US3804317A

US3804317A - Wiping anvil assembly for bending component leads

Info

Publication number: US3804317A
Application number: US00201737A
Authority: US
Inventors: J Gelzer
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-11-24
Filing date: 1971-11-24
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16

Abstract

Apparatus is provided for bending of leads or terminals of electric circuit components such as when assembled with a mounting board of the printed circuit board type. This apparatus includes a driving head adapted to be supported for reciprocating movement axially of the unbent component lead and a wiping anvil interposed between the driving head and component lead and pivotally supported on a collar which is mounted on the driving head for axial reciprocating movement. The anvil is normally disposed in angular relationship to the axis of movement to provide an initial bending of the component lead as the assembly is displaced toward the component lead with the driving head subsequently bearing against the anvil to complete the bending operation by pivoting of the anvil as a consequence of relative reciprocating movement of the anvil supporting collar and driving head. The apparatus is capable of effecting an angular bend of greater than 90*.

Description

United States Patent Gelzer [451 Apr. 16, 1974 Primary Examiner--Granville Y. Custer, Jr. Attorney, Agent, or Firm-William V. Miller [5 7 ABSTRACT Apparatus is provided for bending of leads or terminals of electric circuit components such as when assembled with a mounting board of the printed circuit board type. This apparatus includes a driving head adapted to be supported for reciprocating movement axially of the unbent component lead and a wiping anvil interposed between the driving head and component lead and pivotally supported on a collar which is mounted on the driving head for axial reciprocating movement. The anvil is normally disposed in angular relationship to the axis of movement to provide an initial bending of the component lead as the assembly is displaced toward the component lead with the driving head subsequently bearing against the anvil to complete the bending operation by pivoting of the anvil as a consequence of relative reciprocating movement of the anvil supporting collar and driving head. The apparatus is capable of effecting an angular bend of greater than 90.

10 Claims, 10 Drawing Figures PAIENTEDAPRIBW 3,804,317

sum 1 BF 3 35 INVENTOR.

26 26 JOHN R. GELZER PAIENIED I 3804.317

Q SHEET 2 BF 3 FIG. 4 FIG. 5 FIG. 6

INVENTOR. JOHN R. G'ELZER BY MAHONEY, MILLER 8 TEBENS BY W49 ATTORNEYS PATENTED 61374 3,804.31!

sum 3 OF 3 IN VE NTOR.

JOHN R. GELZER MAHONEY, MILLER STEBENS WQM;

ATTORNEYS WIPING ANVIL ASSEMBLY FOR BENDING COMPONENT LEADS BACKGROUND OF THE INVENTION Assembly and mechanical interconnection of electrical components with mounting boards provided with an electrical circuit printed thereon has heretofore required a substantial amount of hand or manual operations to bend the component leads into mechanical engagement with the electrical circuit prior to a soldering operation. Mechanization of this operation has not proven successful with prior art apparatus in that the several component leads must be bent in relatively different directions to form the best mechanical contact with the printed circuit. Even the several leads of a single component may require bending in relatively different directions. Prior art apparatus utilized for this operation has either comprised a plate movable transversely of'the component leads and parallel to the surface of the printed circuit board which is only capable of bending all leads in the same direction or a relatively complex mechanism involving movement of parts thereof in more than one direction. The latter mechanisms while capable of being constructed to accomplish the objective have proven to be extremely costly and, through lack of versatility and adaptability to different circuits and components, not economically feasible.

BRIEF DESCRIPTION OF THE INVENTION Apparatus of this invention is of a mechanically simple construction and operation but is capable of utilization in bending of individual component leads in a preferred direction for optimum mechanical contact with the printed circuit. The apparatus comprises a wiping anvil assembly which is adapted to be supported for movement in a single direction relative to a component lead with several of the assemblies being mountable on the same support for simultaneous bending of the several respective leads in their respectively preferred directions. Each wiping anvil assembly may be constructed in a relatively small physical size as to be noninterferring with respect to other assemblies and to ad jacent component leads, thus permitting mounting of several assemblies on a single support.

