U.S. patent application number 09/785171 was filed with the patent office on 2001-06-28 for bicycle rim for a tension spoke bicycle wheel.
This patent application is currently assigned to MAVIC S.A., Saint Trivier sur Moignans, FRANCE. Invention is credited to Mercat, Jean-Pierre, Minville, Alban.
Application Number | 20010005099 09/785171 |
Document ID | / |
Family ID | 9494219 |
Filed Date | 2001-06-28 |
United States Patent
Application |
20010005099 |
Kind Code |
A1 |
Mercat, Jean-Pierre ; et
al. |
June 28, 2001 |
Bicycle rim for a tension spoke bicycle wheel
Abstract
The invention relates to a rim, spokes and a complete wheel,
especially a cycle wheel, including such a rim and such spokes. The
rim has a plurality of through holes demarcated by a chimney
obtained by backflow. A threaded insert is housed in these
openings. The end of the spoke includes a joining piece affixedly
connected to the end of the spoke, a tension adjusting screw
mounted to rotate freely on this side of the joining piece, and
extended by a coupling sleeve with a tightening tool. The joining
piece is provided to slide within the insert, and the screw is
tightened within the joining piece.
Inventors: |
Mercat, Jean-Pierre;
(Chaneins, FR) ; Minville, Alban; (Romaneche
Thorens, FR) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN
1941 ROLAND CLARKE PLACE
RESTON
VA
20191
|
Assignee: |
MAVIC S.A., Saint Trivier sur
Moignans, FRANCE
|
Family ID: |
9494219 |
Appl. No.: |
09/785171 |
Filed: |
February 20, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09785171 |
Feb 20, 2001 |
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08893761 |
Jul 11, 1997 |
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6224165 |
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Current U.S.
Class: |
301/95.102 ;
301/58 |
Current CPC
Class: |
B60B 21/025 20130101;
B60B 2900/311 20130101; B60B 21/064 20130101; B60B 21/062 20130101;
B60B 1/041 20130101; B60B 1/048 20130101 |
Class at
Publication: |
301/95 ;
301/58 |
International
Class: |
B60B 021/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 12, 1996 |
FR |
96 09047 |
Claims
What is claimed is:
1. A bicycle rim for a tension spoke bicycle wheel, said rim
comprising: a one-piece circular profiled member centered around an
axis of rotation, said profiled member having a cross-section
including a lower bridge arranged closer to the axis of rotation,
an upper bridge arranged radially outward of said lower bridge, and
a pair of lateral walls interconnecting said lower bridge and said
upper bridge and extending radially outwardly beyond said upper
bridge to form a pair of wing portions, said wing portions and said
upper bridge defining an annular channel for receiving a tire; and
at least one through hole in at least said lower bridge, said at
least one through hole being demarcated by a tubular backflow
chimney having a height greater than a thickness of said at least
lower bridge, and said backflow chimney extending from said lower
bridge toward said upper bridge.
2. A rim according to claim 1, wherein the chimney is threaded.
3. A rim according to claim 2, wherein only the lower bridge is
bored with said at least one through hole, and the upper bridge is
not bored.
4. A rim according to claim 2, wherein a threaded insert is
introduced in each of said at least one chimney.
5. A rim according to claim 4, wherein the insert is provided with
a polygonal section on at least one portion of its height.
6. A rim according to claim 1, wherein the chimney is threaded and
is oriented toward the interior of an area defined by said upper,
lower, and lateral walls.
7. A rim according to claim 1, wherein both said upper bridge and
said lower bridge include at least one said through hole.
8. A rim according to claim 7, wherein the chimneys of said upper
bridge and said lower bridge are aligned and extend toward one
another.
9. A rim according to claim 1, wherein said tubular backflow
chimney is formed by flow drilling.
