JP2002295569A - Strut type outer shell unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-productivity strut type outer shell unit. SOLUTION: In the strut type outer shell unit 10 where a knuckle bracket 7 is mounted on an outer shell 3, the bottom 31 of the shell 3 is blocked by a closing process, the knuckle bracket 7 is made of a sheet of plate with no reinforced material to connect a pair of flanges 7b, the top end 7e of the bracket 7 has a top end weld part 21 stuck on the shell 3, and a bottom end weld part 22 where the bottom end 7f of the knuckle bracket 7 is fixed on the shell 3 and an unwelded part 23 where the bottom end 7f of the knuckle bracket 7 is not fixed on the shell 3 by welding are arranged side by side along the circumference of the shell 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved strut type outer shell unit for suspending a vehicle.

[0002]

2. Description of the Related Art A strut type shock absorber functions as a structural member for positioning a wheel as a part of a suspension member in addition to an original function of generating a damping force.

FIGS. 9 (a), 9 (b) and 9 (c) show an outer shell unit 10 constituting a conventional strut type shock absorber. The outer shell unit 10 has a cylindrical shape incorporating a damping force generating mechanism. And a knuckle bracket 7 attached to the outer shell 3 and connected to a knuckle.

The knuckle bracket 7 is used for the outer shell 3.
And then fixed by welding. The upper and lower ends 7e and 7f of the single-plate knuckle bracket 7 are fixed to the outer shell 3 by welding portions 21 and 22, respectively.

[0005] A lower cap 17 is attached to an opening at the lower end of the outer shell 3. Lower cap 17
Is welded to the lower end of the outer shell 3 by the lower end welding portion 22 together with the lower end 7f of the knuckle bracket 7, and the bottom of the outer shell 3 is sealed.

[0006]

However, such conventional strut type outer shell unit 10
Since the bottom portion of the outer shell 3 is hermetically sealed by the lower end welded portion 22, the lower end welded portion 22 needs to be provided over the entire circumference of the outer shell 3 and the cycle time of the welding line is lengthened. Since the lower end welded portion 22 requires not only strength quality but also hermeticity, it is difficult to increase the welding speed.

The present invention has been made in view of the above problems, and has as its object to provide a highly productive strut type outer shell unit.

[0008]

According to a first aspect of the present invention, there is provided a strut type outer shell unit including a cylindrical outer shell having a built-in damping force generating mechanism, and a knuckle bracket attached to the outer shell and connected with a knuckle. Apply.

The bottom portion of the outer shell is closed by a closing process, and the knuckle bracket has a fitting portion fitted to the outer shell and a pair of flange portions sandwiching the knuckle. A single-plate type without a reinforcing member, the upper end of the knuckle bracket is fixed to the outer shell by welding, and the lower end of the knuckle bracket is fixed to the outer shell by welding. A non-welded portion that is not fixed to the shell by welding is provided side by side in the circumferential direction of the outer shell.

According to a second aspect of the present invention, a bottom portion of the outer shell is closed by a closing process, the knuckle bracket has a fitting portion fitted to the outer shell and a pair of flange portions sandwiching the knuckle. A two-plate type provided with a reinforcing member that connects the flange portions of the outer shell has a lower end welded portion fixed to the outer shell by welding at the lower end of the knuckle bracket, and a non-welded portion not fixed to the outer shell by welding. It is characterized by being provided side by side in the circumferential direction.

A third invention is characterized in that in the first or second invention, a knuckle bracket is welded to the outer shell at a high speed by a vertical downward welding method.

[0012]

According to the first invention, in the single-plate knuckle bracket, since the bending rigidity of the knuckle bracket is secured by the upper end welded portion, it is necessary to increase the bending rigidity of the knuckle bracket by the lower end welded portion. And the lower end welded portion can be partially formed in the circumferential direction of the outer shell.

Further, since the bottom of the outer shell is sealed by the closing process, it is not necessary to seal the bottom with a lower end weld, and the lower end weld is formed partially in the circumferential direction of the outer shell. Becomes possible.

By shortening the welding length of the lower end welded portion, the cycle time required to form one outer shell unit on the welding line can be shortened, the productivity can be increased, and the cost of the product can be reduced. To be peeled off.

According to the second aspect of the present invention, the bending rigidity of the two-plate knuckle bracket is ensured by the reinforcing member between the flange portions. Therefore, it is necessary to increase the bending rigidity of the knuckle bracket by the lower end welded portion. Therefore, the lower end welded portion can be formed partially in the circumferential direction of the outer shell.

