The present invention relates to devices/systems/methods of establishing a physical connection between two objects.
In the prior art, two objects are commonly connected to one another and fixed relative to each other by using nails, bolts and nuts, screws and/or adhesives. For example, in a mailbox post, a substantially vertical wooden beam is commonly attached to a substantially horizontal wooden beam by nails. These prior art connecting systems can be damaged or the objects themselves can be damaged if a sufficient force is applied to one or both objects. For example, if a snow plow strikes the horizontal beam of the mailbox post, the horizontal wooden beam may transmit the force from the snow plow to the nails, the nails may be bent or broken, and the wooden beams (both vertical and horizontal) are often damaged. It would be useful to have a system that will serve to connect two objects (such as the wooden beams of a mailbox post) to each other, and fix those objects relative to each other until a force of sufficient magnitude is applied, and upon the application of such a force, the system would allow the objects to move relative to each other so as to avoid damage to the objects until the force is withdrawn, and then hold the objects again following removal of the force in a manner that facilitates continued use.
The invention may be embodied as a fastener assembly having a spring, a first threaded stud device (the “first stud device”), a second threaded stud device (the “second stud device”), and a rigid shear pin. The first threaded stud device may have (a) a shaft engaged with a first end of the spring, (b) a head piece, and (c) an internally-facing surface defining a passageway that extends through the head piece and the shaft. The second stud device may have (a) a shaft with a first end and a second end, and (b) an end piece. The first end of the second stud device may be engaged with a second end of the spring. The second stud device may include an internally-facing surface defining a hole that extends from the first end toward the second end of the second stud device. The end-piece, which may be a nut or an anchor, may be engaged with the second end of the second stud device. Part of the shear pin resides in the passageway of the first stud device, and a different part of the shear pin engages the second stud device. Also, the shear pin may include a slot on an end of the shear pin that may be used to remove a portion of the shear pin from the second stud device after the shear pin breaks.
The fastener assembly may include a first washer and/or a second washer. If utilized in the assembly, the first washer may reside around a portion of the shaft of the first stud device, and may be located between the head piece of the first stud device and the first end of the spring. When the end piece is a nut, the second washer may reside around a portion of the second stud device, and may be located between the nut and the second end of the spring. When the end-piece is an anchor attached to a wall or ceiling, it may not be necessary to include the second washer. It will be recognized that if the head piece is large enough, it may not be necessary to include the first washer in the assembly. The washers may be used to transfer force from the assembly to the objects (e.g. mailbox posts) that are being held relative to each other by the assembly.
The shaft of the first stud device may have externally-facing threads that engage an internally-facing surface on the first end of the spring. The second stud device may have externally-facing threads that engage an internally-facing surface on the second end of the spring. In this manner, a portion of the first stud device and a portion of the second stud device may each engage the spring, and different portions of the first stud device and second stud device may extend from the spring.
A portion of the shear pin may have an externally-threaded surface that engages the second stud device. The second stud device may have an internally-threaded surface that engages the shear pin. For example, the internally-threaded surface of the second stud device may engage the externally-threaded surface of the shear pin.
The assembly may include devices for preventing part of the shear pin from leaving the assembly when the shear pin breaks. One such device utilizes a retention clip. The shear pin may have a head and an internally-facing surface defining an orifice that extends through the head of the shear pin. A different end of the retention clip may extend around a portion of the head piece. The end of the retention clip that extends through the orifice in the shear pin head may be tied off or knotted so that the clip does not leave the orifice in the shear pin head.
A more complex device for preventing part of the shear pin from leaving the assembly includes a washer residing around a portion of the shaft of the first stud device and located between the head piece and the first end of the spring. The washer has at least two extensions, each of which receives a different end of a retention clip. The retention clip may be positioned to prevent the shear pin from leaving the first stud device. When it is desired to install a shear pin, the retention clip may be rotated aside, without removing the clip from the washer. Once the shear pin is installed, the clip may be rotated back to a position where the clip will prevent a broken portion of the shear pin from leaving the assembly.
The fastener assembly may be used to join two beams of a mailbox post. The first and second beams of the mailbox post may be made of wood. The fastener assembly may be used to keep the beams close to each other so as to facilitate making a mailbox available to postal-service employees. When a force of sufficient magnitude (a “threshold force”) is applied to one of the beams, the shear pin will break, thereby allowing one of the beams to move relative to the other beam without significant damage to either of the beams. After the shear pin breaks, the spring holds the beams to each other in a relatively flexible manner so as to continue providing the mailbox to postal-service employees. To facilitate this functionality, the shear pin may be made from a material that will break prior to damage occurring to the beams.
