US3747186A

US3747186A - Machine for making wire terminals and applying same to a bobbin

Info

Publication number: US3747186A
Application number: US00188085A
Authority: US
Inventors: J Cervenka; M Hetzel
Original assignee: CERZEL TOOL AND ENG CO
Current assignee: CERZEL TOOL AND ENG CO
Priority date: 1971-10-12
Filing date: 1971-10-12
Publication date: 1973-07-24
Anticipated expiration: 1990-07-24

Abstract

A machine for cutting wire into terminals and applying same to a plastic bobbin which includes means for incrementally and guidably feeding wire to a cutter where the wire is cut into terminal lengths, a bobbin holder adjacent the cutter having terminal holes aligned with the terminals after they have been cut from the wire, means for holding the terminals in aligned relation with the holes of the bobbin and against a backing member, means for connecting the bobbin holder to the feeder so that upon the return stroke of the feeder the terminals are inserted into the bobbin holes, and means for assisting the feeding of the terminals in the bobbin.

Description

United States Patent 1 Cervenka et al.

[ MACHINE FOR MAKING WIRE TERMINALS AND APPLYING SAME TO A BOBBIN 111 3,747,186 July 24, 1973 3,409,972 11/1968 Cervenka et al. 29/203 DT Primary E arqminer-Thomas l-l. Eager Attorney-James B. Kinzer, Lloyd L. Zickert et al.

['75 Inventors: Joseph J. Cervenka, Elmhurst;

Marvin E. Hetzel, Riverside, both 57 ABSTRACT of A machine for cutting wire into terminals and applying 7 1 Assigneez Cemel Tool & Engineering same to a plastic bobbin which includes means for in- Company, Broadview L crementally and guidably feeding wire to a cutter where the wire is cut into terminal lengths, a bobbin [22] Filed: Oct. 12, 1971 holder adjacent the cutter having terminal holes aligned with the terminals after they have been cut [21] Appl' 188085 from the wire, means for holding the terminals in aligned relation with the holes of the bobbin and [52] [1.8. CI 29/203 D against a backing member, means for connecting the [51] Int. Cl. H05k 13/00 bobbin holder to the feeder so that upon the return [58] Field of Search 29/203 D, 203 B, stroke of the feeder the terminals are inserted into the v 2 203 T bobbin holes, and means for assisting the feeding of the terminals in the bobbin. [56] References cued 11 Claims, 18 Drawing Figures UNITED STATES PATENTS 3,266,695 8/1965 Cervenka et al 227/96 [i i1 47 47 3 I H l gig i ill I" 50 1 A5 I mi II i I I i 39 40 o m i 2 l PAIENIED 3.747. 186

sum 1 or 5 INVENTORS JOSEPH J. CERVENKA MARVIN E. HETZEL BY my, 4 W 7W TTORNEYS PATENIEB JUL24 m3 SHEET 2 [IF 5 INV ENTORS JOSEPH J. CERVENKA MARVIN E HETZEL I TTORNEYS PAIENIELJULNIBTS sum 3 or s INVENTORS JOSEPH J, CERVENKA MARVIN E H ETZ E L ATTORNEYS Pmzmwwm 3.147. 186

SHE 5 [IF 5 INVENTORS JOSEPH J. CERVENKA MARVIN E. HETZEL BY 16' A M JW v AT ORNEYS MACHINE FUR MAKING WIRE TERMINALS AND APFILYING SAME T A BGBBIN This invention relates in general to a machine for applying terminals to a plastic bobbin used as a component for an electrical coil, and in particular to a machine capable of successively cutting terminals from wire and inserting the terminals into holes of a bobbin.

The manufacture of electrical components is under constant review for the purpose of reducing costs. This has led to the development of the machine of the present invention, which is capable of producing a plastic bobbin with terminals mounted thereon at a cost lower than heretofore accomplished. The machine of the invention successively cuts lengths of wire to define terminals from wire spools and inserts the cut terminals into holes of a plastic bobbin which is formed by the usual molding methods from a thermosetting plastic, or the like. The holes in the bobbin are round or cylindrical in shape, while the cross section of the wire terminals is rectangular and essentially square. A diagonal of the wire cross section is greater than the diameter of the holes wherein plastic around the holes is gouged or displaced as the terminals are inserted therein and driven home. This provides a terminal mounted on the bobbin which will withstand an acceptable pull value without moving in the bobbin hole. Further, the inserted portion of the terminal will not rotate in the hole when the free end is subjected to rotational force.

