US2141588A - Spring knotting machine - Google Patents

Spring knotting machine Download PDF

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Publication number
US2141588A
US2141588A US164330A US16433037A US2141588A US 2141588 A US2141588 A US 2141588A US 164330 A US164330 A US 164330A US 16433037 A US16433037 A US 16433037A US 2141588 A US2141588 A US 2141588A
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spring
head
carrier
slot
disposed
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US164330A
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Fred R Zimmerman
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NACHMAN SPRINGFILLED Corp
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NACHMAN SPRINGFILLED CORP
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21FWORKING OR PROCESSING OF METAL WIRE
    • B21F35/00Making springs from wire
    • B21F35/02Bending or deforming ends of coil springs to special shape
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21FWORKING OR PROCESSING OF METAL WIRE
    • B21F33/00Tools or devices specially designed for handling or processing wire fabrics or the like
    • B21F33/04Connecting ends of helical springs for mattresses

Definitions

  • the invention has for its main object to provide a simple and efficient machine for knotting upholsteryv springs of different, sizes and composed of wire of gauges commensurate with the size and load carrying capacity of the spring.
  • One of the objects of the present invention is to provide a knotting machine which performs each bending operation immediately preceding the knotting operation, so. thatboth said operations are performed substantially simultaneously.
  • FIG. 1 is a front elevation partly in section of a machine constructed in accordance with the invention.
  • Fig. 2 is a vertical sectional view of the machine taken on theline.2-2 of Fig.1.
  • Fig. 3 is a side elevation of the machine, also partly in section. b r
  • Fig. 4 is a view similar to Fig. 3 showing the operating parts of the machine in another position.
  • Fig. 5 is a fragmentary sectional viewon an enlarged scale, talgen on thejline 55 of Fig. 4.
  • Fig, .6 is a fragmentary top plan view of the machine.
  • v e V Fig. '7 is a fragmentary perspectiveview of an upholstery spring adapted to be knotted by the machine, showing a terminal end portion bent to overlap another portion thereof preparatory to effecting knotting'of the spring.
  • Fig. 8 is a view similar to Fig. 7 showing the completion of the knotting operation.
  • Fig. 9 is a perspective view of the coiling or knotting head of the machine.
  • Fig. 10 is a detailperspective view on an enlarged scale showing the spring carrying element of the machine. V A
  • the machine comprises a suitable frame equipped with bearings for actuating shaft l thereof, which carries a loose pulley 2.
  • a clutch member 3 constituting an element of a conventional punch-press clutch which will not be described because well known to those skilled in the art.
  • the engagement of the member. 3 with the pulley. 2 is manually controlled by means of a manually operable lever 55 (Fig. 2) which controls. the actuation of'said shaft l at the will of the operator and is actuated by a rod 56.
  • spur gear wheel 4 which, as shown in Fig. 2, is a segmental gear of a well-known type which meshes, during a part .of its revolution, with the spur gear wheel 5 on a countershaft 6.
  • Said spur gear wheel 5 meshes with a spur gear wheel 1 on a second countershaft 8 and the latter, in turn, meshes with the spur gear teeth of the coiling head 9, said spur gearteeth ll] of the head 9 being shown in detail in Fig. 9 and being shown also in dotted lines in Fig. 4.
  • the gear ratio between said spur gear wheel land the said coiling head 9 is such that at each complete revolution of said wheel other gear wheels for increasing or reducing the number of completelrevolutions through which the head 9 is rotated at each actuation of the wheel 4.
  • the coiling head 9 is equipped with a longitu- Tdinal slot H extending throughout its length and which is radially disposed, the innermost or end wall of said slot being semi-cylindrical and concentric with the axis of rotation of said head 9.
  • Said head is equipped at one end with what may be termed a cam member l2, also shown in Fig. 9, which is provided with a normally horizontally disposed top face l3 aligned with the diametric plane of the head 9 which is coincidental with the said slot ll thereof.
  • Said face l3 terminates at the innermost end of the slot H at one end and at the circumferential face of the said head diametrically opposite the mouth of the slot I I.
  • the said cam member I2 has an arcuate face which is flush with the cylindrical face of the head 9, the cut-away portion [4 of said cam l, the head 9 isrotated through a predetermined the ends of the member i9 is an anti-friction" roller 2
  • the cam 22 is equipped with a recess 24 and with circumferential or cylindrical face, the bot-' tom wall of said recess being concentric with the axis of rotation of said cam and the end walls of said recess being flaring and substantially ogee-curved, so that the roller 2! may ride easily out of the recess upon the circumferential face of the cam, and vice-versa, as the latter is rotated.
  • a springvcarrierplate 25 mounted upon the upperand outermost end portion of the member I9 is a springvcarrierplate 25, shown in detail in Fig. 10, which is disposed normally in forward position and'to one side of the head '9 when the latter is at rest, as shown in Fig. 3.
  • Said plate 25 is equipped with a raised portion 26 having parallel edges, one of which is flush with one side edge of saidplate 25 and has its other edge parallel with and spaced from the other side edge of said plate 25.
  • the end portion of the part 26 of the plate 25 has an arcuate front edge spaced from the front edge of the plate 25 and an arcuate shoulder 28 spaced from the arcuate edge 26a.
  • the plate 25 is equipped at its forward left hand corner, as shown in Fig.
  • a'projection 29 having an arcuate face which is opposed to the left hand forward corner of the arcuate edge 21. 1 j H
  • the terminal end portion of a-terminal coil 30 of a spring I5 is disposed in contact with the arcuate surface 2! of said part- 26 of the plate 25, and is engaged also by the projection 29, whereas, the next adjacent convolution I! of the spring is engaged, in part, by the arcuate shoulder 28. 7
  • an adjustable stop 3l against which the extremity of the terminal coil of thespring I6 is caused to abut in order to position the spring as desired in the machine preparatory to effecting knotting thereof.