10. A rim according to claim 1, wherein the chimney includes
internal threads extending therealong a distance greater than the
thickness of said lower bridge, thereby providing a greater
threaded length for engagement by threaded tension spokes than
would be provided by threading said lower bridge alone which
results in a greater holding ability.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 08/893,761, filed Jul. 11, 1997, in the names of Jean-Pierre
Mercat and Alban Minville, entitled "METHOD FOR BORING A SPOKE RIM,
RIM BORED ACCORDING TO THE METHOD, INSERT ADAPTED TO EQUIP THE RIM,
AND WHEEL ESPECIALLY CYCLE RIM", the entire disclosure of which is
expressly incorporated by reference herein in its entirety. The
present application is also related to commonly owned, copending
U.S. application Ser. No. 09/227,942, filed Mar. 29, 1999, in the
names of Jean-Pierre Mercat and Alban Minville, entitled "METHOD
FOR BORING A SPOKE RIM, RIM BORED ACCORDING TO THE METHOD, INSERT
ADAPTED TO EQUIP THE RIM, AND WHEEL ESPECIALLY CYCLE RIM", which is
a continuation-in-part of U.S. application Ser. No. 08/893,761
(noted above), filed Jul. 11, 1997, and which is also a
continuation-in-part of U.S. application Ser. No. 08/893,700, filed
Jul. 11, 1997, in the names of Jean-Pierre Mercat and Alban
Minville, entitled "METHOD FOR BORING A SPOKE RIM, RIM BORED
ACCORDING TO THE METHOD, INSERT ADAPTED TO EQUIP THE RIM, AND WHEEL
ESPECIALLY CYCLE WHEEL", now abandoned.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method for boring a wheel
spoke rim. The invention also relates to a rim obtained using the
method. The invention is also related to a spoke, a spoke nipple
provided to equip the rim obtained by the method, as well as a
wheel obtained by assembling the rim with such spokes and spoke
nipples.
[0004] 2. Background and Material Information
[0005] In a known manner, a wheel, especially a bicycle wheel,
includes a central hub connected to a circular rim by two rows of
spokes. The rim is formed of two circular bridges connected by two
lateral flanks so as to form a box. The lateral flanks are extended
outwardly by two wings, so as to form, with the upper bridge, an
annular channel provided to receive a tubular. For certain rims
that are provided to receive a tube, the channel is a mere groove
formed by a caving-in of the upper bridge. The spokes are connected
to the rim by nipples screwed at the end of the spokes. These
nipples further make it possible to adjust the tension of the
spokes.
[0006] To receive the spoke nipples in a conventional manner, the
two bridges of the rim are bored with openings spread along the
circumference of the rim. The openings of the lower bridge are
provided to serve as a seat for the nipple heads. The openings of
the upper bridge, with a greater diameter, are provided to enable
the positioning of the spoke nipple from the outside.
[0007] To improve the conditions in which the nipple head takes
support against the rim, and the distribution, in the rim, of the
stresses induced by the tension of the spokes, it is known to equip
the rims with eyelets that extend through the openings of the lower
bridge. These eyelets are assembled by crimping to the periphery of
the opening of the lower bridge. They further have a cup-shaped
eyelet body whose lower portion rests on the lower bridge, and the
upper portion has an edge that rests against the upper bridge. The
base of these eyelets is bored for the passage of the nipple body.
These eyelets are advantageous because they establish mechanical
linkages between the two bridges, which reinforces the structure of
the rim and its bending strength.
[0008] A monoblock eyelet is described in the patent application EP
130 449. These eyelets also exist in the form of two distinct
elements assembled at the level of the crimping.
[0009] However, for such rims, the openings of the bridges
constitute local weakening zones which weaken each of the two
bridges. In addition, these openings must have a relatively large
size. The openings of the lower bridge must indeed have a diameter
that is sufficient to allow for the passage of the nipple body and
its free rotation. The openings of the upper bridge must enable the
passage of the nipple head upon which the fastening of the spoke to
the rim, as well as the adjustment tools are dependent.
[0010] Another problem of these rims is that when adjusting the
tension of the spokes, the spoke itself is torsionally biased and
twists over itself before a relative movement occurs at the level
of the threads for linking with the nipple. As a result, the
tension adjustment of the spokes is relatively inaccurate, and the
spokes do not work properly.
[0011] Another problem of these rims comes from the manufacturing
of the eyelets. Indeed, if one wishes to equip the rim with
cup-shaped double eyelets, the distance between the two bridges of
the rim is directly related to the height of the cup of the eyelet.
Since the eyelet is conventionally made of stainless steel by
stamping, the maximum height of an eyelet is thereby limited, which
imposes dimensional constraints for the rim.
