Note: Descriptions are shown in the official language in which they were submitted.
- l.Z~30~7~
METHOD AND AppARArus FOR MARING
A PULL CORD EXTEMSION ASSEMBLY
Background of the Invention:
: Field of the Invention:
The present invention relates to a method of making an
assembly. More particularly, the present invention is directed
towards the ~ethod of making an extension assembly including a
~: 5~ conneceor for bead-cbain, a tassle and b thin flexible line
joinlng the connecto tv the tassle.
`
.: :
~: : : Background of the Invention:
Pull cord extension assembl~ies, generally used to operate
. switches in pull-chain lamps and t~hè like, are attached to the
:10 switches' bead-chains by their connectors and are pulled by the
tassle to operate~the ~wltches,:~
Methods for their manufacture, according to the present art
require individual attention to each assembly. ~or the
connector, one end of the f1exib1e line is installed within and
a knot i~ tied which mUct be kept to what mby be considered
:106e tolerance~ in view of the material in which it is tied.
~,
~:,:
::, 1
:`~':
~'~
;, ,
,; :
1 ' ~' . . `
~ ' . : .`, `: ' '
If the knot or th~ rem~ining line end ~s too large, an
interference will develop for later in~tall~tion of the
connector to the bead-chain For the tassle, the other end of
the line 16 in~talled and a knot must be tied that i6 not so
5 large that it protrudes from the interior of the tassle or so
small that the line can be pulled ~ack ~ut of the tassle when
the tassle is pulled ~o operate ~ switch.
In accordance with the invent~on, ~ connector having a chain
entry and hold area and a tassle are molded on a portion of the
line, joined together and positioned so that the line is
captured in each, while in the connector is not in interference
with the chain entry and hold area. The line is moved a
predetermined distance and the operation is repeated on another
portion with the second molding oriented so that the ~econd
connector molded is attached by the line to the first tassle
: molded. The operations repeat on a continuous line whereby the
pull cord asse~blies may be stored end to end on a pick up
~pool.
.
~ach assembly is attended to ~eparately and the methods
presently used do not lend themselves to economical automated
manufacture.
, . . .
,
-" 1280~37~7
Summary of the Invention:
It is one object of the invention to provide a method of
making a pull chain assembly which provides continuous, unbroken
manufacture, rather than constructing each assembly on an
individual basis.
It is another object of the invent~on to provide a method of
molding the sssembly.
It is another object of the invention to provide simultaneous
automatic~olding of large numbers of assemblies.
~ ~ 10 Yet an~other object~ of the inventlon is to provide a connector
with permits attachment of the chain without interference from a
; knot.
And another object of the invention is to provide an apparatus
for manufacturing the pull~chain assemblies according to the
method of the invention.
Other objects and advanta~es of the ~invention will be
~ ~ ~pparent to one killed in the art~
:
~: :
:: : :
:
'.
.
,. .. . . .
....
,,.~.. ,".. . :' ,', ~ .
~L280~37~7
_ ief Description of the Drawin~s:
Figs. 1 and 3 are axial sectional views of a presently used
connec~or and tassel with partially attached line~.
Figs. 2 and 4 are perspective views of a connector and a tassle
made by the present invention.
Fig. 5 is ~ perspective view of the connector of Fig~ 1.
.
Fig. 6 i~s a front elevational~view of an apparatus for carrying
out the method of the invention.
Fig 7. is a plane view of an apparatus for carrying out the
method for ~imultaneous manufacture of six assemblies.
Fig. 8 is a front elevational axial section view of a mold
cavity block for ~imultaneous manufacture of six assemblies.
Fig. 9 i~ partial ~ectional view of an apparatus for carrying
out the ~ethod of the invention.
; Refer~ing now to the drawin~s, comparison may be made
between: a) present type connector 1 Figs. 1 and 5 for
, : -
bead-chain 2 and flexible line ~uch a~ a ~tring 3, and tassel 13
Fig. 3 for flexible line ~uch as a string 3 and; b) connector 4
.~
.
