US2915616A

US2915616A - Wire bender and connector

Info

Publication number: US2915616A
Application number: US772228A
Authority: US
Inventors: John T Griffin
Original assignee: Clevite Corp
Current assignee: Clevite Corp
Priority date: 1958-11-06
Filing date: 1958-11-06
Publication date: 1959-12-01
Anticipated expiration: 1976-12-01

Description

Dec. l, 1959 J. T. GRIFFIN 2,915,616

WIRE BENDER AND CONNECTOR Filed Nov. 6, 1958 6 Sheets-Sheet 1 ATTORNEY Dec. 1, 1959 J. T. GRIFFIN WIRE BENDER AND CONNECTOR 6 Sheets-Sheet 2 Filed Nov. 6, 1958 inf Vfl/Iliff! AT ORNEY Dec. l, 1959 .1.7. GRIFFIN 2,915,615

WIRE BENDER AND CONNECTOR Filed Nov. e, 195e e sheets-sheet s INVI'NTOR.-

JOHN T.GRIFFIN ATTORNEY Dec. 1, 1959 J.r.GR|FF1N 2,915,615

WIRE BENDER AND CONNECTOR Filed Nov. 6, 1958 6 Sheets-Sheet 4 INVENTOA JOHN T. GRIFFIN ATTCRNEY I Dec. 1, 1959 J. T. GRIFFIN 2,915,616 NDER AND coN Filed Nov. 6, 1958 6 Sheets-Sheet 5 2,915,616 Patented Dec. 1, 1959 United States PatentOifice WIRE BENDERr AND YCONNECTOR John T. Griffin, Waltham, Mass., assignor to Clevite Corporation, Cleveland, Ohio, a corporation of Ohio This invention pertains to a vmachine for making and vconnecting a` U-shaped spring member, to a mounting wire. As an example a U-shapedspring contact is connect'ed to an electrical conductor wire. lThe U-shape provides the desired spring action and also provides relatively large area of electrical contact for small electronic devices such as diodes.

In the manufacture of silicon diodes it has been found necessary for optimum results to connect a U-shaped length of platinum-iridium wire or ribbon to the anode lead thereof. This length of ribbon isspot Welded to a small round piece of dumet wire which is only .02" in diameter, and the location of the substantially U- shaped piece of ribbon with respect to a glass bead on the dumet wire must be very carefully controlled.

An object of the present invention is to provide a f machine for and a method of connecting a very small U-shaped piece of ribbon to a very small wire with very close tolerances.

Another object of the invention is to provide a machine for and a method of continuously and automatically connecting U-shaped piecesof ribbon to lengths of wire.

For a better understanding of the present invention, together with other andl further objects thereof, reference is had to the following description taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

In the drawings:

Figure 1 is an isometric view, very greatly enlarged, of the anode lead for a silicon diode after the U-shapcd ribbon has been connected thereto.

Figure 2 is a planV view looking down on the equipment for cutting andvshaping the ribbon shown in Figure 1, and for connecting the shaped ribbon to the length of wire which forms part of the anode lead.

Figure 3 is a side view of the machine shown in Figure 2.

Figure 4 is an enlarged side'view of the portion of the machine called a loading wheel.

Figure 5 is a fragmentary view of one of the many loading slots carried by the loading wheel.

Figure 6 is an enlarged end view showing the loading wheel, the mechanism for loading it, and the mechanism for unloading the formed and connected anode leads.

Figure 7 is a plan view of the ribbon feeding and forming heads with their top covers removed.

Figure 8 is a sectional view taken along line 8 8 of Figure 7.

Figure 9 is a sectional view taken along line 9 9 of Figure 7.

Figure l0 is a greatly enlarged fragmentary plan view showing the ribbon forming head in one of its positions, and

Figure ll is similar to Figure 10 showing the ribbon forming head in a subsequent position.

With reference to Figure l, there is shown an anode lead for a silicon diode comprised of a length of dumet wire 10 which is about .02 inch in diameter, a glass bead 11 secured to the wire 10, and a substantially U-shaped ribbon 12 spot welded to the Wire 10 at a location close to the bead. The ribbon 12 is made of platinum-indium material and it is about .02 inch wide. It will be appreciated that to secure the ribbon 12 to the wire 10 on a mass production basis land to hold positional tolerances of approximately .003 is a difficult task.

The machine for forming the ribbon into its U-shape and for securing the shapedv ribbon 12 to the wire 10 is shown in its entirety in Figures 2 and 3. It is comprised of a motor 13 which, through a speed reduction gear 14, drives a one-revolution clutch 15. A foot treadle device 16 controls the application of power from the motor 13 to the main drive shaft 20 which is mounted in

bearings

18, 22, -23 and 9. Loosely positioned around the main driveshaft 20 there is a sleeve or spacer device 17 located adjacent bearing 18 and holding gear 19 in place.

