JP2023111424A - Method for manufacturing structure body - Google Patents

Abstract

To suppress occurrence of an appearance defect in a structure body that is an object to be processed.SOLUTION: There is provided a method for manufacturing a structure body, which comprises an ultrasonic welding process. The structure body comprises first and second members, in which the first member is a member made of solid resin, and the second member is a member made of foamed resin. In the ultrasonic welding process, a horn is pressed against the first member arranged so as to be in contact with the second member to ultrasonically weld the first and second members, in which the horn has a spike portion and a base portion, in which the spike portion is formed to taper in a direction in which the horn is pressed against the first member, and provided on a tip side of the base portion.SELECTED DRAWING: Figure 1

Description

The present invention relates to a structure manufacturing method.

Patent Literature 1 discloses a method of connecting metal members by deforming the metal members so as to expand the diameter of the metal members.

JP-A-2007-275932

If the resin member is deformed as in Patent Document 1, it will be damaged. Therefore, when connecting the resin members, for example, a method using a hot-melt adhesive is conceivable. However, in the method using a hot-melt adhesive, it is necessary to properly handle the fluid adhesive. That is, in this method, it is necessary to apply the adhesive to the desired position of the resin members so that the adhesive does not protrude into the non-connected portions, and there is a problem that the burden of the process of connecting the resin members increases. .

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the work load of connecting members made of resin.

According to the present invention, there is provided a structure manufacturing method including an ultrasonic welding step, wherein the structure includes first and second members, and the first member is a member made of solid resin. and the second member is a member made of foamed resin, and in the ultrasonic welding step, the horn is pressed against the first member arranged so as to be in contact with the second member to form the first and second Two members are ultrasonically welded together, the horn has a spike portion and a base portion, the spike portion is formed to taper in a direction in which the horn is pressed against the first member, and the base portion A method is provided that is provided distally.

In the present invention, the first and second members can be ultrasonically welded to connect the first and second members by pressing the horn against the first member arranged so as to contact the second member; Work load for connecting the first and second members can be suppressed.

Various embodiments of the present invention are illustrated below. The embodiments shown below can be combined with each other.
Preferably, the first member has a thin wall portion and a thick wall portion, the thin wall portion is connected to the thick wall portion and is thinner than the thick wall portion, and the ultrasonic welding step , the horn is pressed against the thinned portion.
Preferably, the first member has a recess, the recess has a bottom surface and an inner surface, the bottom surface is formed in the thin portion, and the inner surface is formed to stand on the bottom surface. and a slanted surface is formed on the inner surface, and the slanted surface is slanted from the thick portion side to the bottom surface side.
Preferably, the horn has at least three or more spikes, and the spikes are concentrically arranged.

FIG. 1 is a schematic diagram showing a schematic configuration of an ultrasonic welding device 100 according to an embodiment. 2A is a perspective view of the vibration transmitting portion 2 of the horn 1. FIG. FIG. 2B is a front view of the vibration transmitting section 2 shown in FIG. 2A. FIG. 2C is a bottom view of the vibration transmitting portion 2 shown in FIG. 2A. FIG. 3 is a perspective view of the structure 10 (the structure after ultrasonic welding has been completed). 4A is an enlarged view of area A shown in FIG. 3. FIG. FIG. 4B is a cross-sectional view along dashed line BB shown in FIG. 4A. FIG. 5 is a perspective view of the first member 11 (the first member before ultrasonic welding). FIG. 6 is a cross-sectional view showing a state in which the placement step of the manufacturing method of the structure 10 according to the embodiment is completed. In FIG. 6, the placement table 8 is omitted from the illustration. FIG. 7 shows that in the ultrasonic welding step of the method for manufacturing the structure 10 according to the embodiment, the horn 1 is pushed into the first member 11 after the horn 1 is brought into contact with the first member 11, and the second member 12 is pushed in the thickness direction. It shows a compressed state. FIG. 8 shows a state in which the spike portion 2b penetrates the first member 11 up to the root portion 2b1 in the ultrasonic welding process. FIG. 9 shows a state in which the horn 1 shown in FIG. 8 is retracted from the first member 11 in the retraction step of the manufacturing method of the structure 10 according to the embodiment. FIG. 10A is a perspective view of a vibration transmitting portion 2 according to a modification. 10B is a side view of the vibration transmitting portion 2 shown in FIG. 10A. FIG. 10C is a front view of the vibration transmitting portion 2 shown in 10A.

