JP2010071313A - Caulking screw and caulking screw jointing structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide large rotation preventive force and slipping-out preventive force for a caulking nut 1, by joining the caulking nut 1 to a plate-like workpiece by relatively small press force. <P>SOLUTION: The caulking nut 1 includes a caulking cylinder 4 turning around a screw hole 3 on the seat surface side of a nut body 2, and includes an annular groove 5 turning around the caulking cylinder 4, and forms a plurality of recessed parts 9 at an interval in the peripheral direction on an annular groove outer peripheral surface, and also includes a gusset-shaped rib 11 over a bottom surface from an inner peripheral surface of the annular groove 5. A rising wall of a burring hole of a workpiece is pressed in the annular groove 5, and is brought into close contact with the recessed parts 9, and becomes a state of hugging the gusset-shaped rib 11, and the caulking cylinder 4 is caulked to the burring hole peripheral edge on the opposite side of the rising wall of the workpiece. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

    The present invention relates to a caulking screw and a caulking screw joining structure.

    Projection welding is widely used for joining bolts and nuts to plate-like workpieces such as automobile body panels. However, in the case of this projection welding, a large-capacity power receiving facility, electrical wiring, cooling tower, and water supply / drainage facility are required. In addition, consumables such as welding electrodes are required, and it is also necessary to secure skilled personnel and time for the replacement.

    On the other hand, it is also known to join bolts and nuts to the base plate by pressing. The nut body is driven from above the plate-like workpiece set on the lower mold, and the workpiece is punched and caulked simultaneously to attach the nut body to the metal plate.

    For example, Patent Document 1 describes that a caulking nut is formed with an annular groove around a screw hole in a seating surface of a nut body. On the outer peripheral surface of the annular groove of the nut body, a plurality of recesses having a circular cross section perpendicular to the nut axial direction are formed at intervals in the circumferential direction. On the inner circumferential surface of the annular groove, arc-shaped convex portions that protrude toward the respective arc-shaped concave portions on the outer circumferential surface of the annular groove are formed. On the bottom surface of the annular groove, a convex portion that requires rotation prevention is formed. The workpiece is plastically deformed and press-fitted into the annular groove of the nut main body, and the arc-shaped concave portion and the arc-shaped convex portion prevent the nut main body from idling. The outer peripheral surface of the annular groove is tapered so that the diameter decreases toward the opening of the groove, and the nut body is prevented from coming off by this taper.

Patent Document 2 describes that a caulking nut is provided with an anti-rotation serration on the outer circumferential surface of the annular groove, and that the inner cylindrical portion inside the annular groove has a taper shape with a hem extending. . The taper-shaped inner cylinder portion prevents the nut from coming off.
JP 60-252814 A Japanese Patent Laid-Open No. 11-193808

    However, in the case of the caulking nut of Patent Document 1, when a rotational torque exceeding 30 N · m is applied, the nut rotates idly. One reason for this is considered to be that the outer circumferential surface and the inner circumferential surface of the annular groove are similarly formed in a circular arc shape. That is, the groove width of the annular groove is substantially the same between the portion where the recess / projection is provided and the portion where the recess / projection is not provided, and is substantially constant over the entire circumference. . For this reason, when a large rotational torque is applied to the nut, plastic deformation of the press-fitting portion of the work press-fitted into the annular groove is likely to occur, and the nut moves with respect to the work. Once the nut is deviated in rotation, even if the part can be stopped on the work, the part will rattle due to vibrations or the like on the work and generate noise. Moreover, a large retaining force cannot be obtained only by the taper of the outer circumferential surface of the annular groove.

    On the other hand, in the case of the caulking nut of the above-mentioned Patent Document 2, it is not possible to expect a large anti-rotation force by serration, and a relatively large retaining force can be obtained with a tapered inner cylinder portion. When the portion is tapered, the screw hole is likely to be deformed.

    In addition, since both the caulking nuts of Patent Documents 1 and 2 perform punching and caulking of the workpiece at the same time when joining to the workpiece, a large pressing force is required, and the punching is performed by the nut. In order to do so, it is necessary to use a hard material for the nut, which increases the cost.

    Therefore, an object of the present invention is to enable a caulking screw (nut or bolt) to be joined to a workpiece with a relatively small pressing force, and to obtain a large detent force and retaining force. .

