JP3256577B2 - Front wheel support device for motorcycles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front wheel support device used for a motorcycle, and more particularly, to a front wheel support device having a front fork having a feature in a wheel shaft support portion.

[0002]

2. Description of the Related Art Conventionally, as a front wheel supporting device for supporting a front wheel of a motorcycle, two tubes are combined in a telescopic shape so that an inner cylinder and an outer cylinder make a stroke while contacting each other. In addition, there is a so-called telescopic type in which a metal ring is provided on each of the outer cylinders, and a front fork configured to make a stroke while the inner cylinder and the outer cylinder contact each other at the position of the metal ring to support a wheel shaft of a front wheel. On the other hand, as a structure for supporting the front wheel with the front fork, a hole is formed at the lower end of the front fork for fitting the wheel shaft of the front wheel, and a wheel shaft is erected between the holes (Japanese Patent Laid-Open No. No. 61-178237), and a concave portion for detachably fitting the wheel shaft on the front side of the lower portion (not the lower end) of the front fork. Type to fix the wheel shaft (Japanese Unexamined Patent Publication No. 61-92981)
There was one.

[0003]

However, the front wheel supporting device of the type in which the wheel shaft is supported by the lower end of the front fork supports the wheel shaft substantially on the axis of the front fork. In the case of such a telescopic type, there is an advantage that the contact portion between the inner cylinder and the outer cylinder, for example, a reaction force from the ground applied to the metal ring can be reduced,
Since the supporting portion is provided at the lower end of the front fork, there is a problem that the length of the front fork itself is limited, and as a result, the stroke length is limited. In addition, the front wheel support device of the type that supports the wheel shaft on the front side of the lower portion of the front fork has no limitation on the lower end, so that the length of the front fork itself, that is, the stroke length of the front fork can be sufficiently secured. Although it has an advantage, since the position for supporting the wheel shaft is offset forward from the axis of the front fork, there is a problem that the reaction force from the ground on the contact portion between the inner cylinder and the outer cylinder, for example, the metal ring increases. was there.
Therefore, the present invention solves the above-described problems of the conventional front wheel support device for a motorcycle, allows the front fork to have a sufficient length, and has an inner cylinder and an outer cylinder. Motorcycle having a front fork that does not increase the reaction force from the ground on the contact portion, for example, the metal ring
And its object is to provide a front wheel support device.

[0004]

The above object is achieved.
The motorcycle front wheel support device of the present invention
Front fork with the inner cylinder slidably fitted to the outer cylinder
In front of the motorcycle that supports the wheel shaft at the bottom of the motorcycle
In the wheel support device, above the lower end of each front fork
Of each front fork on the inner part facing each other
A pair of left and right bosses protruding from the outer wall are formed integrally,
Corresponding freon and fork center on front side of boss
On the axis, while forming a vertically long mating surface facing forward,
Both ends of the wheel shaft at the center in the vertical direction of this mating surface
Form a semicircular recess that allows the front to be detachably fitted from the front
And a surface joined to the mating surface of the boss portion,
A pair of holdings in which a concave portion and a semicircular concave portion forming a pair are formed.
A member is provided, and both ends of the wheel shaft are
Each holding part is attached to each boss from the front side while fitted in the recess.
Material and cover it from above and below the wheel shaft.
Bolt that penetrates the holding member is screwed into the screw provided on the boss
Then, the holding member is joined to the boss to
Is supported by the front fork.
And

[0005]

The front wheel supporting device for a motorcycle constructed as described above is arranged so that the front wheel supporting device is positioned above the lower end of each front fork.
Protruding from the outer wall of each front fork on the facing inner part
Formed on a pair of left and right bosses integrally formed
From the front of the front fork into the
The shaft ends are fitted together and then from the front
It has a surface to be joined to the mating surface of the boss,
A pair of holding members formed with a pair of semicircular recesses
Over the wheel shaft, and
Screw the bolt that passes through the holding member to the screw provided on the boss.
And the holding member is joined to the boss to
Support the ft on the front fork.

[0006]

EXAMPLES Hereinafter, automatic according to the present invention with reference to the accompanying drawings
One embodiment of a front wheel support device for a motorcycle will be described. FIG. 1 is a partially cut-away schematic side view showing a main part of a motorcycle using a front fork constituting a front wheel support device for a motorcycle according to the present invention, and FIG. 2 shows details of a combined state of a front fork and a front wheel. FIG. 3 is a schematic sectional view of a boss portion and a holding member showing details of a support portion of the wheel shaft. In the figure, reference numeral 1 denotes a motorcycle, which is
A head pipe 2 having a steering shaft (not shown) rotatably fixed thereto and a pair of front forks 3, 3 are connected by an under bracket 4 and an upper bracket 5, and a front wheel 6 is supported between the front forks 3, 3. It is configured as follows.