  • a spring-clamping lever 34 Pivotally mounted between its ends upon a s ud shaft 33 carried by the member l 9 at a point substantially vertically aligned with the stud shaft 20, is a spring-clamping lever 34, one end of which is engaged with the tension spring 35 for maintaining said lever normally in the position shown in Fig. 3.
  • the machine'frame is equipped with an. upwardly projecting head 33 which is equipped with the bearing for the opposite end portions of the head 9, the said respective end portions of the latter disposed at opposite sides of the spur gear teeth It] being cylindrical and housed in said bearings.
  • the latter are equipped with slots which normally are aligned with the slot l l of said headS.
  • said head 36' is an adjustable shaft a 31 which carries an eccentric 38 disposed in the path of the substantially ogee-curved formation 39 of one end portion of the head Ml of the lever 34, said head 40 being provided with a recess 4! which is adapted to receive the portion of the convolution I! of the spring I8, shown in Fig. 6,
  • saidend portion'or head 40 of said lever34 being disposed angularly to the body of said lever as shown in Fig. 6.
  • the said shaft 31 is equipped at its other end Witha nut 42 by means of which it is clamped against rotation after effecting adjustment of the position of said. eccentric 38 relatively to the head 9 to cause said: lever 33 to firmly engage a portion I! of the spring l6 engaged with the shoulder 28 to clamp said spring against movement during the coiling operation, said eccentric being shown imposition wherein the head 4! of the lever 34 is adapted to engage a spring 16 composed of wire of heaviest gauge which the machine is capable of operating upon.
  • the said eccentric 38 will be/moved from the position shown in Fig. 3 to another position, depending upon the gauge of wire of the spring which is being operated upon.
  • the plate 25 is interchangeable with other similar plates wherein the arcuate shoulder 23 is of'less height in each instancethan the portion I? of the spring adapted to be engaged therewith, so that the said head 40 of the clamping lever 34 may engage said portion of the. spring disposed 'in engagement with said shoulder to clamp the same firmly against. the surface between the shoulders 28 and 21.
  • the terminal coil .of the spring 16 When the parts above described are disposed in the position shown in Fig. 4, the terminal coil .of the spring 16 will have its end portion l5 disposed in the position shown in Fig. 5 and the convolution I! of said spring will overlie said terminal portion it between the ends of the latter and will be maintainedfirmly in said position by means of said head 43 of the clamping lever 34.
  • the punch-press clutch will cause the shaft I to rotate only through a single complete revolution, whereupon it is automatically disengaged.
  • teeth engage the teeth of the gear wheel'5; so that prior to the rotation of the head 9, the spring will be bent as shown in Fig. 5 and the partspositioned relatively to the head 9 and the cam member 12 thereof, illustrated in Fig. 5, wherein it'is clearly indicated that the end wall of the head "9 which meets with the cutaway portion M of the cam, is supplied with the recess 48, also shown in Fig. 9, and into which the terminal'end portion I5 of the spring projects until it is forced out of said recess by rotation of said head 9.
  • the gear wheel5' is rigid with a hub49which is provided with a V-shaped recess 50 in which the V-shaped projection 5
  • the member l9 and other operating parts of the machine are normally disposed in the position shown in Fig. 2.
  • the anti-friction roller2l will havebeen returned tothefposition-in there'cess 24 of the cam 22'shown in Figj and'simultaneously' therewith the head 40 of the clamping member '34 will have 'been'restored to the position shown in Fig. 3.
  • Interchangeable heads 9' are provided for operations on'springs composed of di'fierent gauges of wire.
  • A'machine of the kind specified comprising a longitudinally slotted rota-table coiling head, a manually controlled power actuated mechanism for imparting to said head a predetermined.
  • a spring carrier equipped with means for firmly holding aspring in predetermine'd :position thereof, and in opposed relation "spring clamping member mounted on said carrier, and means on the machine frame disposed 'in the path of said clamping member for throwing the same into engagement with the spring at 'a point contiguous to the 'said head "at the instant of completion of said movement of said fill carrier and so maintaining the same during the period of rotation of said head, and means arranged for cooperation with said carrier for effecting bending of a predetermined length of a terminal portion of the spring during said movement of said carrier to cause said end portion to overlap said first-named, portion and hold the same in engaging relation to said head for effecting coiling of a part of said end portion about said first-named portion of said spring, said lastnamed means cooperating also with said clamp- 7 the beginning of the actuation of said head, a
  • a machine of the kind specified comprising a longitudinally slotted rotatable coiling head, a manually controlled power-actuated mechanism for imparting to said head a predetermined number of complete revolutions at each actuation thereof, a spring carrier equipped with means for firmly holding a spring in predetermined position thereof, and in opposed relation to said slot of said head, means included in said mechanism for moving said carrier toward said head for positioning a predetermined portion of the spring carried thereby in'said slot prior to the beginning of the actuation of said head, a spring clamping member mounted on said carrier, and means on the machine frame disposed in the path of said clamping member for throwing the same into engagement with the spring at a point contiguous to that of overlap of the firstnamed portion of said spring by said terminal end portion thereof and.
  • a machine of the kind specified comprising a coiling head'equipped with radial slot to relatter is at rest, means associated with said carrier for enabling the spring to be mounted upon the latter in a given position, a rotatable cam included in said mechanism and operatively engaged with said carrier for moving the same to a position wherein a predetermined portion of the spring is disposed in said slot prior to beginning and so maintaining the same until completion of rotation of said head, said carrier cooperating with said head to bend a terminal end portion of the spring into overlapping relation to another portion thereof during said movement of said carrier, and a clamping means associated with said carrier for engagement with the lastnamed portion of said spring at substantially the instant of completion of said movement of said carrier.
