Note: Descriptions are shown in the official language in which they were submitted.
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SP~ING COILING r~ACHINE WITH IMPROVED CUT-OFF MEANS
BACKGROUND OF THE INVENTION
Cut-off operationsl the severing of a coil spriny formed
at a leading end portion of wire, have been accomplished in
prior art spring coiling machines by cut-off -tools cooperatlng
with an arbor about which the springs are coiled. That is,
at the end of a coiling operation, a cut-off tool mounted on a
pivotal tool holder is swung into engagement with the wire at
the desired position and usually with an anvil-like edge of
the coiling arbor immediately therebehind. Holders for the
cut-off tools are conventionally mounted on opposite sides o~
the coiling arbor for selective mounting of cut-off tools there-
on for left and right hand springs. The tool holders have been
conventionally operated from a cam behind the front frame of the
machine and with a relatively complex driving mechanism including
push rods etc. operating between the cam and the tool holder.
Such tools and operating mechanism have been generally satisfac-
~ory but certain difficulties have been encountered particularly
in high speed operation of spring coiling machines. The drive
mechanisms have tended to be noisy, sometimes inaccurate in op-
eration and with the substantial cut-oEf forces required, actual
bouncing of the cam follower on the cam has been encountered.
It is the general object of the present invention to
provide a spring coiling machine having an improved cut-off means
which e~hibits a high degree of accuracy and dependability in
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use particularly in high speed operation and ~hich has a high
degree oE structural strength and integrity as required to ef-
ficiently absorb reactive forces during cut-off operations,
readily accessible adjustment means also being provided in ex-
posed position negating the requirement for internal adjustment
behind the front frame of the coiling machine.
SU~i~R~ OF T~IE INVENTION
In fulfillment of the foregoing object, a cyclically
operable spring coiling machine having a vertical front frame
and a coiling station at an upper portion thereon is provided
with at least one pair of oppositely rotatable feed rolls for
intermittently advancing wire longitudinally to the coiling
station. A relatively fixed coiling arbor at the coiling station
is off-set slightly with respect to the line of wire feed move-
ment so that the wire is advanced along one side of the arbor.
Preferably, the arbor has generally oppositely oriented anvil-
like edges for copperation with a cut-off tool in a cut-off
operation. At least one coiling tool is providedat the coiling
station and is arranged to engage the longitudinally advancing
wire to obstruct the linear movement thereof and thereby to
progressively bend the wire about the coiling arbor and impart
a coiling stress thereto resulting in the formation of coil
springs. At least one cut-off tool at the coiling station in-
cludes improved operating means and serves intermittently to
sever coiled leading end portions of the wire whereby to provide
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individual coil springs.
A holder for the cut-off tool is movably supported on
and exposed at the front of the machine frame for urging the cut-
off tool toward and away from anvil means which may be on -the coil-
ing arbor. In movernent toward the coiling arbor the cut~off
tool engages the wire at a selected position and w,ith an anvil-
like edge of the arbor therebehind severs the wire as required.
Preferably, a second tool holder is provided generally opposite
the first tool holder and is adapted to carry a cutting tool for
operation similar to that described but for a spring of opposite
hand. ~hen a second holder is provided, a connecting means be-
t~een the tool holders serves to operate the same in unison
but generally in opposition to each other. Preferably, first
and second pivot shafts are provided respectiveiy for the tool
holders with interconnecting gear means at rear end portions
thereof. Thus, the tool holders are operated in unison ~ut
under ordinary circumstances only one of the tool holders car-
ries a cut-off tool.
An operating means for the tool holders ta~es the form
of a continuously rotating horizontal shaft which forms a part
of the coiling machine drive mechani,sm and which has a front
end portion projecting through the vertical front frame of the
machine beneath and in spaced relationship with the tool holders.
A rugged and accurate motion transmitting and convertins means
is e~posed at the front of the machine and is connected bet~een
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the projecting front end portion of the continuously rotating
shaft and a first tool holder. The motion transmitting and con-
verting means, preferably including an eccentric on the shaft
and an osci~lable arm operated thereby, serves to effect a single
tool holder znd cut-off tool movement toward and away from the
coiling arbor and wire coil thereabout duxing each rotation of
the shaft.
'rhere is preferably also included an adjustment means
which may comprise cornplementary threaded elernents between the
oscillable arm and the first tool holder. The said adjustment
means serves to adjust the position of the cut-off tool toward
and away from the cutting arbor as may be required for various
coil springs. Further, the adjustment means is exposed and readi-
ly accessible at the front of the machine for ease and convenience
in effecting necessary adjus~ments during set-up operations of
the machine.