A wiping anvil assembly comprises a driving head adapted for mounting on a support for reciprocating axial movement relative to an unbent axially projecting component lead and a wiping anvil mounted on the driving head for relative axial movement. Displacement of the assembly toward a component lead first brings the anvil which is normally inclined to the axis of movement into contacting engagement with the lead and further axial movement will initiate bending. Relative reciprocation of the anvil and driving head is initially resisted by a spring biasing the head and anvil to a normal position. The anvil is pivotally mounted on a collar or bracket and when the bracket engages the printed circuit board, the anvil and collar will move axially relative to the driving head in opposition to the biasing spring and result in swinging of the anvil to complete the bending operation. Thus, the bending operation only requires a single direction of movement with appropriate configuration of the driving head in cooperation with mounting of the anvil enabling bending of a component lead through an arc of at least 90. Bending of the component lead in a desired direction can be readily accomplished by positioning the assembly on the support in an appropriate relative orientation to the desired direction of bending since the assembly is selective in direction of bending.

These and other objects and advantages will be readily apparent from the following detailed description of an embodiment of this invention and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of a wiping anvil assembly of this invention mounted on a support and disposed in operative relation to a circuit board having an electrical component assembled therewith.

FIG. 2 is a left side elevational view of the assembly of FIG. 1.

FIG. 3 is a top plan view of the assembly.

FIGS. 4, 5, 6 and 7 are vertical sectional views of a wiping anvil assembly diagrammatically illustrating an operational sequence in bending a component lead.

FIG. 8 is a side elevational view of an apparatus provided with several wiping anvil assemblies of this invention for performing simultaneous bending of several component leads.

FIG. 9 is a vertical sectional view ofa wiping anvil assembly diagrammatically illustrating the mechanical stop limiting pivotal movement of the anvil.

FIG. 10 is a perspective view ofa modified wiping anvil.

DETAILED DESCRIPTION OF THE INVENTION A single wiping anvil assembly embodying this invention is shown in FIGS. 1 and 2 juxtaposed in operative relationship to a printed circuit board B. An electrical component C is assembled with the board with two terminal leads L projecting through respective apertures A formed in the board and extending a distance from the opposite side preparatory to bending into mechanical contacting engagement with associated portions of an electrically conductive circuit P printed on the lower surface of the board. The function of the wiping anvil assembly is to effect the bending operation as diagrammatically shown in FIGS. 4-7 and described in detail hereinafter through a single axis movement of the anvil assembly relative to the circuit board B and assembled component C. In this illustrated embodiment, the anvil assembly is displaced toward the circuit board which is restrained against movement as is the electrical component as by a back up member M.

Having specific reference to FIGS. 1-3, the wiping anvil assembly comprises a driving head 10, collar 11, wiping anvil l2 and biasing spring 13 as the basic components thereof. The driving head 10 includes a bearing block 14 and an upstanding support post 15 carrying the bearing block at the upper end thereof with the support post secured to a support plate 16 in rigidly fixed relationship. F or'purposes of attachment, the support post 15 which is cylindrical has a reduceddiameter end portion. 17 that can project through a mounting hole 18 formed in the support plate. A screwthreaded nut 19 turned onto a similarly threaded portion of the support post 15 bears against a washer 20 disposed adjacent the support plate 16. A shoulder 21 formed at the juncture of the main body portion of the support post and the reduced-diameter portion bears against the support plate at the surface opposite the nut 20 and the nut 19 is able to secure the support post to the plate in a desired angularly oriented position. This assembly permits relative angular adjustment of the support post in conformance with the requirements of a particular operation thereby enhancing the units versatility.

A bearing surface 22 is formed on the axial end of the bearing block 14 opposite the support post 15 and is generally transversely disposed to the longitudinal axis of the support post. Preferably, this surface 22 is flat and angularly disposed relative to the longitudinal axis. Also, in this embodiment, the bearing surface 22 comprises two sections with a relatively smaller portion 22a which may or may not be angularly disposed to the longitudinal axis to avoid an edge-type bearing point. The bearing block 14 is rectangular in cross-section as can be seen in the drawing having parallel, straight sides at right angles to the bearing surface.

