Title: Vibration-proofing structure for hollow pipe for vehicle
Abstract: To make it possible to fit a vibration-proofing member into a hollow pipe, without impairing the appearance and without increasing the number of component parts. A hollow pipe formed by extrusion of a light alloy is integrally provided on an inside surface thereof with a rib extending along the longitudinal direction of the hollow pipe. A vibration-proofing member for restraining vibration of the hollow pipe is inserted in the hollow pipe so that the rib holds a position thereof in the hollow pipe in a direction orthogonal to the longitudinal direction.
Patent Number: 6,845,842 Issued on 01/25/2005 to Yamamoto, et al.
| Inventors:
|
Yamamoto; Kazuo (Saitama, JP);
Matsubayashi; Mikimasa (Saitama, JP)
|
| Assignee:
|
Honda Giken Kogyo Kabushiki Kaisha (Tokyo, JP)
|
| Appl. No.:
|
302925 |
| Filed:
|
November 25, 2002 |
Foreign Application Priority Data
| Nov 30, 2001[JP] | 2001-365558 |
| Current U.S. Class: |
181/209; 181/207; 181/208 |
| Intern'l Class: |
F16F 015/00 |
| Field of Search: |
181/209,207,208
|
References Cited [Referenced By]
| Foreign Patent Documents |
| 07034895 | Jul., 1993 | JP.
| |
| 2594734 | Dec., 1996 | JP.
| |
| 10166825 | Jun., 1998 | JP.
| |
Primary Examiner: Hsieh; Shih-yung
Attorney, Agent or Firm: Birch, Stewart, Kolasch & Birch, LLP
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This nonprovisional application claims priority under 35 U.S.C. .sctn.
119(a) on Patent Application No. 2001-365558, filed in Japan on Nov. 30,
2001. The entirety of which is hereby incorporated by reference.
Claims
What is claimed is:
1. A vibration-proofing structure for a hollow pipe for a vehicle,
comprising:
a hollow pipe for a vehicle, said hollow pipe being formed by extrusion of
a light alloy and being integrally provided on an inside surface thereof
with a rib extending along a longitudinal direction of said hollow pipe;
and
a vibration-proofing member for restraining vibration of said hollow pipe,
said vibration-proofing member being inserted in said hollow pine so that
a position of said vibration-proofing member in said hollow pipe in a
direction orthogonal to the longitudinal direction is held by said rib,
wherein said vibration-proofing member is provided with a plurality of
engaging portions for engagement with said rib at intervals along the
longitudinal direction of said rib.
2. The vibration-proofing structure for a hollow pipe for a vehicle
according to claim 1, wherein said vibration-proofing member is formed of
an elastic material and is provided with a groove for elastic engagement
with said rib.
3. The vibration-proofing structure for a hollow pipe for a vehicle
according to claim 1, wherein said hollow pipe forms at least a part of a
rear fork of a motorcycle.
4. The vibration-proofing structure for a hollow pipe for a vehicle
according to claim 1, wherein said hollow pipe forms at least a part of a
main frame of a motorcycle.
5. A vibration-proofing structure for a hollow pipe for a vehicle,
comprising:
a hollow pipe for a vehicle, said hollow pipe being formed by extrusion of
a light alloy and being integrally provided on an inside surface thereof
with a rib extending along a longitudinal direction of said hollow pipe;
and
a vibration-proofing member for restraining vibration of said hollow pipe,
said vibration-proofing member being inserted in said hollow pipe so that
a position of said vibration-proofing member in said hollow pipe in a
direction orthogonal to the longitudinal direction is held by said rib,
wherein said hollow pipe forms at least a part of a rear fork of a
motorcycle.
6. The vibration-proofing structure for a hollow pipe for a vehicle
according to claim 5, wherein said vibration-proofing member is formed of
an elastic material and is provided with a groove for elastic engagement
with said rib.
