U.S. patent application number 11/337342 was filed with the patent office on 2006-06-08 for molded running board.
This patent application is currently assigned to IPL, Inc.. Invention is credited to Philippe Begin, Michel Lanoue, Normand Mercier.
Application Number | 20060119065 11/337342 |
Document ID | / |
Family ID | 4169193 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060119065 |
Kind Code |
A1 |
Lanoue; Michel ; et
al. |
June 8, 2006 |
Molded running board
Abstract
A molded running board provided with a support portion and a top
portion is described herein. The support portion is made of plastic
material and provided with reinforcing ribs and the top portion is
made of a plastic material that is advantageously compatible with
the plastic material forming the support portion. A method for the
assembly of such a molded running board is also described herein.
This method includes the welding of a top portion to a support
portion via the use of a thin strand of plastic material compatible
with material used in the top portion and the support portion and
metallic particles in an electromagnetic press, for example.
Inventors: |
Lanoue; Michel; (Pintendre,
CA) ; Mercier; Normand; (Saint-Damien, CA) ;
Begin; Philippe; (Pintendre, CA) |
Correspondence
Address: |
EDWARDS & ANGELL, LLP
P.O. BOX 55874
BOSTON
MA
02205
US
|
Assignee: |
IPL, Inc.
St-Damien
CA
G0R 2Y0
|
Family ID: |
4169193 |
Appl. No.: |
11/337342 |
Filed: |
January 23, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10163446 |
Jun 4, 2002 |
6997469 |
|
|
11337342 |
Jan 23, 2006 |
|
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Current U.S.
Class: |
280/163 |
Current CPC
Class: |
B60R 3/002 20130101 |
Class at
Publication: |
280/163 |
International
Class: |
B60R 3/00 20060101
B60R003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 4, 2001 |
CA |
2,349,517 |
Claims
1. A molded running board for a vehicle comprising: a molded
support portion; and a molded second portion, said molded second
portion being molded separately from said support portion; and
wherein said support portion and said second portion are welded
together.
2. The molded running board according to claim 1, wherein said
second portion is a top portion fixedly secured to said support
portion.
3. The molded running board according to claim 1, wherein said
second portion is secured to said support portion via
electromagnetic welding.
4. The molded running board according to claim 1, wherein said
first molded support portion is reinforced with a material selected
from the group consisting of glass fiber, talc nanoparticles and
mineral filler.
5. The molded running board according to claim 4, wherein said
first molded support portion includes polypropylene.
6. The molded running board according to claim 1, wherein said
molded second portion includes thermoplastic olefin (TPO).
7. The molded running board according to claim 2, wherein said
support portion comprises reinforcing.
8. The molded running board according to claim 7, wherein said
support portion includes lateral edges, and wherein a height of
said reinforcing ribs is slightly larger than that of said lateral
edges; whereby a pressure is applied to said top portion by said
reinforcing ribs.
9. The molded running board according to claim 1, wherein said
support portion is generally open.
10. The molded running board according to claim 1, wherein said
support portion is mountable to the vehicle by at least two
brackets.
11. The molded running board according to claim 10, wherein said at
least two brackets are integrally formed with said support
portion.
12. The molded running board according to claim 10, wherein said at
least two brackets are formed separately from said support portion
in a material selected from the group consisting of thermoplastic
material and metal.
13. The molded running board according to claim 12, wherein said at
least two brackets are mounted to said support portion by means
selected from the group consisting of mechanical fasteners and
electromagnetic welding.
14. The molded running board according to claim 10, wherein said at
least one bracket includes a stiffening matrix of ribs.
15. The molded running board according to claim 2, wherein said
second portion has a step surface provided with non-skid ribs.
16. The molded running board according to claim 1, wherein said
support portion is provided with apertures on a bottom portion
thereof.
17. The molded running board according to claim 2, wherein said
support portion has a generally U-shaped cross-section.
