Head structure for ultrasonic welding

Abstract

The present invention relates to a head structure for ultrasonic welding. According to one aspect of the present invention, the head structure for ultrasonic welding may comprise: a head body including a base surface; and a pad-type welding body and a general-type welding body provided on the base surface to weld a predetermined object, wherein at least a portion of the pad-type welding body has a cross-sectional area different from that of the general-type welding body on the basis of a plane parallel to the base surface.

Description

Head structure for ultrasonic welding

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2024-0054115, dated April 23, 2024, the entire contents of which are incorporated herein by reference.

[0003] Technology field

[0004] The present invention relates to a head structure for ultrasonic welding, and more particularly, to an ultrasonic welding head structure capable of performing ultrasonic welding by directly contacting a workpiece.

[0005] Ultrasonic welding is a process that welds two objects in contact by applying ultrasonic vibrations to them and using the frictional heat generated by the vibrations. Ultrasonic welding can be used to weld two metal objects. As a specific example, ultrasonic welding is used to join electrode tabs and electrode leads in the manufacturing process of secondary batteries.

[0006] A welding head structure is used as a component of a device for performing ultrasonic welding. The welding head structure is equipped with a plurality of welding bodies. These welding bodies have an outwardly protruding shape. When the head structure vibrates while the ends of the welding bodies are in direct contact with the object to be welded, the object is welded.

[0007] However, according to conventional welding head structures, uneven welding often occurred due to differences in weld strength between multiple welds. For example, ultrasonic vibrations were transmitted relatively concentratedly to welds located in the central portion of the head structure, resulting in overwelding. Furthermore, relatively weak vibrations were transmitted to welds located on the side portions of the head structure, resulting in underwelding.

[0008] Furthermore, conventional welding head structures often experienced varying degrees of wear across multiple welds as they operated at different welding intensities. This resulted in the unnecessary waste of usable welds as some welds wore out and reached their replacement cycle.

[0009] The present invention has been devised to solve the above problems, and the object of the present invention is to provide an ultrasonic welding head structure capable of uniformly welding an area.

[0010] Another object of the present invention is to provide a head structure for ultrasonic welding having a uniform life cycle between welded bodies.

[0011] The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0012] According to one aspect of the present invention, there is provided an ultrasonic welding head structure comprising: a head body including a base surface; and a pad-type weldable body and a general weldable body provided on the base surface to weld a predetermined object, wherein at least a portion of the pad-type weldable body has a cross-sectional area different from that of the general weldable body based on a plane parallel to the base surface.

[0013] At this time, the pad-type welded body may include a pad portion provided on the base surface; a pad-side extension portion extending from the pad portion in a direction away from the base surface and having a smaller cross-section than the pad portion; and a plurality of weld portions protruding from an end surface of the pad-side extension portion.

[0014] At this time, the pad portion includes a pad cross-section parallel to the base surface, the pad-side extension portion includes a pad-side extension cross-section parallel to the base surface, and the pad cross-section may have a larger area than the pad-side extension cross-section.

[0015] At this time, the general welded body may include a general extension portion extending from the base surface and having a smaller cross-section than the pad portion; and a plurality of welded portions protruding from an end of the general extension portion.

[0016] At this time, the pad portion includes a pad cross-section parallel to the base surface, the general extension portion includes a general extension cross-section parallel to the base surface, and the pad cross-section may have a larger area than the general extension cross-section.

[0017] At this time, the head body includes a body portion extending in one direction; and a connecting portion provided on one side of the body portion in the extension direction, and the base surface may be provided on a side of the body portion based on the extension direction of the body portion.

[0018] At this time, the pad portion can extend in parallel with the extension direction of the body portion.

[0019] At this time, the general welded body is positioned closer to the center of the base surface than the pad-type welded body in the width direction of the base surface, and the width direction of the base surface may be a direction perpendicular to the extension direction of the body portion.

[0020] At this time, the general welded body includes a first general welded body; and a second general welded body arranged parallel to the first general welded body in the width direction of the base surface, and the pad-shaped welded body can be positioned on one side of the first and second general welded bodies arranged parallel to each other.

[0021] At this time, the pad-type welded body may include a first pad-type welded body arranged on one side of the first and second general welded bodies based on the arrangement direction; and a second pad-type welded body arranged on the other side of the first and second general welded bodies based on the arrangement direction.