The machine of the present invention includes a cutter for cutting the wire into terminal lengths and a wire feeder for incrementally feeding the wire to the cutter. The cutter includes a stationary blade mounted on the die holder of a press and a punch mounted on the punch holder which is movable toward and away from the die holder. Suitable guide means is provided for guiding the wire along predetermined paths to the cutter where it is delivered to a grooved movable pad that coacts with the punch to catch and support the cut terminals when they are inserted into the terminal holes of the bobbin. A bobbin holder maintains the bobbin in a position so that the bobbin holes align with the cut terminals when the punch is at the end of the punch stroke. The bobbin holder is mounted on the wire feeder so that upon the return stroke of the wire feeder the bobbin holder will cause the bobbin to move toward the terminals and insert the terminals into the bobbin terminal holes. Power means is provided to assist the setting of the terminals in the bobbin and thereafter the return stroke of the punch causes the bobbin to be ejected from the bobbin holder by virtue of spring means returning the pad to its upper position for receiving the next successive set of terminals. The bobbins are inserted by hand into the bobbin holder after which the cycle of feeding the wire an incremental amount, cuttingthe wire to form the terminals, inserting the terminals into the bobbin, and ejecting the bobbin with the terminals from the bobbin holder completes one cycle of operation.

It is therefore an object of the present invention to provide a machine capable of assembling terminals with a bobbin at a cost lower than heretofore known.

It is another object of this invention to provide a machine for cutting terminals from wire and inserting the terminals into bobbin holes of a bobbin.

Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts, in which:

FIG. 1 is a front elevational view of a machine according to the invention, which is capable of cutting terminals from wire and mounting same on a bobbin;

FIG. 2 is an end elevation view of the machine of FIG. 1 with some parts omitted and looking at the end having the wire cutter;

FIG. 3 is a top plan view of the machine with some parts in section and taken generally along Line 33 of FIG. 2, while showing some parts broken away for purposes of clarity;

FIG. 4 is an enlarged detail sectional view taken substantially along Line 4-4 of FIG. 3;

FIG. 5 is an enlarged detail elevational view of the wire feeding clamp taken substantially along Line 55 of FIG. 3;

FIG. 6 is a partially fragmentary enlarged detail sectional view taken substantially along Line 6-6 of FIG. 3;

FIG. 7 is an enlarged detail sectional view taken substantially along Line 77 of FIG. 2;

FIGS. 8, 9 and 10 are enlarged detail axial sectional views taken through the die holder illustrating somewhat diagrammatically the steps of cutting the terminals from the wire, inserting the terminals in the bobbin and advancing the terminal wire to. the cutter;

FIG. 11 is a greatly enlarged detail sectional view taken substantially along Line l1-l1 of FIG. 8;

FIG. 12 is a fragmentary enlarged top plan view of the movable pad;

FIG. 13 is a perspective view of a bobbin with terminals mounted thereon in accordance with the machine of the present invention;

FIG. 14 is a front elevational view of the bobbin and terminal assembly looking at the terminal end thereof;

FIG. 15 is a side elevational view of the terminal and bobbin assembly of FIG. 13;

FIG. 16 is-a vertical sectional view of the bobbin and terminal assembly taken substantially along Line 16-16 of FIG. 14;

FIG. 17 is a greatly enlarged end elevational view of a terminal and a terminal hole of a bobbin illustrating the terminal in mounted position relative the terminal hole; and

FIG. 18 is an enlarged detail sectional view taken substantially along Line 1818 of FIG. 17.

Referring now to the drawings, the machine of the invention as illustrated in FIGS. 1 and 2, and generally designated by the numeral 20, forms terminals from strands of wire and inserts the terminals into terminal holes of a bobbin to define a bobbin and terminal assembly 21 illustrated in FIGS. 13-18 which may be thereafter processed to form an electrical component.

