Ultrasonic welding device

Abstract

To provide an ultrasonic welding device that strongly welds sheet-shaped members made of fiber material so that the members do not peel off from resin molded products.SOLUTION: There is provided an ultrasonic welding device, in which a convex surface 30a and a concave bottom surface 30c are formed on the pressing surface of a tool horn 30, both members are connected by a guide surface 30b, a molten portion melted on the convex surface 30a of the tool horn 30 is allowed to flow from the surface of the convex surface 30a of the tool horn into the concave bottom surface 30c via the guide surface 30b, and a resin molded product 10 melted on the convex surface 30a of the tool horn 30 and a fiber material 20 are entwined to form an impregnated range solidified in the impregnated state.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an ultrasonic welding device that welds a sheet-like member made of a fibrous material (hereinafter referred to as a "fibrous member" in this application) to a resin molded product, and in particular to an ultrasonic welding device that strongly welds a sheet-like member (fibrous member) made of a fibrous material such as a medical filter or a sludge treatment membrane so that it does not peel off from the resin molded product. [Background technology]

[0002] In the past, when welding a fibrous material using nonwoven fabric as a support material to the surface of a resin molded product, the fibrous material was placed on top of the resin molded product and then welded by directly pressing a hot plate or the tool horn of an ultrasonic welding machine against the fibrous material.

[0003] Fig. 24 is a perspective view showing the positional relationship between a frame-shaped resin molded product 10 and a rectangular sheet-shaped fiber member 20 before welding. Conventionally, a peripheral vicinity portion 21 of the fiber member 20 is placed on the step portion 10a of the resin molded product 10, and welding is performed by pressing an ultrasonically vibrating tool horn 90 against the step portion 10a as shown in Fig. 25. Regarding the welding points 25, only the four corners or multiple welding points are welded at a predetermined interval depending on the required adhesion state and adhesion strength. Therefore, when a large adhesion strength is required or when the entire circumference of the fiber member is welded to the resin molded product, many welding points are welded, and therefore a processing time proportional to the number of welding points is required (see, for example, Patent Documents 1 and 2).

[0004] Figure 26(a) is a cross-sectional view showing the positional relationship between the resin molded product 10, the fiber material 20 and the tool horn 90 before the welding operation, and Figure 26(b) shows a cross-sectional view when the ultrasonically vibrating tool horn 90 is pressed against the fiber material 20 superimposed on the resin molded product 10 to weld it.

[0005] 26(c) shows a cross-sectional view of the resin molded article 10 and the fiber material 20 after welding. In the area pressed by the lower surface of the tool horn 90, both the total thickness (H0) of the resin molded article 10 and the fiber material 20 before welding and the thickness (H1) of the resin molded article 10 are compressed from before welding.

[0006] The area where the tool horn 90 is pressed is the welded area where the resin molded product 10 and the fiber material 20 are welded, while the area where the tool horn 90 is not pressed is the non-welded area where the fiber material 20 on the resin molded product 10 remains separated and is simply in contact. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 7-24270 [Patent Document 2] JP 2010-208031 A Summary of the Invention [Problem to be solved by the invention]

[0008] When multiple welding points are welded at a specified distance apart as in the conventional method, the fiber members 20 on the resin molded product 10 remain separated and simply in contact in the non-welded areas as shown in FIG.

[0009] Medical filters and sludge treatment membranes become clogged with continued use. In order to maintain the filter performance, cleaning work is performed to remove deposits that have adhered to the fiber material 20, and this can result in the application of a larger external force than during normal use. As a result, after cleaning several times, the welded material may come off or the fiber material may break. When the welded material comes off or the fiber material breaks, it becomes necessary to replace it as a consumable item with a new one.

[0010] The present invention has been made to solve these problems, and its object is to provide an ultrasonic welding device that can strongly and stably weld a sheet-like member so that it does not peel off from a resin molded product.

[0011] More specifically, the object of the present invention is to provide an ultrasonic welding device that can strongly and stably weld a fiber material to a resin molded product by forming an impregnated area between two welding areas where the resin molded product and the fiber material become entangled, impregnated, and solidified, even when multiple welding points are welded at a specified interval. [Means for solving the problem]

[0012] In order to achieve the above-mentioned object, the ultrasonic welding apparatus of the present invention includes an ultrasonic welding device in which a fiber material is placed on a resin molded product placed on an anvil, and a tool horn that is ultrasonically vibrating from the surface of the fiber material is pressed against the fiber material and the resin molded product to weld the fiber material and the resin molded product.The ultrasonic welding apparatus is configured to form adjacent convex and concave portions on the pressing surface of the tool horn, with the convex surface and the concave bottom surface connected by a guide surface, and the fiber material and the resin molded product are pressed by the convex portion of the ultrasonically vibrating tool horn to form a welded area where the two are welded together, and to flow the molten portion of the resin molded product that has been melted by the convex portion of the tool horn from the convex surface of the tool horn toward the bottom surface of the concave portion to form an impregnation area where the molten portion of the resin molded product and the fiber material are entangled, and to form the welded area and the impregnation area adjacent to each other.

[0013] In the ultrasonic welding apparatus of the present invention, when adjacent convex portions and concave portions are formed on the pressing surface of the tool horn, with the convex portion surface and the concave portion bottom surface connected by a guide surface, the convex portions and concave portions are formed alternately and repeatedly, so that within the area where the fiber material and the resin molded product are welded, the welding area formed by the tool horn convex portion and the impregnation area formed by the tool horn concave portion are alternately and continuously repeated.

[0014] In other words, in the present invention, the convex portion of the ultrasonically vibrating tool horn presses the fiber material and the resin molded product to form a welded area where the two are welded together, and the molten portion of the resin molded product melted by the convex portion of the tool horn is caused to flow from the surface of the convex portion of the tool horn toward the bottom surface of the recess, forming an impregnation area where the molten portion of the resin molded product and the fiber material are entangled, so that the welded area and the impregnation area are formed adjacent to each other.