The front fork 3 slidably fits the inner cylinder 7 to the outer cylinder 8 and supports a load by supporting a load with a spring penetrating through the inner cylinder 7 and an oil-type shock absorber formed inside. It is of the so-called Celiani type, configured to absorb. In the figure, reference numeral 9 denotes a hollow cylinder whose upper part is slidably fitted into the inner cylinder 7 and whose lower part is fixed to the bottom of the outer cylinder 8 with bolts 9a. In accordance with the expansion and contraction, the oil flows between another oil chamber (not shown) provided inside the cylinder 9, the oil chamber 10, and the inner cylinder 7 to absorb the shock. The inner tube 7 is formed by screwing a sliding tube 7b onto a hollow support tube 7a which is formed in a tapered shape so as to increase in diameter from both ends toward a substantially central direction. An annular metal ring 7c is provided below. The support tube 7a is preferably formed of a light metal material such as aluminum, and such a material has the effect of reducing the weight of the front fork. The outer cylinder 8 is formed in a hollow cylindrical shape that opens upward, and an annular metal ring 8a and an annular oil seal 8b are fitted to the enlarged diameter portion at the upper part thereof and fixed with a circlip (no symbol). An annular dust seal 8c is provided at the upper end. The inner cylinder 7 is fitted to the outer cylinder 8 configured as described above so as to be in contact with the positions of the metal rings 7c and 8a so as to be slidable, and is exposed to the outside of the sliding tube 7b constituting the inner cylinder 7. A cylindrical protective cover 11 made of a suitable material such as resin is
The front fork 3 is fixed to the upper end of the front fork. The front wheel 6 is supported at the lower part of the front fork 3. The upper part of the front fork 3, specifically, the maximum diameter portion of the support pipe 7 a constituting the inner cylinder 7 is fixed by the under bracket 4.

Hereinafter, the support portion of the front fork 3 for supporting the front wheel will be described. The inner part of the surface of the outer cylinder 8 constituting the above-described front fork 3, specifically, the front fork 3
A boss portion formed with an arc-shaped concave portion 13a on the opposite side thereof to which the end of the wheel shaft 12 can be removably fitted.
13 are integrally formed. Recess of the boss 13 described above
After fitting the end of the wheel shaft 12 to 13a, cover the holding member 14 formed substantially in the same shape as the boss 13 and firmly fix the boss 13 and the holding member 14 with bolts 15,15. That is, the wheel shaft 12, that is, the wheel shaft
The front wheel 6 mounted on the ball bearing 12 via a ball bearing 16 is held by the front fork 3. The front wheel 6 mentioned above
The wheel shaft 12 comprises a wheel 17 and a tire 18.
Is inserted into the hub 12a of the wheel 17 from its left end.
And is fitted to a bearing provided on the hub 12a.
Is fixed with a top 19. In the drawing, reference numeral 20 denotes an annular dust seal, and reference numeral 21 denotes an annular positioning collar, both of which are fixed to the wheel shaft 12 side. In the figure, reference numeral 22 denotes a circlip for fixing an outer member (no symbol) of the ball bearing 16 to the wheel, and is fixed to the wheel 17 side.

In this embodiment, the front fork constituting the front wheel support device is described as a Ceriani type one. However, the configuration of the front fork is not limited to this, and a pair of front forks can be positioned relative to each other. Any structure may be used as long as the boss portion for mounting the wheel shaft is provided on the surface to be formed, and for example, an upright type having another structure may be used.

In the front fork constituting the front wheel supporting device of the present embodiment, the wheel shaft is provided with a boss portion integrally provided above the lower end of the front fork.
Since the configuration is such that the front fork is held at 12, the front fork can have a sufficient length, and the inner cylinder can be separated into a slide tube and a support tube. In the front fork constituting the front wheel support device of the present embodiment, the inner cylinder is divided into a sliding tube and a support tube,
Expanding the diameter of the support tube from both ends toward the substantially central direction,
Since the maximum diameter portion is configured to be held by the under bracket, there is an effect that the rigidity of the portion held by the under bracket to which a strong bending moment is normally applied by the front fork can be increased.