[0022] At this time, the pad portion and the pad side extension portion can be formed integrally.

[0023] At this time, the welded portion may have a cross-section that becomes narrower toward the end.

[0024] At this time, the plurality of welded portions may be arranged in a grid shape to form a plurality of rows and columns.

[0025] At this time, the welding part may include a welding surface provided on the end side; and a side surface connecting the welding surface and the end surface of the pad-side extension.

[0026] At this time, the angle formed by the side surface and the end surface of the pad-side extension may be 64 degrees or more and 72 degrees or less.

[0027] According to one aspect of the present invention, a general weld and a pad weld are provided on the base surface of a head body, and the pad weld is configured to have a wider cross-section than the general weld based on a surface parallel to the base surface, so that the pad weld can receive vibration from the head body through a wider area than the general weld.

[0028] Accordingly, even if the pad-type weldment is positioned in a location where it can transmit less vibration than a general weldment, the pad-type weldment can perform a welding process with the same strength as a general weldment.

[0029] Through this, the ultrasonic welding head structure according to one aspect of the present invention can weld an area with uniform strength. In addition, the life cycle of a general weld body and a pad-type weld body can be similarly aligned.

[0030] The effects of the present invention are not limited to the effects described above, and effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings.

[0031] FIG. 1 is a perspective view of a head structure for ultrasonic welding according to one embodiment of the present invention, viewed from above.

[0032] Figure 2 is an enlarged view of part A of Figure 1.

[0033] Figure 3 is an enlarged view of a portion of Figure 2. At this time, the pad-type weldment is indicated by a dotted line, and the cross-section of the pad-type weldment is indicated by a hatched surface.

[0034] Fig. 4 is a vertical cross-sectional view of the pad-type welded body illustrated in Fig. 2.

[0035] Fig. 5 is a plan view of the pad-type weldment shown in Fig. 2 as viewed from above.

[0036] Fig. 6 is an enlarged cross-sectional view so that the welded portion of the pad-type weld shown in Fig. 2 is clearly visible.

[0037] Figure 7 is an enlarged view of another part of Figure 2. At this time, the general weldment is indicated by a dotted line, and the cross-section of the general weldment is indicated by a hatched surface.

[0038] Fig. 8 is a plan view of the general welded body illustrated in Fig. 7 as viewed from above.

[0039] Preferred embodiments of the present invention are described in detail so that those skilled in the art can easily implement them. However, the present invention may be implemented in various different forms and is not limited or restricted by the following examples.

[0040] In order to clearly explain the present invention, a detailed description of a part that is irrelevant to the description or a related known technology that may unnecessarily obscure the gist of the present invention has been omitted, and when adding reference signs to components of each drawing in this specification, the same or similar reference signs are attached to the same or similar components throughout the specification.

[0041] In addition, terms and words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0042] FIG. 1 is a perspective view of an ultrasonic welding head structure according to an embodiment of the present invention, viewed from above. FIG. 2 is an enlarged view of portion A of FIG. 1. FIG. 3 is an enlarged view of a portion of FIG. 2. At this time, the pad-type weldment is indicated by a dotted line, and the cross-section of the pad-type weldment is indicated by a hatched surface. FIG. 4 is a vertical cross-sectional view of the pad-type weldment illustrated in FIG. 2. FIG. 5 is a plan view of the pad-type weldment illustrated in FIG. 2, viewed from above. FIG. 6 is an enlarged cross-sectional view so that the welded portion of the pad-type weldment illustrated in FIG. 2 is clearly visible. FIG. 7 is an enlarged view of another portion of FIG. 2. At this time, the general weldment is indicated by a dotted line, and the cross-section of the general weldment is indicated by a hatched surface. FIG. 8 is a plan view of the general weldment illustrated in FIG. 7, viewed from above. At this time, in order to simplify the drawings, the welded portions of the pad-type welded body and the general welded body are not shown in FIGS. 1 to 4 and FIG. 7.

[0043] FIGS. 1 to 8 disclose a head structure (1) for ultrasonic welding (hereinafter referred to as a “head structure”) according to one embodiment of the present invention. Referring to FIG. 1, the head structure (1) according to one embodiment of the present invention may be a head structure for performing an ultrasonic welding process.

[0044] To this end, a portion of the head structure (1) according to the present embodiment may be operatively coupled with another external device. For example, the connecting portion (14) of the head structure (1) described below may be coupled with the other device. The head structure (1) may receive vibration energy from the other device to perform a welding process.

