US3289523A - Push-on retainers - Google Patents

Description

Dec. 6, 1966 H. KRAMER PUSHON RETAINERS Filed Nov. 24, 1964 INVENTOR /YM/-WV/(f/PHME?,

ATTORNEY United States Patent O M 3,289,523 PUSH-0N RETAHJERS Hyman Kramer, 2764 IE. 16th St., Brooklyn, NX. Filed Nov. 24, 1964, Ser. No. 413,509 4 Claims. (Cl. SS-SS) The present application for Letters Patent is, particularly in its article aspect, a continuation-in-part of application Serial No. 327,672, filed December 3, 1963, now Patent No. 3,215,025.

This invention relates to improvements in push-on retainers and is more particularly directed to an end cap-type retaining device which is adapted to secure itself in endcapping relation to a shaft, spindle or like carrier member when simply pushed over the end thereof.

Continuing experience with end-cap type retainers presently available on the market as wellas with the various improved forms thereof according to my aforesaid application, has demonstrated a feature of objection common to all, namely, that of the difficulty in initially centering them and thereafter engaging them with their carrier members due to the interference to centering and motion of retainer on carrier end stemming from the location of the locking prongs with which said retainers are provided and on whose action depends the holding power of the retainers with respect to their carrier members. In explanation, in the prior forms and makes of push-on retainers, it was conventional to locate the locking prongs thereof so that their inner free ends which project into the interior of the retainer crown portion are disposed closely adjacent the juncture of said crown portion with the brim or washer-like flange portion thereof. In this location, the inner ends of the locking prongs exert a degree of resistance to initial centering of the retainer on carrier-member end which can be substantial if the internal diameter of the retainer crown portion closely approximates the external diameter of the carrier member, which again is necessary for proper locking action of the prongs. And if the retainers are not properly centered initially, either an undue amount of force is required to finally set them or they are likely to assume a cocked position on their carrier members when finally pushed to their final position, which latter is highly objectionable.

A main object of the present invention, therefore, is the provision of a push-on end cap-type of retainer constructed and arranged as to overcome the above-noted objectionable feature of the prior retainer of similar type.

A more particular object of the invention is the provision of a push-on end cap-type of retainer whose locking prongs are effectively located nearer the closed end of the crown portion thereof than are the locking prongs of the prior retainers of similar type, which results in appreciable unobstructed axial space being provided at the end of the crown portion adjacent the brim or washerlike flange portion of the device, as in turn facilitates initial centering of the retainer on a shaft, spindle or like carrier-member end.

The above and other objects and advantages of the present invention will appear from the following more detailed description thereof, in which reference is had to the accompanying illustrative drawings, wherein:

FIG. l is a plan view of a push-on end cap-type retainer according to the invention, looking into the open end of the crown portion and thus onto the under or working facel of the brim or retaining flange portion thereof;

FIGS. 2 and 3 are sections taken on lines 2--2 and 3 3, respectively, of FIG. l;

FIG. 4 is a greatly enlarged `fragmentary perspective View, looking into one of the crown embossments and onto the inside face of one of the locking prongs of a 31,2%,5235 Patented Dec, 6, H966 ICC push-on end cap-type retainer of the invention, this View being intended to illustrate the substantial setting-back of the locking prongs within the crown portion thereof which characterizes the retainer of the invention;

FIG. 5 is a plan View which illustrates the progressive formation of push-on end cap-type retainers of the invention from a strip of suitable retainer material such as sheet steel; and

FIG, 6 is a section taken along line 6-6 of FIG. 5.

Referring to FIGS. 1 4, such illustrate that a push-on end cap-type retainer of the invention basically comprises a cap or crown portion It), an integral brim or retainingflange portion l2 (said portions to be hereinafter for convenience referred to as the crown and the retaining flange, respectively) and circumferentially spaced (usually diametrically opposed) integral locking prongs 14a, 14h whose free ends extend radially and along arcs of a circle of lesser diameter than that of the crown interior into the interior space of said crown lil by an amount and at an inclination such as to permit the retainer to be readily pushed onto the end of a shaft, spindle or like carrier member having diameter slightly less than that of the internal diameter of the crown li), and thereafter to enable the retainer to self-lock itself to said carrier member by virtue of the ability of the arcuate free-end edges of the locking prongs to bite into the material making up the peripheral surface of said member, under a thrust force or forces directed against the under face of the retaining flange and acting in a direction as tends to separate the retainer as a whole from said carrier member.