Further, since the bottom of the outer shell is sealed by a closing process, it is not necessary to seal the bottom with a lower end weld, and the lower end weld is formed partially in the circumferential direction of the outer shell. Becomes possible.

By shortening the welding length of the lower end welding portion, the cycle time required to form one outer shell unit in the welding line can be shortened, the productivity can be increased, and the cost of the product can be reduced. To be peeled off.

According to the third aspect, since the bottom of the outer shell is hermetically sealed by the closing process, it is not necessary to seal the bottom of the outer shell by welding, and high-speed welding is performed by a vertical downward welding method. Cycle time of the welding line can be shortened.

[0019]

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

As shown in FIG. 1, a strut type shock absorber 1 includes a rod 2 connected to a vehicle body, an outer shell 3 connected to a knuckle (not shown) supporting an axle, and an outer shell 3. A rod guide 9 that slidably supports the rod 2, an inner tube 4 that defines an oil reservoir 18 partially filled with gas inside the outer shell 3, and an inner tube 4 that is connected to the tip of the rod 2. , A piston valve 11 for generating a damping force during an extension stroke.
And a base valve 12 that generates a damping force in a contraction stroke.

In the extension stroke in which the rod 2 moves upward, the upper oil chamber 16 is pressurized, the hydraulic oil flows into the lower oil chamber 17 through the piston valve 11, and a damping force is generated. At this time,
Hydraulic oil corresponding to the retreated amount of the rod 2 opens the base valve 12 from the oil reservoir 18 and flows into the lower oil chamber 17 with almost no resistance.

In the compression stroke in which the rod 2 moves downward, the hydraulic oil in the lower oil chamber 17 opens the piston valve 11 and flows into the upper oil chamber 16 with almost no resistance. At this time, the hydraulic oil corresponding to the intrusion of the rod 2 flows from the lower oil chamber 17 through the base valve 12 into the oil reservoir 18 to generate a damping force.

The outer shell unit 10 of the strut type shock absorber 1 includes an outer shell 3, a spring guide 6 for receiving a lower end of a suspension spring (not shown), and a knuckle bracket 7 to which a knuckle is connected. It performs the function of positioning the wheels.

In the middle of the outer shell 3, an annular stepped portion 35 is formed so as to protrude by bulging. The spring guide 6 is press-fitted into the stepped portion 35 and fixed. Thus, there is no need to weld the spring guide 6 to the outer peripheral surface 3a of the outer shell 3.

The spring guide 6 has a fitting portion 6a fitted to the outer shell 3 and a seat portion 6b for receiving the lower end of the suspension spring, and is integrally formed by press working.

The outer shell 3 has a cylindrical main body 30,
The main body 30 has a bottom 31 for closing the lower end. The bottom 31 of the outer shell 3 is formed integrally with the main body 30 of the outer shell 3 by a plastic working called a closing work. Thereby, the sealing of the bottom 31 of the outer shell 3 is ensured, and there is no need to seal the bottom 31 by welding.

FIG. 2 shows a bottom portion 31 formed by a closing process.
Is shown. The closing machine includes a chuck 42 for holding a work 41 made of a pipe material, a metal core 44 disposed coaxially with the work 41 via a holding rod 43 inside the work 41, and a predetermined offset amount with respect to the work 41. The mold includes a mold 45 that is driven to rotate around an axis having S, and a heating coil 46 that heats the mold 43. Work 4
1 and the cored bar 44 and the mold 45 are driven to rotate in the same direction.

The mold 45 has a cylindrical inner peripheral surface 45a which is hollowed into a cylindrical shape.
And a curved surface 45b depressed into a substantially spherical shape.

The cored bar 44 has a cylindrical outer peripheral surface 44a,
It has a curved surface 44b protruding in a substantially spherical shape, and a concave portion 44c depressed at the center of the curved surface 44b.

The closing process is performed by the work 41 and the core 4
While rotating the mold 4 and the mold 45 in the same direction, the mold 45 is pressed against the work 41 by the force P, so that the opening end of the work 41 is gradually narrowed between the mold 45 and the core 44, and the conical cylinder A bottom 31 is formed which is closed by being reduced in diameter. The bottom 31 is inclined at an angle α with respect to a plane perpendicular to the central axis O, and this angle α is, for example, 30 ° (π
/ 6 rad).