[0015] In the ultrasonic welding apparatus of the present invention, when adjacent convex portions and concave portions are formed on the pressing surface of the tool horn, with the convex portion surface and the concave portion bottom surface connected by a guide surface, the convex portions and concave portions are formed alternately and repeatedly in one direction on the pressing surface.

[0016] In the ultrasonic welding apparatus of the present invention, when adjacent convex portions and concave portions are formed on the pressing surface of the tool horn by connecting the surface of the convex portion and the bottom surface of the concave portion with a guide surface, multiple convex portions and concave portions are formed in parallel, alternating in one direction on the pressing surface.

[0017] In the ultrasonic welding apparatus of the present invention, when forming adjacent convex portions and concave portions on the pressing surface of the tool horn by connecting the surface of the convex portion and the bottom surface of the concave portion with a guide surface, the convex portions and concave portions are formed by alternating and repeating in one direction on the pressing surface and intersecting at a predetermined angle.

[0018] In the ultrasonic welding apparatus of the present invention, when adjacent convex portions and concave portions are formed on the pressing surface of the tool horn by connecting the surface of the convex portion and the bottom surface of the concave portion with a guide surface, the convex portions and concave portions are formed alternately and radially from the inside to the outside of the pressing surface.

[0019] In the ultrasonic welding apparatus of the present invention, the pressing surface of the tool horn is circular, and circular convex portions and circular concave portions, with the surface of the convex portion and the bottom surface of the concave portion connected by a guide surface, are formed repeatedly radially from the inside to the outside of the pressing surface.

[0020] In the ultrasonic welding apparatus of the present invention, the pressing surface of the tool horn is polygonal, and polygonal convex portions and polygonal concave portions, with the convex surface and the concave bottom surface connected by a guide surface, are formed repeatedly radially from the inside to the outside of the pressing surface.

[0021] In the ultrasonic welding apparatus of the present invention, small protrusions are provided on the surface of the convex portion formed on the pressing surface of the tool horn. Effect of the Invention

[0022] The ultrasonic welding device of the present invention achieves the required adhesion state and high adhesion strength in the welding area, and at the same time, the area adjacent to the welding area becomes an impregnation area in which the molten resin molded product is entangled with the fiber material, thereby achieving good adhesion state and high adhesion strength between the fiber material and the resin molded product.

[0023] The ultrasonic welding device of the present invention can weld the sheet-like member to the resin molded product in an area adjacent to the welding area without peeling it off. Therefore, there is an effect that a good adhesion state and a sufficiently large adhesion strength can be obtained between the sheet-like member and the resin molded product without having to spend a lot of work time welding the entire circumference of the fiber member to the resin molded product as in the conventional method.

[0024] In the ultrasonic welding device of the present invention, the adjacent portion of the welding area is not a non-welded area where the resin molded product and the fiber material are simply in contact with each other as in the conventional method, but is formed as an impregnated area where the resin molded product and the fiber material are entangled and solidified. Therefore, even if an external force larger than that in normal use is applied to the welded resin molded product and fiber material, for example, during cleaning work of the fiber material, the weld will not come off or the fiber material will not break. [Brief description of the drawings]