Assembled with the driving head is the collar 11 of rectangular cross-sectional shape having a base 25 slideably mounted on the support post for axially reciprocating movement. Formed with the base are a pair of parallel disposed plates 26 extending a distance axially at either side of the bearing block 14. The plates 26 are spaced apart substantially the width of the bearing block 14 which is received therebetween with the straight sides riding along the opposed parallel inner surfaces 27 of the plates thereby preventing relative rotation of the collar and'driving head. Each plate 26 terminates in a flat, bearing-edge surface 28 disposed transversely to the longitudinal axis of the assembly and adapted to engage the printed circuit board in endwise relationship. The outer surfaces of the plates 26 adjacent the terminal ends may be tapered inwardly to reduce the area of the edge surface 28 and the space required between component leads L. The collar base 25 is formed with a axial bore 29 through which the support post 15 extends with the bottom surface of the bearing block 14 engageable with one surface 30 forming a stop. The other end surface 31 of the collar base is transverse to the longitudinal axis of the assembly. and is in opposed relationship to a surface of the support plate 16.

Positioned on the support post 15 is the biasing spring 13 which comprises a helical compression spring. This spring is coaxial to the post and engages with and extends between the collar base surface 31 and the support plate 16 which forms an abutment for the spring. Consequently, the collar 11 is biased to a position where the bottom surface of the bearing block 14 engages the collar base-surface 30, but may be axially displaced toward the support plate 16.

Pivotally mounted on the collar 11 is the wiping anvil 12 which comprises a flat plate 35 of rectangular shape. A pair of cylindrical hinge pins 36 are formed with the plate 35 adjacent an end edge and project in axial alignment from opposite sides of the plate. Each hinge pin 36 is journalled in a respective bearing aperture 37 formed in the adjacent bracket plate 26 of the collar near the terminal end of the plate such that the plate will be angularly disposed relative to the longitudinal axis of the assembly in downwardly inclined relationship to the bearing block 14 when in the normally biased position of FIGS. 1 and 2. In this position, an edge corner 38 of the plate 35 remote to and parallel to the axis of rotation thereof contactingly engages the bearing surface 22.

Cooperative functioning of the several components can be most clearly seen with reference to the sequential operation of the wiping anvil assembly in bending the component lead L in FIGS. 4-7. In this sequence, reciprocating movement of the wiping anvil assembly relative to the assembled component C and circuit board B is assumed with exemplary apparatus for effecting this movement being shown in FIG. 8. This apparatus is of a basic form including a rigid C-shaped frame 40 having a pair of support brackets 41 secure to the upper arm for engagement with and support of a printed circuit board B having several electrical components C assembled therewith. The brackets 41 maintain the board and components against the upper arm of the frame 40 with this arm having the lower surface thereof functioning as the back-up member M to restrict movement. Several wiping anvil assemblies equal in number to the number of component leads L for concurrent bending of all leads are mounted on a single support plate 16 which is carried by the piston rod 42 of a fluid actuating unit 43 attached to the lower arm of the frame 40. Operation of the actuating unit 43 extends the piston rod 42 thereby elevating the support plate 16 and displacing the anvil assemblies into operational engagement with the respective component leads.

Referring to FIGS. 4-7, a single wiping anvil assembly is shown successively displaced starting from the position of FIG. 1 where the component C and circuit board is positioned above the assembly with a terminal lead L substantially coaxially aligned with the longitudinal axis. In FIG. 4, the anvil assembly has been upwardly displaced to bring the anvil plate 35 into engagement with the lead. In this position, an upward force is applied to the lead L but the back-up member M prevents upward displacement of the component C. Further upward displacement as in FIG. 5, initiates bending of the lead in a desired direction as determined by the relative direction of inclination of the plate 35 with the anvil assembly being appropriately oriented when initially mounted on the support plate 16. At this stage of the operation, the collar 11 and driving head 10 are maintained in their normally biased position by the spring 13 which is selected to be capable of exerting a greater biasing force than the opposed force of initially bending the lead.