    In order to solve such problems, the present invention forms a burring hole in the workpiece in advance, forms a caulking cylinder portion in the caulking screw, and gives a special anti-rotation shape to the annular groove. I tried to do it.

The invention according to claim 1 is a caulking nut to be joined to a work having a burring hole in which a cylindrical rising wall is formed at the periphery,
A nut body having a screw hole;
A caulking tube that is provided on the seat surface side of the nut body so as to go around the screw hole and is inserted into the burring hole of the workpiece from the rising wall side and caulked to the peripheral edge of the burring hole on the side opposite to the rising wall. And
On the seat surface side of the nut body, an annular groove into which the rising wall of the workpiece is press-fitted is formed so as to go around the caulking cylinder,
On the outer circumferential surface of the annular groove, a plurality of recesses are formed at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The rising wall of the workpiece is press-fitted into an annular groove of the nut body, and is held by each gusset-shaped rib and pressed into each recess of the outer circumferential surface of the annular groove.

    According to the present invention, since the burring hole is formed in advance in the workpiece, it is not necessary to punch the workpiece with the caulking nut when joining the caulking nut to the workpiece. For this reason, the pressing force required for the joining is reduced, and it is not necessary to limit the material of the caulking nut to a hard material. When the rising wall of the workpiece is press-fitted into the annular groove of the caulking nut, the rising wall is held by each gusseted rib formed from the inner peripheral surface to the bottom surface of the annular groove, and the inclined top surface of the gusseted rib The tip is spread to the outside and is pressed against each concave portion of the outer circumferential surface of the annular groove. A large anti-rotation force is obtained for the caulking nut by holding the rising wall against each gusset-shaped rib and pressing it against each recess.

    The important point is not to provide separate rotation-preventing ribs on the inner circumferential surface and bottom surface of the annular groove, but to provide gusseted (ie triangular) ribs that are continuous from the inner circumferential surface to the bottom surface of the annular groove. It is in. For this reason, the rising wall is guided by the gusset-shaped rib and strongly pressed against the concave portion of the inner peripheral surface of the annular groove, and further, the rising wall and the gusset-shaped rib at the corner formed by the inner peripheral surface and the bottom surface of the annular groove. The hug is strong and the detent force is increased. Further, since the gusset-shaped rib has a portion raised from the bottom surface of the annular groove in the concave portion of the outer peripheral surface of the annular groove, the anti-rotation effect by the concave portion of the outer peripheral surface of the annular groove and the anti-rotation effect by the rib portion raised from the bottom surface in the concave portion Together with this, a large detent force can be obtained.

    Moreover, the caulking cylinder of the caulking nut is caulked to the peripheral edge of the burring hole on the side opposite to the rising wall of the workpiece, thereby obtaining a large retaining force for the caulking nut.

    A space between adjacent concave portions on the outer peripheral surface of the annular groove can be formed in an arc shape or can be formed flat. Forming flat means that the outer peripheral surface of the annular groove is polygonal and a recess is provided at each corner, thereby forming a flat surface between the recesses. Or you may make it a recessed part and a convex part line up by turns on the annular groove outer peripheral surface. The concave portion can have a transverse cross-sectional shape (cross-sectional shape perpendicular to the nut axis direction) formed in an arc shape, a triangular mountain shape, or a rectangular shape (including a trapezoidal shape). The opening width of the recess is preferably about 1/30 or more and 1/6 or less of the outer circumferential length of the annular groove.

    Regarding the shape of the outer circumferential surface of the annular groove and the recess, the other inventions described below are also the same.

The invention according to claim 2 is a joining structure of a caulking nut joined to a work having a burring hole in which a cylindrical rising wall is formed at the periphery,
The caulking nut includes a nut body having a screw hole, and a caulking portion that surrounds the screw hole provided on the seating surface side of the nut body,
On the seat surface side of the nut body, an annular groove is formed around the crimped portion.
A plurality of recesses are formed on the outer circumferential surface of the annular groove at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The rising wall of the workpiece is press-fitted into the annular groove of the caulking nut, is held by each gusset-like rib, and is pressed against each concave portion of the outer circumferential surface of the annular groove,
The caulking portion of the caulking nut is caulked on the peripheral edge of the burring hole opposite to the rising wall of the work.

