Note: Descriptions are shown in the official language in which they were submitted.
WO 93/10925 PCrtAU92~00631
~ ' 2123~86
'~ 1
,
~; Title: "IMPROVEr) PANEL CI~INC~ING METHODS"
, .
BACKGROU~D OF TlEE INVENTION
<~ 1. Field of the Invention
.~ This invention relates to impro~ed panel
5 clinching methods. The term "clinching'l is also known
.~, as ~Ipress joining" or "integral fastening". ,,'----
2. Prior Art
Spot welding is the most colmnonly used
techni~ue f or j oining vehicle body components in the
automokive industries. As the strength of each spot
`', weld ca:nnot be guaranteecl, eg. due to the inclusion of
rubbish between the components, or poor weld
penetration, designers must i~crease the nu~er of welds
to ensure adequate j oint strength .
.~ 15 Spot welding has not ye~ been deve~ oped as an
accurate ,, reli~ble m~thod f or j oining galvanised steel
or aluminium components,
~ With galvanised steel, weldi~g a~tion destrr:ys
3~ the galvanising ~out the weld site, making it liable to
corrosion~
Aluminium has great potential in the
automobile f ield due to its liyht weight, but the lack
of a suitable spot weldi:ng method is one reason which
has minimised its applicat;io~.
One alternative to spot weldin~ is the u~e of
self-piercing ri~et~, and a method of, and apparlatus
for, the fastening of metal panels with self-piercing
~¦ rivets is disclosed i.n US Patent No 4,615,475
(Fuhrmeister~ (= Intern~tional Publication N~.nber
Wo 8~/04710).
~ A further alternative method is metal
¦ clinching, where two sheets of metal are deformed into a
lockiny engagement using a punch-and-die combinat.ion.
Examples of metal clinching methods are disclosed in:
3~ 1. DE 4009813 (Fraunhoffer-Ges Ford Ange);
WO~3/10925 PCT~AU92/00631
. .. ~
2'1238~J~
2. DE 1452820 (Philips Patentverwaltung
GmbH);
3. DE 3726392 ~Kuka Schweissanlage);
4. EP 330061 ~Eckold WO & Co GmbH);
. EP 215449 (Rapp E.);
6. GB 2244946 (Fairacre Limited~,J
7. GB 2123734 (BTM Corporation);
8. US 3919955 tDu Vernay); and
9. US 3875~9 (Ladouceur et al).
,t 10 While these methods enable met l sheets to be
joined together, they have relativel~ low shear and
`~ axial load strengths, and the joints do not have an
outer face substantially flush with the surrounding
.~ sheet metal (and are so not applicable in exposed areas,
~l 15 eg. wi~hln an engine compartment)~
~3~
It is an object of ~:he present invention to
prc: vide a panel clinching method where the shear
strengths of the clinching j oint: is increased .
~- 20 It is a preferred object to provide a method
where the axial load strength of the clinched joint is
increased.
It is a further preferred object to pro~ide a
method whPre the outer face of the joint may be
substantially flush with the surrounding sheet metal.
It is a still urther preferrad object to
provide a method where a~cillar~ components may be
supp~rted by or from the clinched joint~
It is a still ur~her preferred object to
provide a method where the clinched joint may be
capped" to constrain any stxe~s lines in the metal
panels in the region of the j oint .
Other preferred objects will become apparerlt
f rom the f ollowing description .
3 5 In ~ne aspect, the present invention resides
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~ 3
in a panel clinching method wherein:
a hollow rivet or full tubular slug is
driven or inserted into a clinched joint and at least
the inner end of the shank of the rivèt or slug is
outwardly-deformed within the joint.
The term "outw~rdly-deformed" shali-~e used to
include deformation of all or part of the shank or stem
of the rivet or slug in at least one direction latexal
(or transverse) to the longitudinal axis of the shank or
stem.
In a single stage method, the rivet or slug
lmay be inserted into the joint as the joint is formed,
the rivet or slug co-operating with the punch to deform
the panels into the supporting die. In a two-stage
process, the rivet or slug co operates with the metal
panels into the die, and a sleeve external to the punch
then deforms the rivet or slug within the jointO
The bore of the rivet or slug may be threaded,
serrated or otherwise profiled to engage and support an
anchor for, eg~ a wirin~ loom support, a trim cover
panel ~astener or the like. A plastic insert may be
fitted to the rivet or slug to provide ~ flush outer
face.