[0045] Hereinafter, the configuration of a head structure according to one embodiment of the present invention will be specifically described.

[0046] Referring to FIG. 1, a head structure (1) according to one embodiment of the present invention may include a head body (10). The head body (10) may be configured to provide a base for a welded body (20, 30) described below. The head body (10) may transmit vibration applied from an external device to the welded body (20, 30).

[0047] In this embodiment, the head body (10) may include a body portion (12) extending in one direction. As illustrated, the body portion (12) may be provided as a rod-shaped member extending along the front-rear direction (X-axis direction).

[0048] At this time, in the present embodiment, a welding space (13) may be provided on the side of the body part (12) based on the extension direction (X-axis direction) of the body part (12). Here, the side in the extension direction (X-axis direction) may mean a part located in a direction perpendicular to the extension direction (X-axis direction) (a direction parallel to the YZ plane). In other words, the side may mean a part located on the circumference side of the body part (12).

[0049] In this embodiment, the welding space (13) may be a space where a work object to be welded by the head structure (1) is placed. As an example, the work object may be an electrode lead and an electrode tab, which are components of a secondary battery.

[0050] At this time, in the present embodiment, the welding space (13) of the body part (12) may be formed by recessing the side of the body part (12). As illustrated, the welding space (13) may be provided on the inside of a portion where the side of the body part (12) is recessed inward. This recessed portion may also perform the function of indicating the portion where the work object is placed.

[0051] At this time, in the present embodiment, the body part (12) may be provided with a base surface (12a). The base surface (12a) may be a surface on which a welded body (20, 30) described later is provided. A workpiece for a welding process may be placed on the base surface (12a).

[0052] In this embodiment, the base surface (12a) can define a portion of the welding space (13). The base surface (12a) can be provided on the bottom of a concavely sunken portion of the side of the body portion (12). The base surface (12a) can extend in the front-back direction (X-axis direction) along the length of the body portion (12).

[0053] Meanwhile, in the present embodiment, the welding space (13) and the base surface (12a) of the body part (12) may be formed to face each other (or symmetrically) on both sides of the body part (12). As illustrated, the welding space (13) and the base surface (12a) may be formed to face each other in the vertical direction (Z-axis direction) on the upper and lower sides of the body part (12).

[0054] Through this, when the weld (20, 30) provided on one of the two opposing base surfaces (12a) reaches the end of its life, the head structure (1) can be turned over and the weld (20, 30) provided on the other surface can be used. Therefore, more welding processes can be performed with one head structure (1).

[0055] Referring again to FIG. 1, the head body (10) of the head structure (1) according to one embodiment of the present invention may include a coupling portion (14). The coupling portion (14) may be configured to operatively couple the head body (10) with another external device.

[0056] In this embodiment, the coupling portion (14) may be provided on one side of the extended portion of the body portion (12). As illustrated, the coupling portion (14) may be provided on the front (positive direction of the X-axis) side portion of the body portion (12).

[0057] In this embodiment, the coupling member (14) may be provided as a cylindrical member that can be coupled to a predetermined hole. However, the shape or structure of the coupling member (14) is not particularly limited as long as it can be coupled to another external device.

[0058] Meanwhile, in the head structure (1) according to one embodiment of the present invention, the intensity of vibration transmitted through the head body (10) may vary depending on the location of the base surface (12a). For example, the intensity of vibration transmitted may be stronger in the central portion of the base surface (12a) than in the side portions.

[0059] This is because the central portion of the base surface (12a) is positioned closer to the joint (14) through which vibration is transmitted. This difference may cause uneven welding and differences in the life cycle of the weldment (20, 30).

[0060] Here, the central portion and side portion of the base surface (12a) may mean a portion positioned adjacent to the center of the body portion (12) based on the width direction (Y-axis direction) of the base surface (12a) and another portion positioned relatively on the side.

[0061] Referring to FIGS. 1 to 4, a head structure (1) according to one embodiment of the present invention may include a plurality of welded bodies (20, 30). The welded bodies (20, 30) may be configured to directly contact a workpiece and perform welding.

[0062] At this time, the welded body (20, 30) of the head structure (1) according to one embodiment of the present invention may include a pad-type welded body (20). The pad-type welded body (20) may include a pad portion (22) provided on the base surface (12a).

