US3805579A

US3805579A - Wire forming method

Info

Publication number: US3805579A
Application number: US00248895A
Authority: US
Inventors: R Calvert; D Scott
Original assignee: Mead Corp
Current assignee: Mead Corp
Priority date: 1970-05-15
Filing date: 1972-05-01
Publication date: 1974-04-23
Anticipated expiration: 1991-04-23

Abstract

A wire forming machine and method imparts an undulatory configuration to a strand of wire and includes a pair of wheels disposed alongside each other and rotatable about angularly disposed axes. Pins are disposed radially about the peripheries of both wheels. The angularly disposed wheel axes result in a variation in the spacing between the pins of one wheel and the adjacent pins on the other wheel so that wire looped about the pins is alternately tightened and loosened. Fixed wire removal and holding means are arranged so as to engage the wire at points of minimum and maximum lateral spacing respectively, an oscillatable releasing finger engages the wire following the looping thereof about one pin to release the wire from rotatable looping means, and a reciprocable plunger is arranged to engage another part of the wire to aid in securing the wire about a pin on one of the wheels.

Description

United States Patent [191 Calvert et al.

[ WIRE FORMING METHOD [75] Inventors: Rodney K. Calvert, Dunwoody; Dale K. Scott, .lonesboro, both of Ga.

[73] Assignee: The Mead Corporation, Dayton,

Ohio

22 Filed: May 1, 1972 211 App]. No.: 248,895

Related U.S. Application Data [62] Division of Ser. No. 37,631, May 15, 1970.

[52] U.S. Cl 72/378, 72/190, 72/385, 140/105 [51] Int. Cl B2lf 1/04, B2ld 13/00 [58] Field ofSearch ..140/105;72/190, 213.5 1.12. .9; .19. 8

[56] References Cited UNITED STATES PATENTS 3,199,175 8/1965 Wogerbauer 140/105 3,691,808 9/1972 Calvert et a1. 140/105 2,963,048 12/1960 Smith 140/105 1,922,270 8/1933 Southwell et a1. 140/112 2,334,671 11/1943 Gibbons 72/D1G. 16 3,556,166 l/197l Whitney 140/105 Primary Examiner-Charles W. Lanham Assistant Examiner-M. J. Keenan Attorney, Agent, or Firm-Walter M. Rodgers [5 7] ABSTRACT A wire forming machine and method imparts an undulatory configuration to a strand of wire and includes a pair of wheels disposed alongside each other and rotatable about angularly disposed axes. Pins are disposed radially about the peripheries of both wheels. The angularly disposed wheel axes result in a variation in the spacing between the pins of one wheel and the adjacent pins on the other wheel so that wire looped about the pins is alternately tightened and loosened. Fixed wire removal and holding means are arranged so as to engage the wire at points of minimum and maximum lateral spacing respectively, an oscillatable releasing finger engages the wire following the looping thereof about one pin to release the wire from rotatable looping means, and a reciprocable plunger is arranged to engage another part of the wire to aid in securing the wire about a pin on one of the wheels.

3 Claims, 9 Drawing Figures PATENTEDAFR 23 1914 SHEET 1 UF 3 NOE PATENTEB APR 2 3 1974 SHEET 2 [1F 3 FIG.

PATENTEDAPR23 m4 3805579 SHEET 3 [1F 3 FIG. 9

WIRE FORMING METHOD This is a division of application Ser. No. 37,631 filed May 15, I970.

Known machines for imparting an undulatory configuration to a strand of wire conventionally utilize the pair of serrated complementary dies for engaging the wire and bending it into the desired configuration. Such devices are necessarily reciprocable in nature and hence are characterized by high inertia and inherent low operating speed. Such known die devices are not only expensive to build but require a substantial maintenance effort if a satisfactory product is to be formed.

According to this invention reciprocable parts are eliminated and rotatable elements are used instead. More specifically, a pair of wheels disposed alongside each other are rotatably mounted on axes which are angularly disposed so that a plurality of pins disposed about the peripheries of both wheels are caused to occupy spaced relationships which continuously vary throughout each revolution of the wheels. This space variation allows rapid formation of loops of wire about the pins followed by a tightening of the loops due to increased spacing between a particular pin on one wheel and the adjacent pin on the other wheel. Thus a permanent set is imparted to the wire according to a feature of the invention. Various mechanisms for securing the wire in place on the wheels and for removing the wire are provided in accordance with specific features of the invention.

