US3255654A - Punch retaining-spring type keeper - Google Patents

Description

June 14, 1966 R. BLElcHER 3,255,654

PUNCH RETAINING-SPRING TYPE KEEPER Filed May 25, 1964 6 f 34 3 4' (@n@ A! 51 ejector pin.

United States Patent() 3,255,654 PUNCH RIETADIING-SPRMG TYPE KEEPER Robert I.. Bleicher, Dayton, Ohio, assigner to Dayton llerforators, Inc., Dayton, Ohio, a corporation of Ohio Fiied May 25, 1964, Ser. No. 369,968 7 Claims. (Cl. Sii- 128) This invention relates to a novel keeper device.

Embodiments have particular advantage in application to a Iektole type punch and will be so described. However, it will be readily obvious that the application of the invention is not so limited and such is not intended in this instance.

A Jektole is a piercing type punch having a spring biased ejector pin operative to automatically dislodge blanks which tend to adhere to its operating or work engaging face. Due to the inherent nature of its function,

its work engaging face is subject to Wear. This necessitates frequent grinding to square the working face. The present invention facilitates this grinding and enables that it be accomplished without need for removal of the For that matter it facilitates dressing the ejector pin in the course of the same grinding procedure.

A primary object of the invention is to provide a keeper device of a unique character'which is economical to fabricate, more efficient and satisfactory in use, adaptable to a Wide variety of applications and unlikely to malfunction.

Another object of the invention is to provide a keeper device which facilitates the lock of a spring biased element in a retracted position.

A further object of the invention is to provide means facilitating an automatic locking of a spring biased element relative its housing structure.

An additional object of the invention is to provide an improved keeper device for the ejector pin of a Iektole type punch which is equally effective in all similar applications.

Another object of the invention is to provide a novel device facilitating the grinding of a piercing type punch which incorporates an ejector-element.

Another object of the invention is to provide a keeper device possessing the advantageous structural features, the inherent meritorious characteristics and the means and mode of operation herein described.

With the above and other incidental objects in view as will more fully appear-in the specification, .the invention intended to be protected by Letters Patent consists `of the features of construction, the parts and combinations thereof, and the mode of operation as hereinafter described or illustrated in the accompanying drawings, or their equivalents.

Referring to the accompanying drawing wherein are shown some but obviously not necessarily the only form of embodiment of the invention,

FIG. 1 is a view of one form of keeper element in accordance with the invention;

FIG. 2 is an end view of the device of FIG. 1 as applied to a piercing type punch which includes an ejector element;

FIG. 3 is a vertical elevation lof the punch of FIG. 2, shown partly in section, illustrating the effective containment of the ejector element by the keeper device of FIG. 1; i

FIG. 4 shows a plan view of a further form of the device of FIG. 1;

FIG. 5 is a View of the device of FIG. 4 in application to a punch such as shown in FIGS. 2 and 3, the punch in this instance having a smaller diameter; and

FIG. 6 is a side view of the device of FIG. 4.v

Like parts are indicated by similar characters of reference throughout the several views.

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The keeper of FIGS. 1 through 3 of the drawings is formed of a single length of wire 10 having the characteristic of being resilient when properly coiled.

In creating the illustrated embodiment, the wire 10 is coiled on itself to form a circular loop 11 adjacent its approximate center. The coil is so continued as to cause portions of the wire to superpose for approximately and preferably not less than of the circular extent of the loop. The resultant form of the Wire provides that its respective end portions 12 and 13 project in generally the same sense and in relatively adjacent planes.

The wire portion 12 orients tangential to the loop and generally perpendicular to a diameter thereof which is essentially defined by the form of the relatively superposed portions of the wire. The projected extremity of the wire portion 12 is bent to form a right angled hook 14, the terminal portion of which extends in the direction of the wire portion 13 and generally parallel to the aforementioned diameter.

The wire portion 13 is also tangential to the loop 11 but in a sense to have its section 1S immediately adjacent the loop slightly inclined to the wire portion 12. The section 15 terminates at a point 16 preceding and spaced from the hook 14. Beyond the point 16 the wire portion 13 consists of a V-shape section 17r the trough or apex of which projects in a sense away from the wire portion 12 and generally coincides with the projected extremity of the hook 14.

The resultant structure provides a keeper the portions 12 and 13 of which are biased to a predetermined position, as may be observed with reference to FIG. 1 of the drawings, in which the hook 14 and the trough' 17 tend to resist relative displacement in a sense outwardly from each other.