18. The molded running board according to claim 17, wherein said
second portion has a separate step pad mounted thereto
19. The molded running board according to claim 18, wherein said
step pad is made of thermoplastic olefin and includes mounting tabs
configured and sized to engage corresponding apertures of said
support portion.
20. The molded running board according to claim 3, wherein said
support portion includes edge portions provided with a rectangular
channel therein to receive thin strands of an electromagnetic
adhesive.
21. The molded running board according to claim 20, wherein said
second portion is further provided with edges so configured and
sized as to be received in said channel.
22. The molded running board according to claim 2, wherein said
support and second portions are so configured as to yield a
generally tubular running board, when assembled.
23. (canceled)
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. (canceled)
30. (canceled)
31. A molded running board for a vehicle comprising: a rigid
support portion molded in a first thermoplastic material; a second
portion molded in a second thermoplastic material; and an
electromagnetic adhesive material interposed between said support
portion and said second portion; wherein said electromagnetic
adhesive material fixedly secures said second portion to said
support portion via electromagnetic welding.
32. The molded running board according to claim 31, wherein said
second portion is a top portion.
33. The molded running board according to claim 31, wherein said
first thermoplastic material is reinforced with a material selected
from the group consisting of glass fiber, talc nanoparticles and
mineral fillers.
34. The molded running board according to claim 33, wherein said
first thermoplastic material includes polypropylene.
35. The molded running board according to claim 31, wherein said
second thermoplastic material includes thermoplastic olefin.
36. The molded running board according to claim 31, wherein a) said
support portion comprises reinforcing ribs running lengthwise
between opposite ends of said support portion; b) said support
portion includes lateral edges, and c) a height of said reinforcing
ribs is slightly larger than that of said lateral edges; whereby
said top portion engages both said lateral edges and said
reinforcing ribs.
Description
FIELD OF THE INVENTION
[0001] The present invention is concerned with molded running
boards. More specifically, the present invention relates to a
molding running board having a reinforced plastic molded support
portion, to which is fixedly mounted a top or step portion also
made of plastic material.
BACKGROUND OF THE INVENTION
[0002] Running boards are very well known in the art. They are
usually mounted to the frames or sill of small trucks such as
pick-up trucks and Sport Utility Vehicles (SUVs) or to other
vehicles to help the users to get in and out of the vehicle.
[0003] Conventionally, these running boards are made of metallic
material such as steel, which is finished by chrome plating for
example, or painted, both for aesthetic reasons and for protection
against a corrosive environment. A drawback of these conventional
steel running boards is that they are quite heavy and costly to
manufacture.
[0004] More recently, running boards having a structural support
portion made of coated steel but provided with a plastic top or
step portion have been introduced in the market. These bi-material
running boards are advantageous since they have a slightly reduced
weight compared to conventional running boards and provide a top or
step surface with good aesthetic tri-dimensional surface
properties.
[0005] A drawback of the bi-material running boards is that their
weight is still significant and the costs associated with the
manufacturing and coating of the structural support portion is
still relatively high.
[0006] Therefore, there is still a need for running boards that
mitigate the above-mentioned drawbacks.
OBJECTS OF THE INVENTION
[0007] An object of the present invention is therefore to provide
an improved running board comprising molded plactic.
SUMMARY OF THE INVENTION
[0008] More specifically, in accordance with an aspect of the
present invention, there is provided a molded running board for a
vehicle comprising:
[0009] a support portion made of a first moldable material; and
[0010] a second portion made of a second moldable material and
fixedly secured to said support portion via welding;
[0011] wherein said first moldable material has structural
characteristics that are sufficient to provide adequate rigidity to
said running board.
[0012] In accordance with another aspect of the present invention,
there is provided a generally tubular molded running board for a
vehicle comprising:
[0013] a first generally U-shaped portion made of a moldable
material and provided with lateral edges; and
[0014] a second generally U-shaped portion made of a moldable
material and provided with lateral edges;
[0015] wherein a) said moldable material has structural
characteristics that are sufficient to provide adequate rigidity to
said running board; b) said lateral edges of one of said first and
second U-shaped portions includes a channel; c) said lateral edges
of the other of said first and second U-shaped portions include a
projection corresponding to said channel; and d) said projection
engages in said channel via welding.
