Multi-tiered electrical system for furniture

A multi-tiered electrical system is provided for furniture arrangements and the like of the type having a plurality of individual furniture units interconnected side-by-side. A branch raceway extends along each furniture unit, and houses therein an associated branch powerway, which is connected with adjacent branch powerways to create a branch circuit. Power taps are connected to the branch circuit to provide conventional low current power to electrical appliances. A feeder raceway extends adjacent each branch raceway, and houses therein a feeder harness that is connected by a power-in connector to a source of high current electrical power. A power jumper interconnects the feeder harness with one of the branch powerways, such that multiple branch circuits can be powered by a single power-in connector through the feeder harness.

BACKGROUND OF THE INVENTION 
The present invention relates to the electrification of office furniture 
and the like, and in particular to a multi-tiered electrical system 
therefor. 
Open office plans are well known in the art, and generally comprise large, 
open floor spaces that are divided into individual offices or 
workstations. Several different furniture arrangements are presently 
available to divide open office space, including partition panels, systems 
furniture, and modular furniture. Such office furniture is preferably 
capable of being electrified in some fashion, so as to provide electrical 
power at the various workstations for computers, typewriters, dictating 
equipment, and other electrical appliances. 
Many different wiring systems for such office furniture units are currently 
available. Office furniture wiring systems employ different techniques and 
arrangements to conduct electrical power through the office furniture 
units, and to electrically interconnect adjacent office furniture units. 
Convenience and versatility in both in-line and branched configurations 
are important design considerations, as well as electrical integrity, 
durability and overall safety. 
The number of electrical taps or outlets that can be connected with a 
single circuit or power line in a furniture system is normally quite 
limited due to code requirements, and other similar factors. Hence, in 
areas of high power usage, multiple power-in lines must typically be run 
from the building source into the furniture system to provide adequate 
power. Such power-in lines are normally run downwardly from the building 
ceiling and/or upwardly through the building floor, which can detract 
rather substantially from the appearance or aesthetic plan of the office 
space. Also, because power-in passageways through the building floor can 
adversely affect its structural integrity, they are normally restricted in 
number and location, and may even be prohibited, particularly in older 
and/or heavily used spaces in which the furniture has already been 
reconfigured several times Both ceiling and floor power-in points are also 
rather expensive to provide, and therefore reduce the overall cost 
effectiveness of the furniture system. 
SUMMARY OF THE INVENTION 
One aspect of the present invention is to provide a multi-tiered electrical 
system for furniture arrangements and the like. A branch raceway extends 
along each furniture unit, and houses therein an associated branch 
powerway where power access is desired, which is connected with adjacent 
branch powerways to create a branch circuit Power taps are connected to 
the branch circuit to provide conventional low current power to electrical 
appliances. A feeder raceway extends adjacent at least a portion of the 
branch raceway, and houses therein a feeder harness that is connected by a 
power-in connector to a source of high current electrical power. A power 
jumper interconnects the feeder harness with one of the branch powerways, 
such that multiple branch circuits can be powered by a single power-in 
connector through the feeder harness. 
The principal objects of the present invention are to provide a 
multi-tiered electrical system for furniture arrangements and the like, 
which reduces the number of requisite power-in points from the building 
source, so as to improve ease of installation and reduce the associated 
costs. The electrical system is quite versatile, reliable and durable, as 
well as safe. The electrical system is particularly beneficial in 
upgrading the electrical power capabilities of electrical systems in older 
buildings and other similar spaces, especially where power-in points are 
necessarily limited by structural and/or aesthetic considerations. The 
electrical power system is economical to manufacture, capable of a long 
operating life, particularly well adapted for the proposed use. 
These and other advantages of the invention will be further understood and 
appreciated by those skilled in the art by reference to the following 
written specification, claims, and appended drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
For purposes of description herein, the terms "upper", "lower," "right," 
"left," "rear," "front," "vertical," "horizontal," and derivatives thereof 
shall relate to the invention as oriented in FIGS. 1 and 3. However, it is 
to be understood that the invention may assume various alternative 
orientations and step sequences, except where expressly specified to the 
contrary It is also to be understood that the specific devices and 
processes illustrated in the attached drawings, and described in the 
following specification are simply exemplary embodiments of the inventive 
concepts defined in the appended claims. Hence, specific dimensions and 
other physical characteristics relating to the embodiments disclosed 
herein are not to be considered as limiting, unless the claims expressly 
state otherwise. 