Preferably, the pa~els are pre-clamped to the
¦25 die before the punch drives the rivet or slug into the
panels to form the clinched joint; or before the
cli~ched joint is formed and the ri~et ox slug is then
Iinserted into the joint.
¦In a second aspect, the present invention
130 resides in a panel clinching method where a solid or
semi-tubular ~ivet or slug is driven or inserted into a
Iclinched joint and at least the inner e~d of the shanX
Iof the rivet or 51ug is outwardl~-deformed within the
¦ 3Oint.
In a single stage process, the rlvet or slug
WO93/10925 PCT/AU92~00631
is interposed between the punch and the outer panel (to
be joined) and the rivet or slug is used to deform the
`:: metal pane~s into the die as the clinched joint is
formed.
5In a two-staged process, a conventional
; button-type clinched joint is formed and tb~-~ the rivet
or slug is pxe~sed into the joint by the punch.
~fPreferably, the panels are pre-clamped to the
$ die before the clinched joi~t is formed.
lOIn a third aspect, the present inventisn
resides in a panel clinching method where a ring, or a
~. body or component having a tapered bore or recess, is
i supported by a die and at least one panel is deformed
' into the ring or the ~ore or recess to form a clinched
joint therewith.
Preferably, the panels are deformed behind the
. ring or into engagement with inwar~ly-divergent walls in
the recess.
In a fourth aspect, the method of the third
20 aspect is used in combination with the hollow rivet or
tubular slug of the first aspect, or the solid or semi-
tubular rivet sr slug of the second aspect.
In a. fifth aspect, the present inven~ion
resides in a clinched joint for panels formed by the
25 me~hod of any one o the first to fourth aspects.
While the invention is particularly suitable
3 for joining sheet metal panels, it is also suitable for
polymeric materials (eg. polyethylene, polyurethane,
polypropylene, nylon) where~one or more metal panels are
30 s~bstituted by panels of polymeric material. For
example, the methods are suitable for joinlng, eg. an
aluminium sheet to a polypropylene sheet, where the
polymeric sheet may ~e locally preheated (eg. by the
~ supporting die) to assist in the "flow" of the polymeric
:1 35 material as the joint is formed~ The rings or
~j
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components may also be formed of polymeric material and
be clinched to metal and~ox polymeric material sheets~
The shanks of the rivets or slugs may be
provided with external splines, grooves, teeth or other
protrusions or recesses to provide additiopal grip
between the rivets or slugs and the pa~ers in the
clinched joint.
'~ Adhesives can be applied, eg. to the shanks of
i the rivets or sluys to assist ~onding of the xivets or
slugs to the panels. Adhesives may also be provided
within the bore of the tubular or semi-tubular rive~s or
slu~s to be extruded into the clinched joint, as the
rivets or slugs are deformed, to assist the bonding of
the rivets or slugs to the panels.
15BRIEF DESCRIPTION OF THE DRAWINGS
FIG 1 is a sectional side view of a hollow
rivet or tubular slug suitable for clinching two p nels
of metal together;
FIGS 2 to 5 are sectional side views of the
steps in a two-stage process of forming a clinched joint
of a first emhodLment;
FIG 6 is a sectional side view of the clinched
joint of the first embodLment;
FIG 7 is a sectional side view of a modif.ied
~ubular rivet or slug;
FIGS 8 to 11 are sectional side views of the
steps in a single-stage process of fo ~ ng a clinched
joint of ~ second embod~ment;
FIG 12 is a sectional side view of thP
clinched joint of the second embodiment;
FIG 13 is a sectional side view of a solid
rivek or slu~;
FIGS 14 and 15 are sectional side ~iews of the
steps of forming a clinched joint of a third embodiment;
35FIG 16 is a sectional side view of the
.,
WOg3/l0925 PCT/AU92~00631
,, 2~23~6
clinched joint of the ~hird embodLment;
FIG 17 is a sectional side view of a semi-
tubular rivet or slug;
FIGS 18 to 22 are sectional side views of the
~ 5 steps of forming a clinched joint of the fourth
`" embodLment;
$ FIG 23 is a sectional side view of the
clinched joint of the fourth embodLment;
FIG 24 is a (a) top plan, (b) sectional side,
and (c) bot~om plan view of a ring;
~j FIG 2S is ~ sectional view of the clinched
! joint of the fifth embodiment;
FIG 26 is a sLmilar view of a modified form of
the clinched joint of FIG 25;
FIG 27 is a (a~ top pl~n, (b) sectional side,
and ~c) botto~ plan view of a c~mponent;
FIG 28 is a sectional side view of a clinched
joint of a sixth embodiment;
FIG 29 is a s~milar v:iew ~f a modified form of
the clinched joint of FIG 28;
FIG 30 is a (a~ top plan, (b~ sectional side,
and (c) bottom plan view of a second component;
FIG 31 is a sectional side view of a clinched
joint of a seventh embod ~ent; and
FIG 32 is a sectional side view showing the
;; clinched joint of FIG 31 where the oompo~ent is
supported in a die.