~.:
.
~,,
.
, .. ~ , ---. . . ~
. . .
, . . .:: ::: . '
~8~7~
Fig. 2 for bead-chain 2 and line 3, and tassel ll for line 3,
which ~ay be made by the present invention.
Installation of line 3 in co~nector l req~ires several
operations which are: positioning the line through hole 5,
through hollow connector shell 6, through shell opening 7, tying
retaining knot 8 in the line's connector end 9 and then pulling
the line back through hole 5 until the knot i8 ~ituated within
the connector'~ shell. The distal end lO of line 3 continues
tnot shown) on to connect to tassel 33 shown in ~ig. 3 where it
; 10 is Installed by p~sitioning it through hole 12, through ~hell
; 13, through opening 14, tying retaining knot 15, then drawing
the line ~ack through hole 12 until knot 15 is situated within
the tassel's shell.
Connector 4 ~ig, 2 and tassel 1l Fig.4, on the other hand
~; ~15 are molded by in]ection molding or other ~ethod with the line on
a continuous bas16 by the~present invention as will be explained
with reference to the remaining drawings, thus eliminating the
above slow and costly operations.
:
.
~Connectors l;and 4 of Figs. l and 2 are used to attach their
:
20 re~pective lines 3, 3 and tassels 33, 1l of Figs. ~ and 4 to
bead-chain 2. The distal end tnot shown) of bead-chain 2 is
normally attached to a ~pul1 chain switch~ mechanism of the type
often included in pull chain light fixture- socket~.
':
~ .
, ~ ,
,~
' :
.
77
The bead-chain is attached to either type connector in 8
similar manner. In presently used connectors Figs. 1 and 5, a
bead 17 of chain 2 i5 in~erted into opening 7 and positioned ~o
that its link 18 with the remainder of the chain is slidably
5 located in slot 19. The chain ic then pulled so that the lini:
slides back to opening 16, thereby capturing the inserted bead
and with it~ the chain.
Difficulty often arises in th;s connector, between
attachment of tbe line and the chain. The knot must be ~ade
large enough to prevent slipping out ~hrough opening 5, yet it
must be small enough, and line end 9 must be cut short enough
~ ~ without affecting knot integrity, to provide clearance for bead
s; entry in:to opening 7. In turn, if the chain is attached first,
~ the bead extends over part of opening 7, complicating attaching
.i ~
~:: 15 of the line.
`,~; ~ '
In the connector made by the present invention, Pig. 2 the
chain~ is installed by inserting a bead 17 of chain 2 into
opening 20 with link 18 slldably located in ~lot 21. The chain
i8 then pulled &0 ~hat link 18 m~ves to opening 22, thereby
: ~ 20 oapturing the chain by the inserted bead. There is no
interference between line 3 and the chain as described earlier
`;~ because,~ during operation of the Invention, it was molded both
.;~ with its end displaced from the connector's centerline and
excluded~from the chain entry and holding areas comprising
~ocations 20, 21, and 22.
.
. .
.
:. , .~, . :
:~,. .. . ' ' :
In the tassel 11, Pig. 4 made by the present invention, line
3 i8 automatically tnolded in and no further assembly is
necessary.
According to the method of the in~ention ill~strated b~ Fig.
6, there is provided line 3, loaded on supply spool 23 ~ounted
for rotation on frame 24. The line is intermittently drawn
s~raight to pick up spool 25, mounted on base 24 at a suitable
d;stance from spool 23~ Injection mold split cavity block 26
and mating head 27 are mounted for operation between the two
spools so that may close on the line without deflection which
would cause the line to be drawn foward or back from the spools.
