US3590883A

US3590883A - Method and apparatus for manufacture of wire clips

Info

Publication number: US3590883A
Application number: US816716A
Authority: US
Inventors: Josef K Kihs
Original assignee: Rohn Manufacturing Co
Current assignee: Rohn Manufacturing Co
Priority date: 1969-04-16
Filing date: 1969-04-16
Publication date: 1971-07-06
Anticipated expiration: 1988-07-06

Abstract

Apparatus and method for automatically producing bent wire clips comprises a vertical and horizontal wire straightener which receives and straightens a continuous length of wire, a hitch feed assembly through which the wire passes and which is adjustable to measure and intermittently feed the exact length of wire required for the various sized clips, a wire cutoff assembly, a wire-forming means and a grommet inserting means. As the wire piece is cut off from a length of continuous wire it is gripped by a pair of upper and lower coacting pressure plates which clamp a central portion of the wire piece and secure it during formation of the clip ends. To form a spiral end standoff clip that may be snapped on a cylindrical pole the wire forming means comprises a rotating and laterally movable spiral twist winder which forms the one end of the wire piece about a twist wind arbor while a grommet hook has been formed on the forward end of the wire piece. An insulating grommet may be supplied by a feed system and pushed into the grommet hook by a synchronized air ram. The upper and lower pressure plates now release the finished product and the same is blown off the spiral twist winder onto an extension arm from which it may be counted and packaged.

Description

United States Patent [72] inventor Jose! K. Kills Primary Examiner-Lowell A. Larson Hamilton, Ontario, Canada Attomey- Hill. Sherman, Meroni, Gross & Simpson [21] Appl. No. 816,716 [22] Filed Apr. 16, 1969 5 patemed 1 971 ABSTRACT: Apparatus and method for automatically 7 Assign Rohn Ma fmri Cm producing bent wire clips comprises a vertical and horizontal Peoria, wire straightener which receives and straightens a continuous length of wire, a hitch feed assembly through which the wire passes and which is adjustable to measure and intermittently feed the exact length of wire required for the various sized clips, a wire cutoff assembly, a wire-forming means and a [54] METHOD AND APPARATUS FOR MANUFACTURE grommet inserting means. As the wire piece is cut ofi from a or WIRE Cups length of continuous wire it is gripped by a pair of upper and 22 claims 32 Drawing Figs. lower coacting pressure plates which clamp a central portion of the wire piece and secure it during formation of the clip 11.8. C. ends To form a piral end tandoff that may be snapped /82 on a cylindrical pole the wire forming means comprises a lntrotating and laterally movable spiral winder forms 40/1, 7 the one end of the wire piece about a twist wind arbor while a grommet hook has been formed on the forward end of the wire piece. Anjnsulating grommet may be supplied by a feed [56] Rem-cum Cm system and pushed into the grommet hook by a synchronized UNrrED STATES PATENTS air ram. The upper and lower pressure plates now release the 1,562,998 11/1925 Van Orman 140/82 finished product and the same is blown off the spiral twist 2,230,818 2/1941 Stewart 140/92 winder onto an extension arm from which it may be counted 2,517,436 8/1950 Jones 140/102 and packaged.

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sum 11 or 12 METHOD AND APPARATUS FOR MANUFACTURE OF WIRE CLIPS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention generally relates to wire-forming apparatus and method of wire working and is particularly directed to the apparatus and method for producing a wire standoff clip for electrical wires which clip has one end adapted to be attached to a cylindrical pole and the other end adapted to carry an insulator for receiving the electrical wire. More specifically, the clip end adapted to be attached to the cylindrical pole has a substantially spirally wound wire section formed so as to encircle the pole or pipe.

2. Prior Art Wire standoff clips having substantially spiral ends for engaging a cylindrical pipe or rod are shown for example in my U.S. Pat. No. 3,263,026 and by my copending U.S. Pat. application Ser. No. 774,045, filed Nov. 7, 1968. The apparatus and method of making these clips, however, was quite different prior to my invention herein. Thus, prior to the invention herein standoff clips were made in a generator-type apparatus wherein the wire was passed through a series of rollers that force one end and then the other into forming dies which effect the bending operation. This type of device is totally unrelated to the present invention.

The problems with the prior art device included the fact that it was slow, extremely complex and subject to high maintenance requirements. Because dies had to be cut for each size variation any slight changes were very expensive. Moreover the prior art machines did not insert the grommet in the hook portion, but this required a further and separate operation.

SUMMARY OF THE INVENTION An apparatus according to my invention overcomes the problems associated with the prior art and produces wire clips economically at a higher rate in a convenient, very trouble free manner. I have produced a compact completely synchronized apparatus that will produce clips of various configurations but which is shown as producing a standoff clip having a spiral twist on one end and a grommet hook on the other.

A wire straightener relieves any residual stresses which may have been in the wire previously. This straight wire is automatically measured and fed by means of a hitch feed assembly and associated control linkages, through a cutoff assembly and into the wire forming portion of the machine. Prior to being cut off the wire is gripped on both sides of the cutoff knife by a gripper means in the cutoff assembly and by a pair of vertically disposed pressure plates in the wire forming means. The pressure plates initially defonn the clip adjacent each end while the remainder of the wire forming is accomplished by rotating fonning means. The twist end forming means generally comprises a stationary twist arbor, a twist wind roller adjustably associated with a twist wind head. As the twist wind roller is forming the wire about the twist arbor an internal cam operated twist head control means moves the twist wind roller laterally to form a spiral. At the hook end of the clip several variations in hook configuration are set forth for purposes of illustration. For a conventional round grommet a forming wheel synchronized by cam means with the other operations of the machine bends the wire by a grommet hook arbor that does not rotate. In this embodiment a Syntron" grommet feed means is provided to feed the grommets down a rail guide means so that they are positioned adjacent the hook opening. An air pressure ram synchronized to the operation of the apparatus by a cam means, is activated to move the elastic grommet into the hook. This operation is carried out with the air ram lined up substantially coaxial with the grommet hook arbor. The grommet hook arbor is laterally retractable out of the plane of the hook thereby allowing the grommet to be snapped into place.

On the embodiment where a square or arrowhead-shaped grommet is to be attached to the standoff clip, a square hook end is provided by substituting a different grommet hook arbor and changing the roller to a cam forming means. Also the air pressure supply lines are changed to bring into action a pressure tool ram that is aligned generally coaxial with the straight piece of wire. In the production of this clip after the square hook has been formed the cam actuated air ram forces a pusher tool to bend the hook portion at an angle approximately to the axis of the wire portion held by the pressure plates. It is the practice to insert the square hook grommets in the field and thus my apparatus does not add these grommets.

