Mounting fastener for grounding daisy chain connected building entrance protectors

A fastener for simultaneously mounting adjacently disposed building entrance protectors (BEP) units to a mounting panel and for grounding the units to each other. The fastener includes a tapered and preferably threaded shaft for facilitating securement of the fastener into the mounting panel, such as by screwing or the like. A lip is integrally formed on the shaft and a clamping element, such as a nut, is movably engaged with an untapered opposite end of the shaft so that when rotated about the shaft opposite end, the nut is translated into close proximity with the lip. When mounting tabs from adjacent BEP units are placed between the nut and lip, and the nut is then rotatably tightened, the mounting tabs are placed in electrical contact to provide a grounding connection between the BEPs while securing the adjacent BEPs to the mounting panel.

BACKGROUND OF THE INVENTION 
I. Field of the Invention 
The present invention concerns devices for protecting telecommunications 
equipment from voltage spikes, current overload or sneak current. More 
particularly, the present invention relates to a device for connecting 
building entrance protectors to each other. Most particularly, the present 
invention is directed to a fastener construction for connecting and 
maintaining daisy-chain connections between adjacent building entrance 
protectors to protect terminal equipment from voltage spikes. 
II. Description of the Related Art 
Building entrance protectors (BEP) are commonly used as an interface 
between communication lines from a central office and communication lines 
in an indoor environment, as for example in office buildings, apartment 
buildings, etc. The communication lines from a central office and, in the 
case of a business office, local inter-office lines that connect to 
terminal devices in an office environment, are connected to BEP units. BEP 
units have mounting tabs and are typically mounted in a wiring room or 
closet and fastened by their mounting tabs to panels such as plywood 
boards, etc., by fasteners placed through the mounting tabs. It is 
essential for terminal device equipment protection that the BEP units are 
grounded so that they provide a discharge path for voltage surges or 
spikes, current overloads or sneak current that may occur in the building 
from other equipment or from a lightning strike on a central office line, 
and which would otherwise damage terminal device equipment connected to 
communication lines through the BEP units. 
A problem arises with BEP installation in that a first BEP is typically 
fastened to a panel and grounded by a wire, and then other BEP units are 
sequentially connected to the first BEP unit in a line or "daisy chained" 
together. To provide for a common ground between a plurality of BEP units, 
a small wire usually connects a first BEP to a second BEP, a second BEP to 
a third, etc., with only the initial (e.g. first) BEP unit connected 
directly to the building or earth ground. Such a daisy-chain connecting 
technique introduces difficulties because, often times interconnecting BEP 
grounding wires are inadvertently or carelessly disconnected or are 
omitted which eliminates the safety ground from one or more of the BEPs in 
the chain. As a result, some of the BEPs and the terminal devices 
connected thereto will become or remain ungrounded and thus susceptible to 
damaging voltage spikes, current overload and sneak current. 
SUMMARY OF THE INVENTION 
The present invention provides a securing fastener which provides for 
daisy-chain mounting of BEP units to each other and to a mounting surface 
to ensure electrical grounding interconnection between successive or 
adjacent BEPs. The inventive fastener includes a shaft portion dimensioned 
for insertion onto fastening tabs that are integral with the BEPs. The 
shaft portion contains an integrally formed lip or washer and a screw 
section which is configured for engaging a mounting panel for securing the 
fastener to the panel. A clamp element is positioned on the shaft portion 
and is movably engageable with and in a direction toward the lip. In use, 
the fastener is secured to a mounting board and tabs from adjacent ends of 
adjacent BEPs are placed over the fastener and positioned between the lip 
and the clamp element. The tabs are preferably configured with a key-hole 
shape for this purpose. When so positioned, the clamp element is tightened 
to secure and maintain the adjacent tabs in contact with each other. In a 
preferred embodiment, the fastener has a notched end for facilitating the 
use of a screwdriver to secure the fastener to a substrate or mounting 
board, and a nut fixed to the lip for accommodating use of a wrench to 
secure the fastener in place. 