Embodiments of the present invention will be described below. Various features shown in the embodiments shown below can be combined with each other.

1. Description of Configuration of Ultrasonic Welding Apparatus 100 As shown in FIG. A pressure mechanism 7 , a placement table 8 , and a holding portion 9 are provided. The ultrasonic welding apparatus 100 also includes a control device (not shown) that controls the oscillator 5 and the pressure mechanism 7 . The ultrasonic welding apparatus 100 can ultrasonically weld the first and second members 11 and 12 to manufacture the structure 10 as shown in FIG. The first member 11 is a member made of solid resin, and the second member 12 is a member made of foamed resin.

1-1. Horn 1
The horn 1 is a tool for transmitting vibration transmitted from the vibrator 4 to the first and second members 11 and 12 and welding the first and second members 11 and 12 . The horn 1 is provided so as to protrude from the holding portion 9 . The upper end portion side of the horn 1 is fixed within the holding portion 9 . The horn 1 is made of, for example, a metal material. Aluminum, iron, titanium, and the like, for example, can be used as the metal material.

1-1-1. Vibration transmission part 2
As shown in FIGS. 1 and 2A to 2C, the vibration transmitting portion 2 is a rod-shaped member, and its upper end is connected to the connecting portion 3. As shown in FIG. The vibration transmission part 2 can be manufactured by processing a metal member with an NC (numerical control) processing machine, for example. Vibration of the vibrator 4 is transmitted to the vibration transmitting section 2 via the connecting section 3 . The vibration transmitting portion 2 includes a base portion 2a and a spike portion 2b. The vibration transmitting portion 2 includes a plurality of (four in the embodiment) spike portions 2b. Although the embodiment describes an example in which the vibration transmitting portion 2 includes four spike portions 2b, the present invention is not limited to this. For example, by providing the vibration transmitting section 2 with three or more spikes 2b, it is possible to suppress the inclination of the first member 11 when the spikes 2b are pressed against the first member 11. can.

<Base 2a>
As shown in FIG. 2A, the base portion 2a has a columnar portion 2a1 and an end surface portion 2a2. The columnar portion 2a1 is formed in a cylindrical shape, and an end surface portion 2a2 is formed on the tip side thereof. The end surface portion 2a2 is provided with four spike portions 2b, which are flat surfaces in the embodiment. As shown in FIG. 2A, an annular tapered surface 2a11 is formed on the edge of the tip of the columnar portion 2a1. Specifically, the diameter R1 (mm) of the columnar portion 2a1 shown in FIG. , 22, 23, 24, 25, 26, 27, 28, 29, 30, and may be in the range between any two of the values exemplified herein.

<Spike portion 2b>
As shown in FIGS. 2A to 2C, the spike portion 2b is tapered in the direction in which the horn 1 is pressed against the first member 11. As shown in FIGS. The spike portion 2b is provided on the tip side (end face portion 2a2) of the base portion 2a. As shown in FIG. 2C, the vibration transmitting portion 2 has a centrally arranged spike portion 2b and three spike portions 2b arranged so as to surround the spike portion 2b. As shown in FIGS. 2B and 2C, the three spikes 2b are arranged such that the positions Ot corresponding to the tops 2b2 form a triangle (an equilateral triangle in the embodiment). The positions Ot corresponding to the tops 2b2 of the three spikes 2b are arranged concentrically. A position O corresponding to the top 2b2 of the central spike 2b is arranged so as to coincide with the center of gravity of the triangle formed by the positions Ot of the three spikes 2b. In other words, the length between position O and each position Ot is equal. If the vibration transmitting portion 2 has only three spike portions 2b, the central spike portion 2b may be omitted.

As shown in FIGS. 2A and 2B, the spike portion 2b is formed in a conical shape. Spike portion 2b has root portion 2b1, top portion 2b2, and side portion 2b3. Specifically, the height width h (mm) of the spike portion 2b shown in FIG. 2B is 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0 , 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, and any of the numerical values exemplified here or within a range between the two.