In the method for forming a wire standoff clip the hitch feed mechanism is adjusted for the length of wire to be fed into the wire shaping means in accordance with the size and configuration of the clip desired. After the desired length of wire has been fed into the machine a pair of pressure plates firmly secure the piece of wire to be cut off on one side of a cutoff assembly while a gripper pin holds the wire on the opposite side of the cutoff knife. After the cutoff has been effected the lower pressure plate is moved upwardly by a cam against the spring biased upper pressure plate. In so moving the pressure plates cause the wire length to be bent against the twist wind arbor and the grommet hook arbor. At this point the grommet hook roller begins from a position of approximately 6 oclock and proceeds counterclockwise about the twist wind arbor to form a round hook. As the hook forming operation is being completed the twist hook roller begins a clockwise movement about the twist wind arbor. Simultaneously with the rotation of the twist wind roller the twist wind head is moved laterally so that the roller transcribes a spiral path about the arbor. During the formation of the twist which may be about 1% turns, the round hook grommet may be inserted by the air ram. As the twist wind roller approaches the end of the piece of wire the pressure plates are relaxed so that when the roller, continuing in its clockwise direction about the arbor, passes the end of the wire the resulting wire spring back will be absorbed throughout the entire clip rather than just in the spiral wound portion of the clip. This wire spring back is caused by the residual stresses in the 10 gauge 62 carbon galvanized wire advantageously used in the clips.

When the clip is to be formed with a square hook the square hook forming means are substituted for the round hook forming means, the second internal cam means is changed and the air bases are switched from the grommet inserting ram to a pusher tool ram. With the exception that the pusher tool bends the completed hook at an angle to the clip instead of a grommet being inserted, the method of forming the square hook is substantially the same as the method of forming the round book. As with the round hook an air blast means synchronized to the operation of the apparatus blows the completed clip out of the wire forming means and down an extension of the twist wind arbor to be collected and packaged.

While the invention may be described in terms of the apparatus and method as a whole it is to be understood that I consider various subcombinations and submethods as being included in my invention also. Other objects, advantages and features will become more apparent with the teachings of the principles of the invention in connection with the disclosure of the preferred embodiments thereof and the specification, claims and drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of the complete apparatus of my invention;

FIG. 1A is an elevational side view taken along the lines IA-IA in FIG. 1;

FIG. 2 is a generally schematic representation of a portion of the wire forming means showing the wire as it is being fed into the wire forming means just prior to being cut to length;

FIG. 3 is an enlarged view of the wire hitch assembly subcombination;

FIG. 4 isan enlarged view of the cutoff assembly subcombination to more clearly illustrate the function thereof;

FIG. 5 is a cross-sectional view taken along the lines V-V in FIG. 2 illustrating how the wire is fed into a groove in the upper pressure plate;

FIG. 6 is an elevational cross-sectional view of the interior of the apparatus taken along the lines VI-VI in FIG. 1A;

FIG. 6A is an enlarged detail of an internal cam means;

FIG. 7 is a cross-sectional plan view of the details of the hook forming portion of the apparatus;

FIG. 8 is a perspective elevational view illustrating a step in the formation of the wire clip and showing clearly the grommet feed and inserting means;

FIG. 9 is a perspective view similar to that shown in FIG. 8 but illustrating a further sequence in the formation of the round hook wire standoff;

FIG. 10 is a perspective view such as shown in FIG. 8 illustrating a further sequential operation in the formation of the round hook grommet clip;

FIG. Ill is a perspective view illustrating a sequential step in the formation of a round hook clip and further shows a completed clip;

FIG. 12 is an elevational end view showing only the twist wind head control means;

FIG. 13 is a cross-sectional view of the twist wind head and a portion of the control means therefore;

FIG. 14 is a cross-sectional view taken along the lines XIVXIV in FIG. I2;

FIG. 15 is an enlarged detail of a portion of the twist wind head control means of FIG. 12;

FIG. 16 is a cross-sectional elevational view taken along the lines XVI-XVI in FIG. 1A;

FIG. 17 is a perspective view illustrating a sequential operation and the formation of the square hook grommet clip;

FIG. 18 is a perspective view illustrating a further sequence in the production of the squarehead standofi clip;

' FIG. 19 is a perspective view illustrating a sequential step in the formation of the square hook grommet clip;

FIG. 20 is a view of an element used in the formation of the square hook grommet;

FIG. 21 is a schematic representation showing the wire drawn from a coil about to be cut;

16. 22 is an enlarged schematic view of a cut length of wire in an initial bending stage;

FIG. 23 is a schematic representation of a sequential bending step;

FIG. 24 is a schematic view illustrating a later sequential stage in the bending of the wire clip;

FIG. 25 is a view of a round hook spiral and standoff clip in a completed bending stage;

FIG. 26 is a perspective view of a completed round hook wire standoff clip having a grommet inserted in the hook;

FIG. 27 is a general plan view of the clip of FIG. 26;

FIG. 28 is a view of one end of a clip illustrating one stage in the bending of a square hook clip;

FIG. 29 is a later stage in the bending of the square hook clip of FIG. 28 showing the hook portion bent at 90 to the central portion of the clip;

FIG. 30 illustrates the portion of the clip of FIG. 29 having a square hook grommet inserted therein.

DESCRIPTION OF THE PREFERRED EMBODIMENT Wire Straightener Assembly Referring to FIG. 1 the apparatus embodying my invention may be clearly seen. As shown, a continuous length of wire 10 drawn from a convenient source such as a large spool not shown approaches a wire straightener assembly 20 which includes a plurality of opposed rollers 21 which rotate about a vertical axis and a plurality of rollers 22 which rotate about a horizontal axis that is disposed perpendicular to the axis of the wire 10. When the wire 10 leaves the wire straightener as' sembly 20 it will be, for purposes of this operation, practically straight and any residual stresses caused by having been coiled or otherwise packaged will have been eliminated from the wire.

Hitch Feed Assembly After leaving the straightener the wire 10 passes into and through a hitch feed assembly generally indicated at 30. It is the function of this assembly 30 to automatically measure a length of wire from the end of the continuous wire and to feed this predetermined length of wire into wire-forming mechanism as is shown in FIG. 2 for example. To accomplish these functions the hitch feed assembly 30 includes a body portion 32 having a gripper means 3p thereon that allows movement of the gripper over the wire on a return stroke away from the wire forming means but which upon the feed stroke or forward movement toward the wire forming means is biased against the wire to firmly grip it for movement of the wire into the wire shaping mechanism. A guide wheel means 34, 35 ride on a guide rail 36.

Details of the wire hitch feed assembly are shown in FIG. 3. The body portion 32 has laterally projecting portion 32a having a wire-receiving slot 23b therein. A large slot means 320 receives the gripper member 31 therein which gripper member is pivoted about a pivot means 31a so that it is rotatable in the vertical plane which passes through the axis of the wire. A biasing means 32d urges the gripper member clockwise. The vertical gripper member generally functions in an overcenter manner and thus is of a length whereby when the wire is in the channel 32b the gripper member 31 will abut thereagainst and so that on the forward movement of the feed stroke it will bite into the wire to securely grip it for forward movement. The hitch feed assembly is reciprocal between a first position away from the wire-forming means and a second position closer to the wire-forming means.

Movement of the hitch feed assembly and measurement of the wire length to be fed is accomplished by a control means best seen in FIG. I which includes an arm member 38 pivoted at an upper end about a pivot means 39 on the machine side frame A. An adjustable clamp 40 may be slid along the length of the arm 38 and secured at various points therealong. A first link member 42 is pivotally attached at one end to the adjustable clamp member 40 by pivot means 43. At its outer end it is pivotally attached to a second link member 44 by a pivot means 45. The second link member 44 in turn has at least one and may, as shown, have two or more pivot receiving holes or means 46, 47. Member 44 is shown pivoted about a first pivot point hole 46 through which there projects a pivot pin 46a that is secured to a machine frame side plate A. The upper end of the second link member 44 may be pivotally attached at 43 to a third link member 49 which is connected with the hitch feed body 32 by a pivot means 50. The second pivot point hole 47 may be provided in the second link arm 44 to allow a greater range of wire lengths that may be accommodated by the hitch feed assembly.