7. A vibration-proofing structure for a hollow pipe for a vehicle,
comprising:
a hollow pipe for a vehicle, said hollow pipe being formed by extrusion of
a light alloy and being integrally provided on an inside surface thereof
with a rib extending along a longitudinal direction of said hollow pipe:
and
a vibration-proofing member for restraining vibration of said hollow pipe,
said vibration-proofing member being inserted in said hollow pipe so that
a position of said vibration-proofing member in said hollow pipe in a
direction orthogonal to the longitudinal direction is held by said rib,
wherein said hollow pipe forms at least a part of a main frame of a
motorcycle.
8. The vibration-proofing structure for a hollow pipe for a vehicle
according to claim 7, wherein said vibration-proofing member is formed of
an elastic material and is provided with a groove for elastic engagement
with said rib.
9. A motorcycle, comprising:
a main frame, said main frame including a main frame front portion and a
main frame rear portion;
a front fork, said front fork being rotatably supported by said main frame
front portion and supporting a front wheel;
a rear fork, said rear fork being vertically swingably supported by said
main frame rear portion and supporting a rear wheel; and
a vibration-proofing member, said vibration-proofing member forming at
least a part of at least one of said main frame and said rear fork and
comprising:
a hollow pipe, said hollow pipe being formed by extrusion of a light alloy
and being integrally provided on an inside surface thereof with a rib
extending along a longitudinal direction of said hollow pipe; and
a vibration-proofing member for restraining vibration of said hollow pipe,
said vibration-proofing member being inserted in said hollow pipe so that
a position of said vibration-proofing member in said hollow pipe in a
direction orthogonal to the longitudinal direction is held by said rib.
10. The motorcycle according to claim 9, wherein said vibration-proofing
member is formed of an elastic material and is provided with a groove for
elastic engagement with said rib.
11. The motorcycle according to claim 10, wherein said vibration-proofing
member is provided with a plurality of engaging portions for engagement
with said rib at intervals along the longitudinal direction of said rib.
12. The motorcycle according to claim 10, wherein said hollow pipe forms at
least a part of said rear fork.
13. The motorcycle according to claim 10, wherein said hollow pipe forms at
least a part of said main frame.
14. The motorcycle according to claim 9, wherein said vibration-proofing
member is provided with a plurality of engaging portions for engagement
with said rib at intervals along the longitudinal direction of said rib.
15. The motorcycle according to claim 14, wherein said hollow pipe forms at
least a part of said rear fork.
16. The motorcycle according to claim 14, wherein said hollow pipe forms at
least a part of said main frame.
17. The motorcycle according to claim 9, wherein said hollow pipe forms at
least a part of said rear fork.
18. The motorcycle according to claim 9, wherein said hollow pipe forms at
least a part of said main frame.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a vibration-proofing structure for a
hollow pipe for a vehicle, which is preferably used for a frame member of
a vehicle such as a motorcycle. In particular, the present invention
relates to an improvement in a vibration-proofing structure for a hollow
pipe for a vehicle in which a vibration-proofing member is fitted.
2. Description of Background Art
Japanese Patent No. 2594734 has disclosed a structure in which a
vibration-proofing member formed of an elastic material is fitted to the
outside or the inside of a hollow pipe. The vibration-proofing member is
constituted by connecting a pair of split members between a holding plate
fastened to the hollow pipe and the hollow pipe.
According to the above-mentioned conventional structure; however, the
appearance of the hollow pipe may be impaired when the vibration-proofing
member is fitted to the outside of the hollow pipe. Furthermore, even when
the vibration-proofing member is fitted to the inside or the outside of
the hollow pipe, other component parts such as the holding plate and screw
members are required in addition to the vibration-proofing member. This
leads to an increase in the number of component parts.
SUMMARY OF THE INVENTION
The present invention has been made in consideration of the above-mentioned
circumstances. Accordingly, it is an object of the present invention to
provide a vibration-proofing structure for a hollow pipe for a vehicle in
which a vibration-proofing member can be fitted to a hollow pipe while
preventing the appearance from being impaired and while obviating an
increase in the number of component parts.
