JP2019196822A - Caulking fastening mechanism - Google Patents

Abstract

To provide a caulking fastening mechanism capable of firmly fastening without causing looseness.SOLUTION: In a caulking fastening mechanism in which a mounted member 2 is fastened to a base member 1 by fitting the mounted member 2 into a caulking pin 11 having a cavity part 12 comprising thermoplastic synthetic resin and formed by projecting from the base member 1, and fusing and solidifying a free end 13 of the caulking pin 11 so as to form a fall-off preventing part 14, there is provided a chamfer part 22 on a base member non-contact surface 24 of the mounted member 2. The caulking pin 11 of the base member 1 is fused and solidified at an angle almost the same as an angle of the chamfer part 22 of the mounted member 2 so as to form the fall-off preventing part 14 comprising an inclined part 15 and a cross direction part 16, and to fasten the base member 1 and the mounted member 2.SELECTED DRAWING: Figure 2

Description

The present invention relates to a caulking fastening mechanism that can be fastened without causing rattling or the like.

For example, regarding assembling two workpieces made of thermoplastic synthetic resin, after a caulking pin protruding and extending vertically from the first workpiece is inserted through the hole of the second workpiece, The first and second workpieces are fixed by melting and solidifying the free end of the caulking pin protruding from the hole of the workpiece with ultrasonic vibration or the like to form a head for retaining. Has been performed more widely than before (see, for example, Patent Document 1).

Further, as shown in FIG. 4, a caulking pin 110 having a cavity 120 that protrudes and extends perpendicularly from the molding substrate 10 is formed on the molding substrate 10 made of a thermoplastic synthetic resin. After fitting through the fitting part 210, the free end 130 of the caulking pin 110 is melted and solidified by an ultrasonic horn (not shown) to form the retaining head 140, thereby fixing the attached member 20 to the molded substrate 10. Regarding the fastening mechanism, a connecting convex portion 230 is formed around the caulking pin fitting portion 210 of the attached member 20, and the caulking of the synthetic resin product that is caulked and fastened in a state where the connecting convex portion 230 is embedded in the retaining head 140. A type fastening mechanism has been proposed (see Patent Document 2).

However, in Patent Document 1, if the caulking is to be tightened firmly, not only the caulking pin but also the second workpiece is melted, resulting in poor appearance. On the other hand, if the caulking is performed weakly, the fastening portion is rattled and fastening is insufficient.

  In Patent Document 2, in order to form the caulking pin 110 having the cavity 120 into the retaining head 140 and to wrap the connecting convex portion 230 well, the shape and power of the ultrasonic horn during the caulking process are turned on. It is difficult to adjust conditions related to fastening force such as the / OFF interval.

JP-A-2-130130 JP 9-314673 A

  The present invention solves the conventional problems as described above, and provides a caulking fastening mechanism that can secure a strong fastening force without impairing the appearance and further improve workability.

In order to solve the above-mentioned problems, the present invention of claim 1 is a caulking fastening mechanism for fixing a member to be attached to the base member by using a caulking pin made of a thermoplastic synthetic resin that protrudes from the base member. The attached member includes a base member abutting surface that abuts the base member, a base member non-abutting surface opposite to the base member abutting surface, a caulking pin fitting portion through which the caulking pin passes, and a base member non-contacting portion. The caulking pin provided on the entire circumference or part of the caulking pin fitting portion of the contact surface, and the caulking pin formed on the base member penetrates the caulking pin or is provided on the fitting portion side of the attached member of the caulking pin. And the caulking pin is inserted into the caulking pin fitting portion of the mounted member, contacts the chamfered portion of the mounted member, and the tip side protrudes from the non-contacting surface of the base member of the mounted member And a lateral portion extending while abutting along the base member non-abutting surface of the attached member, and forming a retaining portion comprising the inclined portion and the lateral portion. This is a caulking fastening mechanism.

  According to the first aspect of the present invention, a chamfering pin is provided on the side surface side of the attached member, and the caulking pin protruding from the base member is inserted into the caulking pin fitting portion of the attached member, and the caulking pin is melted and solidified to be deformed. Since the inclined portion is in contact with the chamfered portion and the tip side protrudes from the non-contacting surface of the base member of the mounted member, the chamfered portion of the mounted member is blocked by the inclined portion, and the chamfered portion and the inclined portion are inclined. Since the portions are both inclined, there is no lateral displacement, and the base member and the mounted member can be firmly fastened without causing backlash or the like.