A gauge or measuring means 51 attached to the arm 38 facilitates consistent setting of the clamp 40 on the arm 38 to thereby insure uniform wire lengths being fed into the wireforming mechanism.

A follower support 53 is secured to the arm 38 at one end and supports at a remote end a follower roll 54 which roller rides on a cam 55. The cam 55 will rotate clockwise forcing the arm 38 also in a clockwise manner against the force of the biasing means 57 until the follower support 53 bears against an arm return means 56 whose function it is to provide the extra force necessary to unhitch the gripper means 31 between the feed and return strokes of the hitch feed 30. The arm return means 56 comprises a housing 56a receiving a plunger 56b therein and a tension adjustment 560 for a biasing spring not shown but which may be received in said housing. This return means may not be necessary in ordinary usage, however, it is provided as an insurance that there will never be a pause in the motion of the arm 38. It is recognized also that a change in the configuration of the cam may be provided which would cooperate with the spring biasing means 57 operating on the arm 38 to provide the same effect.

It should be noted here that the first external cam 55 is fixed to a driving axle 60 to which is also fixed second and third external cam means 61 and 62 respectively, as well as first and second internal cams 120 and 163 respectively. In this manner the feed is coordinated with the other operations of the apparatus to provide a smooth and efficient operation. A single drive means operates the cam. drive shaft 60 and thereby synchronize the operation of the entire apparatus.

An infinite number of wire lengths may be provided by sliding the block 40 along the arm 38. The gauge 51 facilitates consistent setting. This may be termed the fine adjustment and provides a first range of wire lengths. By changing the pivoting of the second link member 44 about the first pivot point 46a from 46 to 47 a second range of links is provided when the second link 44 is connected by means of hole 47 to the pivot point 46a. Likewise further holes may be provided in the link member to add additional ranges of wire lengths. This range may be very broad.

Thus, for example my standoff clip article is currently being made in 36 different sizes which take wire lengths of l l to 22 inches. These ranges are not to be construed as limiting and lesser or greater ranges may be produced depending upon the size of the machine. The provision on the arm 38 of size indicating means 51 allows the operator to easily change the apparatus to accommodate the formation of clips of various sizes. Other adjustments on the machine further allow variations in size and configuration of the articles produced. Thus, a gauge means 73 on the machine side frame A cooperates with an indicator 74 on the cutoff assembly 75 to readily determine wire lengths.

Cutoff Assembly After the wire has been fed into the wire-forming apparatus a predetermined length the next operation is the cutoff sequence. Again referring to FIG. 1 there may be seen a vertical cam follower arm 70 having a follower roller 71 at its lower end riding on the third cam means 62. The arm 70 is held in place by adjustable slip joints 72 that allow vertical movement but secure the arm 70 against lateral movement and by a stabilizer extension 70a that has one end attached to the arm 70 and is pivoted about the other end at a pivot 85a secured to frame A.

A cutter assembly generally indicated at 75 is operated by the arm 70 to sever the wire into predetermined lengths. This assembly includes an upper jaw 79 having a wire receiving passageway 80 therethrough. The upper jaw has a first end which accommodates a pivot means 78 and a second end having an opening 80b of said passageway 80 therein. A lower jaw 77 is pivotally attached to the upper jaw 79 at the pivot 78. The lower jaw has a knife blade portion 76 upstanding therefrom and movable across the opening 80b to sever the wire. The lower jaw 77 has a locking pin 81 centrally positioned therein between the pivot and the cutofi means. The locking pin 81 has a head extending through an intersecting passageway 80a in the upper jaw portion and is movable into and out of the passageway 80. The locking pin has a lower base portion 810 below the lower jaw which engages a biasing means 81b therebelow that biases the locking pin upwardly so that as the lower jaw swings upwardly into cutting relation with the wire it allows the locking pin to move upwardly against the wire in the passageway 80 to hold it during the cutting of said wire.

Referring to FIG. 1 and particularly the cam members 55, 61 and 62 it should be noted that all are fixed in relation to each other and rotate on the shaft 60. It may be seen that in the position shown the arm 70 through its roller 71 is riding on the third cam 62 and as the cam moves in a clockwise direction it moves at 62b the cutting knife 76 away from the wire. As the cam 62 rotates clockwise however, it may be seen that as the roller 71 reaches the area designated 62a that the follower arm 70 will move upwardly bringing into play the cutter knife 76. At the same time, the locking pin 81 as shown in FIG. 4 is allowed by the upward movement of the lower jaw to move into spring biased clamping engagement with the wire 10 to hold that end while the hitch feed moves back to its initial feed position.

As may be seen in FIG. 5 the wire slides into the groove 93a in the upper pressure plate 91. Prior to the cutting of the length of wire that will be formed into a clip the lower pressure plate 90 will be forced upwardly by the vertical arm 88 and the horizontal follower arm 35 with its follower roller 86 riding on the second cam member 61 and moving in response thereto. The initial clamping of the wire by the lower jaw 90 against the upper jaw 91 will not move the upper jaw 91 but will merely hold the wire secufe against movement during the cutting operation. In actuality this has been a slight pause in the upward movement of the lower pressure plate. In fact the pause is caused by the time necessary for the lower pressure plate 90 to overcome the very high SOD-pound spring bias of the upper pressure plate. It is thus clear that as the wire 10 is cut it is being gripped on the feed side by the locking pin 31 as shown in FIG. 4 and is clamped on the wire-forming side by the lower pressure plate 90.

Wire-forming Means A follower arm 85, pivotally connected at one end to a pivot 85a on the machine frame plate A and having a follower roller 86 at its other end riding on the cam 61, has pivotally connected thereto at a generally central portion thereof a vertical arm member 38. The vertical arm member 88 is held in its vertical position by a parallel arm member 89 which runs parallel to the arm 85 and in effect forms a parallelogram so that the member 88 may move upwardly into engagement with a lower pressure plate 90.

Referring now to FIG. 2 a lower pressure plate 90 and an upper pressure plate 91 are shown in the position just as the wire 10 has been fed to its full length and is ready to be cut by the knife blade 76 and just before the lower pressure plate 90 is moved into an upper initially clamping and subsequently forming position. At this point the wire 10 may be seen in FIG. 5 to be aligned within the groove 93a on the lower edge of the pressure plate 91 and between what may be referred to as the teeth 93.

The lower pressure plate 90 has adjustment means 92 which may take the form of a slot with an offcenter screw. Likewise the upper jaw 91 has similar adjustment means 95. These adjustment means 92 and 95 allow vertical adjustment of the pressure plates to align them with the feed wire, the various size twist arbors 100, and the grommet end arbors 101. It is to be understood that the size of these arbors will change depending upon the desired configuration of the standoff clip.

A twist wind roller 104 is rotatably connected by a pin 106 to a first end of a holding arm 108 that is in the form of a horn and which in turn is pivotally attached at a central portion 110 to a twist spiral winding head 112. The roller 104 has a V- shaped groove on its peripheral edge which will surround the wire 10 and which will form with the twist arbor a restricted area that will hold the wire 10. As may be clearly seen in FIG. 13 this area will have just enough room to allow the wire to pass through freely between the roller and the arbor. Likewise the upper pressure plate in its initial position as shown in FIG. 5 would just allow the wire 10 to freely pass through the groove 93a.