[0016] In accordance with a third aspect of the present invention,
there is provided a method for making a molded running board
comprising the acts of:
[0017] molding a support portion;
[0018] molding a top portion;
[0019] providing at least one piece of thin strand of a material
compatible with both the support portion and the top portion;
[0020] assembling the top portion to the support portion into an
assembly; and
[0021] welding the assembly under pressure.
[0022] In accordance with a fourth aspect of the present invention,
there is provided a molded running board for a vehicle
comprising:
[0023] a rigid support portion made of a first thermoplastic
material;
[0024] a second portion made of a second thermoplastic material;
and
[0025] an electromagnetic adhesive material interposed between said
support portion and said second portion; said adhesive fixedly
securing said second portion to said support portion via
electromagnetic welding.
[0026] Other objects, advantages and features of the present
invention will become more apparent upon reading of the following
non-restrictive description of preferred embodiments thereof, given
by way of example only with reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In the appended drawings:
[0028] FIG. 1 is an exploded view of a molded running board
according to an embodiment of the present invention;
[0029] FIG. 2 is a perspective bottom view of the molded running
board of FIG. 1;
[0030] FIG. 3 is a sectional view taken along line 3-3 of FIG.
1;
[0031] FIG. 4 is an exploded view of a molded running board
according to a second embodiment of the present invention;
[0032] FIG. 5 is a perspective bottom view of the molded running
board of FIG. 4;
[0033] FIG. 6 is a sectional view taken along line 6-6 of FIG.
4;
[0034] FIG. 7 is an exploded perspective view of a molded running
board according to a third embodiment of the present invention;
[0035] FIG. 8 is a perspective view of the support portion of the
running board of FIG. 7;
[0036] FIG. 9 is a sectional view taken along line 9-9 of FIG.
7;
[0037] FIG. 10 is an exploded view of a molded running board
according to a fourth embodiment of the present invention;
[0038] FIG. 11 is a sectional view taken along line 11-11 of FIG.
10; and
[0039] FIG. 12 is a flow chart of the different steps in the
production of a molded running board according to the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0040] Generally stated, the present invention is concerned with
the molding of a full size running board having a support portion
and a second portion, for example in the form of a top or step
portion, that is secured to the support portion. The support
portion is advantageously made of a moldable material having
structural characteristics that provide adequate rigidity such as,
for example, reinforced polypropylene (PP), i.e. polypropylene that
has been reinforced with glass fiber for instance, while the top
portion may be made of a moldable thermoplastic material such as
thermoplastic olefin (TPO).
[0041] The present invention is also related to a method for
producing a molded running board where the support portion and the
second portion are molded separately and then fixedly secured
together using, for example, an electromagnetic welding process.
Indeed, it has been found that some other known processes to form a
plastic material running board are inadequate. For example,
extrusion processes do not easily allow the manufacture of objects
having varying cross sections or objects that are not straight.
Other types of plastic welding such as vibration, ultrasonic, hot
plate, infrared, or laser plastic welding processes usually do not
yield adequately strong and aesthetic bonds. Furthermore, the
diameter of running boards is generally too large to allow gas
assisted molding.
[0042] Turning now more specifically to FIGS. 1 to 3 of the
appended drawings, a molded running board 10 according to a first
embodiment of the present invention will be described.
[0043] The molded running board 10 comprises a structural support
portion 12; a top portion 14; and thin strands of an
electromagnetic adhesive material 16 provided between the support
portion 12 and the top portion 14.
[0044] As can be seen from FIG. 1, the support portion 12 is
generally open and comprises reinforcing ribs 18 running lengthwise
and transverse (not shown), and front and rear ends 20, 22
respectively provided with reinforcing ribs 24 and 26.
[0045] Three brackets 28, 30 and 32 are provided to mount the
support portion 12 to a vehicle (not shown) for which the running
board 10 is intended.