According to the present invention, the integral locking prongs 14a, Mb, rather than being struck out from the material of the crown and/ or brim at locations thereof such that they flex about root lines disposed either within the area -of the retaining flange or Which substantially coincide with the line of juncture between the crown and retaining flange, as is conventional in the prior pushon end cap-type retainers, are instead not only struck out from portions of the crown wall which are .spaced a substantial distance axially inwardly or toward the closed end lila of the crown so that the prongs flex about root lines which are set `back into the crown, but also are struck `out from the material of radially outwardly projecting -bulges or embossments purposefully formed in the crown wall at diametrically opposed locations thereof, thus to space :said root lines outwardly of the circle of the crown. It will be understood that the expression root lines as herein used means the imaginary lines which extend across the roots of the prongs at the junctures of said prongs and the part, i.e. crown, retaining flange and/or embossments to be described, from which said prongs extend and about which said prongs flex.

More particularly, it is a feature of the invention that outwardly projecting embossments designated l-S and Ztl in the various views are formed in the crown wall and retaining flange at preferably diametrically opposite areas thereof by drawing same fro-m the metal of the crown wall and retaining flange beginning substantially inwardly -of the plane of the retaining flange l2 and extending radially Aoutwardly into said flange. As best seen in FIG. 4, said embossments 18 and 2li are each defined by circumferentially `spaced-apart side walls a, b, a connecting outer wall c and an end wall d which merges into the crown wall at a location which is spa-ced a substantial distance inwardly of the crown from the line of juncture of said crown and said retaining flange. Thus, the embossments 18, 20 each has general U-section in both transverse and vertical planes extending through same and, as will be evident from a consideration of FIG. 4 in particular, the embossments open both into the crown interior and downwardly through the retaining flange 12.

Upon formation of the embossments I8, 2d as aforesaid,

#.9 it becomes a relatively simple matter to form the locking prongs Mn, llrtb `by in effect cutting the end walls d of the embossments `away from both crown walls with which they merg-e and from the embossment side walls a, b to which said end walls lwere earlier integrally joined, along generally U-shaped lines of cut designated Mc in FIG. 2. Preferably, the transverse lines of cut separating the embossment end walls d from the crown wall, rather than being disposed precisely at the juncture of said end walls d and the crown wall, are disposed a small distance away from said juncture in the direction of the crown end wall a, thus to give some added length to the locking prongs being so form-ed, and the Vside lines of :cut extend back into the embossment side walls for a depth such as to provide a workable prong. Such cuttingaaway operation frees the inner end portions of the embossment end walls d yboth from the crnbossrnent side walls a and b and from the crown wall, `so that such end portions now tend to assume the configuration of conventional prongs. Finally, the so cut-free prongs are given the requisite inclination as enables them to act as locking prongs, that is to say, they are coned inwardly into the crown interior space at an angle which does not exceed the so-called friction angle. By the term friction angle as here employed is meant the angle which enables the locking prongs 14a, 14h to flex radially outwardly more or less freely when the retainer is being pushed onto the end of its carrier member in its assembly thereon, but to straighten and thereby the free-end edges thereof to bite into and grip to the material making up the peripheral surface of the carrier member when a thrust force is applied to the retaining flange 12 in direction as tends to cause the retainer as a whole to move axially away from and separate itself from said carrier member.

Push-on end cap-type retaining devices according to the present invention are thus characterized by locking prongs which project into the interior space of the crown or cap portion at locations along the axial dimension thereof which are spaced a substantial distance from the plane of the retaining fiange portion of such devices. Hence, end cap-type retaining devices as herein constructed and arranged can be more readily initially centered on an moved over the ends of their shafts, spindles and the like than was possible with the prior retaining devices of similar type whose locking prongs projected into the circle defining the interior space of the crown portion thereof at locations closely adjacent the juncture of the crown and retaining flange portions thereof, with the result that said locking prongs interfered with both the quick and easy initial centering and the final placement of the retainer on its shaft or other carrier member.

Push-on end cap retaining devices according to the invention lend themselves to cheap, speedy manufacture from a strip ST of sheet steel of the proper gauge in a progressive compound blanking, drawing and piercing die. While such a die is not shown, its progressive action in blanking out each starting disc-form blank SD from which an end cap as herein proposed is ultimately fashioned, in progressively deep-drawing the crown portion 1f) in a plurality of stages (in practice four successive draws) from said blank, in further drawing the diametrically opposed, radially-outwardly projecting embossments 1S, Ztl from side wall areas of the crown portion and adjacent areas of the blank, in piercing said embossments and crown wall in manner as to cut the locking prongs 14a, 1411 therefrom as the strip is moved progressively through the die, and finally in cutting away the finished cap-type fastener from its blank, will, it is believed, be readily apparent to persons skilled in the art from a consideration of FIGS. 5 and 6. As also diagrammatically shown in said views, it will be understood that the end-cap blanks from the starting disc blankingout stage thereof through the prong-piercing or cutting out stage are connected to the strip ST at diametrically opposed portions thereof by connecting webs W, W1, and