_RIEF DESCRIPTIO~ OF THE DR~I~INGS
Fia. 1 is a somewhat schematic illustration of a
spring coiling machine viewed from the front and including the
improved cut-off means of the present invention.
Fig. 2 is a somewhat schematic view taken from the rear
of the machine of Fig. 1 and illustrating various drive means
in the machine associated with the operating means of Fig. l.
Fig, 3 is a fragmer.tary enlarged and somewhat schematic
view sirlilar to Fig. 1 but better illustrating the improved cut-
v off means of the present invention.
Fig. 4 is a fragmentary enlarged and somewhat schematic
vertical section ta~en generally as indicated at 4,4 in Fig. 3.
DESCRIPTION OF PREFERRED E~ODIMENT
I
¦ Referring particular;Ly to Fig. 1 it will be observed
¦ that a spring coiling machine indicated generally at 10 has
first and second pairs of oppositely rotatable feed rolls 12,~4
and 16,18 for advancing wire :Longitudinally leftwardly io a
coiling station indicated generally at 20. In Fig. 1, the upper
feed rolls 12,16 rotate in a clockwise direction and the lower
feed rolls 14,18 rotate in a counterclockwise direction -to feed
wire 22 leftwardly through guides 24,26 and 28 for the formation
' of the wire into a coil spring configuration 30 at its leading
end portion. As best illustrated in Fig. 3, the leading end
¦ portion of the wire 22 is coiled about a coiling arbor 32 at
; 15 I the coiling station 20, the arbor 32 cooperating with a coiling
tool 34 in the form of a coiling roll. Coiling arbor 32 and
coiling tool 34 are relatively fixed at the coiling station
so that longitudinally advancing wire engages the roll 34 and
is obstructed in its linear movement thereby, the wire thus being¦
progressively bent about the arbor 32 with a coiling stress im~
parted thereto resulting in the formation of ~he leading end
coil spring configuration 30.
~ihen the leading end portion of the wire 22 has been
coiled through the desired number or convolutiGns about the
arbor 32 it s severed from the remaining portion of the wire 22 ¦
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by means of a cut-off tool indicated at 36, individual coilspringc
thus being formed. Element 38 at the coiling station 20 may take
the form of a pitch tool engageable with the wire during coiliny
about the arbor 32 progressively to pitch the same as required
for the coil spring to be formed. Element 39 is a final wire
guide which cooperates with an upper surface of the pitch ~ool in
guiding ~he wire 22 immediatels7 prior to coiling of the wire.
The cut-off tool 36 is mounted on a tool holder 40 and
cooperates wi-th a separate anvil means or an anvil-like edge 41
formed on the coiling arbor 32. Sirnilarly, a tool holder 42 dis-
posed above the coiling arbor 32 may carry a cut-off tool such
as the tool 36 for cooperation with a separate anvil means or a
; second anvil-like edse 43 on the coiling arbor. The tool holders40,42 are movable toward and away from ,he coiling arbor 32 and
wire coiled thereabout to effect cut-off operations cooperatively
by a tool held thereby and the anvil-like edges ~1,43 on the
arbor. Thus, springs of opposite hand can be accommodated by
selectiveiy employing a cut-off tool on the holdexs 40,42.
~s thus far described and illustrated schematically,
2~ the spring coiling machine 10 is or may be conventional and for
further illustration and description of such a machine including
operating means for elements such as the feed rolls, the pitch
tool 38 etc. reference ma~ be had to Bergevin and Nigro U.S.
Patent No. 2,119,002 for Spring Coiling ~5achine, dated May 3, 1938
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ancl Bergevin U.S. Patent Re. 24,345 for Spring Coiling Machine
da-ted August 20, 1957. The machines shown and described in
these patents, however, are of the segment drive type and while
highly accurate and dependable in operation -they are limited
as to the rate of spring production achievable thereon. On
the other hand, a high speed spring coiling machine is shown
and described in Canadian Paten-t No. 1,114,041, dated April
5, 1983, for Spring Coiling Machine With Improved Feed Roll
Drive Means, Inventors Erman V. Cavagnero and Nicholas J.
Marracino. The improved cut-off means of the present invention
finds utility in either -type of spring coiling machine but is
particularly well suited to the high speed machine of the co-
pending application.