The central portion of the bottom 31 is closed by squeezing the work 41 between the mold 45 and the core 44. At this time, the convex portion 34 protruding into the concave portion 44c of the metal core 44 is formed on the work 41. By providing the convex portion 34 protruding from the bottom portion 31 to the inside of the outer shell 3, the bottom portion 31 is provided.
Can be reliably closed.

On the other hand, the knuckle bracket 7 includes a fitting portion 7a fitted to the outer shell 3, a pair of flange portions 7b for holding the knuckle, and a cut-and-raised hose bracket 7
g. Bolt holes 7c and 7d are formed in each flange portion 7b, and a knuckle is fastened to the knuckle bracket 7 through two bolts inserted through the bolt holes 7c and 7d. Each of the bolt holes 7c and 7d is drilled after the knuckle bracket 7 is fixed to the outer shell 3 by welding to ensure dimensional accuracy. The knuckle bracket 7 is a single plate type having no reinforcing member between the flange portions 7b.

The knuckle bracket 7 is for the outer shell 3
And then fixed by welding. The lower end of the outer shell 3 is narrowed down by a closing process, so that the outer shell 3 can be smoothly pressed into the outer shell 3.

The single-plate type knuckle bracket 7 has upper and lower ends 7e and 7f fixed to the outer shell 3 by welding portions 21 and 22, respectively.

As shown in FIGS. 3B and 3C, the upper end weld 21 is formed over the entire outer shell 3. That is, the upper end welded portion 21 is formed in a continuous annular shape without interruption in the circumferential direction of the outer shell 3.

As shown in FIGS. 3A and 3B, the lower end welded portion 22 extends in a C-shape and is partially formed in the outer shell 3 in the circumferential direction. That is, the lower end welded portion 22 where the lower end 7 f of the knuckle bracket 7 is welded to the outer shell 3 and the non-welded portion 23 where the lower end 7 f of the knuckle bracket 7 is not welded to the outer shell 3 are arranged in the circumferential direction of the outer shell 3. .

As shown in FIGS. 4 (a), 4 (b) and 4 (c), in forming the upper end welded portion 21, the torch 61 of the arc welding machine uses the outer peripheral surface 3a of the outer shell 3 and the knuckle bracket. 7 are directed to the corners between the upper ends 7e and welded by a vertical downward welding method. In the vertical downward welding method, the outer shell 3 is provided with a central axis O that is disposed substantially horizontally.
Rotate it around so that the torch 61 of the arc welding machine is directed to the side of the outer shell 3. The rotation direction of the outer shell 3 is set so that the portion of the outer shell 3 facing the torch 61 rises as indicated by the arrow in FIG. 4B.

A horizontal plane including the center axis O of the outer shell 3 is defined as a horizontal reference plane X. A vertical plane including the center axis O of the outer shell 3 is defined as a vertical reference plane Y. The extension of the torch 61 of the arc welding machine is the outer peripheral surface 3 of the outer shell 3.
The point that intersects with a is referred to as a welding point W.

Whether the welding point W is located on the horizontal reference plane X,
Alternatively, the offset is performed so as to be located above the horizontal reference plane X by a predetermined length Lx. In the present embodiment, the outer diameter of the outer shell 3 is about 45 mm, and the offset amount Lx is set in a range of 0 to 10 mm.

The welding point W has a predetermined length L from the vertical reference plane Y.
offset by y. As a condition of the vertical downward welding method, the welding points W are arranged such that the vertical offset amount Lx is smaller than the horizontal offset amount Ly.

The torch angle θx at which the torch 61 is inclined upward with respect to the horizontal reference plane X is set to be smaller than the torch angle θy inclined with respect to the vertical reference plane Y.
In the present embodiment, the torch angle θx is 0 to 30 ° (0 to 30 °).
π / 6 rad).

This vertical downward welding method uses the outer shell 3
Of the torch 61, the rotation speed of the outer shell 3, the torch angle θx, and the offset L
By setting x arbitrarily and balancing the welding speed and the dripping speed of the molten metal, a welding speed higher than the capability of a welding machine obtained by a conventionally used downward welding method can be obtained.

As shown in FIGS. 5 (a) and 5 (b), in forming the lower end welded portion 22, the torch 61 of the arc welding machine includes the lower end 3b of the outer shell 3 and the lower end 7f of the knuckle bracket 7. It is directed to the corner between and is welded by a vertical downward welding method. In the vertical downward welding method, the outer shell 3 is rotated around a central axis O arranged substantially horizontally. The rotation direction of the outer shell 3 is set so that the portion of the outer shell 3 facing the torch 61 rises as indicated by an arrow in FIG.