For a better understanding of the invention, reference may be had to the following detailed description taken in conjunction with the accompanying drawings in which FIG. I is an overall front view of a machine constructed according to the invention;

FIG. 2 is a view of a strand of wire formed into a particular configuration by the invention;

FIG. 3 is a view of a formed portion of wire such as is shown in FIG. 2 after a subsequent bending operation has been imparted thereto;

FIG. 4 is an end view of the wire shown in FIG. 3;

FIG. 5 is a plan view of the left-hand end of the machine depicted in FIG. I and which is constructed according to the invention;

FIG. 6 is an enlarged perspective view of certain principal components of the invention as shown in FIGS. I and 5;

FIG. 7 is an enlarged view taken along the line 7-7 indicated in FIG. 5 but showing only the central rotatable looping device formed according to the invention;

FIG. 8 is an enlarged plan view of the left-hand portion of FIG. 5 and which shows certain levers for operating the holding and releasing means of this invention; and

FIG. 9 is a cross-sectional view taken along the line designated 9-9 in FIG. 5.

With reference to the drawings, the numerals l, 2, 3 and 4 designate vertically disposed upright support elements interconnected at their lower ends by a horizontal base member designated by the numeral 5.

Horizontal cross beams

6 and 7 are mounted atop the pedestals l, 2, 3 and 4. Of course corresponding support members such as l-7 are disposed on the opposite side of the machine and together constitute a frame structure for supporting the mechanism.

Generally speaking, a reel of wire 8 rotated by means of a rotatable cone 9 to feed the wire W into the machine for subsequent forming operations. Radial arm 10 facilitates the feeding of wire W and a rotatable roller ll aids in supporting the reel 8. Preferably a plurality of rollers 11 are utilized although only one such device appears in FIG. 1.

The strand of wire W is fed along a fixed feeding tract 12 into the wire looping mechanism generally designated by the numeral 13 which imparts a configuration in the wire W wherein the portions of the undulation extending between

pins

20 and 21 have spaced parallel sides, such as is shown in FIG. 2. Following the completion of the operation as performed by mechanism 13, the wire as shown in FIG. 2 is fed across the pulley l4 and into a stamping machine comprising two sets of dies, the machine being generally designated by the numeral 15. The two sets of dies constituting the machine 15 convert the wire from the condition depicted in FIG. 2 to that depicted in FIGS. 3 and 4. The machine generally designated by the numeral 15 is largely conventional in nature, and the invention is primarily concerned with the wire forming mechanism generally designated by the numeral 13 and apparatus directly associated therewith.

Generally speaking, a wire looping mechanism constituting a rotatable device having laterally projecting arms thereon engages the wire as fed in by the track 12 and loops the wire about a pair of pins disposed respectively on the peripheries of a pair of rotatable wheels. More specifically and as best shown in FIGS. 1, 5 and 6, a pair of

wheels

16 and 17 are rotatably mounted about shafts l8 and 19. As may be best understood from FIG. 6, the axes of

shafts

18 and 19 are angularly disposed with respect to each other, it being apparent particularly from FIG. 6 that the axes indicated by the

center lines

18 and 19 in FIG. 6 are disposed in a vertical plane with their point of intersection constituting a vertex.

A plurality of radial pins 20 are disposed about the periphery of wheel 16 and a similar plurality of pins 21 are disposed about the periphery of the wheel 17. The pins such as 20 are individually staggered relative to the pins such as 21 to facilitate looping the wire into the configuration shown in FIG. 2.

From the above description and particularly from FIG. 6, it is apparent that the pins 20 are spaced a maximum lateral distance from the pins 21 when particular pins occupy their uppermost positions such for example as that immediately below the wire holding means designated by the numeral 22. When the pins occupy the diametrically opposite or lowermost position they are disposed at a minimum lateral spacing from each other while points in between constitute points of intermediate spacing.

The wire W is fed in via track 12 and is looped about the pins 20 by virtue of the rotatable element 23 on which arm 24 is pivotally mounted at pivot point 25. A cam follower 26 rides in an appropriate fixed cam surface and imparts predetermined desired swinging movement of arm 24 about center 25. Thus as is best shown in FIG. 6 clockwise rotation of arm 24 causes the lateral projection 27 thereon to engage the wire at W1 and to loop the wire W1 downwardly and about the particular one of the pins 20 which is disposed below the wire W1. Continued rotation of arm 24 causes the course W1 of wire W to ride above the adjacent pin 21 on wheel 17. Thereafter releasing means in the form of arm 28 oscillates about its shaft 29 to cause the inturned end 30 thereof to engage the end of course W1 thereby to force the loop W2 of the wire W into snug engagement with the periphery of wheel 17. Continued rotation of rotatable element 23 causes the arm 31 pivotally mounted at 32 to engage a subsequent course of the wire such as is designated in FIG. 2 at W3 to form a loop about pin adjacent thereto. Thus

arms

24 and 31 alternately form loops about the

pins

20 and 21.