~ D~TAILED D ~ EMBODINENTS
i~ Referring now to~ FXGS 1 to 6, the t~bular
rivet 10 of FIG 1 is driven into the metal panels to
form the clinched joint 11 of FIG 6.
The metal panels 12, 13 to be joined together
are supported on the die assembly 14 of a clinching
tool(s~, the die assembly having e~pandable and
contractable collets 16 associated with a collet holder
~ WO 93~10925 PCr/AlJ92~00631
2123~6
.: 7
17 and anvil lB arranged to allow the joint 11 to be
~', released when formed.
The ::linching tool 15 has a pre-cl ampir~g head
19 which clamps the metal panels 12, 13 to the die
.i 5 asse~nbly and has internal ( sprîng~loa~ed) b~lls l9A to
~, locate and centralise the rivet 10. A punch 20 is
slidably journalled in a sleeve 21, slidably journalled
in the pre~clarnping head 19, and the punch 20 and
sleeve 21 are co~nected to respective hydraulic rams
( not shown ) .
The operation of the clinching tool 15 s~Jill
now be described.
After the metal panels 12, 13 are clam~ecl to
the die assembly 14 by the pre-clamping head 19, the
punch 20 is driven thr~ugh the rivet 10 into engage~nent
'~t~ with the upper panel 12; the sleeve 2~ engaging the
ri~et 10. The pun~h 20 and rivet 10 are ad~ranced to
deform the metal panels 12, 13 into the die assenlbly 14
( see FIG 4 3 . The sleeve 21 is then advanced to c:2luse
~j 2û the inn~er end of the rivet 10 to be outwardly-defonned
,~t ( see F~GS 5 and 6 ) .
The anvil 18 can be spring-loaded or forcibly
raised as a post-forming operation against the punch 20
to assist in defor~LLng the rivet or slug.
The insertion ar~d deformation of the rivet
- assists in lockir~g the metal panels 12, 13 together,
with increase in the shear a~d axial separation
strength~s) (ie. in the direction of arrows A and B,
respectively).
The bore 22 of the rivet 10 may be threaded to
recei~e ~ fastener or plug to support, ey. an electrical
wirin~ loom or a plastic insert to form a flush cover
for the clinched joint 11.
'! Referring now to FIGS 7 to 12, a modified
;,"J
i~l 35 tubular rivet 110 has a tapered end 12~ to its inner
"
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~ WO93/10925 PCT/AU92/00631
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?~23~ & 8
. bore 122.
' In this one-stage method, the sleeve 21 is
`~eliminated and the punch 120 is slidably journalled in
`.the pre~clamping head 119. The metal sheets 112, 113
~,'!5 are supported by the die assembly 114 and clamped
thereto by the clamping head 119. The punch'f~0 engages
the rivet 110 (see FIG 9) and drives the rivet 110 into
the metal panels 112, 113 which are deformed into the
die assembly 114 (see FIG 10). The punch 120 is further
.,;10 advanced (see FIG 113 to deform the inner end of the
'~rivet 110 to form the clinched joint 111 (see FIG 12~.
;,,To increase the strength of the clinched
joints 1.1, 111, a solid or semi-tubular rivet or slug
may be used.
Referring now to FIGS 13 to 16, a solid slug
210 (FIG 13) has a concave recess 222 at its lower end
.,
and is used to form the clinched joint 211 of FIG 16.
The metal sheets 212, 213 are clamped to the
die asse~bly 214 by the clamping head 219 ~see FIG 14).