The fastener assembly may be used to provide support to a support member, such as a pipe hanger. When a force exceeding the threshold is applied to the support member, the shear pin will break, and the spring may then be used to provide support to the support member, albeit in a relatively flexible manner. The shear pin may be made from a material that will break prior to damage occurring to the support member, the anchor, or the object (e.g. a wall or ceiling) in which the anchor is fixed. Since such hangers are often not easily reached, it may be prudent to provide a mechanism by which a maintenance person can determine the state of the shear pin from a distance. Such a mechanism may be a colored surface of the shear pin that is not exposed to view until the shear pin breaks. When the shear pin breaks and comes to rest by way of the retention clip, the colored surface of the shear pin drops away from the spring so that the colored surface becomes visible to maintenance personnel. Upon seeing the colored surface, the maintenance personnel will be alerted to the need to install a new shear pin.
For a fuller understanding of the nature and objects of the invention, reference should be made to the accompanying drawings and the subsequent description. Briefly, the drawings are:
One or more washers (
The bolt 15, spring 20 and stud 25 may be formed from a material that is strong relative to the shear pin 40. For example, the bolt 15, spring 20 and stud 25 may be steel, and the shear pin may be a nylon material. Alternatively, or in addition, a portion of the shear pin 40 may have a reduced diameter so as to serve as a stress concentrator, and thereby facilitate breaking at a particular location of the shear pin 40. In this manner, the shear pin 40 is more likely to break than are the bolt 15, spring 20 or stud 25 when a force is applied to the connector system 10. In one embodiment of the invention, Nylon 66 may be used for the shear pin 40, carbon-steel may be used for the bolt 15 and stud 25, and the spring 20 may be hard drawn, tempered spring steel with a zinc plating.
The threads of the bolt 15 and the threads of the stud 25 may be selected to mate with the coils of the spring 20. The spring 20 may be selected to withstand a desired load, and then the threads of the bolt 15 and stud 25 may be selected to mate with the spring 40. For example, the spring 20 may be made from wire having a diameter of 0.092 inches. That wire may be formed into a four-inch long spring having a 0.750 inch outside diameter so as to support a load of about 31 pounds and yet return to its pre-load shape once such a load is removed. A ⅝-11 bolt having 11 threads per inch (i.e. about 0.091″ thread spacing) may be selected so that the externally-facing threads 75 of the bolt 15 mate with the coils of the spring 20 so that at least part of the spring wire resides the valley created by the crests of the threads. A similarly sized stud 25 may be selected so that the externally-facing threads 75 of the stud 25 mate with the coils of the spring 20. As such, the bolt 15 and the stud 25 may each be turned relative to the spring 20 so as to engage the spring 20 with the threads of the bolt 20 and the stud 25.
One manner of assembling the connector system 10 may involve the following procedure:
Upon breaking, the portion of the shear pin 40 that resides in the passageway 550 of the bolt 15 may have enough energy to eject that portion of the shear pin 40 from the bolt 15. In order to prevent that portion of the shear pin 40 from being ejected, the retention clip (
Ideally, once assembled, the bolt 15 and stud 25 are separated from each other, but each is engaged with a different end of the spring 20. Such an arrangement provides a flexible connection between the bolt 15 and stud 25. The distance between the washers 50 and 55 may be adjusted by turning the bolt 15 and/or the stud 25 relative to the spring 20. When installed, the washers 50, 55 reside near a respective one of the objects so that the position of the objects may be fixed relative to each other. By installing the shear pin 40, the connection between the bolt 15 and stud 25 becomes more rigid so that the relative positions of the objects may be securely held, at least until the shear pin 40 breaks as a result of applying a threshold force to the connector system 10. Once a threshold force (i.e. a force of sufficient magnitude to break the shear pin 40) is applied, the shear pin 40 will break, and the spring 20 then provides a relatively flexible connection between the bolt 15 and stud 25. For example, the horizontal beam of a mailbox post may be held tightly against the vertical beam of the mailbox post until the threshold force is applied, and the shear pin 40 breaks. Once the shear pin 40 is broken, the horizontal beam is allowed to move away from the vertical beam by the applied force.
Once broken, the shear pin 40 can be replaced easily by removing: (a) the second end 90 of the retention clip 45 from the orifice 95 to remove a first portion of the shear pin 40 from bolt 15, and (b) a second portion of the shear pin 40 from the threaded stud 25 by use of a screwdriver in slot 100 of the shear pin 40. Once removed, a new shear pin 40 can be installed and the retention clip 45 can be inserted into the orifice 95 of the new shear pin 40.
The connector system 10 can be used where a flexible connection between two objects is desired in order to prevent damage to the objects when a force of sufficient magnitude is applied to one or both of the objects, but also provide a relatively rigid connection between those two objects under standard circumstances (i.e. when no force or a force less than a threshold magnitude). For example, two objects may be held near each other via the connector system 10. To do so, the bolt-side washer 50 contacts or applies a force to a first one of the objects, and the nut-side washer 55 contacts or applies a force to a second one of the objects so as to place the spring 20 under tension. In effect, the washers 50 and 55 apply forces in opposite directions, each to one of the two objects to be joined, with the spring pulling the objects together. To increase the forces applied to the objects, the nut 30 may be tightened, the bolt 15 may be tightened, or both. As the nut 30 and/or bolt 15 are tightened, the spring 20 extends (thereby increasing the tension) and the spring-diameter attempts to shrink, thereby holding the bolt 15 and threaded stud 25 more tightly. The shear pin 40 may be inserted through the passageway 550 of the bolt 15 and spring 20, and an end of the shear pin 40 may be inserted into the stud 25 until the shear pin threads 110 engage the internally-facing threads 85 of the internally threaded stud 25. The shear pin 40 may be tightened until the washers 50, 55 exert a desired force on the objects.