  In addition, since it has a lateral portion that is connected to the inclined portion and extends along the non-contact surface of the base member of the attached member, the inclined portion of the caulking pin presses the chamfered portion of the attached member. At the same time, the lateral portion presses the attached member from the vertical direction, and the fastening force between the base member and the attached member can be further increased.

  Further, since the caulking pin includes a cavity portion that penetrates the caulking pin or is provided on the fitting portion side of the attached member of the caulking pin, the inclined portion and the lateral portion can be easily formed.

The present invention of claim 2 is a caulking fastening mechanism in which the angle of the chamfered portion and the angle of the inclined portion of the attached member are substantially the same. In the present invention of claim 2, since the angle of the chamfered portion of the attached member and the angle of the inclined portion of the caulking pin are substantially the same, the caulking pin of the base member is melted and solidified at substantially the same angle as the angle of the chamfered portion of the attached member. Since the inclined portion is formed and the retaining portion is formed, the melted caulking pin uniformly presses the chamfered portion of the mounted member at substantially the same angle as the chamfered portion of the mounted member. Thus, the base member and the mounted member can be firmly fastened without causing rattling or the like.

  In addition, the angle at which the caulking pin of the horn that melts the caulking pin is pushed and expanded may be the same as the angle of the chamfered portion on the outer side of the attached member. Workability is improved.

  The present invention of claim 3 is a caulking fastening mechanism in which the retaining portion is formed in a circular shape when viewed from above. In the present invention of claim 3, since the retaining portion is formed in a circular shape when viewed from above, the caulking pin is spread with a uniform thickness, and as a result, the retaining portion is made of the attached member. The chamfered portion and the surface of the attached member are pressed (pressed) with an equal force, and the base member and the attached member can be firmly fastened without causing rattling or the like.

  In the present invention, a base member having a caulking pin having a hollow portion is fitted into a mounting member having a chamfered caulking pin fitting portion, and the caulking pin of the base member is melted and solidified to be inclined at substantially the same angle as the chamfering angle of the mounting member. Since the part is formed to form a retaining part, the inclined part presses the chamfered part of the attached member at the same angle as the angle of the chamfered part of the attached member, and the base member and the attached part are free from rattling. The member can be firmly fastened. Further, workability including setting of the horn design and the temperature and pressure for melting the horn is improved.

(A) is a top view of the crimping fastening mechanism of embodiment of this invention, (b) is AA sectional drawing of (a). It is sectional drawing of the crimping | fastening fastening mechanism of this invention, and is a figure which shows the relationship between the crimping pin 11 and the retaining part 14. FIG. The process of forming the crimping mechanism of this invention is shown, (a) is the state before fitting the to-be-attached member 2 in the base member 1, (b) has fitted the to-be-attached member 2 in the base member 1. FIG. The state, (c) is during the melting of the caulking pin 11, and (d) is a sectional view after the caulking pin 11 is melted and solidified (after the retaining portion 14 is formed). It is sectional drawing of the conventional crimping fastening mechanism.

  FIG. 1A is a top view of a caulking fastening mechanism according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA in FIG. FIG. 2 is a diagram showing the relationship between the caulking pin 11 and the retaining portion 14. In the figure, reference numeral 1 denotes a base member, and reference numeral 2 denotes a member to be attached that is caulked to the base member 1.

A caulking pin 11 having a cavity 12 protrudes from the base member 1 substantially vertically. The caulking pin 11 is fitted into the caulking pin fitting portion 21 of the attached member 2, and the base member 1 and the attached member 2 come into contact with the base member 1. The surface 23 is brought into contact. Then, the free end 13 of the caulking pin 11 protruding from the base member non-contact surface 24 of the mounted member 2 is melted and solidified to form a retaining portion 14 including an inclined portion 15 and a lateral portion 16. The member 2 is fixed to the base member 1.

