Method of riveting a headed fastener
The method of the present invention is intended to be used in association with a headed fastener such as a tee nut, but not limited to a tee nut. The present method contemplates embodiments of a riveting pin having protuberances that cause the flared end of the shaft to be flared in one or more discontinuous portions of the circumference of the shaft, whereby “push out” and “spin-out” are deterred. Where the length of the fastener shaft is no longer than the thickness of the material through which it is inserted, a first design of flaring pin is provided. Where the length of the shaft of the fastener employed is greater than the thickness of the material through which it extends, a second embodiment of flaring pin is employed. In the former case, at least one discrete portion of the circumference of the shaft is flared into the wall of the passageway through which the shaft extends. In the latter case, at least one portion of the circumference of the shaft enters the wall of the passageway and at least one other portion folds over the exterior surface of the material.
Latest Patents:
The present invention relates to a method of riveting a headed fastener. In the prior art, it is known to provide a tee nut with a counterbore that makes it easier to rivet the tee nut either over a surface of a material or within a hole formed therethrough. Counterbored tee nuts have been known since as long ago as the late 1980s. A counterbored tee nut with a circular flange has been marketed since at least as early as 1988. In 1992, a counterbored tee nut having an octagonal flange was developed by Sigma Tool & Machine. U.S. Pat. No. 5,348,432 also discloses a counterbored tee nut having an octagonal flange. Recently, a patent application was filed disclosing and claiming a square-headed fastener having a shaft with a counterbore intended to be riveted. That application was assigned Ser. No. 10/105,248 and was filed on Mar. 26, 2002.
Typically, tee nuts are flared, whether fully threaded or counterbored, using an anvil and a flaring pin. The flaring pin enters the end of the shaft at an opening distal from the flange and flares the end radially outwardly with respect to an axis of elongation of the shaft. In some cases, when the shaft end is flared, discontinuities are formed about the circumference of the flared portion, although the locations of such discontinuities may not be accurately predicted.
Often, tee nuts that are flared have a flange with pawls or other ribs or projections extending in the same direction of elongation as that of the shaft so that they embed in the surface of the material through which the shaft extends to preclude the shaft from rotating when a threaded fastener is inserted therein. Often, these pawls, ribs or other projections are insufficient to preclude “spin-out” of the shaft when the fastener is inserted and rotated. The flared portion of the shaft is designed solely to preclude the tee nut from being pushed out of the material in which it has been installed. The present invention contemplates enhancing the function of the flared portion of a tee nut shaft so that it performs dual functions, (1) preventing push out, and (2) precluding “spin-out” of the shaft during fastener insertion.
SUMMARY OF THE INVENTIONThe present invention relates to a method of riveting a headed fastener. The present invention includes the following interrelated objects, aspects and features:
(1) The present invention is intended to be used in association with a headed fastener such as a tee nut, but not limited to a tee nut. The present invention is equally usable on counterbored tee nuts as well as those that are fully threaded.
(2) In practicing the teachings of the inventive method, the present invention contemplates embodiments of a riveting pin having protuberances that cause the flared end of the shaft to be flared in one or more discontinuous portions of the circumference of the shaft. In the case of riveting, where the length of the shaft is greater than the thickness of the material through which it extends, the flared discontinuous portions or tangs are of two types, one type that digs into the top surface of the material and a second type that digs into the inner walls of the passage or hole through which the shaft extends. Each type deters “push out” and “spin-out.” Where the shaft is of a length equal to or less than the thickness of the material through which it extends, the discontinuous portion or portions dig into the walls of the passage or hole through which the shaft extends to deter “push out” and “spin-out.”
(3) In explaining the teachings of the present invention, the fastener which is disclosed as an example is a square-headed rivet fastener such as is disclosed in co-pending application Ser. No. 10/105,248. That fastener is counterbored and has a square flange with eight ribs extending upwardly from a top surface of the flange.
(4) Where the length of the fastener shaft is no longer than the thickness of the material through which it is inserted, a first design of flaring pin is provided. Where the length of the shaft of the fastener employed is greater than the thickness of the material through which it extends, a second embodiment of flaring pin is employed. In the former case, in order for the present invention to work, it is only necessary for one discrete portion of the circumference of the shaft to be flared into the wall of the passageway through which the shaft extends. In the latter case, for the invention to operate as intended, it is only necessary for one portion of the circumference of the shaft to enter the wall of the passageway and one other portion of the circumference of the shaft to be folded over and embedded into the exterior surface of the material.
