JP2003094129A - Rod connection structure and its caulking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection structure of a high-quality rod without rust generation due to water penetration, and to provide its caulking device. SOLUTION: In a rod connection structure, an inner axis material having an axis with circular protrusion and recess formed on the outer circumference and a hollow pipe fitted to an axis of the inner axis material are equipped. In a condition that the inner axis material is fitted to the hollow pipe, the rod is connected with a first caulking part formed by caulking and pressing the outer circumference of the hollow pipe from the axis vertical direction that faces an inner axis having a cross section vertical relative to the axis of nearly a semicircle, and a second caulking part having a cross section vertical relative to the axis of nearly a reverse semicircle. The first and second caulking parts are not situated on the same line in the axis vertical direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rod connecting structure for connecting rods used in, for example, a suspension system and a steering system for automobiles by swaging, and a swaging device therefor.

[0002]

2. Description of the Related Art Conventionally, ball joints have been frequently used for connecting portions of suspension systems and steering systems of automobiles.
Such a ball joint has a spherical ball head 106 and a shaft portion 103 extending from the ball head 106 and having a circumferential convex portion 104 and a concave portion 105 formed on the outer periphery thereof, as shown in FIG. The rod 101 comprises an inner shaft member 102 and a hollow pipe 111 fitted to the shaft portion 103 and fixed by caulking. Further, a ball head 106 of the rod 101 is swingably and rotatably enclosed. A sheet 126 made of synthetic resin having a sheet opening 127 that is held and has an opening at one end;
A substantially cup-shaped housing 121 that encloses the seat 126 and projects the shaft portion 103 of the rod 101 from a housing opening 123 that opens at one end, and an annular retaining ring that is arranged on the inner circumference of the end portion of the housing 121 on the housing opening 123 side. 125 and one boot small opening 132 at the outer circumference of the shaft 103 of the inner shaft member 102, and the other boot large opening 13 at the other end.
3 and a boot 131 for mounting the No. 3 on the outer circumference of the housing 121.

Here, the connection structure of the rod 101 of the ball joint 110 will be described with reference to FIG. 9. The small diameter portion 112 of the hollow pipe 111 is fitted into the convex portion 104 and the concave portion 105 of the inner shaft member 102 to face each other. The static metal mold 161 and the moving metal mold 151 in which a plurality of caulking projection molds 163, 153 are formed on the rod engaging surfaces 162, 152 at intervals in the axial direction are caulked and pressed from the vertical direction.
At this time, the deformed wall of the hollow pipe 111 pressed by the caulking protrusions 163 and 153 causes the concave portion 10 of the inner shaft member 102 to be deformed.
5, the inner shaft member 102 and the hollow pipe 111 were caulked and fixed, and the rod 101 was connected.

[0004]

As described above, the rod 1
By pressing 01 from the direction perpendicular to the opposing axial line and caulking and fixing it, a high coupling strength can be obtained against a load in the axial direction.

However, the hollow pipe 111 before being caulked and pressed
The inner diameter of the small-diameter portion 112 is larger than the outer diameter of the concave portion 105 of the inner shaft member 102 for fitting into the inner shaft member 102. Here, in the hollow pipe 111 pressed from the direction perpendicular to the axis, the deformed meat flows along the concave portion 105 of the inner shaft member 102 to form the caulked portion 114, but in the vicinity located on the horizontal plane passing through the axis, Hollow pipe before crimping and pressing 1
11 inner diameter of the small diameter portion 112 and the concave portion 105 of the inner shaft member 102
Due to the difference from the outer diameter, a surplus portion 116 in which the hollow pipe 111 is not caulked and pressed is generated. Particularly, at the stage of forming the caulking portion 114, the extra portion 116 receives a caulking load from both opposite caulking directions as shown in FIG. 8, so that the hollow pipe 111 is crushed as shown in FIG. 1
A crack 120 may occur on the inner circumference of the inner wall 16. Then, the crack 120 sometimes becomes a crack that extends to the outer peripheral side when the rod 101 is used for a long period of time, and water or the like enters through the crack to cause generation of rust.

Therefore, it is an object of the present invention to solve the above-mentioned problems and to provide a high quality rod connecting structure and a caulking apparatus for the same, which does not cause rust due to intrusion of water or the like.

[0007]

The rod connecting structure of the present invention is as follows.

An inner shaft member having a shaft portion on the outer periphery of which a circumferential convex portion and a concave portion are formed and a hollow pipe fitted to the shaft portion of the inner shaft member are provided, and the inner shaft member is fitted to the hollow pipe. In this state, the rod is formed by connecting the outer periphery of the hollow pipe by caulking and pressing the outer periphery of the hollow pipe to form a first caulking portion having a substantially semicircular cross section perpendicular to the axis and a second caulking portion having an approximately semicircular cross section perpendicular to the axial line. In the connection structure of No. 1, the first caulking portion and the second caulking portion are not located on the same line in the direction perpendicular to the axis.

The rod caulking device of the present invention has the following structure.