As the particular undulation of the wire W which is adjacent the releasing element moves upwardly and in a clockwise direction due to the clockwise rotation of

wheels

16 and 17 as viewed in FIG. 6, the particular strand is tightened about the

pins

20 and 21 because the pins continue to move apart until an uppermost position is reached immediately below the holding pinion 22. The tension of the strands of wire at the uppermost position conceivably could force the wire to pop away from the pin. This possibility is precluded according to a feature of the invention by means of the hold down pinion 22 which is rotatably mounted on shaft 31A in such manner that the teeth thereof engage pins 20 as well as the strands of wire and thus securely hold the wire in snug engagement with the pins 20. The portion of the wire adjacent pin 21 is held down by means of a holding down block 32 fixed in position adjacent the holding pinion 22 as is obvious from FIG. 6. Thus aecording to a principal feature of the invention, the wire is looped about the pins such as 20 and 21 and then, due to the movement away from each other as described, a set bend is formed in the wire as is represented by FIG. 2 without appreciably changing the disposition of the undulations along the length of the strand.

As explained, the releasing means 28-30 forces the wire W2 against wheel 17 and of course effectively releases the projection 27 to allow subsequent rotation thereof. The other side of the strand in the region adjacent the pins 20 is held in secure engagement with the wheel 16 by means ofa reciprocable plunger 33 which is driven in proper synchronism with the rotation of the

wheels

16 and 17 so as to perform a wire holding operation at the proper time sufficient to hold the wire in place and to move it clear of entanglement with operation of the

projections

27 and 27A. After the

wheels

16 and 17 rotate through a certain angle of movement the strands of wire are held down by the arcuate fixed arm 34 and roller 35 aids in squaring up the parts of the wire such as W2 by rolling in close contact with the flat sides of the pins 21.

In order to prevent entanglement of the wire W1 with certain portions of the mechanism, a fixed finger 36 is mounted alongside course W1.

Rotary motion is imparted to the

wheels

16 and 17 by means of gear 37 which is rigidly affixed to wheel 16 and which is rotated by means of driving pinion 38. Pinion 38 is disposed on shaft 39 as best shown in FIGS. 1 and 9 which in turn is driven by the gear box 40 and drive shaft 41. Rotary motion is imparted to drive shaft 41 by a driving belt or chain 42 which in turn is coupled to driving motor M. Hand wheel 43 is directly connected with shaft 41 and may be utilized to operate the machine manually if desired. Shaft 41 is rotatably supported on the frame structure by means of bearings such as are indicated at 44, 45 and 46.

Forthe purpose of imparting rotary motion to rotatable looping element 23, a driving belt 47 cooperates with a pulley 48 mounted on shaft 41 and imparts rotary motion to a pulley 49 secured to a sleeve type hollow shaft 51 mounted within bearing 50. Rotatable element 23 of course is securely affixed to shaft 51. By this means rotary motion is imparted to the rotatable looping device 23.

As explained the plunger 33 is arranged to reciprocate and impart wire holding movement to the wire adjacent pin 20. This plunger 33 is disposed within the shaft sleeve 51 and is biased toward the left by compression spring 52. Reciprocal motion is imparted to plunger 33 as is best shown in FIG. 8 by means of an arm 54 pivoted at 55 and operated in an oscillatory fashion by means of link 56 connected by bolt 57 to operating rod 58. Operating rod 58 is connected at 59 by an eccentric which is disposed about and operated by the shaft 41. Arm 31 is omitted from FIG. 8 for the sake of clarity.

For the purpose of operating the releasing arm 28 and as is best shown in FIG. 8, a pivot 60 is provided for arm 28 which is oscillated by operating arm 61 which is connected by bolt 62 to operating rod 73 which at its near end is connected by an eccentric 64 with main drive shaft 41. Thus rotation of shaft 41 imparts oscillatory movement to releasing arm 28 to release the wire W2 and to force it to slide down around the pin 21 and to release the transverse part 27 of looping arm 24.