  • a machine of the kind specified comprising a coiling head equipped with radial slot to receive a portion of a spring about which said head is adapted to rotate, power actuated, manually controlled mechanismfor rotating said head through a predetermined number of revolutions at each actuation thereof, a cam member rigidly mounted upon one end of said head, a self-restoring spring carrier opposed to the slot of said head when the latter is at rest, means associated with said carrier for enablingthe spring to be mounted upon the latter in a.
  • a machine of the kind specified comprising a coiling head equipped with radial slot to receive a portion of a spring about which said head is adapted to rotate, power actuated, manually controlled mechanism for rotating said head through a predetermined number of revolutions at each actuation thereof, a cam member rigidly mounted upon one end of said head, a self-restoring spring carrier opposed to the slot of said head when the latter is at rest, means associated with said carrier for enabling the spring to be mounted upon the latter in a given position, a rotatable cam included in said mechanism and operatively engaged 'with said carrier for moving the same to a posi- .with said head to bend a terminal end portion of the spring into overlapping relation to anotherportion thereof during said movement of said carrier and disposing the same in thepath of said cam member on saidhead for causing the latter to coil the same about the portion of the spring immediately adjacent one end of the part thereof disposed within said slot during iotation of said head, a spring clamping lever mounted onsaid carrier, and a member rigid with'
  • a machine of the kindspecified comprising a coiling head equipped with radial slot to receive a portion of a spring about which said head is adapted to rotate, power actuated, manually controlled mechanism for rotating said head through a predetermined number of revolutions at each actuation thereof, a cam member rigidly mounted upon one end of said head, a, selfrestoring spring carrier opposed to the slot of said head when the latter is at rest, means associated with said carrier for enabling the spring to be mounted upon the latter in a given position, a rotatable cam included in said mechanism and operatively engaged with said carrier for moving the same toa position wherein a predetermined portion of the spring is disposed in said slot prior to beginning and so maintaining the same until completion of rotation of said head, saidcarrier cooperating with said head to bend aterminal end portion of the spring into overlapping relation to another portion thereof during said movement of said carrier and disposing the samesin the path of said cam member on said headfor causing the latter to coil the same about the portion of the spring immediately adjacent .
  • a rotatable coiling head adapted to receive and rotate about a portion of a spring and equipped with means for engaging a terminal end portion of said spring disposed in overlapped relation, another portion thereof for coiling said terminal portion about the last-named portion, a carrier for the spring equipped with shoulders opposed to said head for engaging said respective portions of said spring, an end of one of said shoulders being opposed substantially to said means on said head and fromwhich a terminal end portion of said spring is adapted to project, a stop arranged for cooperation with said end of said lastnamed shoulder for determining the length of terminal end portion of the the spring adapted to be coiled about the coil thereof engaged with r the other of said shoulders, power actuated mechanism for causing said carrier to be moved to project the first-named portion of the spring into said head, the latter cooperating with said carrier to effect bending of the said terminal end' portion of said spring into overlapping relation to the second-named coil of said spring preceding the beginning-of rotationofsaid head, said mechanismdn
  • a machine of the kind specified comprising a carrierforaspring equipped with a 'pair of shoulders disposed at different elevations and spaced-fromeach other,- the lower of saidshoulders adapted-to engage a portion of a terminal coil of the spring spaced-from an extremity thereof "and-the higher shoulder adapted to engage a portion of the next-adjacent coilof the spring,-a longitudinally 'slotted rotatable coiling head opposed to and adapted to receive and rotate about a predetermined portion of the spring disposed beyond said shoulder of said carrier.
  • Aspring knotting machine comprising a rotatablecoiling head "equipped with a, radial slot adapted to receive a portion-of a spring about which; said head is adapted to rotate, a
  • spring. carrier disposed at one side of said head and spaced forwardly of the slot of; the latter, a pair of shoulders on said carrier adapted to engage aportion .of a terminal coil of said spring and a portion of the next adjacent coil opposed thereto, another. portion of said lastnamed, coil opposed tosaiduhead being.
  • a spring knotting machine comprising a rotatable coiling head equipped with a radial slot adapted to receive a portion of a spring about which said head is adapted to rotate, a spring carrier disposed at one side of said head and spaced forwardly of the slot of the latter, a pair of shoulders on said carrier adapted to engage a portion of a terminal coil of said spring the position wherein the said bending operation thereto, another portion of said last-named coil opposed to said head being adapted to be projected into the slot of said head, means at one end of said head adapted to cooperate with one end of v the shoulder of the carrier engaged with the first-named portion of the spring to effect bending of the adjacent terminal end portion of spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a stop disposed for engagement with the extremity of said terminal portion of the spring for determining the length thereof, a shoulder at said end of said head equipped with said first-named means for engaging said bent terminal end
  • a spring knotting machine comprising a rotatable coiling head equipped with a radial slot adapted to receive a portion of a spring about which said head is adapted to rotate, a spring carrier disposed at one side of said head and spaced forwardly of the slot of the latter, a pair of shoulders on said carrier adapted to engage a portion of a terminal coil of said spring and a portion of the next adjacent coil opposed thereto, another portion of said last-named coil opposed to said head being adapted to be projected into the slot of said head, means at one end of said head adapted to cooperate with one end of the shoulder of the carrier engaged with 'the first-named portion of the spring to efiect bendingof the adjacent terminal end portion of spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a shoulder at said end of said head equipped with said first-named means for engaging said bent terminal end of the spring as said head rotates for coiling the same about the secend-named
  • a spring knotting machine comprising a rotatable coiling head equipped with a radial slot adapted to receive a portion of a spring about which said head is adapted to rotate, a spring carrier disposed at one side of said head and spaced forwardly of the slot of the latter, a pair of shoulders on said carrier adapted to engage a portion of a terminal coil of said spring and a portion of the next adjacent coil opposed V thereto, another portion of said last-named coil opposed to said head being adapted to be projected into the slot of said head, means at one end of said head adapted to cooperate with one end of the shoulder of the carrier engaged with the first-named portion of the spring to effect bending of' the adjacent terminal end portion of said spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a stop disposed for engagement with the extremity of said terminal portion of the spring for predetermining the length thereof, a shoulder at said'end of said head equipped with said first-named means for engaging said

Description

Dec; 27, 1938.