    Therefore, as described above, a large anti-rotation force is obtained in the caulking nut by the concave portion on the outer peripheral surface of the annular groove and the gusset-shaped rib extending from the inner peripheral surface to the bottom surface of the annular groove, and the caulking portion causes a large slip to the caulking nut. A stopping force is obtained.

The invention according to claim 3 is a caulking bolt to be joined to a workpiece having a burring hole in which a cylindrical rising wall is formed at the periphery,
A threaded portion;
A head portion provided at a proximal end of the screw portion;
For caulking, which is provided on the seat surface side of the head so as to go around the threaded portion and is inserted into the burring hole of the workpiece from the rising wall side and caulked to the peripheral edge of the burring hole opposite to the rising wall. With a cylinder,
On the seat surface side of the head, an annular groove into which the rising wall of the work is press-fitted is formed so as to go around the caulking cylinder,
A plurality of recesses are formed on the outer circumferential surface of the annular groove at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The rising wall of the workpiece is press-fitted into the annular groove of the head, is held by each gusset-shaped rib, and is pressed into each concave portion of the outer circumferential surface of the annular groove.

The invention according to claim 4 is a joining structure of caulking bolts joined to a workpiece having a burring hole in which a cylindrical rising wall is formed at the periphery,
The caulking bolt includes a screw portion, a head portion provided at the base end of the screw portion, and a caulking portion that surrounds the periphery of the screw portion provided on the seat surface side of the head portion,
On the seating surface side of the head, an annular groove is formed around the caulking portion.
On the outer circumferential surface of the annular groove, a plurality of recesses are formed at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The rising wall of the workpiece is press-fitted into the annular groove of the caulking bolt, is held by each gusset-shaped rib, and is pressed against each concave portion of the outer circumferential surface of the annular groove,
The caulking portion of the caulking bolt is caulked to the peripheral edge of the burring hole opposite to the rising wall of the workpiece.

    In the case of the above-described caulking bolt as well, as in the above-described caulking nut, the caulking bolt has a large detent force due to the concave portion on the outer circumferential surface of the annular groove and the gusseted rib extending from the inner circumferential surface to the bottom surface of the annular groove. Therefore, a large retaining force can be obtained for the caulking bolt.

    As described above, according to the inventions relating to the caulking nut and the caulking bolt, and the inventions relating to the joining structure of the caulking nut and the caulking bolt, while providing the recess on the outer circumferential surface of the annular groove, Since a gusseted rib extending from the inner peripheral surface of the annular groove to the bottom surface is provided, and the rising wall of the workpiece is held by the gusseted rib extending from the inner peripheral surface of the annular groove to the bottom surface and pressed against the concave portion of the outer peripheral surface of the annular groove. A large detent force is obtained for each nut and bolt, and the caulked portion on the nut and bolt side is caulked to the periphery of the burring hole of the workpiece, so that a large retaining force is obtained for each nut and bolt. Moreover, since the burring holes are formed in advance in the work, the caulking nut and the caulking bolt are attached to the work with a relatively small pressing force. It can be reliably joined.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

<Embodiment 1>
−Crimping nut configuration−
In the iron caulking nut 1 shown in FIG. 1, reference numeral 2 denotes a nut body having a screw hole 3. On the seat surface side of the nut body 2, there is provided a caulking cylinder 4 which is formed in a cylindrical shape around the screw hole 3 and protrudes in the nut axial direction, and goes around the caulking cylinder 4. An annular groove 5 is formed.

    As shown in FIG. 2, the outer circumferential surface 6 of the annular groove 5 is formed in a hexagonal shape (a hexagonal shape as an example of a polygon. The same applies hereinafter). A concave portion 7 having a circular arc shape is formed. The outer circumferential surface 6 of the annular groove including the recess 7 is tapered such that the width of the annular groove becomes narrower as it approaches the bottom surface 9 of the annular groove 5.

    On the other hand, the inner peripheral surface 8 of the annular groove 5 is formed in a concentric hexagon corresponding to the hexagon of the annular groove outer peripheral surface 5. The portion extending from the inner peripheral surface 8 to the bottom surface 9 of the annular groove 5 has a continuous portion that protrudes from the inner peripheral surface 8 toward the recess 7 and a portion that protrudes from the bottom surface 9 at the portion of the recess 7. Gusset-like ribs 11 are formed corresponding to the respective recesses 7 of the outer peripheral surface 5. The top surface of the gusset-shaped rib 11 is inclined so that the amount of protrusion from the inner circumferential surface 8 of the annular groove gradually increases as it approaches the bottom surface 9 of the annular groove, and continues smoothly to the raised portion of the bottom surface 9 of the annular groove.

