US3329001A

US3329001A - Hand tool for adjusting needle eye laps

Info

Publication number: US3329001A
Application number: US382331A
Authority: US
Inventors: Arthur J Ringzelli; Edwin H Rombin
Original assignee: ACRO DIE AND STAMPING CO
Current assignee: ACRO DIE AND STAMPING CO
Priority date: 1964-07-13
Filing date: 1964-07-13
Publication date: 1967-07-04
Anticipated expiration: 1984-07-04

Description

July 4, 1967 RINGZELL. ETAL 3,329,001

) HAND TOOL FOR ADJUSTING NEEDLE EYE LAPS Filed July 13, 1964 INVENTORS.

ARTHUR J. RINGZELLI ROMBIN EDWIN AIT 7 United States Patent 3,329,001 HAND TOOL FOR ADJUSTING NEEDLE EYE LAPS Arthur J. Ringzelli and Edwin H. Rombin, Chicago, IlL, assignors to Acro Die and Stamping (30., Chicago, 111., a corporation of Illinois Filed July 13, 1964, Ser. No. 382,331 Claims. (Cl. 72-409) The present invention relates to a tool for adjusting the working size of an improved needle eye lap and more particularly to a simple pincer type tool combination that can be used to expand or correct a wide range of lap sizes as they were or are used for different size holes.

Lapping is a surface finishing process commonly used whenever a drilled or reamed hole has to be further processed for close tolerances and satin finishes. Holes are lapped by reciprocating and progressively rotating rodlike tools or laps that fit snugly in the hole and are supplied with an abrasive compound between the engaging surfaces of the lap and the hole. Laps are generally made from a relatively soft metal so that the abrasive becomes somewhat imbedded in the lap instead of the workpiece in order to size and finish the wall of the hole. During the process the lap becomes worn as the hole is slightly increased in size thereby making it necessary repeatedly to increase the size of the lap so as to again contact the walls of the hole with a lapping pressure contact.

A superior lapping tool is found in the needle eye lap characterized by split and spread semicylindrical sections extending over a predetermined length of solid rod stock. This arrangement has the advantages of a dual resilient action to force the external working faces of the sections against the walls of the hole and with its reciprocation and progressive rotation not only is an excellent finish provided but the objectionable bell mouth shape is eliminated that occurs in other lapping processes such as with tapered laps. Since this method is inherently superior to other laps it has long been sought to develop a tool whereby the needle eye sections could be easily adjusted by the use of a simple hand tool that will fit all sizes and lengths of needle eye laps to spread or close the two sections accurately in a strictly diametrical direction with respect to each other. Moreover some difficulty has been experienced in maintaining a goodly supply of grinding compound at the working interfaces because the peripheral edges of the sections wear sharp and tend to scrape clean or block inflow of compound to the interface working areas when progressively turned.

An improved tool for this purpose and also an improved needle lap is provided which not only lend themselves to a novel cooperating relationship with improved results but also provide greatly improved results in the lapping performance of the lap.

It is an object of this invention to provide a tool of the above requirements that will retain these characteristics with a minimum of care and will not become damaged or inoperative during normal usage.

A further object is to provide in one tool two identical but symmetrically opposed elements that can be used in any one of a number of orientations in the needle eyes of laps of all sizes, including the smallest, and when pincered with respect to each other the elements resiliently provide a wide range of spreading distances with a uniformity that is normal to the axis of the lap for each lap regardless of its size.

A further object is to provide a needle eye lap in which ice the edges of the semicylindrical sections are rounded to assist engagement and cooperation of the tool with a surface being lapped and further improves the feed of grinding compound into the working area of the engaging surfaces as the lap is rotated progressively during its reciprocation.

Another object of the invention is to provide a tool that can be used to expand the needle eye lap sections different distances if desired at different locations along the eye, so that the lap can be adjusted as to its outside dimension at any station on its lapping surface. For example, portions of needle eye sections can be spread more at the heel end of the lap than at the toe end for easy entry of the lap into the hole. Then as the heel becomes worn and the lapping progresses the toe end can be increased to provide a new unworn lapping surface of the lap to contact the wall of the hole.

More particularly as distinguished from previous methods of spreading needle eye laps by cold chisels, wedge and anvil elements driven by a hammer or jaws of a vice that bends and distorts the lap, the present invention is characterized by two symmetrically matching, sharp, wedgelike edges on pincer-like jaws that are pointed towards each other for insertion into lap eyes without the sharp edges contacting any surface or body that would dull them, and, if overdriven by excessive force will sideslip into an overlapping relationship that quickly obstructs further movement even to the point of intentional destruction.

The invention is further characterized by the provision of blunted contacting portions on the mating working edges of the tool that prevent the sharp portions thereof from contacting one another and dulling. This further provides a portion which can also be used in a pincer fashion to squeeze the eye lap sides towards each other to reduce the outside diameter of the lap if desired.