F. R. ZIMMERMAN.
SPRING KNOTTING MACHINE Filed Sept. 17, 1937 5 Sheets-Sheet 1 I HI Dec. 27, 1938. F. R. ZIMMERMAN 2,141,588
SPRING KNOT'I'ING MAGH INE 5 Sheets-Sheet 2 Filed Sept. 17, 1957 I IL Dec. 27, 1938. F. R. ZIMMERMAN SPRING KNOTTING MACHINE,
F'il edSept. 17, 1937 5 SheetSSheet 3 Dec. 27, 1938. F. RLZIMMERMAN SPRING KNQTTING MACHINE Filed Sept 17, 1937 5 Sheets-Sheet 4 1938- F. R. ZIMMERMAN SPRING KNOTTING MACHIlfJE Filed Sept. 17, 1957 5 Sheets-Sheet 5 Patented Dec. 27, 1938 UNITED STATES PATENT OFFICE 7 2,141,588 'sPmNG KNOTTING M AC HINE Fred R. Zimmerman, Chicago, 111., assignor to Nachman Springfilled Corporation, Chicago,
111., a corporation of Illinois I Application September 17, 19 37, SerialNo.164,330
The invention has for its main object to provide a simple and efficient machine for knotting upholsteryv springs of different, sizes and composed of wire of gauges commensurate with the size and load carrying capacity of the spring.
Upholstery springs of various types such as hour-glass, cone and cylindrical, are delivered from conventional machines known. as coilers with their terminal end portions spaced from the nearest points disposed substantially radially of the extremities of said springs. To coil said end portions about the substantially radially opposed portions of said springs has heretofore been accomplished by first bending -said terminal end portions inwardly so that a predetermined part of each of said end portions'became disposed .in overlapped. relation to the portion of the body of the spring to' provide a projection of predetermined length extending inwardly ofthe part overlapped thereby, said length being determined by the number of. turns vor coils desired to embrace the overlapped portion of. the spring. These operations preceded the final knotting operation performedgenerally by a pedal operated machine, both operations at each end of. t e spring being relatively slow and, therefore, costly.
One of the objects of the present invention is to provide a knotting machine which performs each bending operation immediately preceding the knotting operation, so. thatboth said operations are performed substantially simultaneously.
A suitable embodimentof the invention is illustrated in the accompanying drawings, where- Fig. 1 is a front elevation partly in section of a machine constructed in accordance with the invention.
. Fig. 2 is a vertical sectional view of the machine taken on theline.2-2 of Fig.1.
. Fig. 3 is a side elevation of the machine, also partly in section. b r
Fig. 4 is a view similar to Fig. 3 showing the operating parts of the machine in another position.
, Fig. 5 is a fragmentary sectional viewon an enlarged scale, talgen on thejline 55 of Fig. 4.
Fig, .6 is a fragmentary top plan view of the machine. v e V Fig. '7 is a fragmentary perspectiveview of an upholstery spring adapted to be knotted by the machine, showing a terminal end portion bent to overlap another portion thereof preparatory to effecting knotting'of the spring.
.Fig. 8 is a view similar to Fig. 7 showing the completion of the knotting operation.
d Fig. 9 is a perspective view of the coiling or knotting head of the machine.
. Fig. 10 is a detailperspective view on an enlarged scale showing the spring carrying element of the machine. V A
. The machine comprises a suitable frame equipped with bearings for actuating shaft l thereof, which carries a loose pulley 2.
Rigidly mounted upon the shaft I is a clutch member 3 constituting an element of a conventional punch-press clutch which will not be described because well known to those skilled in the art. The engagement of the member. 3 with the pulley. 2 is manually controlled by means of a manually operable lever 55 (Fig. 2) which controls. the actuation of'said shaft l at the will of the operator and is actuated by a rod 56. i
7 Rigid with the shaft l is a spur gear wheel 4 which, as shown in Fig. 2, is a segmental gear of a well-known type which meshes, during a part .of its revolution, with the spur gear wheel 5 on a countershaft 6. Said spur gear wheel 5 meshes with a spur gear wheel 1 on a second countershaft 8 and the latter, in turn, meshes with the spur gear teeth of the coiling head 9, said spur gearteeth ll] of the head 9 being shown in detail in Fig. 9 and being shown also in dotted lines in Fig. 4. The gear ratio between said spur gear wheel land the said coiling head 9 is such that at each complete revolution of said wheel other gear wheels for increasing or reducing the number of completelrevolutions through which the head 9 is rotated at each actuation of the wheel 4.
The coiling head 9 is equipped with a longitu- Tdinal slot H extending throughout its length and which is radially disposed, the innermost or end wall of said slot being semi-cylindrical and concentric with the axis of rotation of said head 9.
Said head is equipped at one end with what may be termed a cam member l2, also shown in Fig. 9, which is provided with a normally horizontally disposed top face l3 aligned with the diametric plane of the head 9 which is coincidental with the said slot ll thereof. Said face l3 terminates at the innermost end of the slot H at one end and at the circumferential face of the said head diametrically opposite the mouth of the slot I I.
The said cam member I2 has an arcuate face which is flush with the cylindrical face of the head 9, the cut-away portion [4 of said cam l, the head 9 isrotated through a predetermined the ends of the member i9 is an anti-friction" roller 2| which is maintained normally engaged 1 with a cam 22 rigid with the shaft I, by means of a tension spring 23. f 4
The cam 22 is equipped with a recess 24 and with circumferential or cylindrical face, the bot-' tom wall of said recess being concentric with the axis of rotation of said cam and the end walls of said recess being flaring and substantially ogee-curved, so that the roller 2! may ride easily out of the recess upon the circumferential face of the cam, and vice-versa, as the latter is rotated.