Root portion 2b1 is connected to end face portion 2a2 and is formed in an annular shape. Here, the width R2 (mm) of the root portion 2b1 (spike portion 2b) shown in FIG. .5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, where may be within a range between any two of the numerical values exemplified in .

Top portion 2b2 is formed at the tip of spike portion 2b. Specifically, the angle θ (degrees) of the top portion 2b2 shown in FIG. 85, 90, 95, 100, 105, 110, 115, 120, and may be in the range between any two of the numbers exemplified herein. The angle θ (degrees) of the top portion 2b2 corresponds to the angle between the side portions 2b3 when the spike portion 2b is viewed in a vertical section passing through the top portion 2b2.

Side portion 2b3 is formed from root portion 2b1 to top portion 2b2. The side surface portion 2b3 is tapered in the direction of pressing the horn 1 against the first member 11, and is conical in the embodiment.

1-1-2. Connection part 3
The connecting portion 3 has a function of increasing the amplitude of the vibration of the vibrator 4 when transmitting the vibration to the horn 1 . The connecting portion 3 is a rod-shaped member, the lower portion of the connecting portion 3 is provided in the vibration transmitting portion 2 , and the upper portion of the connecting portion 3 is accommodated in the holding portion 9 together with the vibrator 4 .

1-2. Vibrator 4
The vibrator 4 is configured to vibrate with power supplied from the oscillator 5 . The vibrator 4 can be composed of, for example, an electrostrictive piezoelectric ceramic vibrator or the like.

1-3. cable 6 and oscillator 5
The oscillator 5 supplies the vibrator 4 with power of a frequency related to ultrasonic waves through the cable 6 .

1-4. Pressure mechanism 7 and holding part 9
The pressure mechanism 7 is configured to be able to move the holding portion 9 in a predetermined direction. The pressurizing mechanism 7 can be composed of, for example, a motor, a mechanism for moving the holding portion 9 by the power of the motor, or the like. The predetermined direction is the direction from the side of the holding part 9 to the side of the placement table 8, which is the vertical direction in the embodiment. Since the vibrator 4 and the horn 1 are directly or indirectly held by the holding portion 9 , the horn 1 moves together with the holding portion 9 when the holding portion 9 is moved by the pressing mechanism 7 .

1-5. placement table 8
The placement table 8 is a table for placing the second member 12 . The pressure mechanism 7 is fixed by connecting the lower end of the pressure mechanism 7 to the placement table 8, but the pressure mechanism 7 may be fixed to other locations.

2. Description of Configuration of Structure 10 As shown in FIG. 3 , the structure 10 manufactured by the manufacturing method according to the embodiment includes first and second members 11 and 12 . The structure 10 is configured by fixing the first member 11 to the second member 12 by welding the first member 11 to the second member 12 by ultrasonic welding. As shown in FIG. 4A, the structure 10 is formed with a concave portion 11C. The concave portion 11C is formed by pressing the spike portion 2b of the horn 1 against the first member 11 during ultrasonic welding.

2-1. First member 11
The first member 11 is a member made of solid resin, and the resin making up the first member 11 can be made of, for example, polypropylene. In addition, the resin constituting the first member 11 is not limited to polypropylene, and can be composed of, for example, a resin composition containing a thermoplastic resin such as polyolefin. Polyolefins include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymers and mixtures thereof.

As shown in FIG. 3, the first member 11 has a body portion 11a and a plurality of (three in the embodiment) fixing portions 11b. In addition, although the example provided with several fixing|fixed part 11b is shown in embodiment, it is not limited to this, One may be sufficient.

2-1-1. Body portion 11a
The shape and function of the body portion 11a are not particularly limited, but in the embodiment, the body portion 11a is a portion corresponding to a retainer, which is a component that constitutes the back door trim of the vehicle. The body portion 11a is connected to the fixed portion 11b and is provided so as to protrude from the fixed portion 11b.

2-1-2. Fixed portion 11b
As shown in FIGS. 4A to 5, the fixing portion 11b is configured in a plate shape. The fixed portion 11b has a thin portion 11A and a thick portion 11B. A recess 11b1 is formed in the fixed portion 11b.