Whether the welding point W is located on the horizontal reference plane X,
Alternatively, the offset is performed so as to be located above the horizontal reference plane X by a predetermined length Lx. In the present embodiment, the outer diameter of the outer shell 3 is about 45 mm, and the offset amount Lx is set in a range of 0 to 10 mm.

The torch angle θx at which the torch 61 is inclined upward with respect to the horizontal reference plane X is 0 to 15
° (0 to π / 12 rad).

The operation of the embodiment of the present invention configured as described above will now be described.

When the vehicle is running, a load from the wheels acts on the knuckle bracket 7 via the knuckle. Since the single-plate type knuckle bracket 7 does not have a reinforcing member between the flange portions 7b, a stress is applied to the upper end weld portion 21 by the load from the knuckle to bend and deform it. By providing the upper end weld portion 21 over the entire periphery of the outer shell 3, the bending rigidity of the knuckle bracket 7 is sufficiently ensured. In addition, the upper end welding part 21 which fixes the upper end 7e of the knuckle bracket 7 to the outer shell 3 may be partially formed according to required strength.

Since the bending rigidity of the knuckle bracket 7 is ensured by the upper end welding portion 21 in this manner, it is not necessary to increase the bending rigidity of the knuckle bracket 7 by the lower end welding portion 22. Partial formation is possible.

Further, since the bottom 31 of the outer shell 3 is sealed by the closing process, it is not necessary to seal the bottom 31 with the lower end welded portion 22. Partial formation is possible.

Since the lower end welded portion 22 is not required to be hermetically sealed, it is possible to increase the welding speed by using the vertical downward welding method.

As described above, the welding length of the lower end welding portion 22 is shortened and the welding speed is increased, so that the cycle time required to form one outer shell unit 10 on the welding line is shortened, and the productivity is reduced. Can be enhanced. In addition, by reducing the welding length, consumption of auxiliary materials such as wires, gas, and electricity used for welding can be suppressed, and the cost of the product can be reduced.

The welding length of the lower end welding portion 22 and the position at which it is formed are arbitrarily set according to conditions such as the size of the knuckle bracket 7, the rib shape, the plate thickness, and the welding state.

As another embodiment, as shown in FIG. 6, for example, the lower end welded portion 22 may be formed in a semicircular arc shape and arranged on the opposite side to the flange portion 7b.

For example, as shown in FIG. 7, two lower end welds 22a and 22b are formed in a divided manner, one lower end weld 22a is arranged on the opposite side to the flange 7b, and the other lower end weld 22a and 22b are formed. 22b may be arranged to connect the base end of the flange 7b.

In another embodiment shown in FIGS. 8 (a) and 8 (b), the knuckle bracket 7 includes a flange 7b.
A cylindrical two-plate type in which a reinforcing member 40 is provided therebetween is used. Reinforcing member 4 having a U-shaped cross section
Numerals 0 are fixed between the flange portions 7b to increase the rigidity of the knuckle bracket 7.

After the two-plate knuckle bracket 7 is pressed into the outer shell 3, only the lower end 7 f is fixed to the outer shell 3 by the welded portion 42.

The lower end weld 42 extends in a C-shape and is partially formed in the circumferential direction of the outer shell 3. That is, the lower end welding portion 42 where the lower end 7f of the knuckle bracket 7 is welded to the outer shell 3 and the knuckle bracket 7
And a non-welded portion 43 whose lower end 7 f is not welded to the outer shell 3 is arranged in the circumferential direction of the outer shell 3.

The two-plate knuckle bracket 7 is
Since the reinforcing member 40 is provided between the flange portions 7b, the stress is dispersed by being press-fitted into the outer shell 3, and the upper and lower ends 7e, 7f of the knuckle bracket 7 are secured to secure the bending rigidity of the knuckle bracket 7. It is not necessary to fix the outer shell 3 over the entire circumference.

Further, since the bottom 31 of the outer shell 3 is sealed by the closing process, it is not necessary to seal the bottom 31 with the lower end welded portion 42. Partial formation is possible.

Further, since the bottom 31 of the outer shell 3 is sealed by the closing process, it is not necessary to seal the bottom 31 with the lower end weld 24, and the lower end weld 42 is provided in the circumferential direction of the outer shell 3. Partial formation is possible.

Since the lower end welded portion 42 is not required to be hermetically sealed, it is possible to increase the welding speed by using the vertical downward welding method.