[0025] [Figure 1] 1A is a schematic side view showing a state of the ultrasonic welding apparatus of the present invention before a welding operation, and FIG. 1B is a schematic side view showing a state of the ultrasonic welding apparatus of the present invention during a welding operation. [Diagram 2] 3(a)(b)(c)(d) are cross-sectional diagrams showing the welding procedure of the ultrasonic welding apparatus of the present invention. [Diagram 3](a)(b)(c)(d)(e) Transition diagrams showing in cross section the process in which the molten part of the resin molded product melted at the convex part of the tool horn moves toward the fiber material, becomes entangled with it, and impregnates it during the welding process of this invention. [Figure 4] 4(a)(b)(c)(d) are cross-sectional transition diagrams showing the welding procedure for welding a filter sheet made of looped fibers to a frame-shaped resin molded product using the ultrasonic welding device of the present invention. [Diagram 5] FIG. 2 is a plan view showing a resin molded product and a fiber member welded by the ultrasonic welding device of the present invention. [Figure 6] FIG. 2 is a partial external perspective view of the tool horn according to the embodiment of the present invention, viewed from below. [Figure 7] FIG. 2A is a partial front view of a tool horn according to a first modified example of an embodiment of the present invention; FIG. 2B is a partial front view of a tool horn according to a second modified example of an embodiment of the present invention; [Figure 8] (a)(b)(c)(d)(e) Transition diagrams showing, in cross section, an image of how the molten portion of the resin molded product melted at the convex part of the tool horn moves toward the fiber material, becomes entangled with it, and impregnates it, when a tool horn in which the guide surface of the tool horn is curved instead of inclined, is used as a modified example of the ultrasonic welding device of the present invention. [Figure 9] (a)(b)(c)(d) Arrows indicate the image of the alternating convex and concave portions on the pressing surface of the tool horn, with the convex surface and the concave bottom surface connected by a guide surface. [Figure 10] 5A is a cross-sectional view of the tip of a tool horn of a second embodiment of an ultrasonic welding device of the present invention, and FIG. 5B is a bottom view showing the pressing surface of the tool horn. [Figure 11] 13A is a cross-sectional view of a tip portion of a tool horn of a third embodiment of an ultrasonic welding device of the present invention, and FIG. 13B is a bottom view showing a pressing surface of the tool horn. [Figure 12] 13A is a cross-sectional view of a tip portion of a tool horn of a fourth embodiment of an ultrasonic welding device of the present invention, and FIG. 13B is a bottom view showing a pressing surface of the tool horn. [Figure 13] FIG. 11 is an external perspective view of a structure welded using a tool horn of a fourth embodiment of the ultrasonic welding device of the present invention. [Figure 14]FIG. 13 is an external enlarged perspective view of a welded portion of a structure welded using a tool horn of a fourth embodiment of the ultrasonic welding device of the present invention. [Figure 15] 13 is a cross-sectional view of a tip portion of a tool horn according to a modified example of the fourth embodiment of the ultrasonic welding device of the present invention. FIG. [Figure 16] FIG. 13 is an external enlarged perspective view of a welded portion of a structure welded using a tool horn according to a modified example of the fourth embodiment of the ultrasonic welding device of the present invention. [Figure 17] 13A is a cross-sectional view of a tip portion of a tool horn of a fifth embodiment of an ultrasonic welding device of the present invention, and FIG. 13B is a bottom view showing a pressing surface of the tool horn. [Figure 18] FIG. 13 is an external perspective view of a tool horn of a fifth embodiment of an ultrasonic welding device of the present invention, as viewed from diagonally below. [Figure 19] 13(a), (b), (c), and (d) are cross-sectional transition diagrams showing a welding procedure of an ultrasonic welding apparatus according to a fifth embodiment of the present invention. [Figure 20] FIG. 13 is an external perspective view of a structure welded using a tool horn of a fifth embodiment of the ultrasonic welding device of the present invention. [Figure 21] 13A is a cross-sectional view of the tip of a tool horn according to a first modified example of the fifth embodiment of the ultrasonic welding device of the present invention, and FIG. 13B is a bottom view showing the pressing surface of the tool horn. [Figure 22] 13A is a cross-sectional view of a tip portion of a tool horn according to a second modified example of the fifth embodiment of the ultrasonic welding device of the present invention, and FIG. 13B is a bottom view showing the pressing surface of the tool horn. [Figure 23] 13A is a cross-sectional view of a tip portion of a tool horn according to a third modified example of the fifth embodiment of the ultrasonic welding device of the present invention, and FIG. 13B is a bottom view showing the pressing surface of the tool horn. [Figure 24] FIG. 13 is an exploded perspective view showing the positional relationship between a resin molded product and a fiber member to be welded in a conventional ultrasonic welding device. [Diagram 25] FIG. 13 is an exploded perspective view showing the positional relationship when a resin molded product and a fiber member are welded together using a conventional ultrasonic welding device. [Figure 26] 4(a), (b), and (c) are cross-sectional views showing the transition state when a resin molded product and a fiber material are welded together using a conventional ultrasonic welding device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] First Embodiment FIG. 1(a) shows a schematic side view of the ultrasonic welding apparatus of the present invention in a state before welding operation, and FIG. 1(b) shows a schematic side view of the ultrasonic welding apparatus of the present invention in a state during welding operation.

[0027] In the ultrasonic welding apparatus of the present invention, an anvil 50 is placed on the lower horizontal part 51a of a U-shaped frame 51, and an air cylinder, which is a tool horn lifting means 60, is attached downward on the upper horizontal part 51c of the frame 51. A slider 62 is attached to the tip of an actuator 61 of the lifting means 60, and an ultrasonic vibration means 40 is attached to the slider 62. A tool horn 30 is attached to the lower tip of the ultrasonic vibration means 40. A convex part and a concave part are formed on the lower surface of the tool horn 30, and the convex part surface 30a and the concave part bottom surface 30c are connected by a guide surface 30b. In this embodiment, the guide surface 30b is an inclined plane that connects the convex part surface 30a and the concave part bottom surface 30c. Then, a resin molded product 10 is placed on the anvil 50, and a fiber member 20 is placed on the resin molded product 10.

[0028] 1(a), in the state before the welding operation, the tool horn 30 is located at a position above and spaced apart from the resin molded article 10 and the fiber material 20 on the anvil 50. When the welding operation of the ultrasonic welding device of the present invention starts, the actuator 61 of the lifting means 60 descends, and the tool horn 30 ultrasonically vibrates and presses the resin molded article 10 and the fiber material 20 on the anvil 50.

[0029] When the tool horn 30 vibrates ultrasonically and descends toward the resin molded article 10 and fiber material 20 on the anvil 50, the convex surface 30a of the tool horn 30 compresses the fiber material 20, and transmits the ultrasonic vibration to the compressed fiber material 20 and the resin molded article 10 underneath. The direction of the ultrasonic vibration is perpendicular to the convex surface 30a and the bottom surface 30c of the recess of the tool horn 30, that is, the up and down direction in Figures 1(a) and 1(b), and the frequency of the ultrasonic vibration is 20 kHz to 40 kHz, and the amplitude is about several microns to several tens of microns. For reference, small black arrows are shown in the figure to help understand the image of the tool horn 30 vibrating ultrasonically.

[0030] The ultrasonic welding device configured in this manner forms a welding area where the resin molded product 10 and the fiber material 20 are welded, and causes the molten portion of the resin molded product 10, which has been melted on the convex surface 30a of the tool horn 30, to flow from the convex surface 30a of the tool horn 30 toward the concave bottom surface 30c via the guide surface 30b into the concave bottom surface 30c, forming an impregnation area where the molten portion of the resin molded product 10 and the fiber material 20 are entangled, and forming the welding area and the impregnation area adjacent to each other.

[0031] Figures 2(a) to (d) show a transition diagram illustrating how, when the tool horn 30 vibrates ultrasonically and descends toward the resin molded product 10 and fiber material 20 on the anvil 50, the convex surface 30a of the tool horn 30 compresses the fiber material 20 and transmits the ultrasonic vibrations to the compressed fiber material 20 and the resin molded product 10 underneath, forming a welding area and an impregnation area.

[0032] In the state before the welding operation in Fig. 2(a), the tool horn 30 is located at a position above and spaced apart from the resin molded article 10 and the fiber member 20 on the anvil 50. The figure shows that the total thickness (H0) is the sum of the thickness (H1) of the resin molded article 10 and the thickness (H2) of the fiber member 20 before welding.