Mounted upon the upperand outermost end portion of the member I9 is a springvcarrierplate 25, shown in detail in Fig. 10, which is disposed normally in forward position and'to one side of the head '9 when the latter is at rest, as shown in Fig. 3. Said plate 25 is equipped with a raised portion 26 having parallel edges, one of which is flush with one side edge of saidplate 25 and has its other edge parallel with and spaced from the other side edge of said plate 25. The end portion of the part 26 of the plate 25 has an arcuate front edge spaced from the front edge of the plate 25 and an arcuate shoulder 28 spaced from the arcuate edge 26a. The plate 25 is equipped at its forward left hand corner, as shown in Fig. 10,'with a'projection 29 having an arcuate face which is opposed to the left hand forward corner of the arcuate edge 21. 1 j H As shown in Fig. 6 the terminal end portion of a-terminal coil 30 of a spring I5 is disposed in contact with the arcuate surface 2! of said part- 26 of the plate 25, and is engaged also by the projection 29, whereas, the next adjacent convolution I! of the spring is engaged, in part, by the arcuate shoulder 28. 7
Mounted upon the frame of the machine is an adjustable stop 3l against which the extremity of the terminal coil of thespring I6 is caused to abut in order to position the spring as desired in the machine preparatory to effecting knotting thereof. An adjustable stop 32 disposed upon the portion I 9a of member i9 behindthe plate 25, engages a portion'of the terminal coil of the spring [6 which is substantially diametricallyopposed to the portion of said spring which is engaged with the arcuate shoulder 28.
Pivotally mounted between its ends upon a s ud shaft 33 carried by the member l 9 at a point substantially vertically aligned with the stud shaft 20, is a spring-clamping lever 34, one end of which is engaged with the tension spring 35 for maintaining said lever normally in the position shown in Fig. 3.
The machine'frame is equipped with an. upwardly projecting head 33 which is equipped with the bearing for the opposite end portions of the head 9, the said respective end portions of the latter disposed at opposite sides of the spur gear teeth It] being cylindrical and housed in said bearings. The latter are equipped with slots which normally are aligned with the slot l l of said headS.
Mounted in said head 36'is an adjustable shaft a 31 which carries an eccentric 38 disposed in the path of the substantially ogee-curved formation 39 of one end portion of the head Ml of the lever 34, said head 40 being provided with a recess 4! which is adapted to receive the portion of the convolution I! of the spring I8, shown in Fig. 6,
immediately adjacent one end of the said head 9,
saidend portion'or head 40 of said lever34 being disposed angularly to the body of said lever as shown in Fig. 6.
7 The said shaft 31 is equipped at its other end Witha nut 42 by means of which it is clamped against rotation after effecting adjustment of the position of said. eccentric 38 relatively to the head 9 to cause said: lever 33 to firmly engage a portion I! of the spring l6 engaged with the shoulder 28 to clamp said spring against movement during the coiling operation, said eccentric being shown imposition wherein the head 4!) of the lever 34 is adapted to engage a spring 16 composed of wire of heaviest gauge which the machine is capable of operating upon. Obviously, the said eccentric 38 will be/moved from the position shown in Fig. 3 to another position, depending upon the gauge of wire of the spring which is being operated upon.
Obviously, the plate 25 is interchangeable with other similar plates wherein the arcuate shoulder 23 is of'less height in each instancethan the portion I? of the spring adapted to be engaged therewith, so that the said head 40 of the clamping lever 34 may engage said portion of the. spring disposed 'in engagement with said shoulder to clamp the same firmly against. the surface between the shoulders 28 and 21.
' It will be obvious that as soon as the rotation of the cam 22 begins, the anti-friction roller 2! will ride over the adjacent endwall of the recess .24 and upon the circumferential face of said cam.
This will cause the said member 19 to swing to the position shown in Fig. 4 whereby the portion of the terminal coil .of the spring opposed to the mouth of the slot H of the head 9 will be moved into said slot and practically in contact with the innermost wall of the latter. At the same instant that this occurs, the'said head 40 of the clamping lever 34 will be moved by contact with the eccentric 38 into the position shown in Fig. 4 wherein it clamps against movement the portion of the convolution ll of the spring next adjacent 'to that about which the terminal end portion E5 of the latter is to be coiled during the succeeding coiling operation, which may be said to begin almost instantly after the beginning of rotation of said cam 22.
When the parts above described are disposed in the position shown in Fig. 4, the terminal coil .of the spring 16 will have its end portion l5 disposed in the position shown in Fig. 5 and the convolution I! of said spring will overlie said terminal portion it between the ends of the latter and will be maintainedfirmly in said position by means of said head 43 of the clamping lever 34.
During movement of the said plate 25 carried by the said member IS, the terminal end portion 15 of the spring I 6 will be engaged in the recess 58 in the left hand end wall 33 of the head 9 between the slot H and the cut-away portion M of the cam member 12 of said head and will be bent from the position indicated in dotted lines at M in Fig. 7 to the full line position of Fig. 5.
The punch-press clutch will cause the shaft I to rotate only through a single complete revolution, whereupon it is automatically disengaged. To prevent the same from rotating more than revolutionand before its, teeth engage the teeth of the gear wheel'5; so that prior to the rotation of the head 9, the spring will be bent as shown in Fig. 5 and the partspositioned relatively to the head 9 and the cam member 12 thereof, illustrated in Fig. 5, wherein it'is clearly indicated that the end wall of the head "9 which meets with the cutaway portion M of the cam, is supplied with the recess 48, also shown in Fig. 9, and into which the terminal'end portion I5 of the spring projects until it is forced out of said recess by rotation of said head 9.
The gear wheel5'is rigid with a hub49which is provided with a V-shaped recess 50 in which the V-shaped projection 5| of an arm 52 engages as shown'in Fig. 2, said arm being pivotally secured at its lower end to a stud-shaft 53 and held in engagement with'the said hub by means of tension spring 54.