[0012] However, a rim having threaded openings is known from the
published Patent Application No. WO 93/09963. The threaded end of
the spokes is connected to this rim by means of a nipple that is
threaded internally and externally with a different pitch. This rim
further has an unpunched upper bridge, except for the mounting of a
valve, if necessary, which makes the rim airtight, and therefore
appropriate for the mounting of a tubeless type of tire.
[0013] However, the lower bridge that is bored and threaded must be
reinforced in its thickness to withstand the stresses, which
results in an undesired increase in the weight and inertia of the
rim. The mode for mounting the spokes does not solve the spoke
twisting problem either.
SUMMARY OF THE INVENTION
[0014] An object of the invention is to propose a method for boring
a rim which makes it possible to obtain a rim having improved
mechanical characteristics, without any significant weight
increase.
[0015] Another object of the invention is to propose a rim bored
with openings which has an improved resistance to fracture.
[0016] Another object of the invention is to propose a rim in which
the distance between the two bridges is freed from the height limit
constraint for the cups of the eyelets.
[0017] Another object of the invention is to propose a wheel
equipped with spokes whose tractional working conditions are
improved.
[0018] Other objects and advantages of the invention will become
apparent along the description that follows.
[0019] According to the invention, the method for making a rim
bored with openings provided to receive spokes for linkage with a
hub, the rim having a box with an upper bridge and a lower bridge,
includes the feature that at least the lower bridge is bored with a
through hole by means of flow drilling bit operating in the
direction of the upper bridge.
[0020] The rim obtained using the method includes the feature that
at least one of the bridges has a plurality of through holes
demarcated by a backflow chimney whose height is greater than the
thickness of the bridge.
[0021] The spoke provided to equip the preceding rim includes the
feature that it has a joining piece affixedly assembled to the end
of the spoke, and a tension adjusting screw mounted to rotate
freely and set back with respect to the joining piece.
[0022] The wheel according to the invention has a rim such as
aforementioned, a central hub and connecting spokes between the rim
and the hub.
[0023] According to another characteristic, the rim includes at
least one spoke such as aforementioned.
BRIEF DESCRIPTION OF DRAWINGS
[0024] The invention will be better understood along the following
description, with reference to the annexed drawings that are an
integral part thereof, and in which:
[0025] FIG. 1 a general side view of a wheel;
[0026] FIG. 2 is a front view of the wheel of FIG. 1;
[0027] FIG. 3 is a partial front and cross sectional view, through
a transverse plane of section, of a rim in the raw state;
[0028] FIG. 4 illustrates the operation of boring the rim according
to a first embodiment of the invention;
[0029] FIG. 5 shows the result of the boring operation;
[0030] FIG. 6 illustrates the following step of threading the
openings of the rim;
[0031] FIG. 7 shows a front and cross sectional view, through a
transverse plane, of an insert provided to be screwed in the
openings;
[0032] FIG. 8 is a top and cross sectional view of the insert of
FIG. 7;
[0033] FIG. 9 shows the insert mounted in the rim;
[0034] FIG. 10 is a side view of a spoke provided to be assembled
to the insert;
[0035] FIG. 11 is a view similar to FIG. 10 where the elements
located at the end of the spoke are shown in cross section;
[0036] FIG. 12 shows the spoke assembled to the rim;
[0037] FIG. 13 is a view similar to FIG. 12 and illustrates another
embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] FIG. 1 shows a bicycle wheel which includes a circular rim 2
connected to a central hub 3 by spokes 4. Only a portion of the
spokes is shown in this FIG. In a known manner, the hub has
appropriate means for providing the linkage with the frame. As is
visible in FIG. 2, the spokes are distributed along two symmetrical
rows, each of which is fastened to an end of the hub 3.
[0039] The wheel shown in FIGS. 1 and 2 is a front wheel. In the
case of a conventional rear wheel, one of the rows of spokes is
offset toward the median portion of the hub, such that the hub has,
on this side, a joining piece that includes the free wheel
mechanism and serves as a support for the sprocket box. This is
known to one with ordinary skills in the art.
[0040] FIG. 3, in a transverse cross section and partial view,
shows the rim 2 in the raw state. This rim has, in a known manner,
a box structure having a lower bridge 5 and an upper bridge 6
connected by lateral walls 7 and 8. These walls are extended beyond
the upper bridge 6 by two wings 9 and 10 which form, with the
bridge 6, an annular channel provided to receive a tire and a tube,
if necessary.