A chamfered portion 22 is formed on the base member non-contact surface 24 of the caulking pin fitting portion 21 of the mounted member 2, and an inclined portion 15 formed by melting and solidifying the free end 13 of the caulking pin 11 by a caulking horn 3 described later. It is provided in the abutting part.

As a result, the hollow end 12 of the free end 13 of the caulking pin 11 of the base member 1 is expanded at substantially the same angle as the chamfered portion 22 of the attached member 2, and finally, the caulking pin 11 of the base member 1 is The inclined portion 15 is formed at substantially the same angle as the chamfered portion 22 of the mounting member 2, and closes the caulking pin fitting portion 21 of the mounted member 2.

  Therefore, even when there is a lateral gap between the caulking pin fitting portion 21 of the attached member 2 and the caulking pin 11 of the base member 1, there is no backlash or lateral displacement between the base member 1 and the attached member 2. A strong fastening force that does not occur can be secured.

Further, the free end 13 of the caulking pin 11 closes the caulking pin fitting portion 21 of the mounted member 2 with the inclined portion 15 having substantially the same angle as the chamfered portion 22 of the mounted member 2, and the mounted member from the tip of the inclined portion 15. The horizontal portion 16 having a constant thickness is formed in the horizontal direction 2 to complete the retaining portion 14.

Therefore, the melted and solidified inclined portion 15 presses the chamfered portion 22 of the mounted member 2 at the same angle as the chamfered portion 22 of the mounted member 2 and the lateral portion 16 presses the mounted member 2 from the vertical direction. The retaining portion 14 is formed, and the fastening force between the base member 1 and the attached member 2 can be further increased.

  Further, as shown in FIG. 1 (a), the retaining portion 14 is formed in a circular shape when the caulking fastening mechanism of the present invention is viewed from above, so that the hollow portion 12 of the caulking pin 11 is uniformly expanded. As a result, the retaining portion 14 is pressed (pressed) with a uniform force against the chamfered portion 22 of the mounted member 2 or the surface of the mounted member, and the base member 1 is free from rattling or the like. And the mounted member 2 can be firmly fastened.

  Next, a specific caulking fastening process of the present embodiment will be described based on FIGS. FIG. 3A shows a state before the base member 1 is fitted into the attached member 2, FIG. 3B shows a state where the caulking pin 11 of the base member 1 is fitted into the caulking pin fitting portion 21 of the attached member 2, and FIG. (D) is the figure which completed the melt-solidification of the crimping pin 11 of the base member 1, and completed the retaining part 15 during melting of the crimping pin 11. FIG. Each figure is a sectional view.

(Base member 1)
The base member 1 and the caulking pin 11 are integrally molded products using PE (polyethylene) which is a thermoplastic synthetic resin, and the caulking pin 11 has an outer diameter of 8.0 mm. The diameter of the cavity 12 of the caulking pin 11 is 3 mm and the thickness is 2.5 mm. The base member 1 and the caulking pin 11 may be made of different materials.

(Mounted member 2)
The mounted member 2 is POM (polyacetal) which is a thermoplastic synthetic resin, and its thickness is 2 mm. The diameter of the caulking pin fitting portion 21 is 9.2 mm, and the angle α of the chamfer 22 formed on the base member non-contact surface 24 of the mounted member 2 is 45 °. The angle α of the chamfer 22 is shown in FIG. The angle α of the chamfer 22 formed on the base member non-contact surface 24 of the mounted member 2 is preferably 30 ° to 60 °.

When the angle α is small, the angle from the substantially vertical portion of the caulking pin 11 existing in the caulking pin fitting portion 21 of the attached member 2 to the inclined portion 15 is steep, and the strength of the retaining portion 14 may be reduced. . Moreover, when the angle α is large, the inclined portion 15 becomes gentle, and the force by which the inclined portion 15 presses the chamfered portion 22 of the attached member 2 may be weakened.

Here, when the caulking pin 11 of the base member 1 is fitted in the difference between the outer diameters of the caulking pin fitting portion 21 and the caulking pin 11 of the attached member 2, that is, the caulking pin fitting portion 21 of the attached member 2. This is because the product variation and assembly variation are absorbed.