[0063] In this embodiment, the pad portion (22) may be provided as a pad-shaped member provided on the base surface (12a). The pad portion (22) may extend along the extension direction (X-axis direction) of the body portion (12).

[0064] At this time, the pad portion (22) may have a pad cross-section (23) based on a surface parallel to the base surface (12a). The pad cross-section (23) may have a wider area than the general extension cross-section (33) of the general welded body (30) described later.

[0065] Through this, the pad-type welded body (20) can transmit vibrations over a wider area than the general welded body (30) described later. The effect resulting from this will be described later along with the relative positional relationship between the pad-type welded body (20) and the general welded body (20).

[0066] Meanwhile, in the present embodiment, the pad portion (22) is provided as a hexahedral pad member. However, the shape of the pad portion (22) is not particularly limited as long as the pad cross-section (23) described above can have a wider area than the cross-section of the general welded body (20).

[0067] For example, the pad portion (22) may have a polygonal columnar shape with a cross-sectional area that becomes smaller as it goes upward. In this case, it may be preferable that the upper surface of the pad portion (22) be larger than the general extension cross-section (33) described later.

[0068] A pad-shaped welded body (20) of a head structure (1) according to one embodiment of the present invention may include a pad-side extension portion (24). The pad-side extension portion (24) may extend from the pad portion (22). At this time, the pad-side extension portion (24) may extend upward (in the positive direction of the Z-axis) away from the base surface (12a).

[0069] In this embodiment, the pad-side extension portion (24) may have a pad-side extension cross-section (25) based on a surface parallel to the base surface (12a). At this time, the pad-side extension cross-section (25) may have a smaller area than the pad cross-section (23) described above. Through this, vibration transmitted through the pad portion (22) may be concentrated at the pad-side extension portion (24) and its intensity may be amplified.

[0070] Meanwhile, in the present embodiment, the pad-side extension (24) is provided as a member in the shape of a square pillar extending vertically (in the Z-axis direction). However, the shape of the pad-side extension (24) is not particularly limited.

[0071] For example, the pad-side extension (24) may have a triangular prism or hexagonal prism shape, and one section may have different thicknesses from another section in the vertical direction (Z-axis direction).

[0072] Referring to FIGS. 4 to 6, the pad-shaped welded body (20) of the head structure (1) according to one embodiment of the present invention may include a plurality of welded portions (26). The welded portions (26) may protrude from the extension direction end surface (24a) of the pad-side extension portion (24).

[0073] In this embodiment, the welded portion (26) may have a shape in which the cross-section becomes narrower toward the end. This may be to concentrate and amplify the vibration transmitted through the pad-side extension portion (24) at the end.

[0074] In this embodiment, the welded portion (26) may include a welding surface (26a) provided at an end portion and a side surface (26b) connecting the welding surface (26a) and the end surface (24a). The welding surface (26a) may be a surface that comes into contact with an object, and the side surface (26b) may be provided along the periphery of the welded portion (26).

[0075] At this time, the welding surface (26a) may be rectangular, and the side surface (26b) may be composed of four sides of the end surface (24a) and four inclined surfaces connecting the end surface (24a), respectively. In other words, the welding portion (26) may be provided as a member in the shape of a trapezoidal column whose cross-section becomes narrower as it goes upward (in the positive direction of the Z-axis), as illustrated.

[0076] At this time, according to the head structure (1) according to one embodiment of the present invention, the end surface (24a) and the side surface (26b) can form a predetermined angle. Hereinafter, the predetermined angle is referred to as angle B.

[0077] In this embodiment, angle B may be appropriately set as needed. For example, angle B may be set in consideration of the life cycle of the weldment (20, 30) and / or the welding defect rate due to the weldment (26).

[0078] As a specific example, the inventors of the present invention confirmed that as the angle B decreases, the life cycle of the weld (20, 30) decreases. In addition, the inventors of the present invention confirmed that the cause of this phenomenon is that the change in the area of ​​the weld surface (26a) due to wear of the weld (20, 30) increases as the angle B decreases.

[0079] Such excessive change in the area of ​​the welding surface (26a) may cause welding to be performed in an area that is larger or smaller than the designed area, or may cause problems such as reduced welding reliability.

[0080] Considering the above research results, the present inventors have confirmed that when the angle B is 64 degrees or greater, the change in area of ​​the weld surface (26a) due to wear can be limited to an appropriate range. Taking this into account, the angle B may be 64 degrees or greater.