In one embodiment of the invention, the connector system 10 may be used to join two parts of a wooden mailbox post 200, which is comprised of a vertical beam 205 and a horizontal beam 210. See
With a modification to the mailbox post 200, the connector system 10 can also provide flexibility in response to a vertical force 400 applied to the horizontal beam 210. See
It will now be recognized that in an embodiment of the invention, the dado joint may be manufactured so as to allow the horizontal beam 210 to move relative to the vertical beam 205 when the shear pin 40 has been broken as a result of a force applied to the horizontal beam 210. However, the portion of the dado joint on the vertical beam 205 may be a relatively tight fit with the horizontal beam 210 when vertical rotation of the horizontal beam 210 is not needed. The vertical beam 205 may have angled cuts 220 when it is desired to permit the horizontal beam 210 to rotate vertically relative to the vertical beam 205 if a force is applied from underneath or from above the horizontal beam 210. Regardless of the type of dado joint described above, the connector assembly 10 allows the horizontal beam 210 to rotate relative to the vertical beam when enough force is applied to break the shear pin 40.
The shear pin 40 may have a section 505 (
Although the present invention has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present invention may be made without departing from the spirit and scope of the present invention. Hence, the present invention is deemed limited only by the appended claims and the reasonable interpretation thereof.
This application claims the benefit of priority to U.S. provisional patent application Ser. No. 62/195,491, filed on Jul. 22, 2015.
Number | Name | Date | Kind |
---|---|---|---|
768283 | Jenkins | Aug 1904 | A |
954588 | Randall | Apr 1910 | A |
1220908 | Thomas | Mar 1917 | A |
1434737 | Enzenauer | Nov 1922 | A |
1462925 | Wilburger | Jul 1923 | A |
1561119 | Smith | Nov 1925 | A |
2117701 | Burnett | May 1938 | A |
2138919 | Herman | Dec 1938 | A |
2514394 | Irving | Jul 1950 | A |
2586556 | Mullikin | Feb 1952 | A |
2995330 | Alms | Aug 1961 | A |
3018127 | Dobrosielski | Jan 1962 | A |
3065660 | Puterbaugh | Nov 1962 | A |
3390906 | Wing | Jul 1968 | A |
3419298 | Worley | Dec 1968 | A |
3658284 | Haasl | Apr 1972 | A |
3763402 | Shore et al. | Oct 1973 | A |
3905141 | Chichester, Jr. | Sep 1975 | A |
3943882 | Sollak et al. | Mar 1976 | A |
4004486 | Schenk | Jan 1977 | A |
4437286 | Maguire | Mar 1984 | A |
4686926 | Vance | Aug 1987 | A |
4704748 | Takeda et al. | Nov 1987 | A |
4762453 | DeCaro | Aug 1988 | A |
4779850 | Paton et al. | Oct 1988 | A |
4995576 | Kieswetter | Feb 1991 | A |
5102276 | Gourd | Apr 1992 | A |
5129232 | Minas et al. | Jul 1992 | A |
5248159 | Moore | Sep 1993 | A |
5961266 | Tseng | Oct 1999 | A |
6554526 | Egelandsdal | Apr 2003 | B1 |
6637531 | Palenchar | Oct 2003 | B2 |
7121780 | Matich | Oct 2006 | B2 |
7249923 | Niku | Jul 2007 | B2 |
7601167 | Lieberman | Oct 2009 | B2 |
7789607 | Fuest | Sep 2010 | B2 |
7871251 | Marino et al. | Jan 2011 | B2 |
8355243 | Niedzwiecki | Jan 2013 | B2 |
8434983 | Chen | May 2013 | B2 |
8517649 | Pratt | Aug 2013 | B2 |
8623049 | Ward | Jan 2014 | B2 |
9808106 | Bihn | Nov 2017 | B1 |
10017905 | Young, Jr. | Jul 2018 | B2 |
20080080952 | Cook | Apr 2008 | A1 |
20100143069 | Moore | Jun 2010 | A1 |
20100237143 | LaBrecque, Jr. | Sep 2010 | A1 |
20100282832 | Do | Nov 2010 | A1 |
20140086703 | Thommes | Mar 2014 | A1 |
20140263881 | Bryan | Sep 2014 | A1 |
20150374158 | Schroeder | Dec 2015 | A1 |
20170043209 | Walstead, Jr. | Feb 2017 | A1 |
20170295978 | Bihn | Oct 2017 | A1 |
Number | Date | Country |
---|---|---|
H0495605 | Mar 1992 | JP |
2005325999 | Nov 2005 | JP |
Number | Date | Country | |
---|---|---|---|
62195491 | Jul 2015 | US |