Other objects and advantages will appear when referring to the description and in the following drawing in which:

FIG. 1 is an elevational assembly view of the two identical members of the tool as embodied in a hand type of pliers;

FIG. 2 is a sectional view of the closed position of the jaws at 22 of FIG. 1;

FIG. 3 is an enlarged cross-sectional view of the contacting jaws of FIG. 2;

FIG. 4 is an enlarged fragmentary perspective view of the jaws separated and engaging a needle eye lap in phantom;

FIG. 5 is a top view of the working portion of an improved needle eye lap; and

FIG. 6 is a cross-sectional view of the needle eye lap at 6-6 of FIG. 5 with the open spreading tool shown in phantom engaging the needle eye of the lapping tool for spreading.

Referring to FIG. 1, the assembled tool is shown and comprises two identical heavy sheet metal stampings 2 approximately .125" thick comprising elongated members 4 which are pivotally connected at 6 by any desired means such as a hollow rivet pin 8. Each member 4 comprises a curved handle portion 10 at one end, increasing in Width toward the point of pivotal connection 6 and a narrow neck 14 having a jaw 12 thereon extending beyond the point of pivotal attachment 6 in the opposite direction of the handle 10. The jaws terminate in wedge-shaped projections 16 and when assembled their apex edges 18 point in the direction of closing. The side faces 26 of 3 the wedge elements 17 are the working faces and the narrow necks 14 in combination with the tight rivet provide some resilient yield for the edges 18 to side-slip with respect to each other in a direction radial to the pivotal connection when violently overdriven towards each other. The included angle of the wedge 16 can range between 50 and 70 but preferably is 60. Such is best suited for the tool and purpose intended. It provides an optimum angle for a wide spreading range for lap eyes without full closure of the jaw; confines any overlapping of the jaws edges to a very limited degree if excessively forced towards each other thereby eliminating any need for closure stops; and, provides a desired shape easily and economically produced in a stamping operation without tearing the metal.

The relationship between the wedges 16 of the jaws 12 when the jaws 12 are closed is shown in FIGS. 2 and 3. It is seen that the apex edges 18 are not parallel throughout their length but have a slight taper or relief 20 extending from a sharp end portion 21 towards the other end 24 whereby the jaws 12 contact only at the mid-portion 22 of the edges 13 when closed. This slight taper is accomplished in the shearing process and remains after shaving the working faces 26 to make them smooth. It is not necessary to grind the edge 18 to this shape although such can be touched up on a grinding wheel if desired.

FIG. 4 shows an engaging relationship of the wedges 16 of the jaws 12 with a needle eye lap 28 when spreading a portion of the lap eye 29 thereof. It is noted in this view that where the edges 18 are tapered in relief, the unpointed blunt surfaces 24 are formed in the stamping operation by the termination of the sharp ends 21 of the edges 18 at or above the theoretical apex of the included angle 6. The sharp ends 21 of edges 18 project the furthest and are utilized to direct the tool to enter the smallest lap eye and begin expanding the lap eye by the force of the divergence of the working faces 26 of the wedges 16 against the inner surfaces of the lap eye. If the eye is expanded so far that the jaws 12 close, the blunt portion 24 of one wedge 16 will come in contact with the corresponding blunt portion 24 of the opposite wedge 16 at the midportion 22 leaving the sharp leading edges 18 free of any contact, thereby retaining the sharp edges 18 for continued easy insertion into needle eye laps. Preferably the working faces 26 otherwise define rectangular surfaces parallel to the axis of the lap when in working engagement with the

lap eye portions

32 and 34 which will be further described later.

Referring to FIG. 3, in conjunction with FIG. 4, it was seen that the midportions 22 of the blunt surfaces 24 are the elements which contact and stop the tool from further closing in normal use to prevent damage to the sharp end portions. The midportions 22 of the blunt surfaces 24 are also used in the manner of a simple pliers to pinch the needle eye lap portions together if the lapping portions have been overspread. This is done by placing the portions of the needle eye lap between the blunt midportions 22 of the Wedges 16 and applying a gripping force to the handles 10. Thus the lap eye can be expanded and reduced as desired very quickly and easily with minimal effort right at the site of the lapping operations. A sufiicient force to reduce the size of the diameter of the lapping portion of the needle eye lap can be applied without causing the blunt portions 22 of the wedges 16 to damage the lapping surfaces. Furthermore, as the blunt midportions 22 of the wedges 16 are the only portions that make any contact, the sharp edges 18 are not made dull but remain free of contact and retain their sharpness for continued usage.

It will also be observed that the tool is manipulated mainly at right angles to the lap thereby being usable with needle eye laps of any length and size.