As perviously mentioned, this keeper is most advantageously employed in application to a piercing type punch incorporating a biased ejector .pin in the manner of a Iektole unit. Referring to FIGS. 2 and 3 of the drawings, this punch comprises a tubular body 2t) terminating to one end in a punch portion formed by a reduction of its external diameter. The projected extremity of the punch portion provides a working face 21 which occupies a plane at right angles to the major axis of the body 20. The end of the -body 20 remote from its working face 21 is formed with a radially expanded head portion 22, by means of which the punch may be secured in reference to a holder unit (not shown). I

Being counterbored to its head end, the body 20 is provided with a through passage including a relatively expanded portion 23 the inner limit of which is defined by an annular shoulder 24. The shoulder 24 lies in a plane generally parallell to the punch working face 21 and slightly in advance of the punch portion of the body 20.

Housed in the relatively reduced portion of the through passage of the body 20 is an ejector pin 25. The pin 25 includes a relatively expanded head portion 26 contained in the passage portion 23 by the relatively adjacent shoulder 24. A spring 27 is housed in the passage portion 23 between the pin head 26 and a screw 28 threadedly engaged in the head end of the body 20. T he spring 27 is so contained to'normally induce a bias of the head 26 to the shoulder 24. The bias is suicient to normally cause the pin 25 to project relative the punch working face 21. The purpose of the bias on the pin 25 is to facilitate dislodging cut blanks which tendl to adhere to the work engaging face in the use of the punch element.

As may be observed with reference to FIG. 3 of the drawings, the body 20 includes a radial aperture 29 which opens to the passage portion 23 immediately adjacent the shoulder 24. It is to be understood that when projected 'a e: due to the bias thereon, the pin 25 has its head 26 normally positioned to seal the inner end of the radial passage 29 and thereby prevent access to the passage portion 23.

In use the working face of a piercing -punch as above described takes a considerable beating. This means that it is frequently necessary to square the working face by a grinding procedure. The use of a keeper device in accordance with the present invention facilitates this procedure.

It may be seen that the relatively projected hook and trough-like extremities of the wire portions 12 and 13 form a generally modified rectangular loop. This loop is slid over the piercing end of the punch to frictionally engage about the relatively expanded portion of the body 20, in the transverse plane thereof occupied by the radial aperture 29. On pulling laterally on the wire element 19 through the medium of the coil 11 and inducing a spreading of the wire portions 12 and 13, one may cause the portion of the body 2t) diametrically opposite the opening to the aperture 29 to nest in the trough section 17 of the wire portion 13 and the hook 14 to enter the aperture 29. Since the wire portions 12 and 13 tend to bias towards each other to assume their normal position as previously described, there is a significant bias on the hook 14 in the direction of the trough section 17. This bias is sufiicient that upon one pressing the normally projected ejector pin 25 inwardly of the working face 21 of the body 20 and the pin head 26 is displaced thereby from the path of the hook 14, the hook 14 will automatically be induced to move inwardly of the passage portion 23 in the path of the head 26. This prevents the head 26 from being biased to the shoulder 24- and thereby positions the ejector pin inwardly of the punch body. In this simple fashion the punch unit may be conditioned so that, as shown in FIG. 3 of the drawings, the operating face 21 may be squared by a grinding wheel in a quick and efficient manner. The ejector pin 25 may obviously have its tip squared in the same grinding procedure.

The facility afforded by the use of the keeper element in accordance with the invention in respect to the described application is believed readily obvious. One need only orient the keeper element and it will automatically assume its locking position in respect to the head of the pin 25 as the ejector pin is pressed inwardly of the punch body.

While the keeper of the invention is described in a limited application, it should nevertheless be obvious it can be just as easily and advantageously applied to other and similar applications where a biased element is required to be positioned in a locked 0r retracted condition for anypurpose.

Another form of embodiment of the invention for similar purposes is revealed in FIGS. 4 through 6 of the drawings. This embodiment is particularly applicable to piercing type punches and the like of relatively small cross-sectional dimension.

This embodiment of the invention is formed, similarly to `that the first described, of a single length of wire 30. The wire 30 is coiled on itself to form a circular loop 31 adjacent its approximate center.' The coil is so continued as to cause portions of the wire to superpose for slightly more than 180 of the circular extent of the loop. One end portion 32, noting FIG. 4 of the drawings, extends tangential to the loop 31 and at right angles to a diameter formed by the superposed portions of the wire Since the extent of the superposing of the wires is greater than 180 the other end portion 33 of the wire 3i) exists tangential to the loop 31 but sharply inclined to the wire portion 32;k This inclination is terminated at a point 36 short of the projected extremity of the wire portion 32 which is defined by a right angled hook section 34. The hook 34 is directed towards the wire portion 33. Beyond the point 36 the wire portion 33 first extends generally parallel to the wire portion 32 in the sense of its exit line tangential to the loop 31 until it crosses the projected extremity of the hook 34, in a plane immediately adjacent thereto. Beyond the hook 34 the wire portion 33 terminates in a section 37 which is further inclined to the wire portion 32.