[0033] 2(b), when the tool horn 30 is ultrasonically vibrated and starts to press the resin molded article 10 and the fiber material 20 on the anvil 50, the convex surface 30a of the tool horn 30 compresses the fiber material 20. FIG 2(b) shows a state where the bottom surface 30c of the recess of the tool horn 30 has reached the surface of the fiber material 20.

[0034] 2(c), when the resin molded product 10 is pushed with the convex surface 30a of the tool horn 30 compressing the fiber material 20, the fiber material 20 and the resin molded product 10 melt. The molten portion of the resin molded product 10 is pushed by the convex surface 30a of the tool horn 30, and flows toward the bottom surface 30c of the recess of the tool horn 30 via the guide surface 30b of the tool horn 30. In other words, the convex surface 30a of the tool horn 30 presses and melts the resin molded product 10, and acts to push up the molten portion of the resin molded product 10 toward the bottom surface 30c of the recess of the tool horn 30 (pumping action).

[0035] In Fig. 2(c), small curved arrows indicate the movement of the molten portion of the resin molded product 10 flowing toward the bottom surface 30c of the recessed portion of the tool horn 30. Fig. 2(c) shows a state in which the amount of the molten portion that the convex surface 30a of the tool horn 30 presses down on the resin molded product 10 and the amount of the molten portion that flows into the bottom surface 30c of the recessed portion of the tool horn 30 are balanced.

[0036] The bottom surface 30c of the recess of the tool horn 30 compresses the fiber material 20, but the amount of compression is less than that of the protruding surface 30a of the tool horn 30, so it accepts the intrusion of the molten portion of the resin molded product 10 that flows in and entangles with the gaps between the fibers of the fiber material 20. The protruding surface 30a, the guide surface 30b, and the bottom surface 30c of the recess of the tool horn 30 are subjected to ultrasonic vibrations of the same period and amplitude, so the protruding surface 30a of the tool horn 30 creates a welded area 11 where the fiber material 20 and the resin molded product 10 are melted together, and the bottom surface 30c of the recess of the tool horn 30 creates an impregnation area 12 where the fiber material 20 and the resin molded product 10 are entangled, that is, where the fiber material 20 is impregnated with the resin molded product 10.

[0037] As shown in Figure 2 (d), when the ultrasonic vibration of the tool horn 30 is stopped and it is moved above the fiber material 20 and the resin molded product 10, the area that the tool horn 30 hits is welded with the welding area 11 and the impregnation area 12 being alternately connected.

[0038] To repeat, Figures 3(a) to (d) show in a transition diagram how the convex surface 30a of the tool horn 30 compresses the fiber material 20 while pushing the resin molded product 10, causing the fiber material 20 and the resin molded product 10 to melt, and the molten portion of the resin molded product 10 is pushed by the convex surface 30a of the tool horn 30, passes through the guide surface 30b of the tool horn 30, and flows toward the bottom surface 30c of the recess in the tool horn 30.

[0039] In FIG. 3(a), the resin molded product 10 melts while the convex surface 30a crushes the fiber member 20, and begins to form a welded area 11. In FIG. 3(b), the convex surface 30a presses down the fiber member 20 and the resin molded product 10, so that a part of the melted resin molded product 10 flows along the inclined surface of the guide surface 30b toward the bottom surface 30c of the recess. When the tool horn 30 is further pressed down, a part of the melted resin molded product 10 flows into the gaps between the fibers of the fiber member 20 facing the bottom surface 30c of the recess, as shown in FIG. 3(c), so that the melted resin molded product 10 becomes entangled with the fiber member 20. When ultrasonic vibration is then applied by the tool horn 30 for a certain period of time, the fiber member 20 that the convex surface 30a is in contact with is welded to the resin molded product 10, as shown in FIG. 3(d). Then, the fiber member 20 that the bottom surface 30c of the recess is in contact with forms an impregnation area 12 in which the melted part of the resin molded product 10 is entangled with the fiber member 20. As shown in Figure 3(e), when the ultrasonic vibration of the tool horn 30 is stopped and the tool horn 30 is moved above the fiber material 20 and the resin molded product 10, the areas that the tool horn 30 hits are welded with the welding areas 11 and the impregnation areas 12 alternately connected.

[0040] 2 and 3, the cross section of the fibrous member 20 is shown with diagonal lines, but to facilitate understanding of the present invention, Fig. 4 illustrates a welding procedure for welding the fibrous member 20 as a filter sheet made of looped fibers to the frame-shaped resin molded product 10. By showing the cross section of the fibrous member 20 with looped lines, the difference in the degree to which the fibrous member 20 is crushed can be intuitively understood.

[0041] That is, in Fig. 4(a), since the tool horn 30 and the fiber material 20 are separated, the fiber material 20 is not crushed and the loop lines are uniformly arranged. As shown in Fig. 4(b), when the convex surface 30a of the tool horn 30 starts to press the fiber material 20, the loop-shaped fiber material 20 that the convex surface 30a contacts is crushed to some extent, but the loop-shaped fiber material 20 that the recess bottom surface 30c contacts is not crushed.

[0042] 4(c), where the convex surface 30a of the tool horn 30 is strongly pushing the fiber material 20, the loop-shaped fiber material 20 that the convex surface 30a is contacting is strongly crushed and begins to melt into the resin molded article 10 that has been subjected to the ultrasonic vibration. Then, the fiber material 20 that the concave bottom surface 30c is contacting receives the molten portion that flows in from the convex surface 30a via the guide surface 30b while maintaining the loop shape of the fibers, and the loop-shaped fiber material 20 and the molten portion of the resin molded article 10 begin to intertwine.