A bobbin and terminal assembly 21 includes a bobbin 22 molded from a suitable thermosetting plastic and a plurality of terminals 23. The bobbin 22 is illustrated in FIG. 14 prior to the insertion of the terminals 23. The bobbin 22 includes a body 24 and a pair of

terminal bars

25 and 26. Each of the terminal bars have a plurality of equally spaced-apart terminal holes 27, the terminal bar 25 having a total of five holes, while the terminal bar 26 has a total of seven holes. It should be appreciated that any number of terminal holes will be provided as needed for a particular application. The terminal holes 27, as particularly illustrated in FIG. 17, are

circular in cross-section and terminate at a suitable depth which will allow the terminals to be inserted and anchored to withstand a prescribed pull test. As also illustrated in FIG. 17, the cross-section of the terminals 23 is square and the diagonals of the cross-section is greater than the diameter of the terminal holes whereby insertion of the terminals into the terminal holes causes a gouging or displacement of a plastic material at the four corners of the terminal thereby wedging the terminals tightly in the terminal holes when they are inserted and seated. The terminals are inserted to a depth not quite the full depth of the hole since the gouging of the hole wall causes plastic shavings to be accumulated at the inner end of the terminal and a sufficient space must be provided between the terminal ends and the bottom of the hole to accommodate the plastic shavings which are indicated by the numeral 28 in FIG. 18. Inasmuch as the terminal bar 26 is provided with more terminal holes than the terminal bar 25, a notch 260 on the terminal bar 26 indicates to the operator the orientation of the bobbin as it is to be inserted into the machine.

The machine 20 generally includes a base or die holder 35, a punch holder 26 movable toward and away from the die holder, a cutter 37 for cutting the wire into lengths to define terminals, a wire feeder 38 for incrementally feeding wire to the cutter 37, a bobbin holder 39 for holding the bobbin and moving it onto the terminals when the terminals are inserted into the terminal holes of the bobbin, and a helping cylinder 40 for driving the bobbin home on the terminals after the bobbin has been initially advanced onto the terminals by the bobbin holder 39.

The die holder 35 and the helping cylinder 40 are mounted together on a base plate 41 and the die holder includes a die holder plate 42 which supports the cutter 37, the wire feeder 38, the bobbin holder 39 and the punch holder 36 with its associated components. The punch holder 36 includes a punch plate 43 that is driven toward and away from the die holder plate 42 by a hydraulic cylinder 44 which is supported on a plurality of upstanding posts 45 extending from the die plate 42 and upwardly through holes in the punch plate 43. A piston rod 46 is connected to the punch plate 43. A plurality of conventional press guides 47 extend vertically and serve to vertically guide movement of the punch plate 43 with respect to the die holder plate 42.

Each vertical guide includes a lower tubular member 48 within which telescopes an upper stud 49, and a ball bearing sleeve (not shown) is arranged between the stud and tubular member. The punch plate 43 is allowed to descend to the die holder plate 42 a predetermined distance as gauged by a plurality of stop bars 50.

A punch is mounted on the punch plate 43 and defines a part of the cutter 37 in that it includes a cutting edge 56 coacting with a cutting edge 57 of a stationary blade 58 carried on the punch holder blade 42, FIGS. 8 to 10. Thus, the cutter 37 is comprised of the punch 55 and the stationary blade 58.

A plurality of strands of wire 60 are incrementally fed to the cutter 37 by the wire feeder 38 which is essentially a standard commercially available feed mechanism designated Rapid-Air Model A-2" manufactured by Mechanical Tool and Engineering Company, Rockford, Ill. The feed mechanism includes a feed clamp 64 movable along the die holder plate 42 to grip the wire, move the wire through a feed stroke an incremental distance, ungrip the wire and return for a successive cycle of feed, and a stock clamp 65 for gripping the wire during the return stroke of the feed clamp 64 to prevent back sliding of the wire 60.