[0081] As another specific example, the inventors of the present invention confirmed that as the angle B increases, the welding defect rate of the weldment (20, 30) increases. The inventors of the present invention confirmed that the cause of the above phenomenon is that as the angle B increases, the vibration energy is not properly concentrated on the welding surface (26a) of the weldment (26).

[0082] Considering the above research results, the inventors were able to confirm that when angle B is less than 72 degrees, welding defects occur below the confidence level. Considering this, angle B can be less than 72 degrees. Of course, angle B may have a size outside the aforementioned range, as needed.

[0083] Meanwhile, in the present embodiment, the welded portion (26) has been described as having a trapezoidal columnar shape with a cross-section that narrows toward the upper side (positive direction of the Z-axis). However, the shape or structure of the welded portion (26) is not particularly limited as long as it can concentrate or amplify ultrasonic vibrations transmitted to the welded surface (26a).

[0084] Again, referring to FIGS. 2, 7 and 8, the weldment (20, 30) of the head structure (1) according to one embodiment of the present invention may include a general weldment (30). The general weldment (30) may include a general extension (32) extending outward from the base surface (12a). The general extension (32) may perform a function of transmitting and amplifying vibration transmitted from the head body (10) to the weldment (34) described below.

[0085] At this time, in the present embodiment, the general extension part (32) may have a hexahedral shape extending upward (in the positive direction of the Z-axis). Of course, the shape or structure of the general extension part (32) may be modified as needed. For example, the general extension part (32) may have a polygonal columnar shape, or the thickness or width of one section may be different from that of another section in the vertical direction (Z-axis direction).

[0086] Meanwhile, in the present embodiment, the general extension portion (32) may have a general extension cross-section (33) based on a plane parallel to the base surface (12a). At this time, the general extension cross-section (33) may have a smaller area than the pad cross-section (23) described above. In other words, the pad cross-section (23) may have a larger area than the general extension cross-section (33).

[0087] This may be to ensure that the area of ​​the general welded body (30) that receives vibration from the head body (10) is smaller than that of the pad-type welded body (20). The effect resulting from this will be described later along with the relative positional relationship between the pad-type welded body (20) and the general welded body (30).

[0088] A general welded body (30) of a head structure (1) according to one embodiment of the present invention may include a plurality of welded portions (34). The welded portions (34) may protrude from an end face (32a) in the extension direction of a general extension portion (32).

[0089] In this embodiment, the weld (34) may include a welding surface (34a) provided on the end side of the weld (34) and a side surface (34b) connecting the welding surface (34a) and the end surface (32a) to each other. At this time, the weld (34) of the general weld (30) according to this embodiment may be configured in the same manner as the weld (26) of the pad-type weld (20) described above.

[0090] At this time, referring to FIGS. 3 and 7, in the present embodiment, the height at which the end surface (32a) of the general welded body (30) is spaced from the base surface (12a) may be the same as the height at which the end surface (24a) of the pad-type welded body (20) is spaced from the base surface (12a). Of course, the end surfaces (32a, 24a) may be configured so that the heights at which they are spaced from the base surface (12a) are different from each other.

[0091] Hereinafter, the relative positions of the pad-type weldment (20) and the general weldment (30) of the present invention and the resulting effects will be specifically described.

[0092] Referring to FIGS. 1 to 3 and 7, in a head structure (1) according to one embodiment of the present invention, the relative positions of a pad-type welded body (20) and a general welded body (30) can be appropriately arranged. For example, the pad-type welded body (20) and the general welded body (30) can be arranged in consideration of the welding strength performed in each welded body (20, 30) and / or the life cycle of the welded body (20, 30).

[0093] For example, in the present embodiment, the unit area of ​​the vibration energy transmitted to the weldment (20, 30) through the base surface (12a) of the head body (10) may be larger in the central portion of the base surface (12a) than in the side portion. Taking this into consideration, the pad-type weldment (20) may be positioned in the side portion of the base surface (12a), and the general weldment (30) may be positioned in the central portion of the base surface (12a).

[0094] Here, the central portion refers to a portion positioned adjacent to the center of the body portion (12) based on the width direction (Y-axis direction) of the base surface (12a), and the side portion refers to a portion closer to the edge side in the width direction (Y-axis direction) than the central portion.