The reference numeral 1 (FIG. 1) generally designates a multi-tiered 
electrical system embodying the present invention. Electrical system 1 is 
particularly adapted for use in conjunction with furniture arrangements 
and the like, such as systems furniture, freestanding modular furniture, 
and the illustrated panel system 2 (FIG. 3), which includes a plurality of 
individual panels 3 interconnected in a side-by-side relationship. A 
branch raceway 4 (FIG. 1) extends along each partition panel 3, and houses 
therein an associated branch powerway 5, which is connected with adjacent 
branch powerways to create a branch circuit. Power taps or receptacles 6 
are connected to the branch circuit to provide conventional low current 
power to electrical appliances, and the like. A feeder raceway 7 is also 
provided in each partition panel 3, positioned adjacent branch raceway 4, 
and houses therein a feeder harness 8 that is connected by a power-in 
connector 9 to a source of high current electrical power. A power jumper 
10 interconnects feeder harness 8 with one of the branch powerways 5, such 
that multiple branch circuits can be powered by a single power-in 
connector 9 through feeder harness 8, thereby greatly reducing the number 
of requisite power-in points 
The illustrated partition panel 3 (FIGS. 1 & 2) has a generally rectangular 
front elevational configuration, comprising an upper portion 18, and a 
lower base portion 19. The upper portion 18 of partition panel 3 is 
defined by a marginal upper edge 20, a lower edge 21 and opposite side 
edges 22. Preferably, partition panel upper portion 18 has an acoustical 
interior construction (not shown) enclosed by a pair of decorative outer 
faces or covers 23, which may include wood, synthetic laminates, 
upholstery, or the like. 
The base portion 19 (FIGS. 1 & 2) of partition panel 3 is positioned 
directly below the upper portion 18 thereof, and supports panel 3 
freestanding on a floor surface. In the illustrated example, panel base 
portion 19 includes a pair of vertical legs 24 and 25, which have their 
upper ends 26 fixedly mounted in panel upper portion 18, and their lower 
ends 27 provided with vertically adjustable glides or feet 28. Two 
horizontally extending plates or trays 29 and 30 are mounted on panel legs 
24 and 25 in a vertically stacked relationship, and serve to in part 
define branch raceway 4 and feeder raceway 7. Both upper and lower trays 
29 and 30 extend horizontally to the opposite side edges 22 of panel upper 
portion 18, and are arranged in a generally parallel relationship with the 
lower edge 21 thereof. In the illustrated example, feeder raceway 7 
extends along and immediately above branch raceway 4 to facilitate 
interconnecting power jumpers 10 therebetween It is to be understood that 
the term "raceway", as used herein, also includes other structural 
arrangements which serve to form a channel or conduit for utilities, 
including cable and power lines, and that the relative position of 
raceways 4 & 7 could be reversed. 
As best illustrated in FIG. 2, panel legs 24 and 25 each have a double 
recessed or offset side elevational configuration, comprising inclined 
portions 31 and 32 connected with rear wall portions 33 and 34, which are 
specially shaped so as to prevent the panel legs 24 and 25 from 
interfering with free access through associated raceways 4 and 7. Lower 
tray 30 (FIGS. 1 & 2) of panel base 19 includes a pair of clips 35 mounted 
thereon, with tabs 36 that extend laterally outwardly on opposite sides of 
partition panel 3. A pair of branch raceway covers 37 are provided to 
selectively enclose the opposite sides of branch raceway 4, and extend 
horizontally between the opposite ends of upper and lower trays 29 and 30, 
and vertically between the same. Branch raceway covers 37 are detachably 
mounted to panel base 19 by clip tabs 36, and can be readily removed 
therefrom to access the branch powerways 5. 
The illustrated upper tray 29 (FIGS. 1 & 2) of panel base 19 includes a 
cutout 44 through one side edge thereof, so as to form a vertical 
passageway between branch raceway 4 and feeder raceway 7. Fastener 
apertures 45 are positioned adjacent cutout 44, and serve to mount thereon 
an associated power jumper 10, as described in greater detail hereinafter. 