Obviously, following release of the teeth ofthe gear wheel 5 from the teeth of .the gear wheel 4, the rotation of said wheel 5 will be stopped by means of the said lever "52, so that substantially the final quarter revolution of the shaft I will be effected without actuating the gear wheel 5.
It is believed that the operation of the machine will'be fully and readily understood from the foregoing description, but is briefly reviewed as follows:
The member l9 and other operating parts of the machine are normally disposed in the position shown in Fig. 2.
The operator then places one end of 'the 'upholstery spring upon the plate 25 in the position shown in Fig. 6 with the extremity of a terminal coil of saidspring in contact with the stop 3| and with a portion of said'spring engaged with the stop 32. A portion of a convolution I1 of the spring is engaged with the 'arcuate shoulder 28;
The operator then 'actuates the punch press clutch control lever to cause the shaft l'to rotate through a complete revolution and thereby causes the cam 22 to throw the member I9, which carries the plate 25, to'the position shown in Fig, 4.
Duringthis slightly upward swing of said member IS, the extremity of the spring I6 is disengaged from the stop 3! and said spring I6 is swung so that the portion of the coil I! imvmediately beyond the right hand end of the varouate shoulder 21 is moved into the slot H of adjacent the point at which it is overlapped by said end portion !5. This projecting of the terminal coil into the slot H of the head 9 occurs before the head 9 begins to rotate, it "being obvious from Fig. 2 that the rotation of the head 9 will begin only when the teeth of the gear wheel 4 are thrown into mesh with the teeth of the gear Wheel '5.
Rotation of the head 9 causes the cutawayportion it of the cam member "I2, integral with 'the said head, to coil-theterminal end portion "I 5 of the spr n about fthe "centailiitio'n 'I'I thereofto complete the knotting "operatio"n at one end of the spring. V i
As soonasthe' shaftihas oompletedits revolution, the anti-friction roller2l will havebeen returned tothefposition-in there'cess 24 of the cam 22'shown in Figj and'simultaneously' therewith the head 40 of the clamping member '34 will have 'been'restored to the position shown in Fig. 3.
The spring isthen removed-and itsposition reversed or another spring inserted in place thereof, "whereupon theaioresaid'operation is repeated.
Interchangeable heads 9' are provided for operations on'springs composed of di'fierent gauges of wire. Y
Theportion of theheadfl midway between its ends "is directly opposed to' the longitudinal axis of thespring to be operated fupon'and the position of the'plate 25 usedwith eachhead '9 employedis so spaced from the left hand end of the head 9as to cause theterminal end 15 of the spring tobe bent as shown inFig. 5 when'said plateis moved to thepos'ition therein shown.
I claim as my invention:
1. :A machine of thekind specifiedcomprising a longitudinally'slotted rotatablecoiling head, a manually controlled power actuated mechanism for imparting to saidheada predetermined number cf complete revolutions at each actuation thereof a spring carrier-equipped with means for firmlyhol'ding a spring in predetermined position th ereon,'-a-nd in opposed relation to said slot of said head, m'eansincliidedin said mechanism 9 for moving said carrier toward said head for positioning a predeterminedportionbf the spring carried thereby in "said'slot prior to thebeginning of the actuation of said head, a spring clamping member mounted on'said carrier, and means on the machine frame disposed in the pathoffsaid olampingmember forthrowing the sameinto engagement with the spring atthe instantof completion of said movement of said carrier and so" maintaining the same during the period of rotationof said he'adfand means ar ranged for cooperation'with'saidc'arrierfor effecting bendingof a predetermined length or a terminal portion of the spring during said movement of said oarrie'r'to causesaid end portion to overlap said first-named portion and hold the same in engaging'relation to said head for effect ing coiling of a part ofsaid. end portion about said first-'namedportionpf said spring, said lastnar'ned means'cooperating also with saidclamp- 'ing'mean's.
2. A'machine of the kind specified'comprising a longitudinally slotted rota-table coiling head, a manually controlled power actuated mechanism for imparting to said head a predetermined.
number of complete revolutions at each actuation thereof, a spring carrier equipped with means for firmly holding aspring in predetermine'd :position thereof, and in opposed relation "spring clamping member mounted on said carrier, and means on the machine frame disposed 'in the path of said clamping member for throwing the same into engagement with the spring at 'a point contiguous to the 'said head "at the instant of completion of said movement of said fill carrier and so maintaining the same during the period of rotation of said head, and means arranged for cooperation with said carrier for effecting bending of a predetermined length of a terminal portion of the spring during said movement of said carrier to cause said end portion to overlap said first-named, portion and hold the same in engaging relation to said head for effecting coiling of a part of said end portion about said first-named portion of said spring, said lastnamed means cooperating also with said clamp- 7 the beginning of the actuation of said head, a
spring clamping member mounted on said carrier, and means on the machine frame disposed in the path of said clamping member for throwing the same into engagement with the spring at a point contiguous to that of overlap of the firstnamed portion of said spring by said terminal end portion thereof at the instant of completion of said movement of said carrier and so maintaining the same during the period of rotation of said head, and meansarrang-ed for cooperation with said carrier for effecting bending of a predetermined length of a terminal portion of the spring during said movement of said carrier to cause said end portion to overlap said firstnamed portion and hold the same in engaging relation to said head for efiecting coiling of a part of said end portion about said first-named portion of said spring, said lastenamed means cooperating also with said clamping member.