[0095] Referring to the drawings, in the present embodiment, the pad-type welded body (20) may include a first pad-type welded body (20-1) and a second pad-type welded body (20-2), and the general welded body (30) may include a first general welded body (30-1) and a second general welded body (30-2).

[0096] And, the first and second general welded bodies (30-1, 30-2) can be arranged in parallel in the width direction (Y-axis direction) of the base surface (12a), and the first and second pad-type welded bodies (20-1, 20-2) can be arranged on the outside of the first and second general welded bodies (30-1, 30-2) in the width direction (Y-axis direction) of the base surface (12a), respectively.

[0097] Accordingly, the pad-type welded body (20) and the general welded body (30) can perform the welding process with the same or similar strength, and each welded body (20, 30) can have the same or similar life cycle. This is because the difference in cross-sectional area between the pad-type welded body (20) and the general welded body (30) can offset the difference in vibration energy per unit area transmitted between the side portion and the central portion of the base surface (12a).

[0098] To be more specific, in the side portion of the base surface (12a), the vibration energy per unit area transmitted from the head body (10) is relatively small, but the pad-type welded body (20) receives vibrations through the relatively wide pad cross-section (23). In contrast, in the central portion of the base surface (12a), the vibration energy per unit area is relatively large, but the general welded body (30) receives vibrations through the relatively narrow general extension cross-section (33). Through this, the welded bodies (20, 30) can perform a welding process with uniform strength and have the same or similar life cycles.

[0099] In order to confirm the superiority of the head structure (1) according to the present embodiment, the inventors performed a test of welding two metal sheets using the head structure (1) according to the present embodiment and the head structure according to a comparative example.

[0100] In the head structure (1) according to one embodiment of the present invention, the specific shape of the pad-type welded body (20) is as follows. The X-axis direction length and Y-axis direction length of the pad portion (22) are 8 mm and 2 mm, respectively, and the X-axis direction length and Y-axis direction length of the pad-side extension portion (24) are 4 mm and 2 mm, respectively.

[0101] In the head structure (1) according to one embodiment of the present invention, the specific shape of the general welded body (30) is as follows. The X-axis direction length and Y-axis direction length of the general extension portion (32) are 4 mm and 2 mm, respectively.

[0102] According to the comparative example, the head structure has four general welded bodies (30) arranged in the left-right direction (Y-axis direction) on the base surface (12a). The results of the test performed under different welding conditions are as shown in [Table 1] below.

[0103] Welding Conditions Comparison Example Example Amplitude [%] Time [s] Pressure [Mpa] 1st 2nd 3rd 4th 1st 2nd 3rd 4th 540.0540.03XXXXXXXX570.057XXXXOXOO600.060XOOXOOOO650.060XOOXOOOO680.068OOOXOOOO710.071OOOXOOOO740.074OOOOOOOO

[0104] In [Table 1], the amplitude (%) means the ratio between the maximum amplitude and the minimum amplitude. It can be understood that the larger the amplitude (%), the greater the energy applied to the head structure according to the embodiment or comparative example. In [Table 1], numbers 1 to 4 name the welds provided on the base surface of the head structure in the order arranged from the left (negative direction of the Y-axis) to the right (positive direction of the Y-axis). For example, numbers 1 and 4 in the comparative example and embodiment will mean welds arranged at the outermost side based on the left-right direction, and numbers 1 and 4 in the embodiment will be pad-type welds (20).

[0105] In [Table 1], an 'X' indicates that the two metal foils welded by the welded body indicated in the same row are not fully welded and can be separated by an external force. Conversely, an 'O' indicates that the two metal foils welded by the welded body indicated in the same row are fully welded and cannot be separated by an external force. In this case, the external force may be a force pulled by the worker's hand.

[0106] Referring to [Table 1], it can be confirmed that in the embodiment, both metal films are welded by welds No. 1 to 4 even in a lower amplitude region compared to the comparative example. This suggests that in the head structure (1) according to the present embodiment, the energy difference per unit area between the outermost welds No. 1 and 4 and the inner welds No. 2 and 3 can be offset, and thus welding can be performed with uniform quality under various welding conditions.

[0107] Meanwhile, the relative positional relationship between the pad-type weld (20) and the general weld (30) can be appropriately modified by considering the shape of the body part (12) or the base surface (12a) and the vibration energy per unit area transmitted at their local locations.