[0046] As can be better seen from FIG. 2, the three brackets 28, 30
and 32 are integrally formed with the support portion 12. It is
however to be noted that the brackets 28, 30 and 32 could
alternatively be formed separately, out of plastic or metal, from
the support portion 12 and assembled thereto via fasteners or by an
electromagnetic welding method for instance, as will be described
hereinbelow.
[0047] The brackets 28, 30 and 32 include a matrix of ribs 34,
which provide stiffening to the brackets 28, 30 and 32 without
unduly increasing the weight thereof, and which does not negatively
affect the aesthetic properties of the running board 10.
[0048] Referring back to FIG. 1, it can be seen that the top
portion 14 is complementarily shaped as to be welded onto the
support portion 12 as will be described in detail hereinbelow.
[0049] It is to be noted that a top surface 36 of the top portion
14 is provided with friction producing or non-skid ribs 38.
[0050] The thin strands of material 16 are provided to fixedly
secure the top portion 14 to the support portion 12 as will be
described hereinbelow.
[0051] The reinforcing ribs 18-26 and 34 as well as the anti-skid
ribs 38 may be better seen in FIG. 3. It is apparent from the
Figure that the reinforcing ribs 18 optionally have a height
slightly larger than that of the edges 19 of the support portion
12. This height difference causes a tension to be applied to the
top portion 14 once assembled to the support portion 12 to thereby
decrease rattling issues.
[0052] Turning now to FIG. 12 of the appended drawings, the main
steps in the manufacture of a molded running board according to the
present invention will be described.
[0053] In a first step 40, a support portion is injection molded in
a conventional fashion. According to a specific embodiment of the
present invention, the support portion is made of reinforced
polypropylene i.e. polypropylene that has been reinforced with
glass fiber, talc nanoparticles or other mineral filler for
instance. It has been found that the glass reinforced polypropylene
made by A. Schulman under the name Polyfort FPP 1239H containing
about 30% glass fibers by weight is adequate to mold the support
portion.
[0054] In a further step 42, which can be carried out
simultaneously with step 40, a top portion is molded. Still
according to a specific embodiment of the present invention, the
top portion is made of TPO. Of course, other suitable materials
that can be welded to the support portion, i.e. that are compatible
with the material used therefor, could be used.
[0055] In step 44, the support portion 12 and the top portion 14
are optionally given time to shrink together. It has been found
that 24 hours are sufficient for the support portion and the top
portion to reach a stable size.
[0056] In step 46, at least one piece of thin strand or string of
material is provided. The thin strand or string is advantageously
made of a material compatible with both the support portion and the
top portion. For example, according to a specific embodiment of the
present invention, the thin strand or string of material is made of
electromagnetic adhesive comprising polypropylene and ferromagnetic
particles. U.S. Pat. No. 3,620,875 issued to Richard J. Guglielmo
on Nov. 16, 1971 describes such thin strand or string of
electromagnetic adhesive material and is hereby included by
reference in its entirety. Of course, other suitable materials that
are compatible with both the support portion and the top portion
could be used.
[0057] Step 48 consists in assembling the support portion, the thin
strands of material and the top portion into an assembly.
[0058] In step 50, this assembly is put into an electromagnetic
press (not shown) which includes a coil surrounding the assembly.
An electric generator supplies the coil with a current that causes
the metallic particles embedded in the thin strand of material to
heat up and melt the polypropylene forming the strand, thus welding
the top portion to the support portion. This electromagnetic
welding process is described in the above-mentioned U.S. Pat. No.
3,620,875.
[0059] The resulting welded running board is kept into the press
after the electric generator is shut down to allow sufficient time
for a liquefied portion of the running board to solidify (step
52).
[0060] Finally, in step 54, a completed molded running board is
removed from the electromagnetic press.
[0061] It is to be noted that the apertures of the bracket intended
to mount the finished running board to the vehicle could be
provided with metallic inserts.