4. A machine of the kind specified comprising a longitudinally slotted rotatable coiling head, a manually controlled power-actuated mechanism for imparting to said head a predetermined number of complete revolutions at each actuation thereof, a spring carrier equipped with means for firmly holding a spring in predetermined position thereof, and in opposed relation to said slot of said head, means included in said mechanism for moving said carrier toward said head for positioning a predetermined portion of the spring carried thereby in'said slot prior to the beginning of the actuation of said head, a spring clamping member mounted on said carrier, and means on the machine frame disposed in the path of said clamping member for throwing the same into engagement with the spring at a point contiguous to that of overlap of the firstnamed portion of said spring by said terminal end portion thereof and. at a point contiguous to the portion of the head engaging said overlapping end portion during rotation of said head at the instant of completion of said movement of said carrier and so maintaining the same during the period of rotation of said head, and means arranged for cooperation with said carrier for effecting bending of a predetermined length of a terminal portion of the spring during said movement of said carrier to cause said end portion to overlap said first-named portion and hold the same in engaging relation to said head for effecting coiling of a part of said end portion about said first-named portion of said spring, said last-named means cooperating also with said clamping member. 7
5. A machine of the kind specified comprising a coiling head'equipped with radial slot to relatter is at rest, means associated with said carrier for enabling the spring to be mounted upon the latter in a given position, a rotatable cam included in said mechanism and operatively engaged with said carrier for moving the same to a position wherein a predetermined portion of the spring is disposed in said slot prior to beginning and so maintaining the same until completion of rotation of said head, said carrier cooperating with said head to bend a terminal end portion of the spring into overlapping relation to another portion thereof during said movement of said carrier, and a clamping means associated with said carrier for engagement with the lastnamed portion of said spring at substantially the instant of completion of said movement of said carrier.
6. A machine of the kind specified comprising a coiling head equipped with radial slot to receive a portion of a spring about which said head is adapted to rotate, power actuated, manually controlled mechanismfor rotating said head through a predetermined number of revolutions at each actuation thereof, a cam member rigidly mounted upon one end of said head, a self-restoring spring carrier opposed to the slot of said head when the latter is at rest, means associated with said carrier for enablingthe spring to be mounted upon the latter in a. given position, a rotatable camincluded in said mechanism and operatively engaged with said carrier for moving the same to a positioniwherein a predetermined portion of the spring is'disposed in said slot prior to beginning and so maintaining the same until completion of rotation ofsaid head, said carrier 7 cooperating with said head to bend a terminal end portion of the spring into overlapping relation to another portion thereof during said movement of said carrier and disposing the same in the path of said cam member on said head for causing the latter to coil the same about the portion of the spring immediately adjacent one end of the part thereof disposed within said slot during rotation of said head, and a clamping means associated with said carrier for engagement with the last-namedportion of said spring at substantially the instant of completion of said movement of said carrier.
7. A machine of the kind specified comprising a coiling head equipped with radial slot to receive a portion of a spring about which said head is adapted to rotate, power actuated, manually controlled mechanism for rotating said head through a predetermined number of revolutions at each actuation thereof, a cam member rigidly mounted upon one end of said head, a self-restoring spring carrier opposed to the slot of said head when the latter is at rest, means associated with said carrier for enabling the spring to be mounted upon the latter in a given position, a rotatable cam included in said mechanism and operatively engaged 'with said carrier for moving the same to a posi- .with said head to bend a terminal end portion of the spring into overlapping relation to anotherportion thereof during said movement of said carrier and disposing the same in thepath of said cam member on saidhead for causing the latter to coil the same about the portion of the spring immediately adjacent one end of the part thereof disposed within said slot during iotation of said head, a spring clamping lever mounted onsaid carrier, and a member rigid with'the machineframe and disposed in the path of said lever for throwing the latter into positionto engage the last-named portion of the spring upon the vcarrier against movement during rotation of said head. i
8. A machine of the kindspecified comprising a coiling head equipped with radial slot to receive a portion of a spring about which said head is adapted to rotate, power actuated, manually controlled mechanism for rotating said head through a predetermined number of revolutions at each actuation thereof, a cam member rigidly mounted upon one end of said head, a, selfrestoring spring carrier opposed to the slot of said head when the latter is at rest, means associated with said carrier for enabling the spring to be mounted upon the latter in a given position, a rotatable cam included in said mechanism and operatively engaged with said carrier for moving the same toa position wherein a predetermined portion of the spring is disposed in said slot prior to beginning and so maintaining the same until completion of rotation of said head, saidcarrier cooperating with said head to bend aterminal end portion of the spring into overlapping relation to another portion thereof during said movement of said carrier and disposing the samesin the path of said cam member on said headfor causing the latter to coil the same about the portion of the spring immediately adjacent .one end of the part thereof disposed within said slot during rotation of said head a spring clamping lever mounted on said carrier, and a member rigid with the machine frame and an adjustable member rigid with the machine frame and disposed in the path of said lever for throwing the latter into position to engage the last-named portion of the spring upon the carrier against movement during rotation of said head.
9. In a machine of the kind specified, a rotatable coiling head adapted to receive and rotate about a portion of a spring and equipped with means for engaging a terminal end portion of said spring disposed in overlapped relation, another portion thereof for coiling said terminal portion about the last-named portion, a carrier for the spring equipped with shoulders opposed to said head for engaging said respective portions of said spring, an end of one of said shoulders being opposed substantially to said means on said head and fromwhich a terminal end portion of said spring is adapted to project, a stop arranged for cooperation with said end of said lastnamed shoulder for determining the length of terminal end portion of the the spring adapted to be coiled about the coil thereof engaged with r the other of said shoulders, power actuated mechanism for causing said carrier to be moved to project the first-named portion of the spring into said head, the latter cooperating with said carrier to effect bending of the said terminal end' portion of said spring into overlapping relation to the second-named coil of said spring preceding the beginning-of rotationofsaid head, said mechanismdncluding means for eifecting rotation of said 1head-throughout a predetermined number of complete revolutions'during which said firstnamed'means on saidhead engage andcoil said terminal portionof said spring about the portion of the latter overlapped "thereby.