    As shown in FIG. 3, the upper end of each hexagonal apex of the annular groove inner peripheral surface 8 is formed in an inclined shoulder portion 13. Further, the top surface 14 of the caulking cylinder 4 is formed in a tapered surface that becomes lower toward the inner peripheral edge.

−Method of joining caulking nut to workpiece−
FIG. 4 shows how the caulking nut 1 is joined to an iron plate-like workpiece 15 by pressing. A burring process is performed on the work 15 in advance, and a burring hole 17 having a cylindrical rising wall 16 is formed at the periphery. The burring hole 17 is formed in such a size that the caulking cylinder 4 of the caulking nut 1 can be fitted. The inner peripheral surface of the rising wall 16 rises with a rounded surface 16a having an R (radius) 3 to 5 times the plate thickness, and the top inner peripheral surface of the rising wall 16 also warps outward with a rounded surface 16b. In FIG. 4, 18 is a work cradle, and 19 is a caulking die provided on the work cradle 18 so as to be movable up and down.

    The caulking die 19 includes a columnar base portion 19a inserted into the lifting hole 20 of the work cradle 18 and a columnar guide 19b protruding upward from the center of the upper surface of the base portion 19a, and a base portion 19a continuing from the lower end of the guide 19b. Is formed on the inclined surface 19c for caulking that gradually becomes lower toward the periphery. A spring 22 is provided between the base 19 a and the base 24, and the caulking die 19 is urged by the spring 22 so as to protrude upward from the work receiving base 18. The guide 19b is formed so as to fit into the screw hole 3 from the caulking cylinder 4 of the caulking nut 1, and the top is formed in a hemispherical shape.

    Hereinafter, the joining method will be described. The work 15 is placed on the work cradle 18 so that the rising wall 16 faces upward so that the burring hole 17 is concentric with the caulking die 19. Next, as shown in FIG. 5, the caulking nut 1 is placed on the work 15, the caulking cylinder 4 is fitted into the burring hole 17, supported by the caulking inclined surface 19 c of the caulking die 19, and the caulking nut 1 is pressurized. Press down with ram 23.

    As the pressurizing ram 23 is lowered, the caulking nut 1 is lowered, and the rising wall 16 of the work 15 is guided by the shoulder portion 13 of the caulking nut 1 and deformed to the outside. The spring 22 is compressed until the lower end of the caulking inclined surface 19c of the caulking die 19 reaches the same height as the upper surface of the work cradle 18. At this time, the caulking die 19 contacts the base 24.

    As the pressurization ram 23 is further lowered, the rising wall 16 of the work 15 is press-fitted into the annular groove 5 of the caulking nut 1 while being plastically deformed. At this time, the portion of the rising wall 16 corresponding to the gusset-shaped rib 11 is guided by the rib 11 and spreads outward, and is pressed against each arcuate recess 7 of the outer circumferential surface 6 of the annular groove. On the other hand, the caulking cylinder 4 of the caulking nut 1 is guided by the caulking inclined surface 19c and the front end portion expands outward, enters the gap between the upper surface of the work receiving base 18 and the work 15, and the work 15 It is caulked to the peripheral edge of the burring hole on the side opposite to the rising wall 16.

    6 to 8 show a state in which the caulking nut 1 is joined to the work 15. That is, the rising wall 16 of the workpiece 15 is plastically deformed, and the plastically deformed portion 16 a enters each arcuate recess 7 of the annular groove outer peripheral surface 6 of the caulking nut 1, and is hugged to each gusset-like rib 11 of the annular groove 5. Yes. FIG. 7 shows a state in which the plastic deformation portion 16 a fills each arc-shaped recess 7 and is in close contact with the outer circumferential surface 6 of the annular groove, and projects toward the recess 7 from the inner circumferential surface 8 of the annular groove of each gusset-shaped rib 11. It shows the state of hugging the part. FIG. 8 shows a state in which the plastic deformation portion 16 a is hung on a portion of each gusset-like rib 11 protruding from the bottom surface 9 of the annular groove. The caulking cylinder 4 of the caulking nut 1 is plastically deformed so that the tip extends outward, and is caulked to the peripheral surface of the burring hole on the opposite side of the rising wall 16 of the workpiece 15 to form a caulking portion 4a.