The feed clamp 64 (FIG. 5) includes a base 66 having a wire jaw 67 and an upper movable bar 68 having a movable wire jaw 69, it being appreciated that when the upper jaw 69 is brought downwardly into engagement with the wire 60 the wire is clamped in place for a feed operation, as shown in FIG. 10, and when the jaw 69 is disengaged from the wire 60, the wire clamp is in position for the return stroke. Assisting the disengagement of the movable jaw 69 from the wire are a pair of leaf springs 70. Pneumatic cylinders which are double-acting (not shown) serve to bring the upper movable jaw 69 into clamping relation with the wire 60. Preferably, the surfaces of the

jaws

67 and 69 are roughened to enhance the gripping relation with the I wire 60.

A stock clamp 65 (FIG. 6) includes a base 71 having a jaw insert 72 and an upper movable clamping bar 73. Double acting pneumatic cylinders (not shown) operate a stock clamp to drive the clamp bar 73 into and out of clamping engagement with the wire 60 during the cycling of the feed mechanism. A further pneumatic cylinder (not shown) drives the feed clamp 64 along the die holder plate 42 during the feed and return strokes. It should be appreciated that the operation of the feed mechanism, including the feed clamp 64 and the stock clamp 65, is synchronized to define incremental feeding of the wire to the cutter 37 and to prevent backsliding of the wire during the return stroke of the feed clamp so that the proper length of wire is always presented at the cutter to give the same exact terminal size for each cycle of operation. It will also be appreciated that the feed stroke of the wire will be accomplished when the punch plate is in its upper position so that the punch is not in any interfering position with the advance of the wire.

The wire 60 as it is advanced to the cutter 37 is advanced through wire grooves 75 formed in a guide plate 76 which coacts with the base 71, as seen particularly in FIG. 11. The wire grooves 75 are sized to be slightly larger than the cross-section of the wire strands so that the wire will move therethrough but will be constrained in a predetermined path. Therefore, the wire strands as they emerge from the end of the guide plate 76 will be in accurately spaced relation to each other.

When the strands of wire are incrementally advanced by the feed mechanism from the end of the guide plate 76, they must be ready for the cutting and orienting of the cut lengths to thereafter be placed in register with the terminal openings of the bobbin. To assist in bringing the wire strands 60 into the wire feeder and thereafter into the guide plate 76, a first guide plate 80 is'provided at the entrance end of the machine for properly orienting the strands of wire relative each other as they are taken from spools which are suitably mounted adjacent to the machine and which hold a supply of wire sufficient to make a large quantity of terminals. The guide plate 80 is suitably mounted on the die holder plate 42 by means of a mounting arrangement 81. The holes 82 formed in the guide plate 80 are triangular in cross-section with the bottom side being horizontally arranged wherein the holes assist in orienting the strands of wire to square them away with respect to their cross-section.

Following the ejecting of the ends of the wire strands from the final guide plate 76, the strands are directed into grooves 85 formed in a movable pad 86 (FIGS. 3, 7, 8-10 and 12). The grooves 85 open upwardly and have a depth slightly less than the height of the wire strands so that the wire strands project slightly above the upper surface of the movable pad. The mouth of the grooves 85 are flared at 85a for the purpose of assisting in the guiding of the ends of the wire strands into the grooves as they are being advanced by the feed mechanism, it being appreciated that the movable pad 86 is in its upper position as illustrated in FIG. when the strands of wire are being incrementally advanced to the cutter. As seen particularly in FIGS. 3 and 7, the oppositeupstanding sides of the movable pad 86 are formed with rectangular portions 87 which slide in vertical tracks 88 formed in the base 71. Suitable means is provided for stopping the upward travel of the movable pad at a point where the bottoms of the grooves 85 register with the top surface 71a of the base 71. The movable pad 86 is biased to its upper position by a spring 89. The movable pad functions as a part of a holder for the cut lengths of wire and coacts with the punch 55 as it descends and cuts the wire, as seen particularly in FIGS. 8 and 9. Accordingly, the wire when it is cut defines terminals which are gripped by the movable pad 86 and the punch 55 and held in position at the bottom of the stroke of the punch in registry with the terminal holes of the bobbin held by the bobbin holder 39.