Depending upon the size of the twist arbor and the diameter of the wire, an adjustment means 114 gearing against the pointed tip 1080 on the second end of the horn-shaped holding arm 108 will allow adjustment of the area and space between the twist arbor 100 and the roller 104.

As the cams 62, 61 and 55 turn in fixed relation clockwise with the driving shaft 60 the roller 86 rides on the cam 61 and from the position shown in FIG. 1 moves the follower arm 85 and the attached vertical member 88 upwardly against the lower pressure plate 90 moving said plate into a firm clamping engagement with the upper plate 91 as the wire is cut by the blade 76. A spring means 87 extending from the follower arm 85 to a bar 87a connected with the apparatus support C urges the follower roller 86 against the cam 61.

After the wire 10 has been cut as would be indicated by the point 62a on the cam 62 it can be seen that the cam 61 will continue to force, through the various arms and vertical members, the lower pressure plate 90 upwardly to a level indicated by a line 105 extending through the midpoint of the twist wind arbor 100 and the grommet hook arbor 101 and thereby initially form a bend in the wire on one side about the twist arbor 100 and on the other side about the grommet end arbor 101. The upper pressure plate 91 is spring biased downwardly by a spring means 115 so that the lower pressure plate 90 must move upwardly against this spring pressure which I have found may advantageously be about 500 pounds.

This high pressure may be supplied by a spring means 115 comprising a pair of coiled springs 116 restricted between an upper cap 116a and a lower stabilizer means 117. The stabilizer means 117 effectively is of a V-shape configuration having the two V-legs pivoted to side plate B of the frame at two separated points 1l7b to provide stability and even pressure distribution to the upper pressure plate 91.

The twist arbor 100 may vary in size from 1 inch to perhaps 2% inches or more. The external cams may also be changed, however, we have found that a universal cam may be provided whereby the various size arbors may be accommodated.

As will be hereinafter described in greater detail with respect to FIGS. 8 through 11 and 17 through 19, the roller 111 or cam 111.: is attached to a rotatable sprocket 109 and rotates about the hook arbor 101 or 101s respectively to form the round and square hooks respectively. On the other side of the

pressure plates

90, 91 the roller 104 driven by the rotating head 112 moves in a clockwise spiral path to wrap the wire 10 about the stationary arbor 100. Before the roller 104 has completed winding the wire 10 about the twist arbor 100 the lower and

upper pressure plates

90, 91 must partly release. This step in the method of manufacture forms an important part of my invention since if the pressure plates are not relaxed the twisted portions of the wire would spring back an excessive and inconsistent amount. By relaxing the pressure plates this spring back is absorbed by the entire clip and although there still is a spring back it is relatively small and very uniform. It must be understood that the wire used to make the standoff clips is very hard and has a high carbon content such as for example, point 62 carbon that gives the spring clip the resilience necessary to securely attach it to a pole means. An example of the spring back is that a 1% inch arbor will, with the wire spring back, produce a twist of about 2% inches. The empirical determination of the hook and twist end sizes has been found to be accurate and convenient and therefore is used. An example of this spring back may be seen in FIG. 11 wherein it will be noted that the jaws are slightly separated.

The separation of the

pressure plates

90 and 91 to allow the spring back of the spiral portion of the clip to be absorbed by the entire clip is accomplished by keeping the lower plate in place and moving the upper pressure plate 91 further up or away from the lower pressure plate. This additional movement of the upper pressure plate 91 is accomplished by the means shownin FIG. 6 wherein a first internal cam 120 is driven by the shaft 60 by a series of

gears

122, 123 and 124 which in turn are driven by a main drive gear 125 connected by means ofa belt 126 to a pulley 127.

The pulley drive 125, 126, 127 would not be seen in FIG. 6 as is evident by referring to FIG. 1A, however, it has been overlaid thereon in dotted lines for purposes of understanding. The pulley 127 is connected by means of a common shaft 127a with a variable speed pulley 128 as shown in FIGS. 1 and 1A which in turn is connected by a belt means 129 to a motor means 130.

Referring to FIG. 1 it may be seen that the motor 130 is mounted on a mounting block 131 which slides on'a base 132 that may be secured to a bottom rail 133 of the frame means C. Because the variable speed pulley 128 allows a change in its effective diameter depending upon the pressure applied by the belt 129 the effective speed of the apparatus may be changed by moving the motor and its mount toward and away from the variable-speed pulley 120 by rotation of the screw adjustment means 134. A universal joint 135 is provided at the outer end of the adjustment means 134 so that rotation of the adjustment means may be accomplished through an extension 136 having a convenient handle 137 at a point readily accessible to the operator.

In FIG. 6 there is shown a sprocket 125 rotating about an axis 124 which has a gear 124a thereon which gear meshes with a gear 1230 that in turn drives the gear 122 to which the internal cam 120 is attached. A fly wheel 98 as may be seen in FIG. 1A to be mounted on the shaft 124 provides the inertia to insure smooth operation of the apparatus. Turning again to FIG. 6, a follower wheel 140 shown mounted on the follower arm 141 rides on the first internal cam 120 so that as the cam turns counterclockwise the roller 140 will move the arm slightly upwardly as it approaches the point 120a during its rotation. At this point the member 117a through which the upper pressure plate 91 is attached will be moved upwardly by a member pivotally connected at its upper end 145a to the member 1 17a and pivotally connected at its lower end 1451; to the arm 141. A C-shaped portion 1450 allows the provision of adjustment means 146 in the member 145 so that the length of the member 145 may be varied readily in accordance with changes in the clip size and/or operation of the apparatus.

The first internal cam follower arm 141 is connected at a first end 141a by a pivot means 142 to a link arm 143 that in turn is pivotally connected by a means 144 to a sprocket wheel 146. The sprocket 146 is mounted on a hollow shaft 161 that rides on a shaft 161a. Teeth 146a on the sprocket engage an endless chain link belt 147 which moves about a sprocket 140 that rotates on the shaft 100b. An idler sprocket 149 attached to spring-biased arm 150 may be provided to accommodate any slack in the chain. Thus as the cam 120 rotates the arm 141 will follow cam 120 and pivot about the fixed pivot 141c in a reciprocating motion that, by means of link 143, will rotate sprocket 146. This oscillating movement will be transmitted in increased magnitude because of the difference in diameters between the

sprocket

146 and 140 by the chain 147 to the sprocket 148. The sprocket 148 is fixed to shaft assembly 220 that may be seen in FIGS. 12 and 13 to provide the rotary motion for the twist wind roller 104.

A follower arm is pivotally connected on a first end 160a to the shaft 161a. The shaft 161a may be fixed in position between the frame sideplates A and B and supports a shaft 161 that rotates thereon.