[0041] The rim shown in the FIG. is however not limiting for the
invention, neither with respect to the profile of the section, nor
with respect to the mounting of a tire. The invention indeed
applies to rims provided to be equipped with a tire as well as to
rims provided to be equipped with a tube or any other tire
tread.
[0042] In a known manner, the rim such as that shown in FIG. 3 is
obtained from a shaped bar made of aluminum alloy or of any other
light alloy, such bar being bent and then butt joined by means of a
sleeve or by welding. In the raw state, the two bridges are
unpunched continuous walls.
[0043] FIGS. 4 and 5 illustrate the operation of boring the rim.
This operation, in a known manner, consists of boring the two
bridges of the rim at regular intervals, in order to enable the
fastening of the spokes. It must be noted that the boring of the
openings takes into account the specific orientation of each spoke,
such orientation being determined by the general orientation of
each row, and by the number of spokes per row.
[0044] According to the invention, the rims are bored, not by means
of a conventional cutting drill, but by means of flow drilling
drill bit. The flow drilling technique is known in itself. The
drill bits used for such a boring have a generally cylindrical
shape, with a punch-shaped tip. The tip is formed with edges, which
gives it a general shape of pointed pyramid. Other tool shapes are
also suitable.
[0045] Two tools 10 and 11 are used in the present case to bore the
two bridges. They are coaxially mounted, and are driven in a
rotational and translational movement in the direction of the rim
by any appropriate means.
[0046] The flow drilling technique has the particularity of not
cutting the material, but rather of pushing it in the direction of
progression of the drill bit along a chimney. In the present case,
the chimneys are oriented toward the interior of the box of the
rim.
[0047] Flow drilling can create a burr on the side opposite the
chimney. This burr is trimmed off or shaped by the drilling tool
itself which has at least on trimming tooth for this purpose. The
burr can also be trimmed off or shaped by a proper machining
operation.
[0048] FIG. 5 shows the rim in transverse cross section at the
level of a pair of openings, after drilling and removal of the
drill bits. Each bridge 5, 6, has a through hole 13, 14 demarcated
by a chimney 15, 16, which extends toward the interior of the box.
In the embodiment shown, the two openings 13 and 14 have the same
diameter. This is not limiting, and as will be described
subsequently, they can have a different diameter.
[0049] For each chimney, the height of the wall, and its thickness
depend on the characteristics of the material of the rim, on the
initial thickness of the bridge, on the diameter of the drill bit,
and on drilling parameters, rotational speed, progression speed,
etc.
[0050] One was able to obtain the following results.
[0051] For a rim made of aluminum alloy 6106, a 1.5 mm bridge was
bored with a drill bit having a 5.5 mm diameter. The chimney
obtained had a useful length of about 5 mm, this length including
the thickness of the bridge.
[0052] It must be noted here that the boring of the openings using
the flow drilling technique is advantageous with respect to the
mechanical strength of the rim. Indeed, the structure of the
material does no longer have any sudden discontinuity as is the
case for a conventional boring by cutting. Due to its peripheral
wall, the chimney maintains a certain homogeneity in the structure
of the bridges, such that the mechanical resistance to fracture of
the rim thus bored is higher than that of a rim bored in a
conventional manner.
[0053] Another advantage is that such a flow drilling does not
generate any chips; in particular, there is no chip that could
penetrate into the box.
[0054] Finally, the two chimneys are oriented toward the interior
of the box; therefore, there is no portion projecting outwardly,
especially on the side provided for the tire or the tube.
[0055] FIG. 6 illustrates the next manufacturing step which consist
of threading the two openings 13 and 14 of the bridges. After
threading, it is provided to screw a monoblock insert in the two
openings, such that the two threads are made as a function of one
another. If the two holes have the same diameter, the two threading
operations can be carried out with a single tap in a single pass.
If the openings have different diameters, a staged tap, or any
other appropriate means, can be used.
[0056] The insert 18 provided to be screwed in the two threaded
openings is shown in FIGS. 7 and 8. It has the shape of a tube
portion that is threaded at its outer wall with respect to the
diameter and pitch of the openings 13 and 14. Preferably, the
length of the insert is equal to, or slightly less than the
distance between the upper surface of the upper bridge 6 and the
lower surface of the lower bridge 5, such that once screwed in the
two openings of the bridges, the insert is totally integrated
within the perimeter of a section of the rim.