~,
In operation, the mold is closed on line 3, capturing a
portion of it in mold cavity 28. Plastic is injected into the
cavity by way of channel 29 to sprue~channel 30 in a
1S conventional manner for injection molding that is known to the
art. After a molding cycle is completed the molded is opened
and the line is advanced tQward the take up spool for a distance
equal to the line length desired on the finished Pull Cord
~xtension Assembly. ~ach molding cycle re~ults in a connec~or
joined by gate 31 and sprue to a tassel. The cycle is repeated
with each line advance so that continuous sets of pull cord
extention assemblies;are ~ade, attached to each other by the
gstes and ~prues. The gates and sprues may be formed so that
the ~prue ~erves to feed plastic to the gate and plays little
'
,
' ~
. ; : :
.
~L280~3~7
part in direct joining between the connector and tas~el. For
minimum leakage during molding, it i8 preferred that the line is
routed through the cavity by way of the two gate channels. It
mav also run across the sprue channel as well, if the spring
inte~ceptE it.
Figs. 7 and 8 illustrate simultaneous forming of assemblies
on a si~-bank machine frame 34. Mold cavity block 35 and mating
head 3~ operate to simultaneously mold connectors 4, tassels 11
~ith the sprue and their attachment gates which incorporate the
line within them. Connectors' 4 cavities are positioned with
their tips concentric with line 3 and their axis slightly angled
from that of the line line so that the line is captured in
plastic~ outside of chain entry and hold areas comprising
opening 20, slot 21 and opening 22.
After each molding cycle, pick up spools 25, mounted on
drive shaft 37, draw the molded strip of parts from the open
mold. Supply spools 23 mounted on shaft 38 ~upply the
contlnuous lines. ~eating elements 39 are provided to
accommodate the molten-plastic supply channels 40 as shown in
Fig. 8.
It i~ within the cont-emplation of the invention that
~pacing/cutting station ~1 $s provided for ~ectioning the sprue
80 that each line of pull cord extension assemblies may be wound
... .
. . :, : ..
, : ` ' ' '~ . ` ': ' ` ' ' `
` ` ` ,. ,.. : . ~:
`'` :,'
for storage on the indi~idual take up ~pools on shaft 37. It
also serves to stop the lines for the next cycle ~fter the
molded strip has been moved a suitable distance from the mold
cavity. Foward and reverse clutch or other tension means may be
used to take ~p slack,
: It is also within the contemp1ation of the invention that
molds may be sequenced along lengths of the line for
; simultaneous molding, wherein the line is moved a distance
: sufficient to clear the molded part~ from the cavities and
provide proper~line lengths ~or the next molding as discussed
~; supra.:
~: :
-: :
In the embodiment shown in Figs. 8 and 9, heating elements
facilitate bringing molten plastic directly to the gate
channels, eliminating the sprue. :Plastic:injection 6upply 42
~: 15 delivers molten plastic shots by way of heated channel 29 to
:
old cavity 28 to for~ connector 4, gate 31 and tassel 11 as one
unit on each line which has its own supply spool 23, ~pring
; loaded tensioner assembly 43 for minimi~zing slack in the line,
supply~guide r~oller 44 and pick-up guide roller 45 to keep the
line straight, and pick up spool 25. Clamping ~tation 46 may be
.~:
used to control l~ine travel~:between each cycle to overcome
: pick-up 6pool diameter change a6 it collects the pu11 cord
extension assemblies for storage~: `
;
, ~ ~
:: :
.
:;: . , -:
:,
~'~8~37~
When it i6 desired that the pull cord extension assemblies
be separated for packaging or u6e, they ~ay be cut; t~ssel 11
Fig. 4 at line end 37 and connector 4 ~ig. 2 at line end 3B.
In vie~ of the preceeding description, i~ is seen that the
present invention provides a method for making a pull cord
extension assembly which reduces time and cost in attaching the
line between connector and tassel including a knot tying
operation, provides si~ultaneous automatic ~olding of large
numbers of assemblies, and provides a connector which permit~
attachment of the chain without interference from a line knot.
Although va~ious embodiments of the lnvention have been
described and shown, it is obvious that varioas modifications
an~ changes can be made without departing from the ~cope of the
invention which shall be limited by only the follawing claims.
'~
.
`
- 10
: : ,. . . .
~ '~.. ',.. .
. . ~ .
,'' .' ''