The bobbin holder 39 includes a block 92 formed with a step 93 to receive one of the terminal bars. The top surface of the block, identified as 94, provides a seat for the body portion of the bobbin while the step 93 provides a seat for one of the terminal bars. The depth of the step 93 is approximately equal to the depth dimension of a terminal bar so that the face of the terminal bar in which the terminal holes are formed is coplanar with the face 95 of the bobbin holder base 92. A pair of spring biased jaws 96, FIG. 3, are mounted on the bobbin holder and terminate at their outer ends in cut terminals 23 held by the punch and movable pad.

As seen most clearly in FIGS. 8, 9 and 10, the bobbin holder 39 is connected to one end of a slide 100, the other end of which is connected to the movable feed clamp 64 of the feed mechanism whereby the bobbin holder is cycled simultaneously with the feed clamp 64. Therefore, the return stroke of the feed clamp 641 will drive the bobbin 21 into the cut terminals 33 so that the terminals are inserted into the terminal holes of the bobbin. The face 101 of the base 71 functions as a backing stop member for the ends of the terminals during the terminal insertion step. Similarly, the step 93 provides a backing stop member for the terminal bar.

In order to fully seat the terminals at the prescribed depth in the terminal holes, the helping cylinder 40 having a plunger 105 is actuated at the conclusion of the return stroke of the feed clamp 64 wherein the plunger 105 engages the block 92 of the bobbin holder 39, as seen in FIG. 8, to drive the bobbin holder home the last incremental distance of travel, which may be in the neighborhood of one sixty-fourth inch to properly seat the terminals in the terminal holes. Thus, as soon as the bobbin holder 39 has completed its terminal insertion stroke, the helping cylinder 40 will be energized to complete terminal insertion.

Following the insertion of the terminals in the terminal holes of the bobbin, the punch plate 43 is driven upwardly to its upper position taking the punch 55 therealong which coacts with the spring biased movable pad 86 to eject the terminal and bobbin assembly from the bobbin holder by virtue of applying a force to the bobbin through the terminals 23. At the conclusion of the return stroke of the punch, the feed mechanism is then again energized to advance the strand of wires an incremental distance equal to the length of the terminals for the next successive cycling of the cutting and inserting operation.

It will be appreciated that suitable instrumentation and controls will be provided for sequentially operating the feed mechanism, the punch and the helping cylinder in timed relation in order to obtain the desired operation as heretofore described.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of the appended claims.

The invention is hereby claimed as follows:

1. A machine for cutting wire into a short length to define a terminal and inserting the terminal into a terminal hole of a bobbin comprising, a die holder, a punch holder coacting with the die holder movable toward and away from the die holder, said die holder having wire guide groove means for guiding wire along a predetermined path, a wire feeder on the die holder to incrementally feed the wire to a cutter during the feed stroke, said cutter including a fixed blade on the die holder and a punch on the punch holder, a movable pad on the die holder adjacent the cutter having wire groove means for receiving the terminal wire and coacting with the punch to hold the cut terminal during insertion of same into a terminal hole of the bobbin, said pad including means for normally urging same to an upper position where the wire groove means thereof aligns with the wire at the cutter, and a bobbin holder movable with the wire feeder to move the bobbin onto the cut terminal during the return stroke of the wire feeder.

2. A machine as defined in claim 1, wherein the mouth of the pad wire groove means is flared to assist in guiding the wire therein.

3. A machine as defined in claim I, wherein said punch and pad through the terminal inserted in the bobbin ejects the bobbin from the holder upon the return stroke of the punch.

4. A machine as defined in claim 1, and means assisting movement of the bobbin holder to seat the terminal in the bobbin.

5. A machine as defined in claim 1, wherein means is provided in conjunction with the feeder to prevent back-sliding of wire during the return stroke of the feeder.