In using this last form of embodiment of the invention in reference to a piercing type punch of similar nature but smaller diameter than that shown in FlG. 3 of the drawings, the piercing end of the punch is initially received between the wire portions 32 and 33 as the keeper is slid over the punch. The keeper is positioned in the transverse plane common to a lateral aperture 29' in a punch body 46 as previously described and the keeper drawn laterally of the punch body through the medium of its circular loop 31. As this occurs, the wire portions 32 and 33 are relatively spread and the portion of the punch body diamctrically opposite the entrance to aperture 29 is caused to nest in the trough created by the sections 37 to the end of the wire portion 33. As this occurs the hook 34 is induced to enter the aperture 29 and, as previously described, abuts the contained head of the ejector pin which is housed in the punch body. Here also, one need only press the ejector pin inwardly of the body @il so as to clear its head from the path of the hook 34 whereupon the form of the coiled wire causes the hook 34 to bias inwardly of the body in the path of the head of the pin. This establishes the pin in a locked or retracted position and permits the grinding procedure as previously described.

From the preceding it should be readily apparent that the invention device may be simply and economically fabricated and applied in a wide variety of applications in a manner believed obvious.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is suseeptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprise but one of several modes of putting the invention into effect, and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the applied claims.

Having thus described my invention, l claim:

1. A keeper device comprising a single length of wire coiled on itself at its approximate center to have its ends project therefrom in the same sense, said ends exiting tangential to the coil, one initially inclined toward and biased to the other and then diverted to terminate in an angularly formed extremity, the other end having a bent extremity normallj,l biased to form a loop with said angular extremity, which loop is projected relative said coil.

2. A keeper device comprising a single length of wire coiled on itself to have its ends project therefrom in generally the same sense, said ends exiting tangential to the coil, one initially inclined toward the other and then diverted to a V-form, the other end terminating in a right angled form, the extremity of which is biased to normally project in a sense inwardly of said V-forrn portion of said one end of the wire.

3. A keeper device comprising a single length of wire coiled on itself to have its ends project in generally the same sense, said ends being arranged to exit tangential to the coiled portion of said wire, one end being initially inclined toward and biased to the other and then diverted to have a portion extend generally parallel to a portion retracted position comprising, a spring-like wire element coiled on itself at its approximate center with opposing arms projecting thereform in a generally side-by-side spaced relation, said arms being biased to resist relative spreading movement, the end of one of said arms being formed as a hook bent toward the end of the other arm, a portion of at least one of said arms inclining 4toward the other in the direction of the ends of said arms to define between said arms adjacent to said center a location of relatively wide spacing adapted to receive a punch body therein, the spacing between said arms narrowing throughout the length of said inclined portion, a lateral pulling motion exerted on said device causing said inclined portion to react on the punch body to spread the ends of said arms, said hook seeking access to the interior of lthe punch body to hold the ejector pin in a retracted position. Y

5. A keeper device according to claim 4, characterized in that the coiled center of said Wire element is fonned as a loop adapted for the grasp by the fingers to facilitate lateral pulling motion of said device as described.

6. A keeper device according to claim 4, characterized in that the said end of the said other arm of said Wirelike element is formed to provide a seat for the punch body, the lateral described pulling motion of the device being continued until said punch body engages in said seat.

7. A keeper device according to claim 4, characterized in that said inclined portion is formed on said other arm, said inclined portion terminating in a seat portion at the end of said other arm disposed opposite said hook and adapted to engage said punch body when brought to cooperative relation therewith by lateral pulling of said device as described.

References Cited bythe Examiner UNITED STATES PATENTS 993,773 5/1911 Grabau 24-261 X 2,674,071 4/ 1954 Rhees 23S-8.8 2,917,960 12/1959 Gargrave 83-128 2,926,033 2/1960 Zarrillo 85-8.8 X 2,985,932 5/1961 Windish 24-261 X WILLIAM W. DYER, JR., Primary Examiner.

L. B. TAYLOR, Assistant Examiner.

Claims (1)

1. A KEEPER DEVICE COMPRISING A SINGLE LENGTH OF WIRE COILED ON ITSELF AT ITS APPROXIMATE CENTER TO HAVE ITS ENDS PROJECT THEREFROM IN THE SAME SENSE, SAID ENDS EXITING TANGENTIAL TO THE COIL, ONE INITIALLY INCLINED TOWARD AND BIASED TO THE OTHER AND THEN DIVERTED TO TERMINATE IN AN ANGULARLY FORMED EXTREMITY, THE OTHER END HAVING A BENT EXTREMITY NORMALLY BIASED TO FORM A LOOP WITH SAID ANGULAR EXTREMITY, WHICH LOOP IS PROJECTED RELATIVE SAID COIL.

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