(5) While the fastener example shown in this application is a square-headed rivet fastener, the teachings of the present invention are equally applicable to other kinds of fasteners having a shaft and a flange where the shaft is either fully threaded or counterbored.
As such, it is a first object of the present invention to provide a method of riveting a headed fastener.
It is a further object of the present invention to rivet a fastener comprising a tee nut.
It is a yet further object of the present invention to provide a method of riveting a fastener having any style flange so long as the shaft is elongated and hollow, whether or not counterbored.
It is a yet further object of the present invention to provide such a method applicable to a fastener having a flange and an elongated fully threaded shaft.
It is a still further object of the present invention to provide such a method in which a portion of the circumference of the shaft is bent and forced into a wall of a passageway through which the shaft extends.
It is a still further object of the present invention to provide such a method in which one portion of the shaft is bent and forced into the wall of the passageway through which the shaft extends and another portion of the circumference of the shaft is bent over an outer surface of the material.
These and other objects, aspects and features of the present invention will be better understood from the following detailed description of the preferred embodiments when read in conjunction with the appended drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
With reference, first, to
The flange 11 has a top surface 19 which has, extending upwardly therefrom, a plurality of trapezoidal cross-section ribs of which those shown in
The shaft 13 has an internal chamber 35 including a threaded portion 37 closest to the flange 11 and a counterbored portion 39 nearest to the end of the shaft 13 distal from the flange 11, and which is unthreaded and has a thinner wall 41 than the thickness of the wall where the shaft is threaded at 37.
With reference, now, to
With particular reference to
The portions 75, 77, 79 and 81 of the shaft 13 that are unaltered by operation of the riveting pin 50 are those portions that are located at 65 between adjacent pairs of ribs 63 of the riveting pin 50.
As shown in
Reference is now made to
A reciprocating fitting 7 of the insertion machine carries and reciprocates the fastener 10 in the downward direction in the view of
Reference is now made to
With reference, now, to
The fastener 10 as seen in
This configuration is achieved in the following manner: With reference to
With reference to
With further reference to
If desired, the flaring pin can be designed to cut different adjacent tangs from the shaft and deflect them into the walls of the hole 4 of the substrate 1 at differing heights. Thus, for example, with reference to
When the riveting pin 80 cylindrical shaft 91 enters the passageway 35 within the fastener 10, first, the portion or shoulder 97 engages the entire circumference of the passageway 35 of the shaft 13 of the fastener 10 and flares the entirety thereof to the configuration shown by the portions 105, 109 and 113. Further reciprocation cuts and separates out the eight portions 101-115 and engagement of the ribs 93 on the portions 103, 107, 111 and 115 causes them to further flare to the configuration shown in
In this way, the portions 101, 105, 109 and 113 as well as the portions 103, 107, 111 and 115 act to preclude both “push out” and “spin-out.”
As explained above, the present invention is practiced using fastener insertion machines which are designed to feed a series of fasteners using a feeding mechanism to a location where a reciprocating member inserts each fastener through an opening in a piece of material or workpiece such as, for example, a piece of wood. As the fastener is being inserted through the material, with the flaring pin already inserted into the opening from the other end, the shaft end remote from the flange impacts upon a flaring pin such as is illustrated in
Each of the methods of the present invention begin with attachment of the riveting pin to the anvil of a fastener insertion machine. Once the riveting pin has been so attached, fasteners are fed to a location where they may be reciprocated through an opening in a workpiece through which the riveting pin has already been inserted from the other side. When the fastener reciprocates through an opening formed in a workpiece such as a piece of wood, the end of the shaft thereof remote from the flange engages the riveting pin. In the case of the embodiment of
In the case of the embodiment of
Concerning each method embodiment, once the fastener has been inserted and the distal end of the shaft 13 thereof has been altered in the manner best seen in
Each embodiment of the inventive method has been found to insert and rivet fasteners such as the square-headed fastener shown in
As such, an invention has been disclosed in terms of preferred embodiments thereof, which fulfill each and every one of the objects of the invention as set forth hereinabove, and provide a new and useful method of riveting a headed fastener of great novelty and utility.
Of course, various changes, modifications and alterations in the teachings of the present invention may be contemplated by those skilled in the art without departing from the intended spirit and scope thereof.
As such, it is intended that the present invention only be limited by the terms of the appended claims.