[0043] Thereafter, when ultrasonic vibrations are applied for a certain period of time by the tool horn 30, the looped fiber material 20 that the convex surface 30a contacts is welded to the resin molded product 10 to form a welded area 11. The looped fiber material 20 that the concave bottom surface 30c contacts forms an impregnation area 12 where the molten part of the resin molded product 10 is entangled. This is technically the same as the content explained using Fig. 2, and although this explanation is repeated, the features of the present invention can be more easily understood by looking at Fig. 4.

[0044] 5 shows a plan view of a rectangular sheet of fiber material 20 overlaid on a square frame-shaped resin molded product 10 after applying an ultrasonically vibrating tool horn 30 to the periphery of the rectangular sheet, and welding is performed with welding areas 11 and impregnation areas 12 alternately connected. In the welding area 11, the fiber material 20 and the resin molded product 10 are melted together and strongly welded with a certain welding strength. In the impregnation area 12, the resin molded product 10 is impregnated so as to be entangled with the fiber material 20, and the fiber material 20 and the resin molded product 10 are welded together, although the welding strength is weaker than that of the welding area 11.

[0045] In the conventional welding method described using Figures 24 to 26, the fiber material 20 and the resin molded product 10 are separated between one welding area and another welding area formed at a distance, but in the present invention, an impregnation area is created in which the resin molded product 10 is entangled with the fiber material 20.

[0046] Therefore, the strength of the weld between the fiber member 20 and the resin molded product 10 is increased, and the fiber member 20 and the resin molded product 10 are welded continuously at the points where the tool horn is in contact.

[0047] 1 to 4 do not show the thickness of the tool horn of the ultrasonic welding apparatus of the present invention, so Fig. 6 shows a perspective view of the tool horn 30 seen from below, with the thickness of the tool horn 30 indicated by the symbol "b". In the first embodiment, the thickness "b" of the protruding surface 30a of the tool horn is made smaller than the width "B" of the step portion 10a of the resin molded product 10 that covers the peripheral vicinity portion 21 of the fiber material 20. In Fig. 5, the dimension corresponding to the thickness of the protruding surface 30a of the tool horn is indicated by "b", and the dimension corresponding to the width of the step portion 10a of the resin molded product 10 is indicated by "B".

[0048] The resin molded product 10 in contact with the side surface of the convex surface 30a of the tool horn is not melted, and therefore acts as a wall that prevents the molten portion of the resin molded product from flowing in. Therefore, the molten portion of the resin molded product does not spread in the direction of the side surface of the convex surface 30a of the tool horn, that is, in the thickness direction of the convex surface 30a of the tool horn, but is guided by the guide surface 30b and flows toward the bottom surface 30c of the recess, which is a space.

[0049] (Modification of the first embodiment) If the welding ranges are close to each other and guide surface 30b connecting convex surface 30a and concave bottom surface 30c cannot be made inclined as described in the first embodiment above, a tool horn may be used in which the guide surface of the tool horn is an outwardly convex curved surface instead of an inclined surface, as shown in Fig. 7(a). That is, in the tool horn 31 of Fig. 7(a), guide surface 31b that guides the molten portion from convex surface 31a of tool horn 31 to concave bottom surface 31c is an outwardly convex curved surface.

[0050] In Figure 8 (a), when ultrasonic vibrations are applied to the resin molded product 10 while the convex surface 31a of the tool horn 31 is compressing the fiber material 20, the fiber material 20 and the resin molded product 10 melt, and the molten portion of the resin molded product 10 is pushed by the convex surface 31a of the tool horn 31 and flows toward the bottom surface 31c of the recess of the tool horn 31, via the guide surface 31b of the tool horn 31.

[0051] 8(b) to 8(d), the bottom surface 31c of the recess of the tool horn 31 compresses the fiber material 20, but the amount of compression is less than that of the protruding surface 31a of the tool horn 31, so that the molten portion of the resin molded product 10 that flows in and entangles with the gaps between the fibers of the fiber material 20 is received. The protruding surface 31a, the guide surface 31b, and the bottom surface 31c of the recess of the tool horn 31 are subjected to ultrasonic vibrations of the same period and amplitude, so that the protruding surface 31a of the tool horn 31 creates a welded area 11 where the fiber material 20 and the resin molded product 10 are melted together, and the bottom surface 31c of the recess of the tool horn 31 creates an impregnation area 12 where the fiber material 20 and the resin molded product 10 are entangled, that is, where the fiber material 20 is impregnated with the resin molded product 10. 8(e), when the ultrasonic vibration of the tool horn 31 is stopped and the tool horn 31 is moved above the fiber material 20 and the resin molded product 10, the area where the tool horn 31 hits is welded in a state where the welded areas 11 and the impregnated areas 12 are alternately connected. This is the same as that described with reference to FIGS. 2 and 3.

[0052] In addition, if it is not possible to obtain a large radius R of the curved surface instead of the inclined surface, a slope or curved surface with a small chamfer may be sufficient, and in some cases, it may not be necessary to have a slope or curved surface, as in the tool horn 32 shown in Figure 7(b).

[0053] In the above description, an example is shown in which a frame-shaped resin molded product 10 and a rectangular sheet-shaped fiber member 20 are welded together, but the resin molded product 10 may have a shape other than a frame shape, such as a flat plate, a curved plate, a square timber, or a bar. The resin molded product may not be a hard plate, but may be flexible, such as a plastic sheet. The present invention can be applied to other cases in which a welded area is formed by melting the resin molded product and the fiber member, and at the same time, an impregnated area is formed by entangling and impregnating the two, thereby obtaining high welding strength between the resin molded product and the fiber member and a wide welding area.

[0054] In the first embodiment, a tool horn is used in which a set of convex portions and concave portions, with the convex surface and the concave bottom surface connected by a guide surface, are repeatedly formed in one direction on the pressing surface of the tool horn.