    Accordingly, with such a caulking nut 1 joining structure, even if a large rotational torque acts on the caulking nut 1, the rising wall plastic deformation portion 16 a of the work 15 is applied to each arc-shaped concave portion 7 of the annular groove outer peripheral surface 6. Since it is pressed and hugged by each gusset-like rib 11, the rotational displacement of the caulking nut 1 is prevented. In particular, at the corner formed by the inner peripheral surface 8 and the bottom surface 9 of the annular groove 5, the plastic deformation portion 16a is strongly held to the gusset-like rib 11, and a large detent force is obtained. In addition, the anti-rotation effect by the concave portion 7 of the outer circumferential surface 6 of the annular groove and the anti-rotation effect by the portion of the gusset-shaped rib 11 protruding from the bottom surface 9 of the annular groove in the concave portion 7 combine to obtain a large anti-rotation force. It is done. Further, since the caulking cylinder 4 of the caulking nut 1 is caulked to the peripheral surface of the burring hole of the work 15, a large retaining force can be obtained for the caulking nut 1. When the caulking nut 1 having a nominal screw size M6 is joined to the workpiece 15 having a plate thickness of 1.6 mm, the caulking nut 1 does not deviate in rotation with a rotational torque of 65 N · m (650 kgf · cm), and the nut axial direction Even if a force of 7000 N was applied, the caulking nut 1 did not peel off from the work 15.

<Embodiment 2>
FIG. 9 shows an iron caulking bolt 31 according to this embodiment. The caulking bolt 31 includes a screw portion 32, a head portion 33 provided at the base end of the screw portion 32, and a caulking bolt provided around the screw portion 32 on the seating surface side of the head portion 33. And a tube 34. On the seat surface side of the head 33, an annular groove 35 that surrounds the caulking cylinder 34 is formed. On the inner peripheral edge side of the top surface of the caulking tube 34, a roundness 34a is provided as shown in FIG.

    As shown in FIG. 11, the outer circumferential surface 36 of the annular groove 35 is formed in a hexagonal shape like the caulking nut 1 of the first embodiment, and a concave portion 37 having a circular cross-sectional shape is formed at each top portion thereof. Is formed. The outer circumferential surface 36 of the annular groove including the recess 37 is tapered such that the width of the annular groove becomes narrower toward the bottom surface 39 of the annular groove 35.

    On the other hand, the inner peripheral surface 38 of the annular groove 35 is formed in a concentric hexagon corresponding to the hexagon of the annular groove outer peripheral surface 35. The portion extending from the inner peripheral surface 38 to the bottom surface 39 of the annular groove 35 has a continuous portion that protrudes from the inner peripheral surface 38 toward the concave portion 37 and a portion that protrudes from the bottom surface 39 at the portion of the concave portion 37. Gusset-like ribs 41 are formed corresponding to the respective concave portions 37 of the outer peripheral surface 35. The top surface of the gusset-shaped rib 41 is inclined so that the amount of protrusion from the inner circumferential surface 38 of the annular groove gradually increases as it approaches the bottom surface 39 of the annular groove, and continues smoothly to the raised portion of the bottom surface 39 of the annular groove. Moreover, the upper end of each hexagonal top part of the annular groove inner peripheral surface 38 is formed in an inclined shoulder part 43 as shown in FIG.

    FIG. 12 shows how the caulking bolt 51 is joined to the iron plate-like workpiece 15 by pressing. A burring process is performed on the work 15 in advance, and a burring hole 17 having a cylindrical rising wall 16 is formed at the periphery. The burring hole 17 is formed in such a size that the caulking cylinder 34 of the caulking bolt 31 can be fitted. The inner peripheral surface of the rising wall 16 rises with a rounded surface 16a having an R (radius) of 3 to 5 times the plate thickness, and the top inner peripheral surface of the rising wall 16 also warps outward with a rounded surface 16b. In FIG. 12, 45 is a caulking die, and 23 is a pressure ram. The caulking die 45 has a work receiving surface 46 on which the work 15 is placed, and a screw receiving hole 47 that receives the screw portion 32 of the caulking bolt 31. A caulking taper surface 68 is formed on the periphery of the opening of the screw receiving hole 47.