<Thin portion 11A>
As shown in FIG. 4B, the thin portion 11A is connected to the thick portion 11B, and the thickness t2 of the thin portion 11A is thinner than the thickness t1 of the thick portion 11B. The thin portion 11A and the thick portion 11B are arranged on the second member 12 . In the embodiment, the entire thin portion 11A and the entire thick portion 11B are in contact with the second member 12, but the present invention is not limited to such a form. For example, the thin portion 11A may be in contact with the second member only in the area to be welded by the ultrasonic welding apparatus 100, and may be non-contact in other areas (other areas). A part of the thick portion 11B may be in contact with the second member 12, or the entire thick portion 11B may be out of contact with the second member 12.

The thickness t2 of the thin portion 11A shown in FIG. 4B is preferably smaller than the height width h of the spike portion 2b shown in FIG. 2B. Thus, when the horn 1 is pressed against the thin portion 11A and ultrasonic welding is performed, the thin portion 11A is melted by heat and the spike portion 2b not only pierces the thin portion 11A but also the second member 12.例文帳に追加As a result, the resin forming the thin portion 11A enters the second member 12, and the first and second members 11 and 12 are strongly welded by the anchor effect.
Specifically, the thickness t2 (mm) of the thin portion 11A shown in FIG. .8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0 , 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3 .3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5 , 4.6, 4.7, 4.8, 4.9, 5.0, and may be in the range between any two of the values exemplified herein.

In the manufacturing method according to the embodiment, since the fixed portion 1b is formed with the thin portion 11A, appropriate ultrasonic welding can be performed with a small output and in a short time. In addition, in the manufacturing method according to the embodiment, since the thin portion 11A is partially formed in the fixing portion 1b, it is possible to suppress the rigidity of the first member 11 from decreasing.

<Thick portion 11B>
As shown in FIGS. 4A and 4B, the thick portion 11B is arranged to surround the thin portion 11A in the embodiment. The thickness t1 of the thick portion 11B is, for example, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3. 5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0 times, and may be within a range between any two of the numerical values exemplified here.

<Recessed portion 11b1>
Although the concave portion 11b1 is formed in a circular shape in the embodiment, it is not limited to this, and may be, for example, an n-sided shape (where n is an integer of 3 or more). The recess 11b1 has an inner surface 11b2 and a bottom surface 11b3.

As shown in FIGS. 4A and 4B, the inner surface 11b2 is formed to stand on the bottom surface 11b3. Moreover, the inner surface 11b2 is formed in an annular shape. Further, an inclined surface Sr is formed on the inner surface 11b2. The inclined surface Sr is inclined from the upper surface side of the thick portion 11B to the bottom surface 11b3 side. In addition, although the inclined surface Sr is formed on the entire inner surface 11b2 in the embodiment, it is not limited to this, and the inclined surface Sr may be formed on a part of the inner surface 11b2. Specifically, the inclination angle α (degrees) of the inclined surface Sr shown in FIG. It may be in a range between any two of the numerical values given. For example, when the inner surface 11b2 is connected to the bottom surface 11b3 so as to form an angle of 90 degrees, if the horn 1 hits the bottom surface 11b3 during ultrasonic welding, the connection between the inner surface 11b2 and the bottom surface 11b3 is likely to be damaged. On the other hand, in the embodiment, since the inner surface 11b2 is formed with the inclined surface Sr, it is possible to suppress the breakage of the connecting portion between the inner surface 11b2 and the bottom surface 11b3 during ultrasonic welding.

In the embodiment, the inclined surface Sr is described as being a surface forming a constant angle, but it is not limited to this, and may be formed in an arc shape so as to be convex downward. good. At this time, the radius (mm) of this arc is specifically, for example, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, and may be in the range between any two of the values exemplified herein.

A bottom surface 11b3 of the recess 11b1 is the top surface of the thin portion 11A. The bottom surface 11b3 is a circular flat surface in the embodiment. The spike portion 2b of the horn 1 is pressed against the bottom surface 11b3. The diameter r (mm) of the bottom surface 11b3 shown in FIG. 5 is preferably equal to the diameter R1 (mm)+x (mm) of the columnar portion 2a1. Here, x (mm) is specifically for example 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 and may be in the range between any two of the numerical values exemplified here.