[0055] In the present invention, the welding strength can be increased by repeating the convex and concave portions in which the convex surface and the concave bottom surface are connected by a guide surface. For example, as shown in FIG. 9(a), not only the convex and concave portions in which the convex surface and the concave bottom surface are connected by a guide surface are formed repeatedly in one direction on the pressing surface, but also the convex and concave portions in one direction may be repeated in parallel on the pressing surface as shown in FIG. 9(b), or the convex and concave portions may be repeated in a lattice shape on the pressing surface at a predetermined angle as shown in FIG. 9(c). Also, as shown in FIG. 9(d), the convex and concave portions may be repeated in a radial shape from the inside to the outside of the pressing surface. The most suitable one may be used depending on the required strength.

[0056] In the following, a second embodiment will be described in which the multiple convex portions and concave portions shown in Fig. 9(b) are arranged in parallel on the pressing surface in one direction. In the third embodiment, a third embodiment will be described in which the multiple convex portions and concave portions shown in Fig. 9(c) are arranged in a lattice pattern on the pressing surface at a predetermined angle. In the fourth and fifth embodiments, a fourth embodiment will be described in which the multiple convex portions and concave portions shown in Fig. 9(d) are arranged in a radial pattern from the inside to the outside of the pressing surface.

[0057] Second Embodiment In a second embodiment of the ultrasonic welding apparatus of the present invention, a case will be described in which the tip of the tool horn 70 is a rectangular prism, and the pressing surface of the tool horn has a plurality of convex and concave portions arranged in parallel in one direction.

[0058] Fig. 10(a) is a cross-sectional view of the tip of a tool horn in a second embodiment of the ultrasonic welding device of the present invention, and Fig. 10(b) is a bottom view of the pressing surface of the tool horn. In the tool horn 70 in Fig. 10, the tip is a square prism, and the pressing surface of the tool horn has multiple convex and concave portions arranged in parallel in one direction.

[0059] That is, in Fig. 10(b), the first recess bottom surface 70c-1, the first convex surface 70a-1, the second recess bottom surface 70c-2, the second convex surface 70a-2, the third recess bottom surface 70c-3, the third convex surface 70a-3, and the fourth recess bottom surface 70c-4 are connected by the guide surface 70b as a basic shape, and are arranged in two parallel rows. In Fig. 10(b), the length of the second convex surface 70a-2 is made longer than the first convex surface 70a-1 and the third convex surface 70a-3, so that the welding range 11 corresponding to the second convex surface 70a-2 is made larger. In the second embodiment, the convex portions and the concave portions are repeated in one direction in multiple rows, and a wide range is welded, thereby increasing the welding strength compared to the first embodiment.

[0060] Third embodiment In a third embodiment of the ultrasonic welding apparatus of the present invention, a case is described in which the tip of the tool horn 71 is formed as a rectangular pillar, and convex and concave portions are alternately repeated in one direction on the pressing surface of the tool horn, intersecting at a predetermined angle.

[0061] Fig. 11(a) is a cross-sectional view of the tip of a tool horn in a third embodiment of the ultrasonic welding device of the present invention, and Fig. 11(b) shows a bottom view of the pressing surface of the tool horn. In the tool horn 71 in Fig. 11, the tip is a square prism, and the pressing surface of the tool horn has a plurality of repeated convex and concave portions formed in a lattice pattern that intersect at a predetermined angle.

[0062] In Figure 11(b), the basic form is formed by connecting the first recess bottom surface 71c-1, the first convex surface 71a-1, the second recess bottom surface 71c-2, the second convex surface 71a-2, the third recess bottom surface 71c-3, the third convex surface 71a-3, the fourth recess bottom surface 71c-4, the fourth convex surface 71a-4, and the fifth recess bottom surface 71c-5 with guide surfaces 71b, and the convex portions and concave portions are repeated in a lattice pattern.

[0063] When ultrasonic vibration is applied to the resin molded product 10 while the convex surfaces 71a-1 to 4 of the tool horn 71 compress the fiber material 20, the fiber material 20 and the resin molded product 10 melt, and the melted part of the resin molded product 10 is pushed by the convex surfaces 71a-1 to 4 of the tool horn 71 and flows toward the recessed bottom surfaces 71c-1 to 5 of the tool horn 71 through the guide surface 71b of the tool horn 71, in the same mechanism as described in the first embodiment. As a result, the areas pressed by the convex surfaces 71a-1 to 4 become the welded range 11, and the areas pressed by the recessed bottom surfaces 71c-1 to 5 become the impregnated range 12. In the third embodiment, a wide range is welded. The fiber material 20 and the resin molded product 10 are welded more strongly than in the first and second embodiments.

[0064] (Fourth embodiment) In a fourth embodiment of the ultrasonic welding apparatus of the present invention, a case is described in which a tool horn 72 is used in which the pressing surface of the tool horn is polygonal, and polygonal convex portions and polygonal concave portions, with the convex surface and the concave bottom surface connected by a guide surface, are formed so as to be repeated radially from the inside to the outside of the pressing surface.

[0065] Fig. 12(a) is a cross-sectional view of the tip of a tool horn of a fourth embodiment of the ultrasonic welding device of the present invention, and Fig. 12(b) shows the pressing surface of the tool horn as a bottom view. In the tool horn 72 of Fig. 12, the tip is a square prism, and the pressing surface of the tool horn 72 is a square. In the center of the pressing surface, there is a first convex surface 72a-1 which is a low square prism, and outside of that, there is a first concave bottom surface 72c-1 in the shape of a square frame, and outside of that, there is a second convex surface 72a-2 in the shape of a square frame, and outside of that, there is a second concave bottom surface 72c-2 in the shape of a square frame, and each of the convex surfaces 72a-1, 2 and the concave bottom surfaces 72c-1, 2 are connected by a guide surface 72b.