[0011]

The front wheel supporting device for a motorcycle according to the present invention faces each other above the lower end of each front fork.
Projecting from the outer wall of each front fork
A pair of left and right bosses are integrally formed, and the front of each boss is
On the center axis of the corresponding Freon and fork
Form a vertically long mating surface that faces
Both ends of the wheel shaft are attached and detached from the front side at the center in the direction
Form a semicircular recess to be freely fitted, and
It has a surface to be joined to the mating surface, and forms a pair with the concave portion of the boss.
A pair of holding members each having a circular concave portion are provided, and
In which both ends of the shaft are fitted into the recesses of the boss.
Put each holding member on each boss from the front side, and
Is located above and below the shaft and penetrates the holding member from the front
Screw the bolt onto the screw provided on the boss, and attach the holding member to the boss.
To the front fork
The front fork.
The length of the workpiece can be taken sufficiently and the degree of design freedom increases
This has the effect. In addition, with the above-described configuration,
Tool shaft above the lower end of the front fork.
Even if it is held, the ground contact between the inner cylinder and the outer cylinder
No force increases, front fork operability
Has the effect of not falling. In addition,
With the wheel shaft attached
Since the wheels can be attached and detached from the front, replacement work of the front wheels
Work can be done easily and in a short time
This has an effect, which is particularly suitable for a race or the like.
Furthermore, the boss supporting the wheel shaft is
Provided on the inside parts of the front fork facing each other
Therefore, the distance between the load support points can be further reduced.
And the boss is integrated with the outer wall of the front fork
Because it is formed, the rigidity can be increased.
Play a fruit. In addition, a boss that supports the wheel shaft
On the inner parts of the front fork facing each other
By fitting the two ends of the wheel shaft
The length of the part can be extended in the axial direction of the wheel shaft
So that the support area for the load is sufficient
It is possible to ensure, as a result, the wheel shaft
So that it can be firmly supported by the front fork
It has the effect of becoming. Further, according to the configuration described above,
The wheel shaft can be made shorter and lighter,
As the unsprung load becomes smaller, the cushioning performance is improved.
This has the effect. In addition, the boss and holding member
Does not protrude from the front or lower edge of the
This has the effect of making it difficult to contact with. Also,
The shaft is supported by joining the boss and the holding member
The structure is simplified as described above.
Play a fruit.

[Brief description of the drawings]

FIG. 1 is a partially cut-away schematic side view showing a main part of a motorcycle using one embodiment of a front wheel support device of the present invention.

FIG. 2 is a partially broken schematic front view showing details of a coupling portion between a front fork and a wheel shaft.

FIG. 3 is a sectional view showing details of a boss of a front fork.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motorcycle 2 Head pipe 3 Foot ton 4 Under bracket 5 Upper bracket 6 Front wheel 7 Inner cylinder 7a Support pipe 7b Sliding pipe 7c Metal ring 8 Outer cylinder 8a Metal ring 8b Oil seal 8c Dust seal 9 Cylinder 9a Bolt 10 Oil chamber 11 Protection Cover 12 wheel shaft 13 boss 13a recess 14 retaining member 15 bolt 16 ball bearing 17 wheel 18 tire 19 circlip 20 dust seal 21 positioning collar 22 circlip

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-178237 (JP, A) JP-A-61-92981 (JP, A) Jpn. 23612 (JP, Y1) Practical application Microfilm (JP, U) that photographs the contents of the specification and drawings attached to the application of Japanese Patent Application No. Hei 2-18818 (Japanese Utility Model Application No. 3-110991) (58) Int.Cl. ⁷ , DB name) B62K 25/02

Claims (1)

(57) [Claims] An inner cylinder is slidably fitted to a pair of left and right outer cylinders.
Wheel shaft at the bottom of the front fork
In the front wheel support device of the motorcycle that is held,
Left and right sides protruding from the outer wall of each front fork
A pair of bosses are integrally formed, and the front of each boss is
Forming a vertically long mating surface facing forward on the center axis
The center of the mating surface in the vertical direction
A semi-circular recess for detachably fitting the end from the front side
A surface formed and joined to the mating surface of the boss,
And a pair of holding members formed with a pair of semicircular concave portions
Are provided, and both end portions of the wheel shaft are fitted into the concave portions of the boss portion.
Cover each boss from the front side,
It is located above and below the wheel shaft and penetrates the holding member from the front
Screw to the screw provided on the boss, and
By connecting to the boss, the wheel shaft is
A motorcycle characterized by being supported by an oak
Car front wheel support device .