JPH0320607B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a link that is rotatably connected to another member, such as an upper arm or a lower arm in a suspension system of an automobile, and a method for manufacturing the link. .

(Prior Art) In an automobile suspension system, a link such as an upper arm or a lower arm that connects the vehicle body and a wheel knuckle mechanism includes an arm body and a pivot part provided at one end of the arm body. As a forming means, for example, as described in JP-A-59-202915, a cylindrical body is fixed to one end of the arm body by welding. The present invention
The cylindrical body is fixed by caulking. Generally, the means for caulking the cylindrical body to the plate is to form a stepped part on the cylindrical body, and attach the plate to the large diameter part. (Japanese Unexamined Patent Publication No. 54-5859), and one that forms grooves on the inner surface of the cylindrical body to make it easier to bulge out.
-96464) etc. are known.

(Problems to be Solved by the Invention) In the prior art, in which the cylinder is fixed by welding, rust occurs in the welded part due to heating during welding, making it difficult to carry out subsequent rust-proofing treatment. Fixing the cylindrical body by caulking requires a pre-processing step to provide a step or groove in the cylindrical body, and the cylindrical body is formed into a bellows shape, and the bellows-shaped part becomes a hollow bead. There was a problem that it had elasticity and was difficult to caulk firmly.

(Means for Solving the Problems) The present invention has developed a link that firmly fixes a cylindrical body by caulking without using welding means that causes rust, and a manufacturing method thereof. A concentric mounting hole passing through both flanges is provided at one end of the arm body, which has a U-shaped cross section and consists of a web and flanges on both sides of the web. The cylindrical body is fixed to the arm body by forming a solid bead in contact with the outer surface of both flanges, and by bringing the entire end surfaces of the bead and the caulking portion into close contact with the flange. Regarding the manufacturing method, a concentric mounting hole passing through both flanges is provided at one end of the arm main body, which has a U-shaped cross section and is made up of a web and flanges on both sides of the web.A cylinder is fitted into the mounting hole, and the inner circumference The inner periphery of the split mold with narrow annular enlarged diameter parts formed at both ends grips the outer circumferential surface of the cylinder between the two flanges, the inner surface of the cylinder is held down by a mandrel, and the outside of the cylinder is held at a position outside the flanges. The circumferential surface is pressed with a receiving mold, and both ends of the cylinder are pressurized in the axial direction to press fit a part of the cylinder into the enlarged diameter part to form a solid bead, and then both ends of the cylinder are pressed into the solid bead. The cylindrical body is fixed to the arm body by caulking, and the caulked portion and the entire end face of the bead are brought into close contact with the flange.

(Function) In the link of the present invention, the two flanges of the arm body are sandwiched and fixed by the solid bead of the cylinder and the caulked part, so a strong fixed part that does not come loose is formed. It is possible to perform the same function as an integrally formed link. Furthermore, in the manufacturing method of the present invention, a solid bead is formed by using the inner surface of the flange of the arm body as a part of the mold by applying pressure in the axial direction of the cylinder, so that the bead is in close contact with the inner surface of the flange. Next, by crimping both ends of the cylinder, the flange is held between the bead and the crimped portion, forming a strong joint.

(Embodiment) Among the drawings, FIG. 1 shows a first embodiment of the link of the present invention. This link 1 is used as a lower arm in a suspension system of an automobile, and is pivotally connected to an arm body 2 and a vehicle body. A cylindrical body 3 and a ball joint mounting seat 4 are provided.

As shown in FIGS. 2 and 3, the arm body 2 has a U-shaped cross section consisting of a web 5 and flanges 6, 6. At one end, the flanges 6, 6 are bored into short tube edges 7, 7. Mounting holes 8, 8
is formed.

Solid beads 10, 10 are protruded from the circumferential surface of the cylinder 3, and are in contact with the inner surfaces of the flanges 6, 6.
The cylindrical body 3 is fixed to the arm body 2 by clamping the tube edges 7, 7 with the entire end faces of the cylindrical body 3.

The cylindrical body 3 has beads 10, 10 or caulked portions 1.
Although it is possible to fix the arm to the arm body using only one of the methods 1 and 11, in the present invention, both of these methods are used, and since the bead is made solid, a reliable fixed part is formed without bending under the load in the axial direction. ,
Even after long-term use with vibration, the caulked portion will not loosen. Therefore, even if a thin-walled tube and arm body are used as materials for the link, the joint between the arm body and the tube can be made strong, which also helps reduce the weight of the vehicle.

Next, the means for forming this joint portion are shown in FIGS. 4 to 6.
This will be explained using figures.

First, as shown in FIG. 4, a simple cylindrical body 3 is fitted into the mounting holes 8, 8 of the flanges 6, 6,
The outer peripheral surface of the cylinder 33 is pressed between the flanges 6 and 6 by the split molds 20 and 21. Narrow enlarged diameter parts 22, 23 and 24, 25 are formed at both ends of the inner circumference of the split molds 20, 21, and one annular space is formed by the enlarged diameter parts 22, 23. Also 24,
25 forms another annular space.