10. A machine of the kind specified comprising a carrierforaspring equipped with a 'pair of shoulders disposed at different elevations and spaced-fromeach other,- the lower of saidshoulders adapted-to engage a portion of a terminal coil of the spring spaced-from an extremity thereof "and-the higher shoulder adapted to engage a portion of the next-adjacent coilof the spring,-a longitudinally 'slotted rotatable coiling head opposed to and adapted to receive and rotate about a predetermined portion of the spring disposed beyond said shoulder of said carrier. means on'said-head cooperating'with one end of the lower shoulder for bending theportion of'the spring disposed between the said extremity thereof and the portion engaged with said lower shoulder as said carrier ismoved to project said 1 predetermined portion of said spring into'said head, means on one endof said head adapted-to engage the bent terminal end thereof as said head is' rotated for coiling the latter about a portion of said predeterminedportionof the spring about which said head is rotatable, and power actuated means formoving said carrier in the directionyfor projecting and bending the respective portions of the spring for engagement 'by said head and therafter effecting rotation of said head, thereby to effect knotting of the spring,
311; Aspring knotting machine comprising a rotatablecoiling head "equipped with a, radial slot adapted to receive a portion-of a spring about which; said head is adapted to rotate, a
spring. carrier. disposed at one side of said head and spaced forwardly of the slot of; the latter, a pair of shoulders on said carrier adapted to engage aportion .of a terminal coil of said spring and a portion of the next adjacent coil opposed thereto, another. portion of said lastnamed, coil opposed tosaiduhead being. adapted 'to' be'projected into the slot of said head means at one end ofsaid head adapted to cooperate with one end of the shoulder of the carrier engaged with the first-named portion of the spring to effect bending of the adjacent terminal end portion of spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a shoulder at said end of said head equipped with said first-named means for engaging said bent terminal end of the spring as said head rotates for coiling the same about the second-named coil of the spring, and power actuated mechanism for moving said carrier to is completed and said second-named portion of said spring is disposed in said slot and thereafter effecting rotation of said head to complete the knotting operation.
12. A spring knotting machine comprising a rotatable coiling head equipped with a radial slot adapted to receive a portion of a spring about which said head is adapted to rotate, a spring carrier disposed at one side of said head and spaced forwardly of the slot of the latter, a pair of shoulders on said carrier adapted to engage a portion of a terminal coil of said spring the position wherein the said bending operation thereto, another portion of said last-named coil opposed to said head being adapted to be projected into the slot of said head, means at one end of said head adapted to cooperate with one end of v the shoulder of the carrier engaged with the first-named portion of the spring to effect bending of the adjacent terminal end portion of spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a stop disposed for engagement with the extremity of said terminal portion of the spring for determining the length thereof, a shoulder at said end of said head equipped with said first-named means for engaging said bent terminal end of the spring as said head rotates for coiling the same about the secondnamed coil of the spring, and power actuated mechanism for moving said carrier to the position wherein the said bending operation is completed and said second-named portion of said spring is disposed in said slot and thereafter efiecting rotation of said head to complete the knotting operation. V
13. A spring knotting machine comprising a rotatable coiling head equipped with a radial slot adapted to receive a portion of a spring about which said head is adapted to rotate, a spring carrier disposed at one side of said head and spaced forwardly of the slot of the latter, a pair of shoulders on said carrier adapted to engage a portion of a terminal coil of said spring and a portion of the next adjacent coil opposed thereto, another portion of said last-named coil opposed to said head being adapted to be projected into the slot of said head, means at one end of said head adapted to cooperate with one end of the shoulder of the carrier engaged with 'the first-named portion of the spring to efiect bendingof the adjacent terminal end portion of spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a shoulder at said end of said head equipped with said first-named means for engaging said bent terminal end of the spring as said head rotates for coiling the same about the secend-named coil of the spring, automatic spring clamping means on said carrier for maintaining the second-named portion of said spring engaged with said carrier during rotation of said head, and power actuated mechanism for moving said carrier to the position'wherein the said bending operation is completed and said second-named portion of said spring 'is disposed in said slot and thereafter effecting rotation of said head to complete the knotting operation.
14. A spring knotting machine comprising a rotatable coiling head equipped with a radial slot adapted to receive a portion of a spring about which said head is adapted to rotate, a spring carrier disposed at one side of said head and spaced forwardly of the slot of the latter, a pair of shoulders on said carrier adapted to engage a portion of a terminal coil of said spring and a portion of the next adjacent coil opposed V thereto, another portion of said last-named coil opposed to said head being adapted to be projected into the slot of said head, means at one end of said head adapted to cooperate with one end of the shoulder of the carrier engaged with the first-named portion of the spring to effect bending of' the adjacent terminal end portion of said spring into underlapping relation to the second-named portion of said spring as said carrier is moved to project the latter into the slot of said head, a stop disposed for engagement with the extremity of said terminal portion of the spring for predetermining the length thereof, a shoulder at said'end of said head equipped with said first-named means for engaging said ond-named portion of said springis disposed in said. slot and thereafter efiecting rotation of 45 said head to complete the knotting operation.
FRED R. ZIMMERMAN.
US164330A 1937-09-17 1937-09-17 Spring knotting machine Expired - Lifetime US2141588A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2836205A (en) * 1946-09-30 1958-05-27 Wunderlich Spring Machinery Co Coil spring producing machine
DE1100573B (en) * 1954-07-03 1961-03-02 Spuehl Ag Machine that works with an upholstery spring coiling machine to knot the wire ends of the upholstery springs with their end coils
US3338273A (en) * 1965-01-18 1967-08-29 United Mattress Machinery Comp Knotting head

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2836205A (en) * 1946-09-30 1958-05-27 Wunderlich Spring Machinery Co Coil spring producing machine
DE1100573B (en) * 1954-07-03 1961-03-02 Spuehl Ag Machine that works with an upholstery spring coiling machine to knot the wire ends of the upholstery springs with their end coils
US3338273A (en) * 1965-01-18 1967-08-29 United Mattress Machinery Comp Knotting head

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