2-2. Second member 12
The second member 12 is a member made of foamed resin, and the resin making up the second member 12 can be made of, for example, polypropylene. The foaming agent for the foamed resin is not particularly limited, but for example, a physical foaming agent, a chemical foaming agent, a mixture thereof, or the like can be used. In addition, the resin constituting the second member 12 is not limited to polypropylene, and may be composed of, for example, a resin composition containing a thermoplastic resin such as polyolefin. Polyolefins include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymers and mixtures thereof. Specifically, the expansion ratio (fold) of the foamed resin forming the second member 12 is, for example, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5. , 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, exemplified here It may be in a range between any two of the numbers given.

The thickness T1 of the second member 12 shown in FIG. 4B is preferably greater than the height width h of the spike portion 2b shown in FIG. 2B. As a result, it is possible to prevent the spike portion 2b from penetrating the second member 12 when the horn 1 is pushed into the first member 11 during ultrasonic welding. Specifically, the ratio (T1/h) of the thickness T1 of the second member 12 to the height width h of the spike portion 2b is 1.2, 1.3, 1.4, 1.5, 1.6. , 1.7, 1.8, 1.9, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 and may be in the range between any two of the numerical values exemplified here. Further, the thickness t2 of the thin portion 11A is, for example, twice or more, preferably three times or more, the thickness T1 of the second member 12. As shown in FIG.

3. Method for manufacturing a structure The method includes an arrangement step and an ultrasonic welding step. Each step will be described below.

2-1. Placement Step In the placement step, the second member 12 is placed on the placement table 8 . After that, as shown in FIG. 6, the first member 11 is arranged on the second member 12 . In the embodiment, the horn 1 of the ultrasonic welding device 100 is movable in the vertical direction, and the placement table 8 and the second member 12 are arranged parallel to the horizontal plane. However, the present invention is limited to this. not a thing For example, the horn 1 may be movable in the horizontal direction, and the placement table 8 and the second member 12 may be arranged parallel to a plane perpendicular to the horizontal plane. In this case, it is preferable to provide means for fixing the second member 12 to the placement table 8 and means for fixing the first member 11 to the second member 12 .

2-2. Ultrasonic Welding Process In the ultrasonic welding process, the oscillator 5 is driven to vibrate the horn 1 . Note that the start of driving the oscillator 5 may be performed in the placement process. Subsequently, the horn 1 is moved downward, and the spike portion 2b of the horn 1 is pressed against the thin portion 11A of the first member 11 as shown in FIG. Here, by controlling the pressurizing mechanism 7, the spike portion 2b presses the thin portion 11A downward, and the second member 12 made of foamed resin is pressurized and compressed. Specifically, as shown in FIG. 7, the thickness of the second member 12 changes from the thickness T1 in the placement step to the thickness T2 in the ultrasonic welding step. That is, the amount of compression D can be expressed as thickness T1-thickness T2. It should be noted that the overall thickness of the second member 12 need not be reduced when the second member 12 is compressed. For example, the thickness of the portion of the second member 12 disposed under the thin portion 11A changes from the thickness T1 to the thickness T2.

Specifically, the amount of compression D (mm) is, for example, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, and may be in the range between any two of the numbers exemplified herein.
The ratio (D/T1) of the amount of compression D to the thickness T1 of the second member 12 preferably satisfies 0.1≤D/T1≤0.5, preferably 0.2≤D/T1≤0. It is even more preferable to satisfy the relationship of 44.

In the ultrasonic welding process, it is preferable that the compression amount D is maintained after the second member 12 is compressed to the thickness T2 until the horn 1 moves upward and retreats, but is limited to this. isn't it. The amount of compression D may decrease during the period from when the second member 12 is compressed to the thickness T2 to when the horn 1 moves upward and retreats.

Frictional heat is generated between the first member 11 and the second member 12 by transmitting vibration from the spike portion 2b to the first and second members 11 and 12 . As a result, as shown in FIG. 8, the thin portion 11A melts, and the spike portion 2b enters the thin portion 11A and further enters and pierces the second member 12. As shown in FIG.