At a central position thereon the arm 160 carries a follower roller 162 that will ride on a second internal cam 163. Actually the second internal cam 163 may be as shown in FIG. 6A either the cam 163r or the cam 1633 for the round and square grommet hook constructions respectively. These alternately useable cams may be changed by merely removing an attachment means 163a that conveniently comprises a pair of bolts. After the bolts are removed the cams are quickly reversed and replaced to effect the change from round to square or vice versa. At the second end 160i) of the arm 160 in FIG. 6 an adjustable attachment means 165 secures the first end 166a of a chain 166 that runs over a sprocket 167 which is affixed to and turns a shaft 163. The chain is connected at its second end 166b to a spring means 169 which in turn is secured to the apparatus frame C by means 170. The shaft 168 extends through the apparatus to a drive sprocket 107 seen in FIGS. 2 and 7 which in turn drives the grommet-forming sprocket 109.

During the grommet-forming step the sprocket 167 and the shaft 168 will be turned counterclockwise as is seen in FIG. 6 and the shaft 168 and the drive sprocket 107 will be turning clockwise as seen in FIG. 2 thereby rotating the forming sprocket 109 in a counterclockwise direction. It is pointed out that the grommet end arbor 101 is not attached to the sprocket 109 but projects through a projection 113 so that it does not move with the sprocket 109.

Referring to FIG. 7 the connection between shaft 168 and the drive sprocket 107 may be clearly seen. It may be further seen that the sprocket 109 rotates about a projection 113 and is held in place by an end cap means 184. The arbor 101 slidably extends through the projection 113 and is held in an outwardly biased position by a free end portion 180 of a coil spring 182 vertically disposed in a recess 183 of a machine portion 185. FIG. 19 clearly shows the relative position of the spring 182 and the captivity of its upper end by the frame member 198 and the retaining means 182a.

A slot 101a in the inner end portion of the arbor pin 101 receives the spring end portion 180 to hold the arbor pin against rotation.

The apparatus portion 185 is fixedly attached to the frame sideplate A and has an elongated portion 186 which is shaped so that the end of the wire being rotated about the twist arbor may pass behind it.

The arbor 101 need move rearwardly only in the production of the round hook arbor when the grommet is being inserted. In the production of square hook clips the round hook arbor 101 is replaced by a square hook arbor 101s shown in FIGS. 17 and 18. In this case the square hook arbor 101s is held in position by a setscrew not shown and does not move rearwardly since the square hook grommets are attached in the field because of their construction.

Round Hook Clip Forming Operation It is within the contemplation of this invention that the apparatus may produce clips having at least two different types of end configurations for the reception of a round grommet or a square grommet sometimes referred to as arrowhead grommet. Since there are differencesin the production of the different clips their operations are separately described. FIGS. 8 through 11 illustrate various stages of the round hook clip production while FIGS. 17 through 19 show stages in the square hook clip development.

Referring now to the method of forming the round hook it will be recalled that in FIG. 2 the wire had entered the wire forming means through the cutoff assembly guide 75a and had been fed through the groove 1040 between the twist wind roller 104 and the twist wind arbor 100, through the groove 93a in the upper pressure plate 91 and between the round hook arbor 101 and the round hook-forming roller 111. From this position the lower pressure plate 90 moves upwardly in response to the rotation of the cam 61 and the movement of the follower arm 85 transmitted through the vertical member 88 to a position generally level with the line 105 as shown in FIG. 2. While being held in this position the grommet forming sprocket 109 has rotated counterclockwise bringing the grommet end roller 111 from a initial position of approximately 6 oclock to a position of approximately 2 o'clock as is shown in FIG. 8.

In the stage of production as is shown in FIG. 9 it may be seen that the round end hook is being completed just as the spiral end is beginning to be formed. Thus, the twist wind roller 104 has moved from an initial position of approximately 6 o'clock to a position of approximately 8 o'clock as shown. The free end of the wire sweeps around the twist arbor 100 and behind the

pressure plates

90, 91 and behind the portion 186 of the apparatus shown in FIG. 7.

Referring now to FIG. 10 it may be seen how the head 112 is moving toward the machine frame sideplate A to form the twist end of the clip. FIGS. 12 and 13 also illustrate this lateral movement. It is because of the movement by the head 112 and forming roller 104 toward the machine side frame A that the groove 104a is necessary to guide the wire rearwardly over the stationary arbor 100. At this point in the process the round end has been completely formed and has sprung back slightly as the forming roller 111 has begun to return to its starting position. The pressure plates and 91 may have begun to separate very slightly since the roller 104 is nearing the end'of the twist portion of the clip and the spring back of the clip is eminent. The movement of the upper pressure plate 91 away from the lower pressure plate 90 to allow the spring back to be absorbed by the entire clip has previously been described with regard to FIGS. 2 and 6 which description is hereby incorporated by reference. With the spring back completed and the pressure plates separated, but still holding the clip between their teeth the grommet may be inserted in the round hook by depressing the hook arbor. While I have found it convenient to incorporate the grommet inserting step at this point it may be deferred until the clip has left the apparatus.

The grommet feed mechanism and inserting means therefore may be seen in FIGS. 1, 1A and 8. Thus, in FIGS. 1 and 1A the supply bin 191 with its feed control 192 and upper feed path 193 may be seen positioned a top of the apparatus. From this supply means the individual grommets 206 are fed between a pair of

guide rails

208 and 210 for gravity feed to the point of insertion. The guide rails 208 and 210 are hinged at a point 211 in FIG. 8 and have a spring 212 keeping the pivoted lower portion of the

guide rails

208 and 210 biased outwardly away from the machine and against a collar 205 that is positioned on the outer end of a ram 204 that is operated by a air piston 200. The

air piston assembly

200, 204 is aligned to be generally coaxial with the axis of the grommet arbor 101. An adjustment means 213 on the

rails

208, 210 allows alignment of the final grommet feed level with the grommet end arbor 101 so that when the air cylinder 200 is activated to project the collar 205 toward the arbor 101 it will be aligned with a grommet 206. As may be seen in FIG. 11 the ram and collar move the pivoted portion of the

feed rail

208, 210 against the arbor 101 until it can go no further. With the grommet thus held in position by the collar 205 the ram 204 continues its outward movement through the collar 205 and displaces the arbor 101 rearwardly against the bias of the spring 180 as seen in FIG. 7 until the resilient grommet with its peripheral groove snaps into place in the clip hook portion. A biasing means 2050 may be provided between the collar 205 and a protrusion 204a on the ram 204 to keep the collar 205 biased outwardly against the grommet and feed rails during movement of the arbor 101. As the clip is gripped by the force of the ram the

pressure plates

90 and 91 continue to part as may be seen in FIG. 11 so that after the grommet is in place in the hook and the ram and

collar

204, 205 retract the arbor 101 will be biased outwardly to its original position thereby initially pushing against the grommet and clip to move it from between the pressure plates. This movement or ejection of the completed clip from the wire-forming means is assisted by a blast of air from an outlet 196 in FIG. 8 which may be advantageously positioned below and directed upwardly toward the twist arbor and the

pressure plates

90 and 91. The timing and valving of the air blown outwardly through the outlet 196 will be described in greater detail with respect to the description of FIG. 16.

The air cylinder means 200 has the appropriate

air hose connections

201 and 202 and is supported by

apparatus frame portions

200, 198 and 199.

The elements of this type of feed apparatus are individually known under a trade name Syntron, however, I believe their inclusion in this combination with the wire-forming means and an air ram inserter etc., is unique and produces new and unexpected results. There is also shown in FIG. 8 an adjustment means 75b that allows alignment of the wire feed into the wireforming portion of the machine.