that the final end caps are struck out from said blanks along circular lines of severance lying within the outer partcircular lines of cut which define said blanks. It will also be observed that the embossrnents 18, 2d are formed on the same diameter as that of the webs W, W1 which connect the blanks SD to the strip, a feature designed to insure adequate metal into which the embossment bottom portions may extend. Preferably, the bending of the locking prongs 14a, llib to their proper coning angle is also effected in the die, so that the end caps struck from the blanks may be removed from the die as completed articles separately from the scrap discharging therefrom.

While the cap-type retainer of the invention has been described and illustrated as having a closed crown top or inner end litlzz, it may also be fashioned without said top or with an apertured top, thus to be movable to any desired axial position along the length of a shaft, spindle or like carrier member required for a particular fastener application. lt is also within the scope and purview of the present invention to arrange the locking prongs 14a, ift-b so that they lie on a helix corresponding to the pitch of the threads of a bolt, in which case a retainer according to the invention is capable of serving as a push-on securing nut for said bolt.

Without further analysis, it will be appreciated that push-on end cap-type retainers according to the invention satisfies the objectives of the invention in effective and thoroughly dependable manner. However, as many changes coul-d be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

i. An end cap-type retainer device for push-on assembly on the end of a shaft and like carrier member comprising: a cap-form body having a substantially cylindrical crown portion defining a shaft-receiving opening and an integral brim-like retaining flange extending radially outwardly from an end thereof and adapted to take thrust loads applied in axial direction against its under face, a plurality of circumferentially spaced, radially outwardly projecting embossrnents formed in the side wall of said crown portion and terminating at their ends remote from said fiange in substantially plane end walls, and locking prongs comprising areas struck out from at least said end walls and having length such that their free ends extend radially inwardly into the interior space of said crown portion, and said locking prongs further having inclination such that said prongs will fiex outwardly during push-on assembly of the device on said carrier member but will tend to assume radial positions in which the freeend edges thereof bite into the material of the peripheral surface of said member when thrust loads are applied to the under face of said retaining flange as aforesaid.

2. An end cap-type retainer device according to claim l, wherein said embossrnents are formed in the wall of the crown portion adjacent the line of juncture thereof with the retaining flange and extend axially therefrom into said crown portion and their said plane end walls connect to the crown wall at locations which are spaced an appreciable axially away from said line of juncture.

3. An end cap-type retainer device according to claim l, wherein said locking prongs each comprises an area struck out from an embossment end wall and a contiguous area of the crown portion Wall which extends from said embossment in the direction of the top of said crown portion.

Li. An end cap-type retainer device according to claim 2, wherein said embossrnents are hollow and are so formed that they open at their other end through the retaining flange and inwardly to the interior space of the crown portion.

(References on following page) 5 6 References Cited by the Examiner 2,880,641 4/ 1959 Sislik 85-35 UNITED STATES PATENTS 3,153,972 10/1964 Holton 85-35 944,643 12/1909 White 85-36 THOMAS F. CALLAGHAN, Primary Examiner. 2,135,418 11/1938 Timmerman 72-335 2,309,942

2/1943 Ekstedt et al. '72* 33 5 5 M. PARSONS, JR., Assistant Examiner.

Claims (1)

1. AN END CAP-TYPE RETAINER DEVICE FOR PUSH-ON ASSEMBLY ONE THE END OF A SHAFT AND LIKE CARRIER MEMBER COMRISING: A CAP-FORM BODY HAVING A SUBSTANTIALLY CYLINDRICAL CROWN PORTION DEFINING A SHAFT-RECEIVING OPENING AND AN INTEGRAL BRIM-LIKE RETAINING FLANGE EXTENDING RADIALLY OUTWARDLY FROM AN END THEREOF AND ADAPTED TO TAKE THRUST LOADS APPLIED IN AXIAL DIRECTION AGAINST ITS UNDER FACE, A PLURALITY OF CIRCUMFENENTIALLY SPACED, RADIALLY OUTWARDLY PROJECITNG EMBOSSMENTS FROMED IN THE SIDE WALL OF SAID CROWN PORTION AND TERMINATING AT THEIR ENDS REMOTE FROM SAID FLANGE IN SUBSTANTIALLY PLANE END WALLS, AND LOCKING PRONGS COMPRISING AREAS STRUCK OUT FROM AT

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