6. A machine for successively cutting a plurality of strands of wire into short lengths to define terminals for an electrical component and inserting the terminals into terminal holes of a bobbin, said machine comprising a stationary die holder, a punch holder coacting with the die holder and cyclically movable toward and away therefrom, a wire cutter including a stationary cutting edge on the die holder and a punch on said punch holder, wire guide groove means on the die holder for guiding the wire along predetermined paths to the cutter, a wire feeder on the die holder incrementally feeding the wire therealong to the cutter so that cycling of the punch holder cuts predetermined lengths of wire into terminals, a movable pad at the cutter having wire grooves opening upwardly to guidably receive the wire as it is fed to the cutter and coacting with the punch to hold and support the cut lengths of wire at the bottom of the cutting stroke, said pad being spring biased to an upper position where the wire grooves of the pad are aligned with the wire at the cutter, a bobbin holder adjacent to the pad constraining under light spring pressure a bobbin with terminal holes so that the terminal holes are aligned with the wire when the punch and pad are in their lower position supporting the wire, means connecting the bobbin holder to the wire feeder whereby the return stroke of the feeder causes the bobbin to be forced onto the terminals to insert the terminals into the terminal holes, and power assist means for engaging the bobbin holder at the end of the terminal insertion stroke to seat the terminals in 8 the bobbin.

7. A machine as defined in claim 6,' wherein the cross-section of the terminal holes in the bobbin is round and the cross-section of the wire is square with the diagonals being greater than the diameter of the holes.

8. A machine as defined in claim 7, wherein said pad and punch on the return stroke of the punchcoact through the terminals to overcome the spring pressure of the bobbin holder and eject the terminal and bobbin assembly therefrom.

9. A machine as defined in claim 8, wherein the mouth of the pad wire groove means is flared to assist in guiding the wire therein.

10. A machine as defined in claim 8, wherein means is provided in conjunction with the feeder to prevent back-sliding of the wire during the return stroke of the feeder. I

11. A machine as defined in claim 8, wherein the mouth of the pad wire groove means is flared to assist in guiding the wire therein, and wherein means is provided in conjunction with the feeder to prevent backsliding of the wire during the return stroke of the feeder. f

a: a k t k

Claims

3. A machine as defined in claim 1, wherein said punch and pad through the terminal inserted in the bobbin ejects the bobbin from the holder upon the return stroke of the punch.

6. A machine for successively cutting a plurality of strands of wire into short lengths to define terminals for an electrical component and inserting the terminals into terminal holes of a bobbin, said machine comprising a stationary die holder, a punch holder coacting with the die holder and cyclically movable toward and away therefrom, a wire cutter including a stationary cutting edge on the die holder and a punch on said punch holder, wire guide groove means on the die holder for guiding the wire along predetermined paths to the cutter, a wire feeder on the die holder incrementally feeding the wire therealong to the cutter so that cycling of the punch holder cuts predetermined lengths of wire into terminals, a movable pad at the cutter having wire grooves opening upwardly to guidably receive the wire as it is fed to the cutter and coacting with the punch to hold and support the cut lengths of wire at the bottom of the cutting stroke, said pad being spring biased to an upper position where the wire grooves of the pad are aligned with the wire at the cutter, a bobbin holder adjacent to the pad constraining under light spring pressure a bobbin with terminal holes so that the terminal holes are aligned with the wire when the punch and pad are in their lower position supporting the wire, means connecting the bobbin holder to the wire feeder whereby the return stroke of the feeder causes the bobbin to be forced onto the terminals to insert the terminals into the terminal holes, and power assist means for engaging the bobbin holder at the end of the terminal insertion stroke to seat the terminals in the bobbin.

7. A machine as defined in claim 6, wherein the cross-section of the terminal holes in the bobbin is round and the cross-section of the wire is square with the diagonals being greater than the diameter of the holes.

8. A machine as defined in claim 7, wherein said pad and punch on the return stroke of the punch coact through the terminals to overcome the spring pressure of the bobbin holder and eject the terminal and bobbin assembly therefrom.

10. A machine as defined in claim 8, wherein means is provided in conjunction with the feeder to prevent back-sliding of the wire during the return stroke of the feeder.

11. A machine as defined in claim 8, wherein the mouth of the pad wire groove means is flared to assist in guiding the wire therein, and wherein means is provided in conjunction with the feeder to prevent backsliding of the wire during the return stroke of the feeder.