As described above, the welding length of the lower end welding portion 42 is shortened and the welding speed is increased, so that the cycle time required to form one outer shell unit 10 on the welding line is shortened, and the productivity is reduced. Can be enhanced. In addition, by reducing the welding length, consumption of auxiliary materials such as wires, gas, and electricity used for welding can be suppressed, and the cost of the product can be reduced.

Further, in this embodiment, the cycle time of the welding line can be greatly reduced by eliminating the upper end welded portion for fixing the upper end 7e of the knuckle bracket 7 to the outer shell 3. As another embodiment, an upper end welded portion for fixing the upper end of the knuckle bracket to the outer shell may be formed partially according to the required strength.

As another embodiment, for example, as shown in FIG. 9, the lower end welded portion 42 may be formed in a semicircular arc shape, and may be arranged on the side opposite to the flange portion 7b.

Further, for example, as shown in FIG. 10, the lower end welded portion 42 may be formed in a semicircular arc shape and arranged so as to connect the base end of the flange portion 7b.

Further, as shown in FIG. 11, for example, the lower end welded portion 42 may be formed in a C-shape and arranged so as to connect the base end of the flange portion 7b.

As shown in FIG. 12, for example, two lower end welds 42a and 42b are formed by division, one lower end weld 42a is arranged on the side opposite to the flange 7b, and the other lower end weld 42a, 42b is formed. 42b may be arranged to connect the base end of the flange 7b.

It is apparent that the present invention is not limited to the above-described embodiment, and that various changes can be made within the scope of the technical concept.

[Brief description of the drawings]

FIG. 1 is a sectional view of a shock absorber according to an embodiment of the present invention.

FIG. 2 is a view showing a process of forming a bottom portion by a closing process.

FIG. 3 is a three side view of the outer shell unit.

FIG. 4 is a view showing a method of high-speed welding the upper end of the knuckle bracket to the outer shell.

FIG. 5 is a view showing a method of high-speed welding the lower end of the knuckle bracket to the outer shell.

FIG. 6 is a plan view of an outer shell according to another embodiment viewed from below.

FIG. 7 is a plan view of an outer shell according to another embodiment viewed from below.

FIG. 8 is a two-sided view of an outer shell showing another embodiment.

FIG. 9 is a plan view of an outer shell according to another embodiment viewed from below.

FIG. 10 is a plan view of an outer shell according to another embodiment viewed from below.

FIG. 11 is a plan view of an outer shell according to another embodiment viewed from below.

FIG. 12 is a plan view of an outer shell according to another embodiment viewed from below.

FIG. 13 is a three side view of an outer shell unit showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shock absorber 3 Outer shell 6 Spring guide 7 Knuckle bracket 7b Flange part 7e Knuckle bracket upper end 7f Knuckle bracket lower end 10 Outer shell unit 21 Upper end welded part 22 Lower end welded part 31 Bottom part 35 Stepped part 40 Reinforcement member 42 Lower end welded part

Claims (3)

[Claims] 1. A strut type outer shell unit comprising: a tubular outer shell having a damping force generating mechanism built therein; and a knuckle bracket attached to the outer shell and connected to a knuckle, wherein a bottom of the outer shell is closed. The knuckle bracket is closed by processing, the knuckle bracket has a fitting portion fitted to the outer shell, and a pair of flange portions sandwiching the knuckle, and the knuckle bracket is a single plate having no reinforcing member between the pair of flange portions. The upper end of the knuckle bracket has an upper end welded portion that is fixed to the outer shell by welding.The lower end of the knuckle bracket has a lower end welded portion that is fixed to the outer shell by welding, and is fixed to the outer shell by welding. The non-welded part that is not Strut outer shell unit, characterized in that are side by side provided. 2. A strut type outer shell unit comprising: a tubular outer shell having a built-in damping force generating mechanism; and a knuckle bracket attached to the outer shell and connected to a knuckle, wherein the outer shell has a bottom formed by closing. Closed, the knuckle bracket has a fitting portion fitted to the outer shell and a pair of flange portions sandwiching the knuckle, and the knuckle bracket is a two-plate type provided with a reinforcing member connecting the pair of flange portions, A strut type wherein a lower end welded portion fixed to the outer shell by welding and a non-welded portion not fixed to the outer shell by welding are provided at a lower end of the knuckle bracket in a circumferential direction of the outer shell. Outer shell unit. 3. The strut type outer shell unit according to claim 1, wherein the knuckle bracket is welded to the outer shell at a high speed by a vertical downward welding method.