CA1167743A

CA1167743A - Spring coiling machine with improved cut-off means

Info

Publication number: CA1167743A
Application number: CA000394090A
Authority: CA
Inventors: Bernard P. Lampietti
Original assignee: Torin Corp
Current assignee: Madison Management Group Inc
Priority date: 1981-01-14
Filing date: 1982-01-13
Publication date: 1984-05-22
Also published as: DE3266585D1; BR8200144A; ATE15867T1; EP0056330A2; JPS57134226A; EP0056330A3; JPH0223253B2; EP0056330B1

Abstract

ABSTRACT OF THE DISCLOSURE
A cyclically operable spring coiling machine includes a pair of feed rolls for intermittently advancing wire longi-tudinally to a coiling station at an upper portion of a vertical front frame of the machine. A coiling arbor and a coiling tool at the station cooperatively form leading end portions of the wire to a coil spring configuration and an improved cut-off means severs the coiled leading end portions of wire to provide individual coil springs. The improved cut-off means includes a pair of tool holders on opposite sides of the coiling arbor movable toward and away from the arbor and wire coiled thereabout and generally in opposition to each other. The holders are employed selectively depending on the hand of the spring being coiled and are respectively mounted on pivot shafts extending rearwardly through the front frame of the machine and geared together at rear end portions. A continuously rotating horizon-tal shaft forming a part of the coiling machine drive mechanism has a front end portion projecting through the vertical front frame of the machine. An eccentric on the front end portion of the shaft drives an oscillable arm which in turn has a pivotal connection with a lowermost tool holder through an adjustment means. The adjustment means comprises complementary threaded members operable to adjust the movement of the tool holders and thus to vary throw of a cut-off tool thereon toward and away from the coiling arbor.

Description

I.~ '7'7~

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 ,., ;~
,~"

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 ;'7';'~3 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 ~'1 ti'7'74~

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 ¦

'~ _5_ 1 1~ "i"'L3 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 7 7~Q3 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 '7'~

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 ~ 7~

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 (i ~ 7~

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.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a cyclically operable spring coiling machine having a vertical front frame and a coiling station at an upper portion thereof; the combination of at least one pair of oppositely rotatable feed rolls on said frame for inter-mittently advancing wire longitudinally to the coiling sta-tion, a relatively fixed coiling arbor at the coiling station, at least one coiling tool at the coiling station arranged to engage the longitudinally advancing wire to obstruct the linear movement thereof whereby progressively to bend the same about the coiling arbor and impart a coiling stress there-to resulting in the formation of a coil spring configuration at a leading end portion thereof, an anvil means at said coiling station, a pair of cut-off tools at said coiling stations gen-erally on opposite sides of said coiling arbor and co-operable with said anvil means intermittently to sever coiled leading end portions of the wire whereby to provide individual coil springs, a pair of holders for said cut-off tools movably supported on and exposed at the front of the machine frame for urging the cut-off tools toward and away from the anvil means and wire coiled thereabout, connecting means between said tool holders for moving said tool holders in unison but in generally opposite directions towards and away from the anvil means, a continuously rotating horizontal shaft forming a part of the coiling machine drive mechanism and having one end portion pro-jecting forwardly through the vertical front frame of the machine beneath and in spaced relationship with said tool holder, and motion transmitting and converting means exposed at the front of the machine frame and connected between said projecting end portion of said shaft and one of said tool holders and operable to effect a single tool holder and cut-off tool movement to-ward and away from said anvil means and wire coiled thereabout during each rotation of said shaft, said motion transmitting and converting means comprising an eccentric mounted on the forwardly projecting end portion of said continuously rotating shaft and an associated arm oscillable thereby to effect the tool holder movement as aforesaid; said oscillable arm including an adjustment for changing the throw of said cut-off tools to-ward and away from the anvil means and wire coiled thereabout.

2. The combination in a cyclically operable spring coiling machine as set forth in claim 1 wherein said motion transmitting and converting means arm has a pivotal connection with said one tool holder, and wherein said tool holders are pivotally supported on said frame for swinging movement thereof and cutting tools thereon toward and away from the anvil means.

3. The combination in a cyclically operable spring coiling machine as set forth in claim 2 wherein a second tool holder is provided on a side of said anvil means generally op-posite said first tool holder, and wherein connecting means between said tool holders for moving said tool holders is uni-son but in generally opposite directions toward and away from the anvil means.

4. The combination in a cyclically operable spring coiling machine as set forth in claim 3 wherein said first and second tool holders are each provided with pivot shafts projec-ting rearwardly through the machine frame in parallel relation-ship, and wherein said connecting means includes drivingly interconnected gears respectively mounted at rear end portions of said pivot shafts.

5. The combination in a cyclically operable spring coiling machine as set forth in claim 4 wherein said anvil means comprises anvil-like edges on said coiling arbor posi-tioned to align generally with cutting edges on said cut-off tools when said cut-off tools are moved -toward -the coiling arbor in a cut-off operation.