Referring particularly to Figs. 3 and 4, it will be ob-
served that the spring coiling machine 10 has a substantially
vertical front frame 44, Fig. 4 and the tool holders 40,42 are
mounted forwardly thereof and movable relative thereto. Pre-
ferably the tool holders 40,42 are pivotally mounted respectively
on pivot shafts 46,48 which project forwardly through the frame
44 of the machine, are journaled respectively at 50,51 and which
extend substantially in parallelism rearwardly in the machine.
Connecting means between the shafts 46,48 may vary but preferably
take the form of drivingly engaged gears 52,54 at rear end por-
tions of the shafts 46,48 respectively. Thus, when one of the
tool holders 40,42 is operated pivotally the other tool holder
is movable in unison therewith but generally in an opposite
direction. In Fig. 3 the lower tool holder 40 of course swings
in a clockwise direction in a cut-off opera-tion while the upper
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tool holder 42 swings in a counterclockwise direction in a
cut-off operation. In the presently preferred form of the in-
vention the lo~er or first tool holcler 40 is operated by a drive
mechanism to indirectly operate the tool holder 42 through the
shafts 46,48 and gears 52,54. Gbviously in a set-up operation,
a cutting tool 36 may be mounted on the tool holde~ 40 or, al-
ternatively, the tool 36 may be mounted on the tool holder 42
depending upon the hand of the spring to be severed.
Further in accordance with the invention, the lower
or rirst tool holder 40 is operated from a horizontally extending
and continuously rotatiny shaft 56 which forms a part of the
coiling machine drive mechanism and which has a front end portion
thereof projectins forwardly through -the vertical front frame
44 of the coiling machine. The shaft 56, as best illustrated in
Figs. 3 and 4 is disposed beneath and in spaced relationship
with the tool holder 40 and, as illustrated in Fig. 2, is driven
¦ ~y a gear 58 in turn driven by year 60 and gears 62 and 64. A
belt pulley arrangement drives the gear 64 from a drive motor
and speed reducer unit 66 in Fig. 2. As will be apparent, -the
shaft 56 is one of the main drive or operating shafts of the
spring coiling machine and of course may include other operating
means such as cams etc. rear~lardly of the front frame of the
machine.
A motion transmltting and converting means exposedat the
front of tihe machine and connected between the shaft 56 and the
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tool holdex 40 is operable to effect a single tool holder and
cut--off tool movement toward and away frorn the coiling arbor 32
during each rotation of the shaft 56. Thus, the cut-off opera-tio
may be readily tlmed for occurrence once during each cycle of
machine operation. ~n presently preferred form, the motion
transmitting and converting means includes an eccentric 58 moun-
ted on the forwardly projecting end portion of the shaft 56 and
operatively associatecl with an oscillablearm 60. ~he osc~llable
arm 60 is thus provided with a component of movement toward
and away from the tool holder 40 at a pivot pin 62 which con-
nects the motion transmitting and converting means to the tool
¦ holder. A bifurcated bracket 64 carries -the pivot pin 62 and
imparts the desired movement to the tool holder 40 in pivoting
the holder about its pivot shaft ~6 as required.
Preferably, an adjustment means forms a part of the
motion transmitting and converting means and is interposed be-
tween the arm 60 and the bracket 64. The adjustment means may
vary in form but as shown comprises complementary threaded ele-
ments adjustable to vary the throw or degree or amount of move-
ment of the holder 40about its pivot shaft 46. Thus, springs
of various diameter and wire size can be readily accommodated
in a set-up operation. The adjustment means is readily accessibl ,
from the front of the machine facilitating such set-up operation.
As shown, the adjustment means comprises threaded member 66
which enters internally threaded member 68 supported for rota-
tion in an upper end portion of the arm 60. The member 68 may be
rotated to effect the necessary adjustment with lock-nut 70 in a
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loosened condition and, thereafter the lock-nut 70 may be tight-
ened to secure the adjustment means in the desired position of
adjus-tment.
From the foregoing it: will be apparent that the improv-
ed cut-off means of the present: invention is of rugged and hi.ghly
accurate construction. The cut,-of means is operated from one
of the main shafts of the spring coiling machine by direct con-
nection with an eccentric and oscillable arm having the characate~
istics of positive and accurate movement. Further, necessary
ad~ustments auring set-up operations can be effected with a
high degree of ease and convenience. The adjustment means is
exposed and readily accessible at the front of the machine elimi-
nating any .,eed to gain entry to and effect adjustments internally
of the rnachine in areas of difficult accessibility.