It comprises a static die for mounting the rod before crimping, and a dynamic die arranged so as to be capable of advancing and retracting with respect to the static die. The static die and the dynamic die have rods on their end faces facing each other. A semi-cylindrical rod engaging surface is formed to engage with each other, and the static caulking projection die of the static die and the dynamic caulking projection die of the dynamic die that project along the rod engagement surface are spaced in the axial direction. In the caulking forming device for a plurality of rods, the static caulking projecting die and the dynamic caulking projecting die are not located on the same line in the direction perpendicular to the axis.

[0011]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows a ball joint 10 with a rod 1 according to an embodiment of the invention. The ball joint 10 includes an inner shaft member 2 having a spherical ball head 6 and a shaft portion 3 extending from the ball head 6 and having circumferential projections 4 and recesses 5 formed on the outer periphery thereof, and the shaft portion 3 thereof. A rod 1 formed of a hollow pipe 11 fixed by fitting and fitting, and further, a ball head 6 of the rod 1 is swingably and rotatably enclosed, and a seat opening 27 opened at one end is provided. A synthetic resin sheet 26, a substantially cup-shaped housing 21 that encloses the sheet 26 and projects the shaft portion 3 of the rod 1 from a housing opening 23 that opens at one end, and an inner circumference of an end portion of the housing 21 on the housing opening 23 side. Annular retaining ring 2 placed
5, and a boot 31 in which one end boot small opening 32 is mounted on the outer circumference of the boot groove 7 provided near the convex portion 4 and the recess 5 of the shaft portion 3, and the other boot large opening 33 is mounted on the outer circumference of the housing 21. It is configured.

Now, the connecting structure of the ball joint 10, particularly the rod 1, will be described. The rod 1 is caulked and pressed from the direction perpendicular to the axis line in a state where the small diameter portion 12 of the hollow pipe 11 is fitted to the shaft portion 3 forming the circumferential convex portion 4 and the concave portion 5 on the outer periphery of the inner shaft member 2, Inner shaft member 2
And the hollow pipe 11 are caulked and fixed. Due to this caulking and pressing, the recess 5 of the inner shaft member 2 is provided on the outer periphery of the hollow pipe 11.
At a position not located on the same collinear line in the direction perpendicular to the axial line, that is, a first part having a substantially semicircular cross section perpendicular to the axial line on the upper side around a horizontal plane that alternately passes through the axial center with respect to the concave portion 5 formed in the axial direction. On the lower side of the caulking portion 14, a second caulking portion 15 having a substantially inverted semicircular cross section perpendicular to the axis is formed. Further, the crimping end portions 17, 17 located at the circumferential end portions of the first crimping portion 14 and the second crimping portion 15 have a semicircular shape.

Next, a caulking forming device 41 for realizing the connecting structure of the rod 1 will be described with reference to FIG.

Reference numeral 61 denotes a static metal mold for mounting the rod 1 in which the small diameter portion 12 of the hollow pipe 11 is fitted on the shaft portion 3 of the inner shaft member 2, and the upper end surface of which is a semi-cylinder with which the rod 1 is engaged. A rod-shaped engaging surface 62 is formed, and a plurality of caulking protrusions 63 projecting along the rod-engaging surface 62 are formed at intervals in the axial direction. The crimping protruding end portion 64 located at the circumferential end portion of the crimping protruding mold 63 is formed in a semicircular shape. Next, 51 is a moving die which is arranged so as to be able to move forward and backward with respect to the static die 61, and a semi-cylindrical rod engaging surface 52 with which the rod 1 is engaged is formed on the lower end surface thereof. A similar caulking protrusion 53 is formed on the rod engaging surface 52 at a position where a distance half the distance between the caulking protrusions 63 of the static die 61 is shifted in the axial direction. Caulking projection die 53 of this dynamic die 51
The crimping projection end portion 54 located at the circumferential end portion of is also formed in a semicircular shape.

A method of connecting the rods 1 by using the caulking device 41 will be described.

First, as shown in FIG. 4, the shaft portion 3 of the inner shaft member 2 is formed.
The rod 1 in which the small diameter portion 12 of the hollow pipe 11 is fitted in the convex portion 4 and the concave portion 5 of the hollow pipe 11 is conveyed between the static die 61 and the dynamic die 51, and thereafter, as shown in FIG. The crimping protrusion die 63 of 61 is positioned so as to face the recess 5 of the inner shaft member 2, and the rod 1 engages with the rod engagement surface 62 to allow the static die 61
Placed on. Subsequently, the moving die 51 descends, and the hollow pipe 11 is caulked and pressed from the direction perpendicular to the axis as shown in FIG. Here, the lower half part of the hollow pipe 11 is pressed by the static caulking projection mold 63, and the upper half part of the hollow pipe 11 is pressed by the dynamic caulking projection mold 53. Flow. At this time, since the static caulking projecting die 63 and the dynamic caulking projecting die 53 are not positioned on the same line in the vertical direction of the axis, the pressing is applied only from any one direction, so that the flow of the deformed meat does not affect each other. As shown in FIG. 3, the deformed wall of the hollow pipe 11 largely flows in the direction not pressed. Then, as shown in FIGS. 2A and 2A, the first caulking portion 1 having an approximately semicircular cross section perpendicular to the axial direction upward with a horizontal plane alternately passing through the axial center of the concave portion 5 formed in the axial direction as the center.
4, the second caulking portion 15 having a substantially inverted semicircular cross section perpendicular to the axial line on the lower side
Are alternately formed on the outer circumference of the hollow pipe 11 and the rods 1 are connected.