[0066] The welding procedure of the ultrasonic welding apparatus according to the fourth embodiment of the present invention is substantially the same as the welding procedure of the ultrasonic welding apparatus according to the first embodiment, so a detailed explanation will be omitted. However, FIG. 13 shows an external oblique view of a resin molded product 10 and a fiber material 20 welded by the ultrasonic welding apparatus according to the fourth embodiment of the present invention.

[0067] In Fig. 13, a fiber material 20 is placed on a resin molded product 10, and the fiber material 20 that comes into contact with the convex surfaces 72a-1, 72a-2 of the pressing surface of the tool horn is welded to the resin molded product 10 to form a welded area 11, and on both sides of it, impregnation areas 12 in which the fiber and molten resin are entangled are formed. Fig. 13 shows a case in which four locations are formed in which polygonal welded areas 11 and impregnation areas 12 are repeated radially from the inside to the outside.

[0068] An enlarged perspective view of the welded portion is shown in Fig. 14. A rectangular welded area 11 is formed on the convex surfaces 72a-1 and 2 of the tool horn, and a polygonal impregnation area 12 in which the fiber material 20 and the molten resin molded product 10 are intertwined is formed radially and repeatedly on the bottom surfaces 72c-1 and 2 of the concave portion. Therefore, the weld strength between the fiber material 20 and the resin molded product 10 is increased compared to the first to third embodiments, making it difficult to peel off.

[0069] (Modification of the fourth embodiment) 15 shows a cross-sectional view of the tip of tool horn 73 according to a modified example of the ultrasonic welding device of the present invention. Tool horn 73 has a shape in which the positions of the convex and concave parts of tool horn 72 described in FIG.

[0070] The tip of tool horn 73 is a square prism, and at the centre of the square that is the pressing surface is a square first recessed bottom surface 73c-1, outside which is a square frame-shaped first convex surface 73a-1, and outside of that is a square frame-shaped second recessed bottom surface 73c-2, outside of which is a square frame-shaped second convex surface 73a-2, with guide surfaces 73b connecting between the respective convex and concave portions.

[0071] Fig. 16 shows an enlarged perspective view of the portion welded by the tool horn 73. In the tool horn 73 according to the modified example of the fourth embodiment shown in Fig. 15, the welded area 11 is formed on the convex surface 73a-1, 2 of the pressing surface, and the impregnated area 12 in which the fiber and the molten resin are entangled is formed radially from the inside to the outside of the pressing surface on the bottom surface 73c-1, 2 of the recess. The welded area 11 and the impregnated area 12 in which the fiber and the resin are entangled are formed repeatedly radially, so that the weld strength between the fiber material 20 and the resin molded product 10 is increased and they are less likely to peel off. This is the same as in the fourth embodiment.

[0072] Fifth embodiment In the fifth embodiment, a case is described in which a tool horn 81 is used in which the tip of the tool horn 81 is cylindrical, and concentric convex portions 81a and concentric concave portions 81c are repeatedly formed radially from the inside to the outside of the circle which is the pressing surface of the tool horn 81, with the convex surface and the concave bottom surface connected by a guide surface.

[0073] In the fifth embodiment, the convex surface 81a and the recess bottom surface 81c-1, 2 are connected by guide surfaces 81b-1, 2 to form adjacent concentric convex and recessed portions, and the convex surface 81a of the ultrasonically vibrating tool horn 81 presses the fiber material 20 and the resin molded product 10 to form a welded area where the two are welded together, and the molten portion of the resin molded product 10 melted on the convex surface 81a of the tool horn 81 is caused to flow from the convex surface 81a of the tool horn 81 toward the recess bottom surfaces 81c-1, 2 using the guide surfaces 81b-1, 2 to form an impregnation area 12 where the molten portion of the resin molded product 10 and the fiber material 20 are entangled, and the welded area 11 and the impregnation area 12 are formed adjacent to each other.

[0074] Fig. 17(a) shows a cross-sectional view of the tip of a tool horn 81 of a fifth embodiment of the ultrasonic welding device of the present invention, and Fig. 17(b) shows a bottom view of the pressing surface of the tool horn 81. Also, Fig. 18 shows an external perspective view of the tool horn 81 as seen obliquely from below.

[0075] As shown in Figures 17(a)(b) and 18, the circular pressing surface of tool horn 81 is formed, from the center to the outer periphery, with a first recess bottom surface 81c-1, a first guide surface 81b-1, a convex surface 81a, a second guide surface 81b-2, and a second recess bottom surface 81c-2.

[0076] 19(a), 19(b), 19(c), and 19(d) are cross-sectional views showing the welding procedure of the ultrasonic welding device according to the fifth embodiment of the present invention. Note that FIG. 19 corresponds to FIG. 4 used in the explanation of the first embodiment.

[0077] In Fig. 19(a), the tool horn 81 and the fiber material 20 are separated, so the fiber material 20 is not crushed and the loop lines are uniformly arranged. As shown in Fig. 19(b), when the convex surface 81a of the tool horn 81 starts to press the fiber material 20, the loop-shaped fiber material 20 that the convex surface 81a is in contact with is crushed to some extent, but the loop-shaped fiber material 20 that the recess bottom surfaces 81c-1, 81c-2 are in contact with is not crushed.

[0078] 19(c), where the convex surface 85a of the tool horn 81 is strongly pushing the fiber material 20, the loop-shaped fiber material 20 that the convex surface 81a is contacting is strongly crushed and begins to melt into the resin molded article 10 that has been subjected to the ultrasonic vibrations. Then, the fiber material 20 that was contacting the recess bottom surfaces 81c-1, 2 receives the molten portion that flows in from the convex surface 81a via the guide surfaces 81b-1, 2 while maintaining the loop shape of the fibers, and the loop-shaped fiber material 20 and the molten portion of the resin molded article 10 begin to intertwine.