Continued upward movement of the anvil assembly will result in the biasing force of the spring 13 being overcome and the edge surface 28 of the plates 26 being forced into engagement with the circuit board B or printed circuit P as shown in FIG. 6. Overcoming the biasing force of the spring B, whether as a consequence of the opposing force required to further bend the lead L or the collar 11 engaging the circuit board B and being prevented from further upward movement, re-

sults in relative axial movement of the driving head 10.

and collar and upward swinging movement of the anvil plate 35. During movement of the assembly from the position shown in FIG. 5 to that of FIG. 6 causes the plate edge 38 to slide upwardly of the inclined bearing surface 22 as the driving head 10 moves upwardly between the bracket-forming plates 26 of the collar 11. After the anvil plate 35 has been swung to about the position shown in FIG. 6, the bearing surface 22 will engage the lower surface of the plate with either the oppositely inclined portion 22a or the juncture line of the two surface portions being in contact therewith.

At completion of the bending operation, the anvil assembly will have been upwardly displaced to the position shown in FIG. 7 where the anvil plate 35 is substantially horizontally disposed and that portion of the component lead L projecting below the circuit board B has also been turned through an angle of at least 90 and forced into mechanically contacting engagement with the printed circuit P. The degree of angular displacement of the anvil plate 35 is dependent on relative physical dimensions of the assembly, such as the distance that the hinge pins 36 are located from the edge surface 28 of the plates 26 and the relative thickness of the component leads L. As can be readily seen from the sequential operation views, a relatively smaller diameter lead than that shown will permit further swinging of the plate.

In the embodiment illustrated in FIGS. 1-9, the wiping anvil assembly is of a construction such that the anvil I2 is freely pivotable and it is necessary to assure that the anvil is normally disposed in contacting relationship with the bearing surface 22 of the driving head 10. The primary application of thisapparatus is with the anvil assembly vertically disposed and the anvil I2 uppermost. This orientation would normally maintain the anvil in the desired position; however, to avoid having the anvil inadvertently displaced to an ineffective or inoperative position, a mechanical stop 45 is formed in each of the plates 26 of the collar 11. This mechanical stop 45 in this embodiment comprises a projection directed inwardly of each plate 26 at the top bearing edge 28 and located substantially vertically above the pivot axis of the anvil 12. As can be best seen in FIG. 9, this stop 45 prevents pivoting of the anvil 12 further than illustrated and the anvil will return bygravity to an operative position.

A modified anvil plate 46 is shown in FIG. and may be advantageously utilized in this wiping anvil assembly in place of the previously disclosed flatsurfaced plate 35. This modified plate is formed with a concave groove 47 of V-shape extending longitudinally of the anvil. During the course of operation of the anvil assembly, a component lead would cooperatively engage the grooved surface and be accurately directed during bending thereof in alignment with the longitudinal axis of the plate. This is a particularly desirable feature with respect to round component leads which could otherwise be bent at an angle relative to the longitudinal axis of the anvil plate.

While the preceding description and accompanying drawings are illustrative of an exampleapplication such as printed circuit boards and electrical components assembled therewith, it will be readily seen that this novel apparatus may be utilized with other workpieces also requiring a similar bending operation. For example, this wiping anvil assembly may be utilized to bend leads on electrical components not assembled with a circuit board and that the degree of bend may be other than the illustrative 90. Irrespective of the specific application.'the novel wiping anvil assembly comprising a driving head cooperating with a pivotable anvil in a collar provides a 90 bend with a single rectilinear motion of the apparatus. This results in a simplified and economically manufacturable apparatus.

I claim:

1. A wiping anvil assembly for bending component leads comprising A. a driving head adapted to be supported for rectilinear movement along a longitudinal axis alignable with a component lead, said driving head having a bearing surface disposed generally transversely to the longitudinal axis,

B. a collar assembled with said driving head for relative axial movement parallel to the longitudinal axis,

C. resilient biasing means interengaged with said driving head and said collar urging said collar and driving head to a first relative position and permitting relative axial movement therefrom to a second relative position in opposition to a force exceeding a predetermined value,

D. a wiping anvil pivotally mounted on said collar for swinging movement about an axis transverse to the longitudinal axis and engageable with said drivinghead bearingsurface, said anvil being angularly disposed to the longitudinal axis, and at a side most closely adjacent said driving head of a plane passing through the anvils pivotal axis and perpendicular to the longitudinal axis when said driving head and collar are in said first relative position and pivotable to a lesser angular disposition at the opposite side of said plane passing through said anvils pivotal axis through relative axial displacement of said collar and driving head from said first relative position to said second relative position thereby bending a component lead engaged by said anvil, said anvil having a point thereof remote to its pivotal axis contacting the bearing surface of said driving head throughout displacement of said anvil to at least said lesser angular position.