[0057] The interior of the insert is also threaded to a pitch that
is independent of the external pitch of the insert. In addition,
the interior of the insert has, at least in its lower portion, a
polygonal section, for example hexagonal, that is obtained in the
thickness of the threading. Initially, this hexagonal section makes
it possible to screw the insert in the openings 13 and 14 by means,
for example, of an appropriate hexagonal wrench. As will appear
hereinafter, the hexagonal shape also serves as an anti-rotation
guide for a joining piece located at the end of the spoke. FIG. 8
shows the insert 18 in a top view, with its body 19, on the
exterior of the body, a thread 20 of the external threading, and on
the interior of the body, an internal thread 21 sectioned by six
triangular grooves 22 that are distributed at the peaks of a
hexagon, and together define a hexagonal section.
[0058] Other means can also be suited to ensure the coupling with a
tool in order to carry out the screwing of the insert, for example,
one or more grooves provided in the inner wall of the insert along
all or part of its height, and provided to cooperate with a tool
carrying one or more lugs arranged appropriately.
[0059] Likewise, the insert could have on the side of the lower
bridge, i.e., toward the interior of the rim, a projecting
extension, with a hexagonal external section, for example, which
enables the coupling of a screwing tool. This replaces the
hexagonal section within the insert. This internal hexagonal
section is however preferred, because it enables a weight gain on
the inserts, as well as a saving in space, and it facilitates the
spoke positioning which will be described in detail
subsequently.
[0060] The insert is made of any appropriate material, such as
aluminum alloy, for example.
[0061] The insert is provided to be screwed in the openings 13 and
14 of the rim, and preferably immobilized by any appropriate means,
such as adhesion, for example. FIG. 9 illustrates this step of
making the rim equipped with inserts.
[0062] Advantageously, the insert 18 provides a mechanical linkage
between the two bridges 5 and 6, which operates both ways in a
longitudinal direction defined by the insert. That is, contrary to
the eyelets that are crimped on one of the bridges and in mere
support on the other, the inserts here are embedded in each of the
bridges, and they connect the bridges affixedly. The risk of the
box collapsing is considerably reduced. The structure of the rim is
stiffened by such linkages. It was already stiffened by the
backflow chimneys. In addition, the flow drilling makes it possible
to have, at the level of each bridge, a threading height that is
much greater than the initial thickness of the wall of the bridge.
In other words, a screwing linkage can be used here without
significantly increasing the thickness of the wall. Furthermore,
the length of the insert is not limited by manufacturing
constraints, such that the distance which separates the two bridges
of the rim is selected without any constraint relative to the
length of the insert. The shape of the lower bridge can also be
selectively more streamlined, for example, because the insert is no
longer crimped but screwed within the rim.
[0063] A spoke provided to be fastened to the rim by screwing in
the insert is shown in FIGS. 10 and 11.
[0064] The spoke 25 shown is a wire with a bent head 26 that is
provided to be hooked to a lateral flange of a hub, by force
fitting in one of the openings of the flange. Of course, this is
not limiting, and the spoke could also have a strait head, i.e.,
with no bend, and could be assembled by any technique other than
force fitting, for example, by a mere engagement of the head in a
buttonhole-shaped housing, or in a cutout. The median portion of
the spoke has any section, in particular, it can be cylindrical or
have an aerodynamic profile. The spokes could also be replaced by
sticks assembled to the hub or integral therewith, the portion of
the spokes which will now be described constituting the end portion
of such sticks.
[0065] The spokes could also be formed from composite fibers.
[0066] This end portion includes a joining piece 28 that is affixed
to the end of the spoke by any appropriate means, for example,
screwing or adhesion on the threaded end of the spoke. The tip
could also be assembled by welding, by caulking the end of the
spoke, or it could be obtained by die forging the end of the same
spoke. According to the mode of assembling the head of the spoke to
the hub, especially by force fitting or by engagement into a slit,
the joining piece is assembled after or prior to the operation of
positioning the spoke on the hub.
[0067] The joining piece 28 has a polygonal section, for example
hexagonal, which corresponds to the internal section of the insert.