[0108] Referring again to FIGS. 1 and 2, the body portion (12) of the head structure (1) according to one embodiment of the present invention, the pad-type welded body (20), and the general welded body (30) can be formed integrally. Here, the fact that the two components are formed integrally can mean that the two components are not physically and spatially separated or distinguished.

[0109] Through this, vibration energy can be more effectively transmitted from the body part (12) to the weld (20, 30). Of course, if the vibration energy can be properly transmitted, the body part (12) and the weld (20, 30) can be provided as separate members and then assembled or joined together.

[0110] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and various embodiments are possible within the scope equivalent to the technical idea of ​​the present invention and the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0111] [Explanation of symbols]

[0112] 1: Head structure for ultrasonic welding

[0113] 10: Head body

[0114] 12: Body

[0115] 12a: Base surface

[0116] 14: Joint

[0117] 20: Pad-type welded body

[0118] 22: Pad section

[0119] 24: Pad side extension

[0120] 24a: Single-sided

[0121] 26: Welding

[0122] 26a: Welding surface

[0123] 26b: Side

[0124] 30: General welded body

[0125] 32: General extension

[0126] 32a: Single-sided

[0127] 34: Welding

[0128] 34a: Welding surface

[0129] 34b: Side

Claims

1. A head body including a base surface; and Includes a pad-type welding body and a general welding body that are provided on the above base surface and can weld a predetermined object, An ultrasonic welding head structure, wherein at least a portion of the pad-type weldment has a cross-sectional area different from that of the general weldment based on a plane parallel to the base surface.

2. In paragraph 1, The above pad-type welded body is, A pad portion provided on the above base surface; A pad-side extension portion extending away from the pad portion in a direction away from the base surface and having a smaller cross-section than the pad portion; and An ultrasonic welding head structure comprising a plurality of welding portions protruding from an end surface of the pad-side extension portion.

3. In paragraph 2, The above pad portion includes a pad cross-section parallel to the base surface, The above pad-side extension portion includes a pad-side extension cross-section that is parallel to the base surface, An ultrasonic welding head structure, wherein the pad cross-section has a wider area than the pad-side extension cross-section.

4. In paragraph 2, The above general welded body is, A general extension portion extending from the base surface and having a smaller cross-section than the pad portion; and An ultrasonic welding head structure comprising a plurality of welding portions protruding from an end of the general extension portion.

5. In paragraph 4, The above pad portion includes a pad cross-section parallel to the base surface, The above general extension portion includes a general extension cross-section parallel to the base surface, The above pad cross-section is a head structure for ultrasonic welding, having a wider area than the above general extension cross-section.

6. In paragraph 4, The above head body, a body portion extending in one direction; and Including a connecting portion provided on one side of the extension direction of the above body portion, The above base surface is an ultrasonic welding head structure provided on a side of the body part based on the extension direction of the body part.

7. In paragraph 6, The above pad portion is an ultrasonic welding head structure that extends parallel to the extension direction of the body portion.

8. In paragraph 6, The above general welded body is positioned closer to the center of the base surface than the pad-type welded body in the width direction of the base surface, An ultrasonic welding head structure, wherein the width direction of the base surface is perpendicular to the extension direction of the body portion.

9. In paragraph 8, The above general welded body is, First general type welded body; and It includes the first general welded body and the second general welded body arranged parallel to the width direction of the base surface, The above pad-type welded body is an ultrasonic welding head structure positioned on one side of the first and second general-type welded bodies arranged in parallel.

10. In paragraph 9, The above pad-type welded body is, A first pad-type welded body arranged on one side of the first and second general welded bodies based on the arrangement direction; and An ultrasonic welding head structure including a second pad-type weld body arranged on the other side of the first and second general-type weld bodies based on the arrangement direction.

11. In paragraph 2, An ultrasonic welding head structure in which the pad portion and the pad side extension portion are formed integrally.

12. In paragraph 2, The above welding part is an ultrasonic welding head structure having a cross-section that becomes narrower toward the end.

13. In paragraph 2, An ultrasonic welding head structure in which the above plurality of welding parts are arranged in a grid shape to form a plurality of rows and columns.

14. In paragraph 2, The above welding part, Welding surface provided on the end side; and An ultrasonic welding head structure including a side surface connecting the welding surface and the end surface of the pad-side extension.

15. In paragraph 14, An ultrasonic welding head structure, wherein the angle formed by the side surface and the end surface of the pad-side extension is 64 degrees or more and 72 degrees or less.

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