Other objects and features of the present invention will become apparent 
from the following detailed description considered in conjunction with the 
accompanying drawings. It is to be understood, however, that the drawings 
are designed solely for purposes of illustration and not as a definition 
of the limits of the invention, for which reference should be made to the 
appended claims.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS 
With reference now to the drawings, an inventive BEP fastener 10 in 
accordance with a preferred embodiment of the present invention is 
depicted in FIG. 1. As there shown, the fastener 10 includes a shaft 12 
having a tapered portion 14 with threading 15 and a pointed end 16. The 
threading and pointed end facilitate mounting of the fastener to and into 
a surface, such as by screwing or rotation of the fastener. As also shown, 
fastener 10 has an engaging end 18 in which a notch or groove 20 is 
defined for facilitating mounting of the fastener, as by accommodating use 
of a torque applying tool such as a screwdriver. A radially-outwardly 
extending, and preferably a circumferentially continuous and/or annular 
stop element 22 such as a lip or washer or nut having an upper surface 23 
is preferably integrally formed with the shaft 18 and positioned at the 
beginning or top of the tapered portion 14 as depicted in FIG. 1. Lip 22 
serves, inter alia, as a stop for preventing an excess length of shaft 18 
from entering mounting panel 108 (FIG. 2). A clamp element 24 such as a 
nut is positioned radially about shaft 12 proximate the engaged end 18. In 
a preferred form, nut 24 is threaded and engages threading 26, as is known 
in the art, so that when torque is applied to nut 24 in one direction it 
is translated along the end of shaft 12 into close proximity to stop 
element or lip 22 and more specifically, the bottom or lower surface 28 of 
nut 24 is advanced into close proximity to upper surface 23 of lip 22. As 
will hereinafter become apparent, nut 24 will operatively clamp an element 
to lip 22 when appropriate torque is applied to the nut. 
The intended use of inventive fastener 10 for daisy-chain mounting of 
adjacent BEP units is shown in FIG. 2. As there seen, a first BEP 102 and 
a second BEP 104 are daisy-chain mounted to a common mounting panel or 
substrate or board 108. Each BEP unit has lower slot or key-hole shaped 
mounting tabs 106 (i.e. one tab positioned at each end), and may also 
include similar-shaped upper tabs 107 for vertical stacking of additional 
BEP units as is known in the art. To thus secure the BEPs 102, 104 to the 
board 108, a fastener 10 is secured to board 108 in a known manner, e.g. 
by screwing or hammering, in the predetermined location on board 108 at 
which it is desired to mount a BEP unit so that the lip 22 sits snugly 
against the surface of board 108. Once the fastener 10 is in place, the 
confrontingly opposed mounting tabs 106 of BEP units to be adjacently 
located on the mounting board are positioned between lip and nut 24 such 
as by sliding the tabs around the upstanding post 12 (for a slot type 
mounting tab) or by lowering tab 106 over the post or shaft 12 of fastener 
10 (for a key-hole tab). Once thusly in place, nut 24 is rotatably 
tightened to clamp the adjacent tabs together between surface 28 of the 
nut and surface 23 of the lip. 
Region X of FIG. 2 is shown in further detail in FIG. 3, in which adjacent 
tabs 106 from adjacent BEP unit 102, 104 are seen connected together by a 
common fastener 10 that also secures the tabs to the mounting panel 108. 
As will be appreciated, the engagement of the fastener 10 to mounting 
panel 108 may loosen over time as a result of the properties of the 
material from which the panel 108 is constructed, e.g. wood. However, 
inasmuch as the lip and nut combination are formed of a stronger material, 
such as steel, than the mounting panel, should the fastener loosen over 
time, the overlaying and commonly secured tabs 106 will nevertheless 
remain in contact with each other by virtue of the clamping force applied 
between nut 24 and lip 22. Thus, the required grounding of adjacent tabs 
and BEP units is maintained. In this manner, BEP units can be readily 
daisy-chain connected without having to separately connect individual or 
discrete grounding wires between them. Only a single grounding wire 
connecting one of the BEPs to ground is required to assure grounding of 
all of the BEPs in the chain. 
An alternative embodiment of the inventive fastener is depicted in FIG. 4. 
As there shown, the modified fastener 10' includes a mounting device 30 in 
lieu of or in addition to the groove 20. A mounting device 30, such as a 
nut, is permanently affixed to or molded or fabricated onto or with lip 22 
to allow the lip 22 to be grasped for applying a rotational torque to the 
fastener 10', thus facilitating mounting of the fastener 10' into mounting 
panel 108. Fastener 10' can accordingly be inserted into and affixed to 
panel 108 by using a wrench that grasps the mounting device 30 to apply 
torque to device 30, or by using a screwdriver which applies torque to the 
fastener 10' via groove 20. Also as shown in the alternative embodiment of 
FIG. 4, the fastener 10' need not have tapered walls but may simply have a 
pointed end 16 to facilitate mounting into panel 108. 
Thus, while there have shown and described and pointed out fundamental 
novel features of the invention as applied to a preferred embodiment 
thereof, it will be understood that various omissions and substitutions 
and changes in the form and details of the devices illustrated, and in 
their operation, may be made by those skilled in the art without departing 
from the spirit of the invention. For example, it is expressly intended 
that all combinations of those elements which perform substantially the 
same function in substantially the same way to achieve the same results 
are within the scope of the invention. Moreover, it should be recognized 
that structures and/or elements and/or method steps shown and/or described 
in connection with any disclosed form or embodiment of the invention may 
be incorporated in any other disclosed or described or suggested form or 
embodiment as a general matter of design choice. It is the intention, 
therefore, to be limited only as indicated by the scope of the claims 
appended hereto.