    Hereinafter, the joining method will be described. The work 15 is placed on the work receiving surface 46 of the caulking die 45 so that the center of the burring hole 17 coincides with the center of the screw receiving hole 47. The caulking bolt 31 is put on the work 15 and the screw portion 32 is put into the screw receiving hole 47 so that the shoulder portion 43 of the caulking bolt 31 is supported by the rising wall 16 of the work 15. From this state, the pressurizing ram 23 is lowered to press-fit the rising wall 16 into the annular groove 35 of the caulking bolt 31, and the applied pressure is increased in the latter half of the lowering. As a result, the rising wall 16 is press-fitted into the annular groove 35 of the caulking bolt 31 while being plastically deformed. At this time, a portion of the rising wall 16 corresponding to the gusset rib 41 is guided by the rib 41 and spreads outward, and is pressed against each arc-shaped recess 37 of the annular groove outer peripheral surface 36. On the other hand, the caulking cylinder 34 of the caulking bolt 31 has its tip end surface 34 a sliding on the work receiving surface 46 and expanding outward, and is pressed against the work receiving surface 46.

    13 to 15 show a state in which the caulking bolt 31 is joined to the work 15. That is, the rising wall 16 of the work 15 is plastically deformed, and the plastically deformed portion 16 a enters each arc-shaped recess 37 of the annular groove outer peripheral surface 36 of the caulking bolt 31 and is hung on each gusset-like rib 41 of the annular groove 35. ing. FIG. 14 shows the state in which the plastic deformation portion 16a enters each arcuate recess 37 and is in close contact with the outer circumferential surface 36 of the annular groove, as well as the annular groove inner circumferential surface 38 of each gusset-like rib 41 toward the recess 37. The state of being hugged by the protruding part is shown. FIG. 15 shows a state in which the plastic deformation portion 16 a is hung on a portion of each gusset-like rib 41 protruding from the bottom surface 39 of the annular groove. The caulking cylinder 34 of the caulking bolt 31 is plastically deformed so that the tip is spread outward, and is caulked to the peripheral surface of the burring hole opposite to the rising wall 16 of the work 15 to form an caulking portion 34a.

    Therefore, if such a caulking bolt 31 is joined, even if a large rotational torque acts on the caulking bolt 31 as in the case of the first embodiment, the concave portion 37 of the annular groove outer peripheral surface 36 and the gusset-like rib 41 Shows a strong resistance, and the rotation displacement of the caulking bolt 31 is prevented. Further, since the caulking cylinder 54 of the caulking bolt 31 is caulked to the peripheral surface of the burring hole of the work 15, a large retaining force is obtained for the caulking bolt 31.

    The first and second embodiments are cases in which an iron caulking screw (nut or bolt) is joined to an iron work, but an aluminum or aluminum alloy caulking screw is joined to an iron work, or an iron caulking screw. Can be joined to a workpiece made of aluminum or an aluminum alloy, or a caulking screw made of aluminum or an aluminum alloy can be joined to a workpiece made of aluminum or an aluminum alloy.

    Moreover, regarding the shape of the annular groove, the hexagonal shape is used in the first and second embodiments, but it may be a triangular shape, a rectangular shape, or other polygonal shapes.

It is a perspective view of a caulking nut concerning Embodiment 1 of the present invention. It is a top view of a caulking nut. It is sectional drawing in the AA line of FIG. It is sectional drawing (sectional drawing corresponding to the AA line of FIG. 2) which shows the same crimping nut, a workpiece | work, a workpiece cradle, and the type | mold for crimping. It is sectional drawing (sectional drawing corresponding to the AA line of FIG. 2) which shows the aspect which joins the same caulking nut to a workpiece | work. It is sectional drawing (sectional drawing corresponding to the AA line of FIG. 2) which shows the state in which the same crimping nut was joined to the workpiece | work. It is sectional drawing in the BB line of FIG. It is sectional drawing in the CC line | wire of FIG. It is a perspective view of the caulking bolt concerning Embodiment 2 of the present invention. It is sectional drawing (cross-sectional view in the DD line of FIG. 11) of the same caulking bolt. It is a top view of a caulking bolt. It is sectional drawing (sectional drawing corresponding to the DD line of FIG. 11) which shows the aspect which joins the same crimping bolt to a workpiece | work. FIG. 12 is a cross-sectional view (a cross-sectional view corresponding to the line DD in FIG. 11) showing a state in which the same caulking bolt is joined to the workpiece. It is sectional drawing in the EE line | wire of FIG. It is sectional drawing in the FF line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Caulking nut 2 Nut main body 3 Screw hole 4 Caulking cylinder 4a Caulking part 5 Annular groove 6 Annular groove outer peripheral surface 7 Arc-shaped recessed part 8 Annular groove inner peripheral surface 9 Annular groove bottom surface 11 Gusset-like rib 15 Work 16 Rising wall 16a Plastic deformation Part 17 Burring hole 31 Caulking bolt 32 Screw part 33 Head part 34 Caulking tube 34a Caulking part 35 Annular groove 36 Annular groove outer peripheral surface 37 Arc-shaped concave part 38 Annular groove inner peripheral surface 39 Annular groove bottom surface 41 Gusseted rib