Claims
1. A method of flaring a fastener, including the steps of:
- a) providing a fastener having a flange and an elongated hollow shaft extending from a surface of said flange, said shaft having a passageway extending therethrough and opening at an end of said shaft;
- b) providing a flaring pin having a protrusion sized to be received in said passageway and, below said protrusion, at least one rib extending about a fraction of a circumference of said protrusion, and an open area adjacent said rib;
- c) inserting said flaring pin into a hole through a workpiece;
- d) reciprocating said shaft so that said end of said shaft overlies said protrusion;
- e) further reciprocating said shaft so that said shaft end engages said rib and said rib flares a portion of said shaft engaged by said rib radially outwardly to form a tang partially embedded in said workpiece, other portions of said shaft remote from said rib remaining unflared;
- f) said tang precluding said fastener from being pushed out of said hole or spinning with respect to said workpiece.
2. The method of claim 1, wherein said passageway is fully threaded.
3. The method of claim 1, wherein said passageway is threaded adjacent said flange and unthreaded remote from said flange.
4. The method of claim 1, wherein said passageway is cylindrical.
5. The method of claim 1, wherein said at least one rib comprises a plurality of ribs circumferentially spaced about said circumference, adjacent ribs being separated by a said open area.
6. The method of claim 5, wherein, during said further reciprocating step, said ribs flare circumferentially spaced portions of said shaft.
7. The method of claim 5, wherein said plurality of ribs comprises four ribs.
8. The method of claim 1, wherein said step of providing a flaring pin includes the step of providing said flaring pin with a tapered surface below said at least one rib.
9. The method of claim 8, just after said further reciprocating step, said method includes the step of additionally reciprocating said shaft so that said tapered surface engages a further portion of said shaft unflared by said rib and flares said further portion radially outwardly.
10. The method of claim 9, wherein said at least one rib comprises a plurality of ribs circumferentially spaced about said circumference, adjacent ribs being separated by respective tapered surfaces.
11. The method of claim 10, wherein said plurality of ribs comprises four ribs.
12. The method of claim 1, said tang being embedded within said hole.
13. The method of claim 1, said tang being embedded into an outer surface of said workpiece.
14. The method of claim 10, wherein a length of said shaft is greater than a thickness of said workpiece.
15. The method of claim 14, wherein, during said additionally reciprocating step, portions of said shaft are embedded in an outer surface of said workpiece.
16. The method of claim 15, wherein, during said further reciprocating step, other portions of said shaft are embedded within said hole.
17. A method of flaring a fastener, including the steps of:
- a) providing a fastener having a flange and an elongated hollow shaft extending from a surface of said flange, said shaft having a passageway extending therethrough and opening at an end of said shaft;
- b) providing a flaring pin having a protrusion sized to be received in said passageway and, below said protrusion, a plurality of ribs circumferentially spaced about said circumference, adjacent ribs being separated by respective open areas;
- c) inserting said flaring pin into one end of a hole through a workpiece;
- d) reciprocating said shaft into said hole from another end of said hole so that said shaft end overlies said protrusion;
- e) further reciprocating said shaft so that said shaft end engages said ribs and flares spaced portions of said shaft engaged by said ribs radially outwardly to form spaced tangs partially embedded in said workpiece;
- f) said tangs precluding said fastener from being pushed out of said hole or spinning with respect to said workpiece.
18. The method of claim 17, wherein said passageway is threaded adjacent said flange and unthreaded remote from said flange.
19. The method of claim 17, wherein said step of providing a flaring pin includes the step of providing said flaring pin with tapered surfaces between said ribs.
20. The method of claim 19, wherein, just after said further reciprocation step, said method includes the step of additionally reciprocating said shaft so that said tapered surfaces engage said shaft end and flare other portions of said shaft radially outwardly.
21. The method of claim 17, said tangs being embedded within said hole.
22. The method of claim 17, said tangs being embedded into an outer surface of said workpiece.
23. The method of claim 17, wherein a length of said shaft is greater than a thickness of said workpiece.
24. The method of claim 20, wherein, during said additionally reciprocating step, said other portions of said shaft are embedded in an outer surface of said workpiece.
25. The method of claim 24, wherein, during said further reciprocating step, said portions of said shaft are embedded within said hole.
Type: Application
Filed: Oct 29, 2004
Publication Date: Apr 21, 2005
Applicant:
Inventors: Walter Leistner (Goodwood), Sung Liu (Toronto)
Application Number: 10/975,632