The blast of air from the air outlet 196 will blow the completed clip down a transporting rod 197 which may be an extension on the stationary twist arbor 100 so that the clips may be conveniently counted and further packaged and handled.

It must be understood that the clockwise indications of movement of many of the various elements are to be interpreted with relation to the figure being described and moreover are only exemplary.

It is to be emphasized that the apparatus functions under what may be termed a constant drive and that the movement of the various cams and shafts and driving portions are all coordinated with one another and synchronized so that the apparatus operates quite smoothly and without vibration. In fact, when a fly wheel is attached to the apparatus it functions extremely smoothly and may be rotated by hand to produce samples and to set and align the various elements of the apparatus. In practice I have found that the entire operation may be driven by a 192 horsepower motor using approximately an 85- pound fly wheel. The variable-speed clutch with its convenient control means allows changing the production rate from, for example, 20 to about 75 pieces per minute depending upon the thickness of the wire and the size of the clip to be formed.

From FIGS. 8 through 11 it may be seen that the head 112 has moved toward the machine frame A to form the spiral. In FIG. 11 the head 112 is back against the side frame A of the machine so that the exposed portion of the arbor 100 is at its maximum. In this view the entire twist roller arm 108 and its adjustment means 114 are visible. As the adjustment screw 114a is screwed into the bearing l14b the screw end 1 He will bear on the arm end 108a and pivot the arm 108 about the point 110 fixed to the head 112 to bring the roller 104 closer to the arbor 100.

From FIGS. 8 to 11 it may be seen that the head 112 has moved toward the machine to form the spiral. The apparatus which brings about this lateral movement is further described with respect to FIGS. 12 through 16. Referring to the elevational end view in FIG. 12 it may be seen that the head 112 is attached to a shaft assembly 220 which allows it to move toward and away from the side frame member A. This assembly is shown in greater detail in FIG. 13 where it may be seen that a bearing member 221 bolted to the frame A having a bearing liner 222 receives a cylindrical hollow member 223 in sliding engagement. The bearing member 221 is made with a recess 224 to accommodate the rear head portion 112:: which may bev threaded on to the first end 223a of the shaft 223. At the other or second end 223!) of the shaft 223 the sprocket 148 is affixed thereto to rotate oh the cylindrical shaft 223 in response to movement of the chain 147. An end member 226 has a groove 227 therein to receive an end portion 231 of an adjustable twister lever 230 as may be seen in FIG. 12.

There may be provided an additional bending projection 100a on the twist wind arbor 100 to insure that the free end of the wire forming the spiral twist will be properly bent. Thus in an improved form of my twist clip this bend is provided to give a sure fit with the mast or pole. Also in production of clips on the one inch twist arbor we have found that the pressure required to bend this free end portion is very great, but that with the projection 100a much less pressure is required.

In FIG. 12 the adjustability of the movement of the hollow shaft assembly for the twister head may also be seen. This adjustability may be accomplished by moving the pivot point 242 along the length of the twister lever 230. This adjustability is accomplished by a movement of a slide 234 on a T-bar 235 affixed to the frame side member B. The slide 234 is moved by means of a threaded rod 238 which passes through a bushing 239 affixed to the slide 234. Rotation of the rod 238 by the handle 240 through a guide 241 affixed to the upper portion of the T-bar 235 allows precise and exacting control of the position of the slide 234.

Referring now to the view of FIG. 14 taken along the lines XIV-XIV in FIG. 12 there may be seen the attachment means 235a of the T-bar 235 to the side frame B. An arm 234a has a pivotable twister guide 242 secured thereto by means 243 such that the twister lever 230 will rotate about the attachment means 243.

Reciprocating movement of the twister lever 230 is caused by rotation ofa cylindrical cam 250 shown in FIGS. 12 and 15 which cam is afiixed to the shaft 161. The lower end 232 of the twister lever 230 is pivotally attached to a collar 252 slidable on the shaft 161. On one side thereof the collar has a follower roller 254 biased by a spring means 255 to move on a cam surface 251 of the cylindrical cam 250. The spring may be a tension coil spring secured at its other end to the frame B. Appropriate attachment means 253 fixedly secure the cam 250 to the shaft 161. Thus, as the shaft 161 turns the roller 254 rides on the surface 251 to move the lever 230 about the pivot 242 and thus shift the rotating shaft 220 and its attached rotating head 112 toward and away from the apparatus frame member A whereby the spiral twist is formed at one end of the standoff clip.

Referring to FIG. 16 the adjustable lever may be seen in side view taken along the lines XVI-XVI. In addition frame spacer members 260 may be seen. These spacer members 260 keep the side frame portions A and B in spaced fixed relationship.

There is also shown in FIG. 16 the valve arrangements for the air outlet 196 of FIG. 8 and 19. An air supply line is schematically represented at 270. This air supply line 270 extends past a T intersection with a line 272 and enters a valve 274 which valve is controlled by a follower piston 276 that rides on a third internal cam 277. As the cam reaches a point such as designated by 277a the piston 276 is moved upwardly operating the valve 274 to allow compressed air or equivalent substance to pass through the line 275 to the outlet 196 as shown in FIG. 8 and 19. Regardless of the valve arrangement a shutoff 195 may be provided exterior the machine to override the valve 274. By means of a valve 280 the air passing through the line 272 will be discharged intermittently through a line 282 to the air cylinder 200 where it will serve to actuate the cylinder to insert the grommets at the round head opening. Altemately this air supply is fed to the piston assembly generally designated at 285 which is operative when the square head clip is made to bend the square head at right angles to the central clip portion as will be hereinafter explained in greater detail. The valve 280 is operated by a cam follower member 283 which also will be activated by the third internal cam 277. The cam 277 is driven by the shaft 60 which also drives the first and second internal cams 120 and 163 respectively. In this view the cam rotation will be clockwise. The driving of the cam 121 by means of the pulley 127 is explained with respect to FIG. 6.

Square Hook Clip-forming Operation FIGS. 17 through 19 illustrate sequential stages in the square hook clip formation. To change from production of the round hook to the square hook several basic changes must be made. A first of these changes relates to replacing the cylindrical slidable round hook arbor 101 with a stationary square hook arbor 101s.

A second modification made to accommodate forming the square hook is that in place of the roller 111 as is perhaps best seen in FIG. 9. there is substituted a square hook forming cam 111.: as may be best seen in FIG. 17.

A third change relates to the reversal of the second internal cam means as explained with respect to FIGS. 6 and 6A to synchronize the movement of the forming cam 111s.

A fourth basic structural change involves changing the air supply connections from the air piston means 200 to the piston means 285.

Of course other adjustments such as wire length, speed, etc., may be made to achieve the desired results.

Prior to reaching the position in FIG. 17 the wire had been fed by the hitch feed mechanism between the groove 104a and the twist arbor 100 through the V-shaped groove 93a on the lower edge of the upper pressure plate 91, and between the square hook arbor 101s and the square hook forming arbor 111s. The lower pressure plate had then moved up into position where it held the wire lightly clamped between the

pressure plate

90 and 91. In this light or preliminary clamping position the lower pressure plate 90 paused for a split second while the wire 10 was being severed by the cutoff assembly 75.