In order to attain the above object, according to a first aspect of the
present invention, a hollow pipe for vehicle is formed by extrusion of a
light alloy. The hollow pipe is integrally provided on an inside surface
thereof with a rib extending along a longitudinal direction of the hollow
pipe. A vibration-proofing member is included for restraining vibration of
the hollow pipe. The vibration-proofing member is inserted in the hollow
pipe so that the rib holds a position in the hollow pipe in a direction
orthogonal to the longitudinal direction.
According to such a construction, the appearance of the hollow pipe is not
impaired because the vibration-proofing member is inserted in the hollow
pipe. Furthermore, the number of component parts is not increased because
the vibration-proofing member is held in the hollow pipe by the rib, which
is integral with the hollow pipe. In addition, the rib extends in the
longitudinal direction of the hollow pipe, which is formed by extrusion of
a light alloy. Accordingly, the rib can be formed simultaneously with the
extrusion of the hollow pipe. Furthermore, the rib does not act as an
obstacle at the time of inserting the vibration-proofing member into the
hollow pipe.
In addition, according to a second aspect of the present invention, the
vibration-proofing member is formed of an elastic material and is provided
with a groove for elastic engagement with the rib. According to such a
construction, the vibration-proofing member can be held in the hollow pipe
more securely while maintaining the position of the vibration-proofing
member in the longitudinal direction of the hollow pipe by a frictional
force arising from the elastic engagement of the groove with the rib.
According to a third aspect of the present invention, the
vibration-proofing member is provided with a plurality of engaging
portions for engagement with the rib at intervals along the longitudinal
direction of the rib. According to such a construction, a plurality of
portions spaced along the longitudinal direction of the vibration-proofing
member make sliding contact with the hollow pipe at the time of inserting
the vibration-proofing member into the hollow pipe. Accordingly, the
frictional resistance at the time of inserting the vibration-proofing
member can be suppressed to a comparatively low value. Therefore, the
inserting operation can be facilitated.
According to a fourth aspect of the present invention, at least a part of a
rear fork of a motorcycle is constructed of the hollow pipe. According to
such a construction, the effect of any of the first through third aspects
of the present invention can be obtained by constructing a
vibration-proofing structure for the rear fork.
Furthermore, according to a fifth aspect of the present invention, at least
a part of a main frame of a motorcycle is constructed of the hollow pipe.
According to such a construction, the effect of any of the first through
third aspects of the present invention can be obtained by constructing the
vibration-proofing structure for the main frame.
Further scope of applicability of the present invention will become
apparent from the detailed description given hereinafter. However, it
should be understood that the detailed description and specific examples,
while indicating preferred embodiments of the invention, are given by way
of illustration only, since various changes and modifications within the
spirit and scope of the invention will become apparent to those skilled in
the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed
description given hereinbelow and the accompanying drawings which are
given by way of illustration only, and thus are not limitative of the
present invention, and wherein:
FIG. 1 is a side view of a motorcycle to which the present invention has
been applied;
FIG. 2 is a perspective view of a body frame;
FIG. 3 is a perspective view of a rear fork;
FIG. 4 is a plan view of the rear fork;
FIG. 5 is a sectional view taken along line 5--5 of FIG. 4;
FIG. 6 is an enlarged view taken along line 6--6 of FIG. 5;
FIG. 7 is a sectional view taken along line 7--7 of FIG. 6; and
FIG. 8 is a sectional view taken along line 8--8 of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described with reference to the
accompanying drawings.
FIGS. 1 to 8 show one embodiment of the present invention. Referring to
FIG. 1, the motorcycle includes a front fork 11 for supporting a front
wheel WF. A body frame 13 includes a head pipe 12 at a front end thereof
for steerably supporting the front fork 11. A rear fork 15 is vertically
swingably supported on a rear portion of the body frame 13 through a
pivotal shaft 14. The rear fork 15 supports a rear wheel WR. Furthermore,
a seat stay 17 extends rearwardly upward from an intermediate portion of
the body frame 13. The seat stay 17 supports a seat 16. A fuel tank 18 is
mounted on the body frame 13 and a front portion of the seat stay 17.
Furthermore, an engine (not shown) is disposed on a lower side of the fuel
tank 18 and a cowling 19 covers the engine and the body frame 13. The
engine and the cowling 19 are fitted to the body frame 13.