Therefore, as described above, since the first caulking portion 14 and the second caulking portion 15 are not located on the same line in the direction perpendicular to the axis, the flow of the deformed meat of the hollow pipe 11 when caulking and pressing does not affect each other, so that the hollow The pipe 11 is not crushed and cracks are not generated.

[0019]

As described above, according to the rod connecting structure of the present invention, the inner shaft member having the shaft portion in which the circumferential convex and concave portions are formed on the outer periphery and the shaft portion of the inner shaft member are fitted. With a hollow pipe to do, with the inner shaft member fitted to the hollow pipe,
A connecting structure for a rod that caulks and presses the outer circumference of a hollow pipe from the opposite axial direction to form a first caulking portion having a substantially semicircular cross section perpendicular to the axial line and a second caulking portion having a substantially semicircular cross section perpendicular to the axial line. In, since the first caulking portion and the second caulking portion are not on the same line in the direction perpendicular to the axis, the flow of the deformed meat of the hollow pipe during caulking does not affect each other, so that the hollow pipe is crushed and cracks occur. Without
High quality can be maintained.

Further, according to the apparatus for caulking a rod of the present invention, it comprises a static metal mold on which the rod before caulking is placed and a moving metal mold which is arranged so as to be movable back and forth with respect to the static metal mold. A semi-cylindrical rod engaging surface for engaging a rod is formed on end faces of the die and the moving die that face each other, and a static caulking projection die and a moving die of the static die that protrudes along the rod engaging surface. In the rod crimping forming apparatus in which a plurality of dynamic caulking dies of the die are formed at intervals in the axial direction, since the static caulking dies and the dynamic caulking dies are not located on the same line in the direction perpendicular to the axis, The connecting structure of the rods can be easily realized.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional plan view showing a ball joint using a rod having a connection structure according to an embodiment of the present invention.

2A and 2B show a connecting structure of rods according to an embodiment of the present invention, in which FIG. 2A is a plan view and FIG.

FIG. 3 is an enlarged explanatory view of a B part in FIG. 2A showing a forming process of a caulking part according to the embodiment of the present invention.

FIG. 4 is a partial cross-sectional front view showing a first step in which the rod is caulked and pressed by the caulking device for a rod according to the embodiment of the present invention.

FIG. 5 is a partial cross-sectional front view showing a second stage in which the rod is caulked and pressed by the caulking device for a rod according to the embodiment of the present invention.

FIG. 6 is a partial cross-sectional front view showing a third stage in which the rod is caulked and pressed by the caulking device for a rod according to the embodiment of the present invention.

FIG. 7 shows a ball joint using a rod of a conventional connecting structure, (A) is a partial sectional plan view, and (A) is a DD sectional view of (A).

FIG. 8 is an enlarged explanatory view of an E portion of FIG. 10A showing a conventional forming process of the caulking portion.

FIG. 9 is a partial sectional front view showing a step of crimping and pressing the rod by a conventional rod crimping and forming apparatus.

[Explanation of symbols]

1 rod 2 Inner shaft member 3 shafts 4 convex 5 recess 11 hollow pipe 14 First caulking part 15 Second caulking part 51 Dynamic mold 61 static mold 52, 62 Rod engaging surface 53 Dynamic caulking protrusion type 63 Static caulking protrusion type

Claims (2)

[Claims] 1. Circumferential projections (4) and recesses (5) on the outer circumference
An inner shaft member (2) having a shaft portion (3) formed with a hollow pipe (1) fitted to the shaft portion (3) of the inner shaft member (2).
1), and an inner shaft member (2) in the hollow pipe (11).
In the fitted state, the outer periphery of the hollow pipe (11) is caulked and pressed from the opposite vertical direction to the first caulking portion (14) having a substantially semicircular cross section perpendicular to the axial line and the second caulking section having a substantially semicircular cross section perpendicular to the axial line. In the rod connecting structure for forming and connecting the crimped portion (15), the first crimped portion (14) and the second crimped portion (15) are not located on the same line in the vertical direction of the axis. Connection structure. 2. A static metal mold (61) on which the rod (1) before being swaged is placed, and a dynamic metal mold (51) arranged so as to be movable back and forth with respect to the static metal mold (61). The mold (61) and the moving mold (51) have semi-cylindrical rod engaging surfaces (62) for engaging the rods (1) with end surfaces facing each other.
(52) is formed, and the rod engaging surfaces (62), (52)
The static crimping protrusion (63) of the static die (61) and the dynamic crimping protrusion (5) of the dynamic die (51) protruding along the
3) In a caulking device for a plurality of rods formed at intervals in the axial direction, the static caulking projecting die (63) and the dynamic caulking projecting die (53) are not located on the same axis vertical direction. A device for caulking rods.