The main drive shaft 20 rotates a cam 24 and through a cam follower 25 operates a front welding electrode device 26. The drive shaft 20 also drives a gear device 27 which in turn rotates a drive shaft 28 mounted in

bearings

29, 30. The drive shaft 28 operates a welding control cam 8 which in turn operates a switch 30 in timed relation to motions of other parts of the machine. The drive shaft 28 also rotates cam 31 and through cam follower 32 operates a slide 33 for indexing and rotating a loading wheel 34, shown in detail in Figure 4.

The drive shaft- 21 is mounted in

bearings

35, 36, and it rotates cam wheel 37 which through follower 38 actuates a ribbon forming slide 39. Also, shaft 21 rotates cam wheel 40, and through the cam follower 41 actuates a ribbon clamp slide 42. Drive shaft 21 through the gear mechanism 43 drives the `drive shaft 44 which is mounted in

bearings

45, 46.

Drive shaft 44 rotates cam 47 and through follower 48 actuates the tape feed head 49 which pulls the tape 12 from a supply reel 50, stop-dog 51 being provided to prevent the tape from being pulled back out of the forming head 49. Drive shaft 44 also rotates cam wheel 52 for actuating the rear welding electrode 60 through cam follower 53, and the drive shaft 44 rotates cam wheel 55 which, through follower 56, actuates an indexing pin 57 for indexing and holding the loading wheel 34.

By the use of a single drive motor 13 and

multiple drive shafts

20, 21, 28, 44, all driven from the single motor, the timing of various sequential steps is greatly simplified. Also, by making the position of each of the

cam mechanisms

24, 29, 31, 37, 40, 47, 52 and 55 adjustable with respect to their respective drive shafts flexibility is inherent in the machinel and accurate adjustment of the numerous motions may be made.

ln the operation of the machine the loading wheel 34 is rotated on bearings 61, 62 (Figure 6) by means of the wheel driving cam 31, the cam follower 32 (see Figure 4) and the loading wheel pawl slide 33. The pawl slide 33 is connected to an actuating member 64 by pin 65 extending through slot 66 which provides for a certain amount of lost motion and adjustment if needed, and a spring 67 is positioned between the end of the pawl slide 33 and the actuating member 64. The actuating member 64 is mounted between slides 68, 69 and carries with it a pawl 70 which is upwardly biased by spring 71 into engagement with ratchet teeth 72 forming part of loading wheel 34. For each revolution of the cam 31 the loading wheel 34 is rotated by an amount equal to one tooth 72.

As the loading wheel 34 rotates each of its plurality of loading lslots 74 (see Figure 5) passes a loading magazine 75 (see Figure 6), and after the wheel 34 makes substantially a full revolution each loading slot passes an ejecting. mechanism 76 which ejects eachl successive assembled anode lead into a receiving magazine 77. While the anode devices are in the loading magazine 75 they are in an unassembled condition and consist of the wire 10 and the glass bead 11; and when they are ejected from the wheel 34 they have been assembled and consist of the wire 10, the bead 11 and the U- shaped member 12. While each anode device is held in the loading wheel 34 a U-shaped member 12 is connected to one end of the wire 10.

As shown in Figure 4 the ejector device 76 may be positioned at the top of the wheel 34, and, somewhere to the side of the ejector, the loading magazine may be positioned for inserting into each empty yslot 74 as it passes one unassembled anode device made up of the wire 1) and glass bead 11. As wheel 34 is rotated in a clockwise direction by the pawl 70 an arcuate positioning device 79 holds the anode devices in place. As each loading slot reaches the forming head 39 a proper length of ribbon 12 is cut off, formed to the proper shape and spot welded to the protruding length of wire 10', establishing the end 12. The nished assembly then travels around to the ejector mechanism 76 where it is discharged from the loading wheel 34 into the receiving magazine 77.

The mechanism for indexing the ribbon into the forming head 39 comprises the ribbon feed head 4,9, shown in enlarged detail in Figures 7, 8, 9. The ribbon 12 is positioned in the slot 80 which extends completely through the ribbon feed head 49 and into the ribbon forming slide 39. As shown in Figure 7, the ribbon feed head 49 is in its retracted, or outermost position,

and the end of the ribbon is located at point 86 (Figure l). From this position the ribbon clamp cam 40, through cam follower 41, moves the ribbon clamp slide 42 forward, clamping the ribbon section 12 against the back face 81 of the ribbon feed head 49. Thereafter cam 47, through follower 48, moves the entire ribbon feed head 49 toward the loading wheel 34, pulling a length of ribbon 12 with it, and positioning the ribbon in the forming head 83, shown at the bottom of Figure 7, and shown in greatly enlarged detail in Figure l0. Thereafter, and while the ribbon is still clamped by the ribbon clamp slide 42, cam 37, through follower 38, moves the forming slide 39 forward, causing the knife edge 85 thereof (Figure l0) to sever the'ribbon 12 against the lower edge 86 of the back face 83 of the forming head 83. Simultaneously with the severing of the ribbon a plunger 90, which is biased forwardly by spring 91, presses the central portion 94 of the severed length of ribbon against the raised forming die 95 which is mounted on the support 96. Substantially simultaneously therewith, the forward motion of the forming head S3 causes the two side portions thereof 97, 98 to engage the severed ribbon on either side of the firmly held central portion 94, and to fold them back around the die 95 in a direction toward the anode wire 10. Thereafter the front and