The punch 220 is advanced to drive the slug 210 ~as an
extension of the punch 2203 into the metal panels 212,
1i 213 to deform the panels into the die assembly 214 to
~j fo~m the clinched joint 211. It will be noted that the
head of the sluy 210 is flush with ~he outer face of
pa~el 212 and such a joi~t is suitable where aesthetic
appeal is required, eg. on a visible surface of a
vehicle body.
j The semi-tubular slug 310 (see FIG 17) has a
tapered end 323 to its bore 322.
In the two-stage process shown in FIGS 18 to
23, the metal panels 312, 313 are pre-clamped to the die
assembly 314 by the clamping head 319 and the punch 320
is advanced (see FIG 19) to form a conventional button-
type clinched joint 311A (see FIG 20). The punch 320
is retracted and a semi-tubular slug 310 is placed in
WO93/10925 PCT/AU92/00631
~I23~86
`, g
flf the clinching tool.
The pre-clamping head 319 clamps the panels
(see FI~ 21) and the punch 320 is advanced to drive the
slug 310 into the clinched joint 311A to deform the slug
310 to ~orm the clinched joint 311 (see FIG 23).
Referring now to FIGS 24 and 25, the~~rivets or
slugs (10, 110, 210, 310) may be substituted by a Imetal
or plastic) ring 410 which engages the lowff-ffr panel 413
~,fto lock the clinched joint 411, the panels 412, 413
'110 being deformed into the divergently tapered bore 422 of
the ring 410. The ring 410 is supported by a die
~,assembly (not shown) as the punch Inot shown~ deforms
vfthe panels 412, 413, the ring 410 acting as the die
: body.
15As shown in FIG 26, straps or clips 424 may ~e
l~ fonmed integrally with the ring 410, eg, to secure
', wiring to a vehicle body. If re~uested, the ring 410
can be combined with the method of FIGS 17 to 23, where
a solid or semi tubulfr slug is pressed into the
f f
~20 clinched joint 411 to fo~m a flush surface with panel
j~ 412.
A component 510 (see FIGS 27 to 29), with a
tapered recess or bore ~22, and a screw-threaded hole
525 (as part of a sub-assembly - not shown) can also be
employed as the die for the cl~nched joint Sll and
provide a mou~t for the sub-assembly secured to the
panels 512, 513.
As shown in FI~ 29, a solid slug 210 can be
pressed into the clinched jaint 511. (The slug 210 may
be screw-threaded and ha~e a slot, Philips-head slot or
~;an Allen-head recess to enable the slug 210 to be
~¦removed later if required for dis-assembly of the joint
~11. )
FIGS 30 to 32 show the attachment of a second
3~ component 610, with a bore 622 and a plain spigot (FIG
30) or screw-threaded end spigot 626 (FIG 31), secured
1,
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' 10
3~ clinch-joint 611. ~The spigot may also be
profiled, eg. engage~le in a catch or lock means. ~
FIG 32 shows the component 610 supported by a
die assembly 614 during the clinching stepO
5In the methods shown in FIGS 24 to 26; 27 to
29; and 30 to 32, two panels 412, 413; 512,--513; 612,
:~ 613 are shown secured in the ring ~10, and c:omponents
510, 610. The methods are al50 applicable to securing a
single panel to the ring 410 on components 510, 610.
`;~ 10In addition, in all of the methods, on~ or
'~ both panels may be a polymeric sheet ~ eg.
polypropylelle ), it being pref erred that the inner sheet ,
eg. 13 " 113 ) being the polymeric sheet and the die
assembly may be heated at the location of the clinched
. 15 joint to assist "flow" of the polymeric material.
~ For improved recycling, it is preferred t.. hat
.~ the rivets 10, 110; slugs 210, 310; ring 410; or
components 510~ 610 be of the same t~pe of material as
~he pane:ls as this will obviate the need for disass~ly
of the join~s.
As an indication of the advantage of methods
of ~he p:resent invention, the use of an 8mm solid ri.vet
or slug in conjunction with a clinched joint increase
the shear strength of a sheet metal joint by 50% and the
strength to both the shear and axial separatian
directions can be maintained within controlled limits,
~, unlike spot welds. This mea~s the number of clinched
joints ca.n be much less th~n the number of spot welds,
and the joints can also support sub-assemblies.
Various changes and modificatio~s may be made
to the embodiments descr.ibed and illustrated without
departing from the scope of the present invent.ion
., defined in the appended claims.
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