The motion of arms such as 24 and 31 about their centers of

oscillation

25 and 32 respectively is controlled by cam surfaces forming integral parts of structure fixedly mounted within the rotatable element 23. These surfaces are of conventional configuration and the detailed showing thereof is not deemed necessary. Suffice it to say that the arm 24 following looping of the wire about pin 21 must swing upwardly in order to commence a subsequent wire looping operation whereby the portion W1 of the wire W is loop'ed around pin 20 on wheel 16.

For the purpose of causing the wire formed as indicated in FIG. 2 to be released from the peripheries of the

wheels

16 and 17, a wire removal structure best shown in FIG. 1 is indicated in dotted lines at 75 and causes the wire to depart from contact with the

wheels

16 and 17 and to loop upwardly as indicated at W4. The completed structure as indicated in FIGS. 3 and 4 is depicted generally at W5 following bending from the condition shown in FIG. 2 to that shown in FIGS. 3 and 4 by the mechanism 15 which as pointed out above is more or less conventional.

In order to insure that the

wheels

16 and 17 operate at the same speed, and as best shown in FIG. 9, these wheels are interconnected by structure generally designated in FIG. 9 by the numeral 65. Preferably structure 65 constitutes a plurality of face contacting metal plates affixed at their center to shaft 18 on which sleeve 66 is mounted and which in turn supports wheel 16. Mounting bolts 67 are affixed at 68 to structure 65 and are slidable within the apertures 69 formed in wheel 16. Thus the

wheels

16 and 17 rotate in unison, wheel 17 being driven by wheel 16 which in turn is driven by pinion 38.

In order to impart an angular disposition to the

shafts

18 and 19, a pair of sleeves such as 66 and 70 are provided with skewed bores 71 and 72 which are not aligned with the cylindrical supporting rod 18A and by virtue of these

non-aligned bores

66 and 70 resting on the circular rod 18A, the

wheels

16 and 17 are farther apart at their topmost portions such as are indicated by the distance 73 which distance is a maximum spacing for the wheels and the adjacent pinions. Likewise spacing 74 at the bottom of the wheels is a minimum.

From the above description it is apparent that the removal of the formed wire occurs near the minimum spacing designated by the numeral 74 by virtue of the removal device 75 whereas the looping operation occurs where the spacing is intermediate maximum and minimum as is represented by the part of the wire immediately adjacent to the wire holding means in the form of oscillatable releasing means 28-30. Of course the wire is tightened as the wheel rotates clockwise as viewed in FIG. 6 from a position adjacent arms 24 and ing the spacing between said pins after the strand of wire is looped about said pins so as to impart a tension force to said strand of wire while urging the strand of wire against a side of at least one of said pins to cause the wire to conform generally with the shape of said side of said one pin and to cause the undulations of said wire to become stretch-set without appreciably changing the initial disposition of the strand of wire relative to said pins and without shifting the undulations along the length of said strand, and subsequently decreasing the spacing between said pins to facilitate removal of the undulations therefrom.

2. A method according to claim 1 wherein spaced ad- 28 to a maximum tension immediately below the holdjacem Pins occupy a Spaced relationship to each other ing means 22.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

which is intermediate their minimum and maximum spacing when the looping of a strand of wire is completed thereabout.

3. A method according to claim 1 wherein spaced ad- I. A method for imparting an undulatory configurajacent pins occupy a spaced relationship to each other tion to a strand of wire comprising the steps of looping the strand of wire about spaced adjacent pins to provide undulations having straight parallel sides, increaswhich is approximately their minimum spacing when the strand of wire is removed therefrom.

Claims

1. A method for imparting an undulatory configuration to a strand of wire comprising the steps of looping the strand of wire about spaced adjacent pins to provide undulations having straight parallel sides, increasing the spacing between said pins after the strand of wire is looped about said pins so as to impart a tension force to said strand of wire while urging the strand of wire against a side of at least one of said pins to cause the wire to conform generally with the shape of said side of said one pin and to cause the undulations of said wire to become stretchset without appreciably changing the initial disposition of the strand of wire relative to said pins and without shifting the undulations along the length of said strand, and subsequently decreasing the spacing between said pins to facilitate removal of the undulations therefrom.

2. A method according to claim 1 wherein spaced adjacent pins occupy a spaced relationship to each other which is intermediate their minimum and maximum spacing when the looping of a strand of wire is completed thereabout.

3. A method according to claim 1 wherein spaced adjacent pins occupy a spaced relationship to each other which is approximately their minimum spacing when the strand of wire is removed therefrom.