As shown in FIG. 2, the body frame 13 includes the head pipe 12. A
left-right pair of main frames 21 is connected to the head pipe 12 through
a gusset stay 20. The left-right pair of main frames 21 extends rearwardly
downward. Furthermore, a cross member 22 connects the rear ends of the
main frames 21.
The main frame 21 has a structure in which a main frame front portion 23
and a main frame rear portion 24 are connected by welding through a hollow
pipe 25. The main frame front portion 23 includes the head pipe 12
integrally formed by die-casting. The main frame rear portion 24 includes
the cross member 22 integrally formed by die-casting. The hollow pipe 25
(the hatched portion) has a tubular form with a tetragonal cross-sectional
shape. Furthermore, the hollow pipe 25 is formed by extrusion of a light
alloy, for example, an aluminum alloy.
As shown in FIGS. 3 to 5, the rear fork 15 includes a left-right pair of
bearing cylinders 26 supported by the pivotal shaft 14. A left-right pair
of hollow pipes 27 is connected to the bearing cylinders 26 and extends
rearwards. Bearing members 28 are welded to the rear ends of the hollow
pipes 27 to close the rear ends of the hollow pipes 27. Furthermore, a
cross member 29 connects the portions of the hollow pipes 27 near the
bearing cylinders 26. In addition, the hollow pipes 27 are formed by
extrusion of a light alloy, for example, an aluminum alloy.
Referring also to FIGS. 6 and 8, a vibration-proofing member 30 for
restraining vibration of the hollow pipe 27, namely, of the rear fork 15
is inserted in the hollow pipe 27. Ribs 31 for holding the position of the
vibration-proofing member 30 in the hollow pipe 27 are integrally
projected on both inside surfaces of the hollow pipe 27. The ribs extend
along the longitudinal direction of the hollow pipe 27.
On the other hand, the vibration-proofing member 30 is formed of an elastic
material such as rubber, and is comprised of a polygonal columnar form
vibration-proofing member main portion 30a extending along the
longitudinal direction of the hollow pipe 27. The vibration-proofing
member 30 has a tetragonal cross-sectional shape. Furthermore, engaging
portions 30b integrally project in a plurality of locations from both side
surfaces of the vibration-proofing member main portion 30a. The engaging
portions 30b face toward both inside surfaces of the hollow pipe 27.
The engaging portions 30b are each roughly U-shaped while having a groove
32 for elastic engagement with the rib 31 at a central portion thereof.
Furthermore, the engaging portions 30b are integral with the
vibration-proofing member 30 at a plurality of locations spaced along the
longitudinal direction of the rib 31.
When the bearing member 28 is not connected to the rear end of the hollow
pipe 27, the vibration-proofing member 30 is inserted into the hollow pipe
27 to a predetermined position through a rear end opening portion of the
hollow pipe 27.
Depending on the insertion position of the vibration-proofing member 30
into the hollow pipe 27, a through-hole 33 as shown in FIGS. 6 and 8 may
be provided in a side wall of the hollow pipe 27 at a position
corresponding to an intermediate portion of the rib 31. In that case, in
order to prevent the through-hole 33 from being closed with the rib 31 and
the vibration-proofing member 30, a cutout portion 34 corresponding to the
through-hole 33 may be provided at an intermediate portion of the rib 31.
Furthermore, the vibration-proofing member 30 may be provided with a
cutout portion 35 formed by cutting off a part of the engaging portions
30b.
By the fitting of such a vibration-proofing member 30 to the hollow pipe
27, the high resonance frequency peculiar to the aluminum alloy
constituting the hollow pipe 27 can be suppressed. Therefore, vibration of
the rear fork 15 attendant on oscillation from the engine and the front
and rear wheels WF and WR can be restrained, thereby contributing to a
reduction in vibration noise.