The working portion of the improved needle eye lap- 28 is shown in FIGS. and 6. Needle eye laps are formed by splitting rod stock 30 diametrically from opposite sides at 38 and 40 along a portion of its length to divide it into two identical

semicylindrical portions

32 and 34. The cutting dies performing the cut distort the stock from true semicylindrical shapes and provides spaces 41 between them that taper towards the axis of the rod and in which lapping compound can be placed. The splits at 38 and 40 also provide throats for guiding the entry of the spreading wedges 16 of the spreading tool, shown in dotted lines, into the cut 36 as shown in FIG. 6.

In this connection it will be observed that the edges of the

notches

38 and 40 have been rounded as at 42 to further widen the effective mouth of the

notches

38 and 40 for easier entry of the spreading wedges 16 of the tool 2 into the

notches

38 and 40 and these rounded edges 42 provide tapering entrance portals between the wall of the hole and the

tool portions

32 and 34 through which the lapping compound carried in the spaces 41 is fed between the wall of the hole and the working surfaces of the lap as the lap is turned slight increments of movement during its reciprocation thus improving the resulting lap and reducing the time required to complete each lapping operation. Rapid reciprocation and progressive turning of the needle eye lap near the terminals of the reciprocation operate to surge lapping compound in between the working surfaces.

From the foregoing description it will be seen that a simple pincers-type hand tool that is used in conjunction with an improved needle eye lap whose rounded notches aid the flow of lapping to and from the working areas as the lap is actuated with a unique relationship between the contacting jaws that enable the tool to always retain a sharp leading edge on the wedge shaped jaws by having the contact when the jaws are closed on a blunt relieved portion of the wedge with the further included means of using the blunt midportion of the wedge of the jaws as a flat surface that will not cut the lapping surface of the needle eye lap when placed in that portion for reducing its lapping diameter if overspread. The main advantage of this tool is its capability to be used either as a spreader or pincer while retaining a sharp edge so that one simple universally usable tool can be used in adjusting all sizes of laps.

What is claimed is:

1. A tool comprising a pair of movable members supported for relative movement towards one another and having closable wedge shaped jaws with working edges directed towards each other in the direction of closing, the edge of each jaw being sharp adjacent one end portion and blunt over the remaining portion with the edges arranged asymmetrical about their midpoints so that when the jaws are in the closed position the sections of the blunt portions contact each other and the sharp end portions of each edge are free of any contact with the other edge.

2. A tool comprising a pair of identical movable members pivotally attached to permit movement towards one another and having closable wedge shaped jaws pointed in the direction of closing, the edge of said jaws having a leading sharp portion adjacent one end with a tapered relief on the other side forming a blunt area, said blunt areas being the contacting surface between the edges when said jaws are in the closed position leaving said sharp edge free from contact with any surface.

3. A tool for use in conjunction with adjusting needle eye laps comprising a pair of identical movable members mounted for relative pivotal movement, each of said members having a handle portion and jaw portion, the jaw portions being terminally wedge shaped and their edges pointed towards each other in the direction of closing, said edges each having a tapered relief over a portion of their length and a sharp edge over the remaining length thereof, said reliefs being in contact with each other leaving the sharp edges free from contact.

4. A pincers type tool comprising a pair of identical movable members each having wedge shaped jaws defin;

ing working edges and being pivotally attached for movement of the working edge towards each other upon closure of the jaws, each edge having leading sharp portions disposed asymmetrically with respect to each other when in closed position free of contact with each other, said edges being disposed parallel to the axis of said pivotal movement.

5. A tool for adjusting needle eye laps comprising two pivotally mounted handles with jaws, each of said jaws having terminally sharp tapered memberspointed in the direction of closing having a taper angle of approximately 60, and neck means interconnecting said jaws and handles enabling minimal overlap of said tapered members under excessive strain.

References Cited UNITED STATES PATENTS 1,840,044 1/1932 Mattes 81-425 CHARLES W. LANHAM, Primary Examiner.

Claims

1. A TOOL COMPRISING A PAIR OF MOVABLE MEMBERS SUPPORTED FOR RELATIVE MOVEMENT TOWARDS ONE ANOTHER AND HAVING CLOSABLE WEDGE SHAPED JAWS WITH WORKING EDGES DIRECTED TOWARDS EACH OTHER IN THE DIRECTION OF CLOSING, THE EDGE OF EACH JAW BEING SHARP ADJACENT ONE END PORTION AND BLUNT OVER THE REMAINING PORTION WITH THE EDGES ARRANGED ASYMMETRICAL ABOUT THEIR MIDPOINTS SO THAT WHEN THE JAWS ARE IN THE CLOSED POSITION THE SECTION OF THE BLUNT PORTIONS CONTACT EACH OTHER AND THE SHARP END PORTIONS OF EACH EDGE ARE FREE OF ANY CONTACT WITH THE OTHER EDGE.