[0079] Thereafter, when ultrasonic vibrations are applied for a certain period of time by the tool horn 81, the loop-shaped fiber material 20 that has been in contact with the convex surface 81a is welded to the resin molded product 10 to form a welded area 11. The loop-shaped fiber material 20 that has been in contact with the concave bottom surfaces 81c-1, 81c-2 forms an impregnation area 12 where the molten part of the resin molded product 10 is entangled.

[0080] 20 shows an external perspective view of a structure welded using tool horn 81 of the fifth embodiment of the ultrasonic welding device of the present invention. There is impregnation area 12 where fibers and resin are entangled as a circular convex part in the center, and outside of that there is welded area 11 as a concentric concave part, and outside of that there is impregnation area 12 where fibers and resin are entangled as a circular convex part.

[0081] The convex portion 81a of the pressing surface forms the welding area 11, and the concave portions 81c-1 and 81c-2 form the impregnation area 12 where the fiber and the molten resin are entangled, and these are repeatedly formed radially from the inside of the pressing surface to the outside. Since the welding area 11 and the impregnation area 12 where the fiber and the resin are entangled are repeatedly formed radially, the welding strength between the fiber material 20 and the resin molded product 10 is high and they are not easily peeled off. This effect is the same as that of the fourth embodiment.

[0082] (First modified example of the fifth embodiment) Fig. 21(a) shows a cross-sectional view of the tip of tool horn 82 as a first modified example of the fifth embodiment of the ultrasonic welding apparatus of the present invention, and Fig. 21(b) shows a bottom view of the pressing surface of tool horn 82. In the first modified example of the fifth embodiment, the circular pressing surface of tool horn 82 is formed with a first recess bottom surface 82c-1, a first guide surface 82b-1, a first convex surface 82a-1, a second guide surface 82b-2, a second recess bottom surface 82c-2, a third guide surface 82b-3, a second convex surface 82a-2, a fourth guide surface 82b-4, and a third recess bottom surface 82c-3 from the inside to the outer periphery.

[0083] Since the welded area 11 and the impregnated area 12 where the fiber and the resin are intertwined are repeatedly formed radially from the inside to the outside, the weld strength between the fiber material 20 and the resin molded product 10 is increased and they are less likely to come apart. This effect is the same as that of the fifth embodiment.

[0084] (Second Modification of the Fifth Embodiment) Fig. 22(a) shows a cross-sectional view of the tip of tool horn 83 as a second modified example of the fifth embodiment of the ultrasonic welding apparatus of the present invention, and Fig. 22(b) shows a bottom view of the pressing surface of tool horn 83. In the second modified example of the fifth embodiment, the circular pressing surface of tool horn 83 is formed with, from the inside to the outer periphery, a first convex surface 83a-1, a first guide surface 83b-1, a first recessed bottom surface 83c-1, a second guide surface 83-2, a second convex surface 83a-2, a third guide surface 83b-3, and a second recessed bottom surface 83c-2.

[0085] Since the welded area 11 and the impregnated area 12 where the fiber and the resin are intertwined are formed repeatedly in a radial pattern, the weld strength between the fiber material 20 and the resin molded product 10 is increased, making them less likely to come apart. This effect is the same as in the fifth embodiment.

[0086] (Third Modification of the Fifth Embodiment) In a third modified example of the fifth embodiment of the ultrasonic welding apparatus of the present invention, as shown in Figures 23(a) and (b), the circular pressing surface of the tool horn 84 is formed, from the inside to the outer periphery, with a first convex surface 84a-1, a first concave bottom surface 84c-1, a second convex surface 84a-2, a second concave bottom surface 84c-2, a third convex surface 84a-3, and a third concave bottom surface 84c-3, which connect the convex surface and the concave bottom surface with guide surfaces.

[0087] The first convex surface 84a-1, the second convex surface 84a-2, and the third convex surface 84a-3 have fine iris (knurled) irregularities to increase the surface area.

[0088] The height from the bottom of the recess to the surface of the protrusion provided on the pressing surface may be the same for the first protrusion surface 84a-1, the second protrusion surface 84a-2, etc., or may be different. The height from the bottom of the recess to the surface of the protrusion is arbitrary.

[0089] Since the welded area 11 and the impregnated area 12 where the fiber and the resin are intertwined are formed repeatedly in a radial pattern, the weld strength between the fiber material 20 and the resin molded product 10 is increased, making them less likely to come apart. This effect is the same as in the fifth embodiment. [Industrial Applicability]

[0090] The present invention can be widely applied to ultrasonic welding devices that weld fiber members to resin molded products, and in particular, can be applied to ultrasonic welding devices that strongly weld fiber members made of fiber materials such as medical filters and sludge treatment membranes so that they do not peel off from the resin molded product. [Explanation of symbols]

[0091] 10 Resin molded products 11 Welding range 12 Impregnation range 20 Fiber materials 30 Tool Horn 30a Convex surface 30b Guide surface 30c Bottom of recess 40 Ultrasonic vibration means 50 Anvil 51 Frames 60 Tool horn lifting means

Claims

[Claim 1] 1. An ultrasonic welding apparatus for welding a fiber material and a resin molded product by placing a fiber material on a resin molded product placed on an anvil and pressing a tool horn that is ultrasonically vibrating from a surface of the fiber material against the fiber material and the resin molded product, comprising: a convex portion and a concave portion are formed adjacent to each other on the pressing surface of the tool horn, the convex portion having a surface and a concave portion having a bottom surface connected by a guide surface; pressing the fiber material and the resin molded product with a convex portion of the ultrasonically vibrating tool horn to form a welded area where the two are welded together; A molten portion of the resin molded product melted at the convex portion of the tool horn is caused to flow from a surface of the convex portion of the tool horn toward a bottom surface of the concave portion, thereby forming an impregnation area in which the molten portion of the resin molded product and the fiber member are entangled with each other; An ultrasonic welding apparatus configured to form the weld area and the impregnation area adjacent to each other.

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