123) are provided in the inner peripheral wall of the outer ring (12), and the first limiting rod (141) is inserted into the corresponding first insertion hole (123).

17. The grooving die (10) according to claim 3, wherein, The outer die sleeve (11) includes a hollow outer die sleeve body (110), the upper end flange (111) protrudes radially outwards from the upper end of the outer die sleeve body (110), the inner die sleeve (14) is inserted into the outer die sleeve body (110), and the first height adjusting element (13) is arranged between the upper end flange (111) and the outer ring (12).

18. The grooving die (10) according to claim 17, wherein, A plurality of first recesses (122) are provided in the upper end surface of the outer ring (12), and the first height adjusting element (13) is disposed in the corresponding first recess (122).

19. The grooving die (10) according to claim 18, wherein, The first groove (114) extends upward to the upper flange (111) and penetrates through the upper flange (111).

20. A grooving device, comprising a grooving die (10) according to any one of claims 1-19 and a bottom clamping mechanism.

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