In addition, the inside of the hollow pipe 25 (See FIG. 2) constituting a
part of the main frame 21 is also constructed in the same manner as the
inside of the hollow pipe 27 of the rear fork 15. Accordingly, vibration
of the main frame 21 attendant on oscillation from the engine and the
front and rear wheels WF and WR can be restrained, thereby contributing to
a reduction in vibration noise.
The operation of this embodiment will now be described. The hollow pipe 27
constituting at least a part (in this embodiment, a part) of the rear fork
15 is formed by extrusion of a light alloy such as an aluminum alloy. The
vibration-proofing member 30 for restraining vibration of the hollow pipe
27 is inserted in the hollow pipe 27, so that the appearance of the hollow
pipe 27 and hence the rear fork 15 is not impaired.
In addition, the hollow pipe 27 is integrally provided on it's inside
surface with the ribs 31 extending along the longitudinal direction of the
hollow pipe 27. The ribs 31 hold the position of the vibration-proofing
member 30 in the hollow pipe 27 in the direction orthogonal to the
longitudinal direction. Therefore, component parts other than the hollow
pipe 27 are not necessary in fitting the vibration-proofing member 30 into
the hollow pipe 27. Accordingly, the number of component parts is not
increased.
Moreover, the rib 31 extends in the longitudinal direction of the hollow
pipe 27, which is formed by extrusion of a light alloy. Therefore, the rib
31 can be formed simultaneously with the extrusion of the hollow pipe 27.
Furthermore, the rib 31 will not act as an obstacle at the time of
insertion of the vibration-proofing member 30 into the hollow pipe 27.
In addition, the vibration-proofing member 30 is formed of an elastic
material such as rubber, and the vibration-proofing member 30 is provided
with the groove 32 for elastic engagement with the rib 31. Therefore, the
vibration-proofing member 30 can be held in the hollow pipe 27 more
securely while maintaining the position of the vibration-proofing member
30 in the direction along the longitudinal direction of the hollow pipe 27
by a frictional force arising from the elastic engagement of the groove 32
with the rib 31.
Furthermore, the vibration-proofing member 30 is provided with the
plurality of engaging portions 30b for engagement with the rib 31 at
intervals along the longitudinal direction of the rib 31. At the time of
insertion of the vibration-proofing member 30 into the hollow pipe 27, a
plurality of portions of the vibration-proofing member 30 spaced along the
longitudinal direction make sliding contact with the hollow pipe 27.
Accordingly, the frictional resistance at the time of inserting the
vibration-proofing member 30 can be suppressed to be comparatively low,
and the inserting operation can be facilitated.
In addition, at least a part of the main frame 21 is constituted of the
hollow pipe 25. Furthermore, the vibration-proofing member 30 is inserted
into and held in the hollow pipe 25, with the same structure as in the
hollow pipe 27 of the rear fork 15. Therefore, the same effects as those
in the hollow pipe 27 of the rear fork 15 can be accomplished in the
hollow pipe 25 of the main frame 21.
As described above, according to the first aspect of the present invention,
fitting of the vibration-proofing member can be performed without
impairing the appearance of the hollow pipe and without increasing the
number of component parts. In addition, the rib can be formed
simultaneously with the extrusion of the hollow pipe. Accordingly, the rib
does not act as an obstacle at the time of inserting the
vibration-proofing member into the hollow pipe.
In addition, according to the second aspect of the present invention, the
vibration-proofing member can be held in the hollow pipe more securely
while maintaining the position of the vibration-proofing member in the
direction along the longitudinal direction of the hollow pipe by a
frictional force arising from the elastic engagement of the groove with
the rib.
According to the third aspect of the present invention, the frictional
resistance at the time of inserting the vibration-proofing member can be
suppressed to be comparatively low. Furthermore, the inserting operation
can be facilitated.
According to the fourth and fifth aspects of the present invention, the
effect of any of the first through third aspects of the present invention
can be accomplished by constructing the vibration-proofing structure for
the rear fork or the main frame, respectively.
The invention being thus described, it will be obvious that the same may be
varied in many ways. Such variations are not to be regarded as a departure
from the spirit and scope of the invention, and all such modifications as
would be obvious to one skilled in the art are intended to be included
within the scope of the following claims.
*