2. A wiping anvil assembly according to claim 1 wherein said driving head includes an elongated support post extending axially opposite from the bearing surface thereof parallel to the longitudinal axis and said collar is slideably mounted on said support post and includes a bracket projecting a distance axially at the other side of driving head with said wiping anvil pivotally mounted thereon.

3. A wiping anvil assembly according to claim 1 wherein said driving head includes an elongated support post extending axially opposite from the bearing surface thereof parallel to the longitudinal axis and said collar includes a base slideably mounted on said support post and a pair of bracket-forming, spaced parallel plates projecting a distance axially thereof at the other side of said driving head, said wiping anvil pivotally mounted between said plates.

4. A wiping anvil assembly according to claim 3 wherein said biasing means comprises a helical compression spring positioned on said support post between said collar base and an abutment fixedly positioned relative to said support post.

5. A wiping anvil assembly according to claim 1 wherein said wiping anvil comprises a flat plate pivotally mounted on said collar.

6. A wiping anvil assembly according to claim 5 wherein said plate includes an edge spaced parallel to the transverse axis of rotation thereof and engageable with the bearing surface of said driving head.

7. A wiping anvil assembly according to claim 5 wherein said collar and said driving head include means cooperating therebetween preventing relative rotation, said driving head bearing surface having a flat-surfaced portion angularly disposed to the longitudinal axis opface thereof, said collar is slideably mounted on said support post, and said biasing means comprises a helical compression spring positioned on said support post between said collar and an abutment in fixed relationship to said support post.

10. A wiping anvil assembly according to claim 5 wherein said flat plate has a longitudinally extending, concave groove formed in a surface thereof to engage with a component lead.

Claims

1. A wiping anvil assembly for bending component leads comprising A. a driving head adapted to be supported for rectilinear movement along a longitudinal axis alignable with a component lead, said driving head having a bearing surface disposed generally transversely to the longitudinal axis, B. a collar assembled with said driving head for relative axial movement parallel to the longitudinal axis, C. resilient biasing means interengaged with said driving head and said collar urging said collar and driving head to a first relative position and permitting relative axial movement therefrom to a second relative position in opposition to a force exceeding a predetermined value, D. a wiping anvil pivotally mounted on said collar for swinging movement about an axis transverse to the longitudinal axis and engageable with said driving-head bearingsurface, said anvil being angularly disposed to the longitudinal axis, and at a side most closely adjacent said driving head of a plane passing through the anvil''s pivotal axis and perpendicular to the longitudinal axis when said driving head and collar are in said first relative position and pivotable to a lesser angular disposition at the opposite side of said plane passing through said anvil''s pivotal axis through relative axial displacement of said collar and driving head from said first relative position to said second relative position thereby bending a component lead engaged by said anvil, said anvil having a point thereof remote to its pivotal axis contacting tHe bearing surface of said driving head throughout displacement of said anvil to at least said lesser angular position.

7. A wiping anvil assembly according to claim 5 wherein said collar and said driving head include means cooperating therebetween preventing relative rotation, said driving head bearing surface having a flat-surfaced portion angularly disposed to the longitudinal axis oppositely to said anvil with the anvil engaging said flat-surfaced portion.

8. A wiping anvil assembly according to claim 5 wherein said collar includes stop means cooperatively engageable with said anvil to limit pivotal movement thereof, said stop means formed with said collar to prevent pivoting of said anvil beyond a vertical position.

9. A wiping anvil according to claim 1 wherein said driving head includes an elongated support post extending axially opposite thereof from the bearing surface thereof, said collar is slideably mounted on said support post, and said biasing means comprises a helical compression spring positioned on said support post between said collar and an abutment in fixed relationship to said support post.