It then moved upwardly with the wire firmly clamped until it reaches a point approximately on a line 105 as may be seen in FIG. 2, which line generally extends through the centers of the twist arbor 100 and the forming arbor 101s. The lower pressure plate 90 by means of the cam 61 and arms 35 and 88 has forced the upper pressure plate 91 upwardly against the spring bias of the spring 116 as may be seen in FIG. 1. This upward movement of the

pressure plates

90, 91 served to bend the severed wire 10 between the edge of the lower pressure plate and partially about the twist arbor 100 on the twist end while on the grommet hook end the bend is affected between the edge of the lower 163s plate 90 and the grommet arbor 101s.

Initially the square hook forming cam 111s is in a position of approximately 6 oclock, however, as the

pressure plates

90, 91 move upwardly it begins to rotate counterclockwise in response to the cam 163s and force transmitting means associated therewith bending the wire about the square hook arbor 101:. As may be seen in FIG. 17 it has reached a clockwise position of about 2:30. Again no movement of the twist wind roller has yet occurred.

Referring now to FIG. 18 it may be seen that the

pressure plates

90, 91 have remained in the same position but that the square hook forming cam 111: has moved to a position of approximately 11:30 in FIG. 18 and has further bent the wire 10 about the square hook arbor 101sv The bends in the wire are exaggerated with an overbend so that when the wire springs back it will assume the desired final shape. At this time the twist roller 104 has moved from its initial position of approximately 6 oclock clockwise to a position of about 8:30 in FIG.

' 18. At the same time the twist arbor head 112 is moving away from the plane of the

pressure plates

90, 91 to form the spiral twist as was previously described for the round hook operation.

At this stage in the method of forming the standoff clip it is advantageous to hold the square grommet end in position while the twist roller continues to form the twist end of the clip. This position is held until the roller 104 reaches a position of about 8 oclock.

Sometime after this point the square hook forming cam 111s backs off in a clockwise direction to a position of about 12 oclock and pauses there to allow a J-shaped pusher tool 300 to move in from the right in a horizontal plane, grasp the hook by forward lip portion 301 and bend it outwardly at an angle of about approximately 90". This pusher tool is operated by an air piston means 285 to which the air supply from the grommet inserting air piston 200 has been switched by means of changing the

air supply lines

201 and 202. It thus operates on the same valving discussed with relation to FIG. 16 that was used to operate the air cylinder 200 that pushed the grommets 206 in place. Under normal operating conditions no change in the timing of valving of this operation is necessary.

From FIG. 20 it may be seen that as the pusher means 302 moves in the direction shown by the arrow 304 the kidneyshaped slot 305 will cause the pusher tool 300 and particularly the lip 301 to be moved counterclockwise. From FIG. 19 it may be seen that this movement of the tool 300 will bend the square hook portion outwardly, and around the arbor 101:.

During the time that the pressure tool bends the square end hook at right angles the

pressure jaws

90, 91 are firmly holding the clip and the twist end roller is completing the twist end of the clip. As shown in FIG. 19 the roller 104 has reached a position of approximately :30.

The remainder of the twist-forming operation is similar to that desired with respect to FIGS. 9, l0 and 11 where it is shown that the roller 104 continues around the twist arbor 100 until it is approximately at the end of the wire as is best shown in FIG. at which time the pressure plate 91 moves upwardly slightly to loosen its grip on the wire so that as the roller 104 passes the free end of the spiral end of the wire the resulting spring back may be absorbed throughout the entire clip rather than by just the twist end of the clip.

After the roller 104 has completed forming the spiral it returns in a counterclockwise manner by the drive control means previously set out back to its initial position at 6 o'clock below the twist arbor 100. After the pusher 300 has formed the square hook at right angles to the central portion of the clip it retracts and the square hook forming cam 111s returns in a clockwise motion to its initial point of about 6 oclock on the sprocket 109. At this point the air valve arrangement as described in FIG. 16 allows a blast of air to be emitted from the opening 196 which causes the completed hook to slide down the extension 197 and be packaged or otherwise handled. In practice the twist end of the clip has been bent to assume a completed form of about I541 turns or 450. I have found 10 gauge 62 carbon galvanized spring wire to provide an effective and very durable clip. When these clips slide down the extension 197 their configuration many times is such that they fit together in groups of five and thus may be quickly picked off by a workman five to a hand and packaged. In this manner sorting and counting is eliminated. A further provision to expedite the handling of the clips is to provide a different colored grommet for each size spiral twist end of the clip. With the Syntron"

automatic feed apparatus

191, 192, 193 this change of grommet colors is very readily effected.

FIGS. 21 through 27 illustrate in schematic form the steps and the method of cutting and bending thewire to form the clip. Thus in FIG. 21 it may be seen that a wire 10 is unreeled from a coil 10:: and is cut to a measured length. After cutting the rectilinear wire length is initially bent in what may be termed a central portion 10b although it is to be understood that this portion 10b may occur almost anywhere between the two ends of the cut length. As further shown in FIG. 22 after the initial bend establishes the central portion 10b formation of the twist spiral end 100 has not yet begun while formation of the grommet hook end 10d may have begun.

In FIG. 23 it may be seen that as the grommet hook end 10d is being formed the bending of the twist end 100 is beginning. In FIG. 24 it may be seen that in one embodiment of our method the round hook grommet end has been completed while the spiral twist end 10c is just finishing.

FIG. 25 is a generally plan view illustrating a completed clip with the bend in the free end of the twist 10c to show the extent to which it is bent. FIG. 25 illustrates the step and the method of inserting the grommet 206 in the round hook end 10d. Variations in the precise sequence of the bending operation may allow insertion of the grommet in the end 10d prior to the completion of the twist end 10c. These factors will depend on the size and configuration of the clip. In FIG. 27 there may be seen in generally plan view the completed round hook clip. Inasmuch as the FIGS. 21 through 30 are schematic the spring back which occurs in the formation of the clip is not accounted for. It may be seen that the grommet 206 will turn in the hook 10d to allow insertion of the wire in the slot 206a and then turn to a closed position to hold the wire securely within the insulating grommet.

In FIG. 28 there is illustrated only a portion of the central portion 10b and an end 102 corresponding to the end 10d in FIGS. 22 through 27. In this embodiment the hook 10e is formed in a generally square configuration. After the end 10a has been bent as is shown in FIG. 28 the portion 10b is held firmly in place and the portion We is bent at approximately angle to the portion 10b as may be seen in FIG. 29. In this configuration the end 10a is adapted to receive a grommet 206b. While the grommet 206 may be inserted during the formation of the clip I have found it more convenient to allow the man in the field to insert the grommet 206b.

Although minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted herein all such modifications as reasonably and properly come within the scope of my contribution to the art.

What I claim is:

1. An apparatus for producing wire clips comprising a wireforming assembly which includes a pair of pressure plates adapted to grip a central portion of a cut length of clip wire having a first and second end, and a twist end forming means

Claims

1. An apparatus for producing wire clips comprising a wireforming assembly which includes a pair of pressure plates adapted to grip a central portion of a cut length of clip wire having a first and second end, and a twist end forming means for forming a first end of the wire length in a spiral configuration, said twist end forming means comprising a stationary twist arbor, a twist wind roller rotatably attached to a twist wind roller arm, said arm being pivotally connected to a twist wind head, said twist wind head movable along the length of said twist wind arbor as said roller rotates about said twist arbor to form said spiral configuration on said wire.