(Caulking horn 3)
In the present embodiment, the caulking pin 11 is melted by heat using high frequency. The caulking horn 3 is made of aluminum and includes a fixing portion 31 and a caulking shape forming portion 32. The fixing part 31 is a part for fixing the caulking horn 3 to a caulking device for generating a high frequency (not shown) and melting the free end 13 of the caulking pin 11 of the base member 1. Further, the caulking shape forming part 32 melts and spreads the free end 13 of the caulking pin 11 to form the retaining part 14. The material of the caulking horn 3 is not limited to aluminum, and may be other metals (including alloys).

The caulking shape forming portion 32 of the caulking horn 3 is a hollow insertion portion 33 that combines a cylindrical shape and a conical shape to be inserted into the cavity 12 of the free end 13 of the caulking pin 11, and a frustoconical shape that expands the free end 13 of the caulking pin 11. The expansion part 34 and the pressing pin 35 that presses the free end 13 of the caulking pin 11 in a direction parallel to the surface of the attached member 2. The push-out portion 34 forms the inclined portion 15 in the retaining portion 14, and the pressing portion 35 forms the lateral portion 16 in the retaining portion 14. The diameter of the cavity insertion portion 33 is 3 mm, and the angle β of the expansion portion 34 is 45 °. The angle β of the expanded portion 34 is shown in FIG. In addition, when the angle α of the chamfer 22 of the attached member 2 is changed, the angle β of the push-expanded portion 34 is changed according to the angle α.

Formed on the outer side of the pressing portion 35 is a formation end judging portion 36 that is a surface parallel to the attached member 2 protruding to the base member non-contact surface 24 side of the attached member 2. The level difference between the pressing portion 35 and the formation end determining portion 36 is set to be equal to the thickness of the pressing portion 35 and the base member non-contact surface 24 of the attached member 2, that is, the lateral portion 16 of the retaining portion 14. . This is to ensure that the caulking is completed.

(Caulking process)
As shown in FIGS. 3A and 3B, the caulking pin 11 of the base member 1 is fitted into the caulking pin fitting portion 21 of the mounted member 2, and the base member contact surface 23 of the base member 1 and the mounted member 2 is brought into contact with each other. After the contact, it is set in a crimping device (not shown). At this time, there is a gap of 1.2 mm in the lateral direction between the caulking pin fitting portion 21 and the caulking pin 11, although it is a little. This is due to the tolerance of both members on the assumption that the caulking pin 11 can be securely fitted into the caulking pin fitting portion 21.

Next, the fixing portion 31 of the caulking horn 3 is fixed to a caulking device (not shown), and after the caulking horn 3 is heated to 150 ° C., the cavity insertion portion 33 of the caulking horn 3 is fitted into the attached member 2. When the caulking horn 3 is lowered into the cavity 12 of the caulking pin 11 of the base member 1, and the caulking horn 3 is further lowered, the free end 13 of the caulking pin 11 protruding from the attached member 2 is caused by the expansion portion 34 of the caulking horn 3. It is expanded while being melted to form the inclined portion 15 (FIG. 3C). At this time, the free end 13 of the melted caulking pin 11 is expanded at an angle of 45 ° of the expanded portion 34.

When the caulking horn 3 is further lowered, the free end 13 of the melted caulking pin 11 reaches the end of the spreading portion 34 of the caulking horn 3, and then the free end 13 of the caulking pin 11 is moved to the caulking horn 3. The direction is changed by the pressing portion 35 to form the lateral portion 16.

And the formation completion judgment part 36 of the caulking horn 3 is in contact with the base member non-contact surface 24 of the mounted member 2 and, at the same time, the inclined portion 15 that has been spread out completely blocks the chamfered portion 22 of the mounted member 2. At the same time, the lateral portion 16 also contacts the base member non-contact surface 24 of the mounted member 2, and the formation of the retaining portion 14 by the inclined portion 15 and the lateral portion 16 is completed. The determination of the end of formation of the retaining portion 14 is made by detecting the lowermost portion of the formation end determination portion 36 with a camera to which a caulking device (not shown) is attached. The determination of the end of formation of the retaining portion 14 may be made by detecting the distance between the formation end determination portion 36 and the base member non-contact surface 24 of the attached member 2.