[0062] Turning now to FIGS. 4 to 6, a molded running board 100
according to a second embodiment of the present invention will be
described.
[0063] Since the molded running board 100 is very similar to the
molded running board 10 illustrated in FIGS. 1 to 3, only the
differences therebetween will be discussed in detail
hereinbelow.
[0064] The molded running board 100 comprises a support portion
102, a top portion 104 and thin strands of material 106. These
three elements being substantially as described in relation to the
corresponding ones comprised in the molded running board 10
illustrated in FIGS. 1 to 3.
[0065] A major difference between the molded running board 100 and
the molded running boards 10 can be better seen in FIG. 5 and 6
where it is clearly shown that a bottom portion of the support
portion 102 includes apertures 108. These apertures 108 allow both
for a reduction in weight and cost of the support portion 102 and
for the drainage of liquid that could enter the molded running
board 100.
[0066] It is to be noted that the longitudinal ends 110 and 112 of
the running board 100 are narrower than the corresponding ends of
the running board 10 to further reduce the weight thereof.
[0067] The steps of manufacture of the running board 100 are very
similar to the steps of manufacture of the molded running board 10,
described hereinabove in relation to FIG. 10. It is believed that
those skilled in the art can easily apply the method of manufacture
of the molded running board 10 to manufacture the running board
100. Therefore, these steps will not be repeated herein.
[0068] Turning now to FIGS. 7 to 9 of the appended drawings, a
molded running board 200 according to a third embodiment of the
present invention will now be described.
[0069] As can be better seen from FIG. 9, the molded running board
200 comprises a generally U-shaped cross-section support portion
202, a corresponding, also generally U-shaped, top portion 204, a
string of material 206 and a step pad 208 that can be mounted onto
the top portion 204. Again, the support portion 202 comprises three
brackets 210, 212 and 214 (FIGS. 7 and 8) that allow the molded
running board 200 to be mounted to a vehicle (not shown).
[0070] The support portion 202 includes reinforcing ribs 216 and
edge portions 218 provided with a rectangular channel 220 therein.
As can be seen from FIG. 9, the string of material 206 is inserted
in the channel 220.
[0071] The top portion 204 includes a generally flat under-surface
222 configured and sized to contact and complementarily fit with
the free ends 216a and 216b of the reinforcing ribs 216. As
discussed hereinabove, the top portion 204 and the support portion
202 are optionally so designed that the free ends 216a and 216b of
the reinforcing ribs 216 will exert a pressure on the top portion
204, therefore strengthening the running boards 200 and minimizing
the rattling issues.
[0072] Edges 224 of the top portion 204 are configured and sized as
to enter the channel 220 of the support portion 202. Furthermore,
each edge 224 is provided with a projection 225 located on an
external surface thereof. The contact between these projections 225
and an internal surface of the channel 220 ensures that, in the
case where the plastic material that liquefies during the
electromagnetic welding process is to overflow, it overflows
towards the inside of the running board 200, leaving the external
surface of the running board 200 without unsightly marks or
beads.
[0073] It is to be noted that both the support portion 202 and the
top portion 204 are advantageously made of reinforced plastic
material such as for example polypropylene reinforced with glass
fibers, as described hereinabove. Alternatively, depending on the
specific requirements for the running board, the top portion 204
could be made of non-reinforced material such as, for example,
TPO.
[0074] It will be easily understood by one skilled in the art that
once the support portion 202 and the top portion 204 are welded
together using an electromagnetic welding process such as described
hereinabove and illustrated in FIG. 12, a strong tubular molded
running board 200 will be formed.
[0075] The step pad 208 is advantageously made of TPO and may be
mounted to the top portion 204 using tabs 226 and corresponding
apertures 228 or by any other suitable means. Alternatively,
friction ribs (not shown) could be made on the top surface of the
element 204 instead of using a step pad 208.
[0076] As will be easily understood by one skilled in the art, an
advantage of using such the thin strand or string of material 206
provided with metallic particles is that it is possible to weld
together even the internal contacting surfaces of the support
portion 202 and of the top portion 204 for example.