back welding electrodes

100, 101 are indexed toward the glass beaded anode lead, and engage the ends of the severed ribbon 12 completing the process of folding the ribbon ends around the wire 10. The spot welding electrodes i), 101 clamp the ribbon 12 against the wire 10 and at that instant the -cam 29 (Figure l) causes the electrical switch to energize the

electrodes

100, 101 to spot weld the ribbon section to the wire 10. This final position is shown in Figure l1. Thereafter the electrodes back off, the forming head 83 backs off and the knife edge 85 is withdrawn. At the same time the ribbon clamp slide 42 releases its grip on the ribbon 12, and thereafter the ribbon feed head 49is retracted. The stop-dog 51 prevents the ribbon 12 from retracting with the feed head 49, thereby, in eiect, advancing the ribbon wth'respect to the feed head.

As shown in Figure 2, the cam wheel 55 and follower 56 actuate a locating pin 57 in timed relation to the other motions of the machine. Figure 6 shows the details of this mechanism, and in addition show how the same mechanism actuates the ejector 76 for taking the assembled anode leads out of the loading wheel 34 and for transferring them to the receiving magazine 77, The rear plate 34 of the wheel 34 has a plurality of indexing holes in it, one for each loading slot 74. The ratchet mechanism 70, driven by cam 31, roughly positions the loading wheel 34, and at the proper instant, determined by cam wheel 55, the arm 111 which is connected to cam follower 56 and which is pivotally mounted at 112, causes the indexing pin 57 to enter one of the locating holes 110 in the wheel 34. Thus the wheel 34 and the anode lead to be assembled are accurately positioned with respect to the wire forming head. The motion of arm 111 causes the ejector arm 76 to push one of the assembled anode leads out of its slot 74 into the receiving magazine 77.

While there have been described what are at present considered to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modications may be made therein without departing from the invention, and it is, therefore, aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

I claim:

1. A machine for shaping and applying a loop of ribbon to the end of a length of wire, which comprises wire holding means for holding and positioning the end of said length of wire in an indexed location, ribbon feeding means for indexing a length of said ribbon adjacent the indexed end of said wire, ribbon cutting means operative upon said ribbon being indexed adjacent said wire for severing a given amount of said length of ribbon, ribbon forming means operative after said given amount has been severed for shaping said severed length into a loop and for positioning the ends of said ribbon adjacent to and aligned with the end of said wire, spot welding means operative thereafter to hold the ends of said ribbon against said wire and for spot-welding said ribbon and wire together in said position, motor means, and cam means driven by said motor means and actuating the aforesaid wire holding means, ribbon feeding means, ribbon cutting means, ribbon forming means and spot welding means in timed relation to each other.

2. A machine as set forth in claim l, further characterized by said wire holding means comprising a loading wheel having a plurality of loading stations, a loading magazine associated with said wheel for loading a station as said station passes said loading magazine, a discharge magazine for receiving assembled wires from said loading wheel, means for ejecting said assembled wires one at a time from said loading wheel to said discharge magazine, and wheel rotating means driven by said motor means in time relation to the motion of the aforesaid cam means.

3. A machine as set forth in claim 2, further characterized by said wheel rotating means including ratchet means for moving said loading wheel with a step-by-step motion.

4. A machine as set forth in claim 3, further characterized by a locking pin actuated in conjunction with said ejector mechanism for locking said loading wheel in a fixed position while said loop of ribbon is spot-welded to said wire.

5. A machine as set forth in claim 2, further characterized by an electric switch actuated by said cam means for energizing said spot welding means in timed relation.

6. A machine for shaping a length of ribbon into substantially a U-shape and for securing it to opposite sides of a length of wire, comprising an endless loading wheel having a plurality of loading stations, means for loading a length of wire into each station there to be held in fixed position, means for rotating said loading wheel step-by-step one station at a time, forming means for shaping a length of said ribbon into substantially a U-Shape and for spot-welding it onto a length of wire held in said loading wheel, a locking Wheel in indexed position during said spot-Welding operation, and an ejector mechanism interconnected with said locking pin for ejecting a previously assembled wire while said locking pin is moving into said locking position.

7. A Vmachine as set forth in claim 6, further characterized by a single motor means, and cam means driven by said motor means for driving said loading wheel, said forming means,said locking pin and said ejector mechanism in timed relation.

pin for holding said loading 5 6 8. A machine as set forth in claim 7, further characterized by said cam means comprising separate cams for said loading wheel and said forming means and a single cam for actuating both said locking pin and said ejector mechanism.

References Cited in the file of this patent UNITED STATES PATENTS 2,103,206 Ober Dec. 21, 1937 2,840,886 Grube et al. July 1, 1158 2,846,561 Pityo Aug. 5, 1958