Finally, the caulking horn 3 is raised, the retaining portion 14 is cooled, and the retaining portion 14 is formed as shown in FIG. At this time, since the angle of the chamfer 22 of the attached member 2 and the angle of the caulking pin 11 of the base member 1 are the same, the lateral direction between the caulking pin fitting portion 21 of the attached member 2 and the caulking pin 11 of the base member 1 is the same. Even if there is a gap, it is possible to secure a strong fastening force that does not cause backlash or lateral displacement between the base member 1 and the mounted member 2.

Moreover, since the horizontal direction part 16 forms the retaining part 14 in the form which presses down the to-be-attached member 2 from the orthogonal | vertical direction, the fastening force between the base member 1 and the to-be-attached member 2 can further be increased.

The implementation of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the object of the present invention.

For example, in the present embodiment, the caulking pin 11 is melted by heat using high frequency, but may be melted using ultrasonic waves.

  For example, in the present embodiment, the end of molding is detected by detecting the position of the formation end determination unit 36 of the caulking horn 3 with a sensor installed in the caulking device, but the descent time of the caulking horn 3 in the caulking device or the caulking You may detect by the stroke length of the fall of the horn 3. FIG.

  For example, in the present embodiment, the base member 1 and the attached member 2 are made of different materials, but may be the same member.

  For example, in the present embodiment, both the base member 1 and the attached member 2 are thermoplastic resins. However, a chamfered portion 22 is provided on the base member non-contact surface 24 of the attached member 2, and the caulking pin 21 is a thermoplastic resin. Can be used to join different materials different from the thermoplastic resin.

  For example, in this embodiment, the chamfered portion 22 of the attached member 2 is formed in a straight line, but may be drawn in an arc. In this case, it is desirable that the caulking pin 11 is expanded by the caulking horn 3 so as to maintain the original thickness.

  For example, the caulking shape forming portion 32 of the caulking horn 3 includes a cavity insertion portion 33 that combines a cylindrical shape and a conical shape to be inserted into the cavity 12 of the free end 13 of the caulking pin 11, and a truncated cone that expands the free end 13 of the caulking pin 11. Although it was composed of the shape expansion part 34 and the pressing part 35 that presses the free end 13 of the caulking pin 11 in a direction parallel to the surface of the mounted member 2, the cavity insertion part 33 that combines the cylindrical shape and the conical shape is omitted, You may comprise the conical expansion part 34 and the press part 35 which presses the free end 13 of the crimping pin 11 in the direction parallel to the surface of the to-be-attached member 2. FIG.

1 Base member 2 Mounted member 3 Caulking horn 11 Caulking pin 12 Cavity 13 Free end 14 Removable portion 15 Inclination portion 16 Lateral portion 21 Caulking pin fitting portion 22 Chamfering portion 23 Base member abutting surface 24 Base member non-abutting surface 31 Fixing portion 32 Caulking shape forming portion 33 Cavity insertion portion 34 Expanding portion 35 Pressing portion 36 Formation end determining portion

Claims (3)

A caulking fastening mechanism for fixing a member to be attached to the base member using a caulking pin made of a thermoplastic synthetic resin formed to protrude from the base member,
The attached member includes a base member contact surface that comes into contact with the base member;
A base member non-contact surface opposite to the base member contact surface;
The caulking pin fitting portion through which the caulking pin penetrates;
A chamfered portion provided on the entire circumference or part of the caulking pin fitting portion of the base member non-contact surface;
The caulking pin formed on the base member includes a hollow portion that penetrates the caulking pin or is provided on the fitting portion side of the attached member of the caulking pin,
The caulking pin is inserted into the caulking pin fitting portion of the attached member,
The base member of the mounted member is in contact with the chamfered portion of the mounted member, and the leading end side of the mounted member protrudes from the base member non-contacting surface of the mounted member, and is connected to the inclined portion. Having a lateral portion extending while abutting along a non-abutment surface;
A caulking fastening mechanism, wherein a retaining portion comprising the inclined portion and the lateral portion is formed.   The caulking fastening mechanism according to claim 1, wherein an angle of the chamfered portion and an angle of the inclined portion of the attached member are substantially the same.   The caulking fastening mechanism according to claim 1, wherein the retaining portion is formed in a circular shape when viewed from above.

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