Claims (4)

A caulking nut joined to a workpiece having a burring hole in which a cylindrical rising wall is formed at the periphery,
A nut body having a screw hole;
A caulking tube that is provided on the seat surface side of the nut body so as to go around the screw hole and is inserted into the burring hole of the workpiece from the rising wall side and caulked to the peripheral edge of the burring hole on the side opposite to the rising wall. And
On the seat surface side of the nut body, an annular groove into which the rising wall of the workpiece is press-fitted is formed so as to go around the caulking cylinder,
On the outer circumferential surface of the annular groove, a plurality of recesses are formed at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
A caulking nut, wherein the rising wall of the workpiece is press-fitted into an annular groove of the nut body, is held by each gusset-shaped rib, and is pressed against each recess of the outer circumferential surface of the annular groove. A caulking nut joining structure joined to a workpiece having a burring hole in which a cylindrical rising wall is formed at the periphery,
The caulking nut includes a nut body having a screw hole, and a caulking portion that surrounds the screw hole provided on the seating surface side of the nut body,
On the seat surface side of the nut body, an annular groove is formed around the crimped portion.
A plurality of recesses are formed on the outer circumferential surface of the annular groove at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The rising wall of the workpiece is press-fitted into the annular groove of the caulking nut, is held by each gusset-like rib, and is pressed against each concave portion of the outer circumferential surface of the annular groove,
A caulking nut joining structure characterized in that a caulking portion of the caulking nut is caulked on a peripheral edge of a burring hole opposite to the rising wall of the workpiece. A caulking bolt joined to a workpiece having a burring hole in which a cylindrical rising wall is formed at the periphery,
A threaded portion;
A head portion provided at a proximal end of the screw portion;
For caulking, which is provided on the seat surface side of the head so as to go around the threaded portion and is inserted into the burring hole of the workpiece from the rising wall side and caulked to the peripheral edge of the burring hole opposite to the rising wall. With a cylinder,
On the seat surface side of the head, an annular groove into which the rising wall of the work is press-fitted is formed so as to go around the caulking cylinder,
A plurality of recesses are formed on the outer circumferential surface of the annular groove at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The caulking bolt, wherein the rising wall of the workpiece is press-fitted into the annular groove of the head, is held by each gusset-shaped rib, and is pressed against each concave portion of the outer circumferential surface of the annular groove. A caulking bolt joining structure joined to a workpiece having a burring hole in which a cylindrical rising wall is formed at the periphery,
The caulking bolt includes a screw portion, a head portion provided at the base end of the screw portion, and a caulking portion that surrounds the periphery of the screw portion provided on the seat surface side of the head portion,
On the seating surface side of the head, an annular groove is formed around the caulking portion.
On the outer circumferential surface of the annular groove, a plurality of recesses are formed at intervals in the circumferential direction,
The portion extending from the inner peripheral surface of the annular groove to the bottom surface of the annular groove has a portion protruding from the inner peripheral surface of the annular groove toward the recess, and a portion protruding from the bottom surface of the annular groove at the portion of the recess. A plurality of continuous gusset-like ribs are formed corresponding to the respective recesses,
The rising wall of the workpiece is press-fitted into the annular groove of the caulking bolt, is held by each gusset-shaped rib, and is pressed against each concave portion of the outer circumferential surface of the annular groove,
A caulking bolt joining structure characterized in that a caulking portion of the caulking bolt is caulked on a peripheral edge of a burring hole opposite to the rising wall of the work.

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