After that, as shown in FIG. 9 , the horn 1 is moved upward to retract the horn 1 from the first member 11 . When the horn 1 is retracted from the first member 11, the first and second members 11 and 12 are formed with a mortar-shaped concave portion 11C. In the embodiment, since the first member 11 has three fixed portions 11b, the second member 12 is moved to repeat the above-described operation for the two fixed portions 11b. The structure 10 can be manufactured by completing the ultrasonic welding of the three fixing portions 11b.

3. Functions and effects of the embodiment In the manufacturing method according to the embodiment, the first and second members 11 and 12 are ultrasonically welded by pressing the horn 1 against the first member 11 arranged so as to be in contact with the second member 12. can be used to connect the first and second members 11 and 12 . That is, the first and second members 11 and 12 can be connected by a simple operation of pressing the horn 1 against the first member 11, and the burden of the connection work of the first and second members 11 and 12 is suppressed. be able to.

In the manufacturing method according to the embodiment, the spike portion 2b pierces not only the thin portion 11A but also the second member 12 so as to enter the structure 10, thereby forming the concave portion 11C. For this reason, the resin forming the thin portion 11A enters the second member 12, and the first and second members 11 and 12 are strongly welded by the anchor effect.

Since the first member 11 is a solid resin member, it is less likely to melt than the second member 12, which is foamed resin. Therefore, when the thickness of the portion of the first member 11 against which the horn 1 is pressed is large, the operator tends to increase the output of the oscillator 5 too much or press the horn 1 against the first member 11 in an attempt to secure welding strength. It may take too long. As a result, the second member 12, which is easier to melt than the first member 11, melts excessively, and the lower surface of the second member 12 (the surface opposite to the surface on which the first member 11 is arranged) has a poor appearance. Trouble may occur. If the operator lowers the output of the oscillator 5 in order to avoid such a problem, the welding strength may not be obtained.
In the manufacturing method according to the embodiment, ultrasonic welding is performed by pressing the horn 1 against the thin portion 11A instead of the thick portion 11B. Therefore, when the horn 1 is pressed against the thin portion 11A, the thin portion 11A melts smoothly, the spike portion 2b smoothly pierces the second member 12, and the thin portion 11A and the second member 12 are quickly separated. ultrasonically welded. Therefore, in the manufacturing method according to the embodiment, the output of the oscillator 5 and the time for pressing the horn 1 against the first member 11 can be reduced, and the occurrence of defects on the lower surface of the second member 12 can be suppressed. can be done. In addition, in the manufacturing method according to the embodiment, the thin portion 11A melts smoothly, so it is possible to prevent the welding strength from being lost.

In the manufacturing method according to the embodiment, as described above, the output of the oscillator 5 can be reduced during ultrasonic welding, so it is possible to suppress the generation of burrs due to excessive melting of the resin. Further, in the manufacturing method according to the embodiment, as described above, the time for pressing the horn 1 against the first member 11 during ultrasonic welding can be reduced, so the welding cycle can be shortened.

In addition, since the first member 11 has the thin portion 11A (the concave portion 11b1), the first member is partially thinned. Therefore, in the manufacturing method according to the embodiment, it is possible to suppress a decrease in rigidity of the first member 11 . In addition, if the entire fixed portion 11b is a thin portion, not only the rigidity of the first member 11 is lowered, but also the first member 11 may be warped during molding. In the manufacturing method according to the embodiment, since the first member is partially thinned, warping during molding of the first member 11 can be suppressed.

4. Examples and Comparative Examples 4-1. Amount of Compression D It was confirmed whether a defect or the like occurred in the structure 10 according to the amount of compression D, and whether the welding strength of the structure 10 was sufficiently ensured. The amount of compression D was verified with four patterns of 0.6 mm, 1.0 mm, 1.3 mm, and 1.5 mm. Other conditions are as follows.