Next, as shown in FIG.
Punches 34, 35 having mandrels 34, 35 press the tube edges 7, 7 and the exposed parts of the cylinder 3 with 2, 33.
is inserted and pressurizes both ends of the cylinder 3. Due to this pressurization, the split diameter enlarged portions 22, 23, 2 of the cylinder body 3
4, 25 is pushed out into the annular space defined by the enlarged diameter portion and the flanges 6, 6, and
A solid bead 1 that extends outward as shown in the figure.
Form 0,10. Therefore, the flange 6,
The inner surface of 6 constitutes a part of the bead mold. Next, split molds 30 to 33 and punches 34 and 35
are removed to form split molds 30a to 33 as shown in FIG.
Punch 38, 3 for end face caulking using a as a guide
The end faces are swaged by 9 to form swaged portions 11, 11, and cooperate with beads 10, 10 to fix the cylindrical body 3 to the flanges 6, 6.

The punches 34 and 35 described above are integrally provided with mandrels 36 and 37, and one or both of the punches 34 and 35 are provided with an opening equal to the inner diameter of the cylindrical body 3,
A single mandrel passing through these openings and the cylindrical body 3 can be used, and in this way unexpected deformation of the middle part of the cylindrical body 3 can be prevented.

Next, a second embodiment of the link of the present invention and its manufacturing method will be described.

This link is partially designated by the reference numeral 40 in FIG. 8, and the flanges 41, 41 of the link 40 are provided with mounting holes 42, 42, which do not correspond to the tube edge 8 in the first embodiment. Beads 44, 44 are formed on the cylindrical body 43 as in the first embodiment,
The flanges 41, 41 are directly fixed by the beads 44, 44 and the caulked portions 45, 45. Since this fixed part does not have the tube edge 7 like the first embodiment, the resistance against the center runout of the cylinder is weaker than in the first embodiment, but the flanges 41, 41 are made of solid beads. Since it is supported, a strong joint can be obtained even if only the outer circumferential portion 43a of the end portion of the cylinder body 43 is caulked with the portions 45, 45.

The processing order of this embodiment is as shown in FIG.
53, and a punch 54 having a mandrel 55 presses both end surfaces of the cylindrical body 43 to extrude the bead 44. This process is different from the process shown in FIG.
The only difference is that the inner peripheral surface shape of No. 3 does not include a portion corresponding to the tube edge 7. Next, the outer peripheral portions 43a at both ends of the cylinder body 43 are caulked using a caulking punch 56 holding a mandrel 57 to form a caulked portion 45.

The structure of the caulking portions at both ends may be the structure of the caulking portion 11 in the first embodiment in addition to the structure of the caulking portion 45 described above, and in this case, punches 38 and 39 shown in FIG. 7 are used.

(Effects of the Invention) In the link of the present invention, when the cylindrical body is caulked to the arm body, the flange of the arm body is used as a part of the mold to form a bead. Since the bead has a solid structure with no internal gaps, it does not undergo elastic deformation, and therefore the caulked portion does not loosen. Therefore, in this link, the cylinder is fixed with two sets of fixing means, the bead and the caulking part, and since the fixing means is difficult to loosen, an extremely strong and reliable joint can be obtained. Can be done. Therefore, it is possible to use a thin arm body and cylinder body, which is effective in reducing weight.

Furthermore, according to the manufacturing method of the present invention, since the narrow enlarged diameter portions are provided at both ends of the inner circumference of the split die that grips the outer peripheral surface of the cylinder, the cylinder does not bend into a bellows shape.
A solid bead is easily formed, and the cylinder can be reliably caulked to the arm body.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a first embodiment of the link of the present invention, Fig. 2 is a side view of the arm body used in the link of Fig. 1, and Fig. 3 is a sectional view taken along the - line in Fig. 2; 4, 5, 6, and 7 are cross-sectional views showing the manufacturing process of the link shown in FIG. 1, FIG. 8 is a cross-sectional view showing the second embodiment of the link of the present invention, and FIG. FIG. 10 is a sectional view showing the manufacturing process of the link shown in FIG. 8. 2... Arm body, 3, 43... Cylinder body, 10, 44
... Bead, 11, 45... Caulking part, 20, 21,
50, 51...Split mold, 22, 23, 24, 25... Expanded diameter part.

Claims (1)

[Claims] 1. A concentric mounting hole passing through both flanges is provided at one end of the arm main body, which has a U-shaped cross section and is composed of a web and flanges on both sides of the web, and a concentric mounting hole is provided on the outer periphery of the cylindrical body that fits into the mounting hole. , a solid bead in contact with the inner surfaces of both flanges and a solid caulked portion in contact with the outer surfaces of both flanges are formed, and the entire end surfaces of these beads and caulked portions are brought into close contact with the flanges to secure the cylinder to the arm body. Links featuring what you did. 2 At one end of the arm body, which has a U-shaped cross section and consists of the web and the flanges on both sides of the web, provide a concentric mounting hole that passes through both flanges, fit the cylinder into the mounting hole, and insert a width of The inner periphery of the split mold forming a narrow annular enlarged diameter part grips the outer periphery of the cylinder between the flanges, the inner surface of the cylindrical body is held down by a mandrel, and the outer periphery of the cylindrical body is held at a position outside the flanges. Press with a mold,
Both ends of the cylinder are pressurized in the axial direction to press fit a part of the cylinder into the enlarged diameter part to form a solid bead, and then both ends of the cylinder are caulked solidly, and this caulked part and the bead are A method for manufacturing a link, characterized in that the entire end face of the link is brought into close contact with the flange, and the cylindrical body is fixed to the arm body.