The joining piece is provided to engage and slide within the insert
18. The fact that the insert has an internal hexagonal section
facilitates the positioning of the spoke, even before its
tightening.
[0068] The cooperation between the hexagonal sections of the
joining piece of the spoke and of the insert has the effect of
retaining the end of the spoke in rotation, i.e., this prevents any
twisting of the spoke. As has been said previously regarding the
hexagonal section of the insert, any other appropriate means
performing this function is suited.
[0069] At the rear of the joining piece, the end of the spoke
carries a tension adjusting screw 30 which is traversed by the
spoke and is mounted to rotate freely at its end. The screw is
provided to abut against the joining piece 28 and to exert thereon
a thrust that induces a tension in the spoke by reaction. The screw
30 is also provided to be tightened within the insert 18, thereby
inducing a translation of the joining piece 28 within the
insert.
[0070] Preferably, as is shown in FIGS. 10 and 11, the tension
adjusting screw is extended on the side opposite the joining piece
by a coupling sleeve with the tightening tool, such a sleeve 31
having a hexagonal section, for example. Any other appropriate
means is also suitable.
[0071] FIG. 12 schematically shows the rim in a plane of section
including the insert.
[0072] This FIG. shows the various elements, in particular the
insert 18 engaged in the two openings of the bridges 5 and 6 of the
rim, the joining piece 28 slidably engaged in the insert, and the
tension adjusting screw 30 partially screwed in the insert, with
the coupling sleeve 31 accessible on the outside of the rim and
which makes it possible to adjust the tension of the spoke. It must
be noted that when adjusting the tension, the spoke only works in
stretching since the joining piece 28 prevents the end of the spoke
from pivoting. The spokes work in better conditions and the tension
adjustment is thereby more accurate.
[0073] The construction that has just been described can be carried
out with numerous variations. For the linkage between the rim and
the insert, it would be possible, for example, to use a drill bit
which provides the threading of at least one of the openings during
the same operation. One could also use self-threading inserts,
i.e., which create their own threading when they are screwed.
Another variation would consists of threading only one opening, for
example the opening of the lower bridge, and of ensuring the
linkage with the other bridge by means of a self-threading section
of the insert. According to another variation, the two openings
could be bored by a single oriented drill bit operating on the
upper bridge, and then on the lower bridge. Such a boring would
have the effect of orienting the chimney of the lower bridge toward
the outside of the box. According to another variation, the two
openings could have different diameters, the insert having in this
case a shoulder on which it can rest to ensure its tightening in
the openings. One could also use a blind insert on the side of the
upper bridge.
[0074] In this regard, FIG. 13 shows another embodiment of the
invention. According to this embodiment, only the lower bridge 35
of the rim 32 is bored according to the flow drilling technique, so
as to create a chimney 37. The upper bridge 36 is not bored, it
remains in the raw state. As is in the preceding case, an insert 38
is engaged by screwing in the chimney 37, and is tightened against
the upper bridge. The insert 38, as the insert 18, has an internal
wall threaded and machined along a hexagonal section.
[0075] The spoke 39 provided to cooperate with the insert 38 is
quite similar to the preceding spoke, having at its end a joining
piece 40 with a hexagonal section, a tension adjusting screw 41
extended by a coupling sleeve with a tightening tool.
[0076] Such a construction has the advantage that the rim is
impervious, i.e., on the side of the tire, it has a continuous
bridge that is unpunched, except for the mounting of the valve, if
necessary. Such a rim is appropriate for the mounting of a tubeless
type of tire, or a mounting where only a portion of the volume
defined by the tire is occupied by a tube or a filling material,
the other portion being occupied by pressurized air injected
between the rim and the tire.
[0077] This other embodiment of the invention can also have
alternatives of the same type as those that have been described
previously.
[0078] Although the invention has been described with reference to
particular means, materials, and embodiments, it is to be
understood that the invention is not limited to the particulars
expressly disclosed, but that the invention extends to all
equivalents within the scope of the claims that follow.
[0079] This application is based upon French Patent Application No.
96 09047, filed on Jul. 12, 1996, the disclosure of which is hereby
expressly incorporated by reference thereto in its entirety and the
priority of which is claimed under 35 USC 119.
* * * * *