2. A method of forming wire clips comprising gripping a central portion of a cut length of wire, forming a hook on a first portion of said wire length on one side of said gripping means and forming a second portion of said wire on the other side of said gripping means into a spiral configuration, and inserting a grommet means in said completed hook portion as said forming steps are completed and ejecting said completed clip having a grommet therein.

3. A method for forming wire clips comprising measuring a length of wire, feeding said length of wire into a wire-forming means, gripping a central portion of said wire in said wire-forming means, cutting said length of wire to leave said measured length of wire in said wire-forming means, bending a first portion of said cut wire length about a forming arbor on one side of said gripping means, bending a second portion of said wire on an opposite side of said central portion about a twist arbor, and moving said wire forming means along said twist arbor laterally while rotating said wire-forming means to thereby form said wire in a spiral configuration.

4. An apparatus for producing wire clips according to claim 1 wherein said twist wind head is connected with a shaft assembly which allows it to reciprocate along the twist wind arbor, said shaft assembly being rotatably connected to a first end portion of a twister lever, said twister lever being rotatably mounted about an adjustable pivot point, a second end of said twister lever being positioned to move laterally in response to a twister lever cam means, said twister lever cam means being geared to move in relation to said shaft assembly.

5. An apparatus for producing wire clips according to claim 4 including a follower arm pivoted about one end and linked to a sprocket at the other end, said follower arm riding on a first internal cam means and movable in response to said cam to rotate said sprocket, a drive means between said sprocket and said shaft assembly rotating said twist wind head in response to the movement of said sprocket, and a drive means for said first cam means.

6. An apparatus for producing wire clips according to claim 1 wherein said wire-forming assembly includes a hook-forming means for forming said second end of the wire length into a hook configuration.

7. An apparatus for producing wire clips according to claim 6 wherein said hook forming means comprises a stationary hook arbor, a sprocket rotatable about said hook arbor, a wire-forming member attached to said sprocket to move about said hook arbor, a drive means for said sprocket, said drive means moving said sprocket in response to the movement of a cam means.

8. An apparatus for producing wire clips according to claim 7 including a grommet-inserting means comprising a grommet supply means positioning a grommet adjacent a formed wire clip hook end, a power ram means aligned with said grommet and said hook arbor, said hook arbor being retractable, said power ram means operable to depress said hook arbor and force said adjacent grommet into said formed hook.

9. An apparatus for producing wire clips according to claim 7 wherein said hook-forming means includes a pusher tool movable in a line parallel to said cut length of wire to bend said completed wire clip hook at an angle to said cut length of wire.

10. An apparatus for producing wire clips according to claim 7 wherein said pressure plates are disposed between said twist end forming means and said hook end forming means, said pressure plates being operable to move said central portion of the cut length of wire between said arbors to bend said cut length of wire against said hook arbor and said spiral arbor, a cam means for each of said hook end forming means and pressure plates, all of said cam means being driven by a common drive shaft.

11. An apparatus for producing wire clips according to claim 1 including a cutoff assembly for cutting the wire in a predetermined length when the pressure plate has gripped the central portion of the wire to be cut.

12. An apparatus for producing wire clips according to claim 11 including a feed means for measuring and feeding predetermined lengths of wire into said wire-forming assembly, said wire feed means being synchronized with said cutoff assembly and said wire-forming assembly.

13. An apparatus for producing wire clips according to claim 12 including a wire straightener means through which said wire passes prior to being measured, fed and cut, wherein said wire is straightened and any residual stresses are removed.

14. An apparatus for producing wire clips according to claim 1 including a feed means for measuring and feeding wire into said wire-forming assembly, said feed means comprising a follower arm which moves in accordance with a cam means, a first link means having a first end thereof attached to said follower arm and a second end thereof pivotally attached to the first end of a second link means, said second link means pivotable about a point intermediate its ends, a second end of said second link means pivotally attached to a wire hitch assembly, said wire hitch assembly adapted to grip said wire on a feed stroke and to pass along said wire on a return stroke.

15. A means for automatically measuring a length of wire and feeding said length of wire into a wire forming apparatus comprising a cam follower arm having a first and second end, said arm pivotable about said first end thereof, a follower means thereon intermediate said first and second ends adapted to ride on a rotating cam surface, a link means having a first portion connected to said second end of said follower arm, and a second portion thereof connected to a hitch feed assembly, said hitch feed assembly reciprocal between a first position and a second position, movement of said hitch feed assembly from said first position to said second position comprising a feed stroke and movement from said second position to said first position comprising a return stroke, said feed hitch assembly including a gripper means that allows said hitch assembly to grip said wire on said feed stroke and allows said hitch feed assembly to slide over said wire on said return stroke. 16 A means for measuring and feeding according to claim 15 wherein said link means is connected to said follower arm by means of an adjustable clamp which may be moved along and secured to said follower arm, said link means including a first link having a first end attached to said adjustable clamp and a second end attached to a first end of a second link member, said second link member having at least two alternate pivot points intermediate its ends, said second link having its second end connected with said hitch feed assembly.

17. A mEans for measuring and feeding according to claim 16 wherein said wire hitch feed assembly comprises a body portion, said body portion having a projecting portion thereon, said projecting portion having a wire-receiving slot therein, said projecting portion having a gripper member pivotally attached thereto, said gripper member rotatable in the vertical plan which passes through the axis of the wire, said gripper member being of a length so that when said wire is in said slot said gripper member will abut thereagainst.

18. An apparatus according to claim 1 including a cutoff assembly, said cutoff assembly including an upper jaw having a first passageway therethrough adapted to receive said wire, said upper jaw having a first end and a second end, a lower jaw pivotally attached to said upper jaw and said upper jaw first end, said lower jaw having a knife blade portion upstanding therefrom and movable adjacent said second end portion of said upper jaw across said first passageway whereby it cuts off the wire, said lower jaw having a locking pin extending therethrough, a second passageway in said upper jaw intersecting said first passageway, said locking pin having a head movable through said second passageway into and out of said first passageway, said locking pin having a lower base portion below said lower jaw, a biasing means below said base portion biasing said locking pin upwardly so that as said lower jaw swings upwardly into cutting relation with said wire said lower base allows said locking pin to move upwardly against the wire in said passageway to hold it during the cutting of said wire.

19. A method of forming a wire clip comprising gripping a central portion of a cut length of wire, moving said central portion between means for forming opposite ends of said cut length so that said cut length is initially formed by said gripping means on opposite sides thereof, forming a first portion of said cut length of wire on one side of said gripper means with said central portion firmly gripped, partially forming a second portion of said cut wire length on the opposite side of said gripper means, relaxing the gripper means and completing the formation of said second portion of said wire.

20. A method of forming a wire clip according to claim 19 including the step of inserting a grommet means in said completed hook portion as said forming steps are completed and ejecting said completed clip having a grommet therein.

21. A method of forming a wire clip according to claim 17 comprising feeding an end portion of a continuous length of wire through a cutoff assembly having a cutting means and into a wire-forming means, gripping said wire on opposite sides of said cutter means and cutting said wire.

22. A method for forming wire clips according to claim 17 including the step of bending the completed hook at an angle to the central portion of said cut length of wire and ejecting said completed hook from said gripping means with an air blast.