[0077] It is also to be noted that in that specific embodiment,
both the support portion 202 and the top portion 204 are structural
elements of the molded running board 200.
[0078] Turning now to FIGS. 10 and 11 of the appended drawings, a
molded running board 300 according to a fourth embodiment of the
present invention will be described.
[0079] Since the molded running board 300 is very similar to the
molded running board 200 described in relation to FIGS. 8 to 9,
only the differences therebetween will be discussed in detail
hereinbelow.
[0080] Like the molded running board 200, the molded running board
300 comprises a generally U-shaped cross-section support portion
302, a corresponding generally U-shaped top portion 304, a string
of material 306 and a step pad 308 that can be mounted onto the top
portion 304.
[0081] The support portion 302 includes reinforcing ribs 316 and
edge portions 318 provided with an indented profile forming a
groove 320 therein.
[0082] The top portion 304 includes a large generally flat surface
322, and edges 324 provided with a channel 325 and a projection 323
so configured and sized to correspond to the profile of edge
portions 318 of the support portion 302. The string of material 306
is inserted in the channel 325, as can be seen from FIG. 11.
[0083] Here again, a contact between the projection 323 and an
internal surface of the groove 320, combined with an indentation
327 of the edge portion 318, ensures that in the case when the
plastic material that liquefies during the electromagnetic welding
process is to overflow, it overflows towards the inside of the
running board 300.
[0084] The pressure exerted by the reinforcing ribs 316 is
distributed on the large generally flat surface 322 of the top
portion 204, therefore strengthening the running boards 300.
[0085] As can be seen from FIG. 11, the top portion also includes
two internal channels 317 in which the reinforcing ribs 316 are
positioned when the top portion is assembled to the support
portion. These channels 317 are interesting since they prevent
lateral movement of the ribs 316, thereby strengthening the
assembled running board.
[0086] A major difference between the running board 300 and the
running board 200 described hereinabove is that the support portion
302 does not include integrally formed brackets to allow the molded
running board 300 to be mounted to the vehicle. Instead, the
support portion 302 includes standard nuts 310 that are embedded in
the plastic material forming the support portion 302. These nuts
310 are used to mount the completed running board to conventional
or to custom made brackets (not shown). Of course, other types of
mechanical fasteners could be used.
[0087] The support portion 302 and the top portion 304 are
advantageously made of reinforced plastic material such as for
example polypropylene reinforced with glass fibers as described
hereinabove. They are welded together using an electromagnetic
welding process such as described hereinabove and illustrated in
FIG. 12 to yield a tube-like strong molded running board 300. It is
to be noted that both the support portion 302 and the top portion
304 are structural elements of the molded running board 300.
[0088] The step pad 308 is advantageously made of TPO and may be
mounted to the top portion 304 using tabs 326 and corresponding
apertures 328 or by any other suitable means. Alternatively,
anti-skid ribs could be formed onto the top portion 304.
[0089] One skilled in the art will understand that even though the
embodiments described hereinabove and illustrated in the appended
drawings always have the support portion provided below the top
portion, that the portion provided on top could be the support
portion and the second portion would be provided below the support
portion.
[0090] Obvious advantages of a molded running board according to
the present invention include: [0091] a significant reduction of
production costs, due to the fact that a limited number of parts
are comprised in the molded running board, which further simplifies
inventory management; [0092] a significant reduction of the weight,
due mainly to the choice of materials used; [0093] an enhanced
recyclability of parts of the molded running board; [0094] a range
of alternatives are provided, including painting the running board
or leaving it as is, or even molding it in a colored plastic;
[0095] an aesthetic surface finish is provided; and [0096] a range
of ways to customize reinforcing ribs of the support portion to
obtain the desired stiffness before the electromagnetic welding
process.
[0097] Although the present invention has been described
hereinabove by way of preferred embodiments thereof, it can be
modified, without departing from the spirit and nature of the
subject invention as defined in the appended claims.
* * * * *