Ultrasonic output (output of oscillator 5): 25J
Diameter R1 (mm) of columnar portion 2a1 of horn 1: 10 mm
Width R2 of spike portion 2b of horn 1: 2 mm
Height width h of spike portion 2b of horn 1: 2 mm
Diameter r (mm) of bottom surface 11b3: 20 mm
Thickness t2 of thin portion 11A of first member 11: 1 mm
Thickness T1 of thickness T1 of second member 12: 3 mm

When the amount of compression D was 0.6 mm, 1.0 mm, and 1.3 mm, no appearance defects were observed. On the other hand, when the amount of compression D was 1.5 mm, ten sets of the first and second members 11 and 12 were ultrasonically welded. In the second member 12, the luster of the second member 12 was lost, and the appearance was poor. Ultrasonic welding can be performed even when the amount of compression D is 1.5 mm, but by increasing the amount of compression D, it is possible to more effectively suppress the occurrence of poor appearance.
A tensile test (test speed: 50 mm/min) was performed on the first member 11 welded to the second member 12 when the amount of compression D was 1.0 mm and 1.3 mm. The testing machine used is a TENSILON universal testing machine. As a result of the test, in both cases, it was confirmed that the maximum point load when separating the first member 11 from the second member 12 was 200 N or more, and sufficient welding strength was secured.

4-2. Horn without spike 2b It was confirmed whether appropriate ultrasonic welding was performed when the first and second members 11 and 12 were ultrasonically welded using a horn without spike 2b. In addition, the tip portion of the horn without the spike portion 2b is composed of the flat end face portion 2a2. Ten pairs of first and second members 11 and 12 were subjected to ultrasonic welding using a horn that did not have spike portion 2b. was overheated and the lower surface of the second member 12 was melted, resulting in a defective appearance of the second member 12 .

5. MODIFIED EXAMPLE In the embodiment, the horn 1 has the conical spike portion 2b, but the present invention is not limited to this. As shown in FIGS. 10A to 10C, the top portion 2b2 may be formed to extend linearly. In addition, in this modified example, three spike portions 2b are provided.
The direction in which top portion 2b2 extends is perpendicular to the direction parallel to the axial direction of base portion 2a. Root portion 2b1 extends parallel to top portion 2b2. Side portion 2b3 is formed in a planar shape from root portion 2b1 to top portion 2b2. Even with the horn 1 according to the modification, the same effect as the embodiment can be obtained.

Reference Signs List 1: Horn 1b: Fixed portion 2: Vibration transmitting portion 2a: Base portion 2a1: Columnar portion 2a11: Tapered surface 2a2: End surface portion 2b: Spike portion 2b1: Root portion 2b2: Top portion 2b3: Side portion 3: Connecting portion 4: Vibrator 5: Oscillator 6: Cable 7: Pressure mechanism 8: Placement table 9: Holding part 10: Structure 11: First member 11A: Thin part 11B: Thick part 11C: Concave part 11a: Body part 11b: Fixing part 11b1 : Recessed portion 11b2 : Inner surface 11b3 : Bottom surface 12 : Second member 100 : Ultrasonic welding device D : Compression amount Sr : Inclined surface T1 : Thickness T2 : Thickness h : Height width r : Diameter t1 : Thickness t2 : Thickness α : Inclination Angle θ : Angle

Claims (4)

A method for manufacturing a structure, comprising an ultrasonic welding process,
The structure comprises first and second members,
The first member is a member made of solid resin,
The second member is a member made of foamed resin,
In the ultrasonic welding step, the horn is pressed against the first member arranged so as to contact the second member, and the first and second members are ultrasonically welded;
The horn has a spike and a base,
The method, wherein the spike portion is formed so as to taper in a direction in which the horn is pressed against the first member, and is provided on the tip side of the base portion. 2. The method of claim 1, wherein
The first member has a thin portion and a thick portion,
the thin portion is connected to the thick portion and is thinner than the thick portion;
The method, wherein the ultrasonic welding step presses the horn against the thinned portion. 3. The method of claim 2, wherein
The first member has a recess,
The recess has a bottom surface and an inner surface,
The bottom surface is formed in the thin portion,
The inner surface is formed to stand on the bottom surface, and the inner surface is formed with an inclined surface,
The method, wherein the inclined surface is inclined from the thick portion side to the bottom surface side. The method according to any one of claims 1 to 3,
The horn has at least three or more spikes,
The method according to claim 1, wherein the spikes are arranged to be concentrically arranged.