Cutout 44 is preferably covered by a knockout or removable cover plate 
when not being used with a power jumper 10, so as to maintain isolation 
within raceways 4 and 7. A pair of feeder raceway covers 46 are provided 
to selectively enclose the opposite sides of feeder raceway 7, and extend 
horizontally between the opposite ends of upper tray 29, and vertically 
between upper tray 29 and the lower edge 21 of panel upper portion 18. 
Fasteners 47 detachably mount feeder raceway covers 46 to panel base 19, 
so as to provide access to feeder harness 8, as described in greater 
detail hereinafter. Preferably, fasteners 47 are of the type which require 
a tool from removal, such as the slotted head screws illustrated, so as to 
provide electrical safety, and avoid inadvertent opening of feeder raceway 
7. 
Branch powerway 5 (FIGS. 1 & 2) is preferably a modular unit which is 
received in the branch raceway 4 of an associated partition panel 3, and 
is adapted to quickly interconnect with adjacent like branch powerways 5. 
The illustrated branch powerway 5 comprises a unique construction, which 
is fully disclosed in U.S. Pat. No. 5,092,786 dated Mar. 3, 1992 to Juhlin 
et al, which is commonly assigned, and hereby incorporated herein by 
reference. The illustrated branch powerway 5 includes a housing 50 shaped 
to be received within the branch raceway 4 of an associated partition 
panel 3. A power terminal 51 is mounted in one end of housing 55, and 
includes multiple sets of quick-disconnect power connectors 56 through 59. 
positioned on the opposite faces thereof. Power connectors 57 and 58 are 
configured to separably mate with receptacles 6. A flexible flag connector 
60 is mounted at the end of power terminal 56, and includes a flag 
terminal 61. A receptacle-only terminal 62 is mounted at the opposite end 
of housing 55, and includes two sets of quick-disconnect power connectors 
63 and 64 on opposite faces thereof in which receptacles 6 can be received 
A flag connector 65 is mounted on the end of receptacle-only terminal 62, 
and includes a flag terminal 66 with a set of quick-disconnect power 
connectors that separably mate with the quick-disconnect power connectors 
56 and 59 on the power terminal 56 of an adjacent branch powerway 5 to 
electrically interconnect the same. 
With reference to FIG. 2, each branch powerway 5 includes a plurality of 
electrical conductors 70 extending between opposite ends thereof, which 
are adapted to carry conventional low current electrical power therein for 
office appliances, and the like. For purposes herein, the term "low 
current electrical power" refers to conventional power for standard 
appliances, such as typewriters, dictation equipment, personal computers, 
etc., such as a typical 110 Volt AC, 15-20 amp line. In the illustrated 
example of branch powerway 5, eight conductors 70 are provided, and 
arranged to provide three power circuits, with common neutral and ground 
wires with a maximum of 20 amp, 110 Volt AC per circuit. Other forms and 
configurations of branch circuits and/or powerways are also contemplated 
by the present invention. 
Feeder harness 8 (FIGS. 1 & 2) comprises a plurality of feeder conductors 
75 configured to provide at least one high current circuit that supplies 
power to the various branch circuits. The illustrated feeder harness 8 
includes a shielded cable 76 which extends through the feeder raceway 7 in 
panel system 2. One end of cable 76 is connected with power-in connector 
9, which is in turn connected with a source of high current electrical 
power from the building supply, or the like. The illustrated power-in 
connector 9 comprises a hard wired connection with the building source at 
a floor post or tombstone 77. A conventional top power-in arrangement (not 
shown), or other similar arrangement may also be provided to operably 
connect one end of feeder harness 8 to a source of high current electrical 
power. For purposes herein, the term "high current electrical power" 
refers to the power in a feeder circuit with overcurrent protection 
greater than 20 amps, such that the circuit would not qualify as a general 
purpose branch circuit under the National Electric Code, by virtue of the 
rating of the overcurrent protector. 
Cable 76 includes a feeder harness 8 at each location in which a new low 
current circuit is required for branch powerways 5. In the example 
illustrated in FIG. 3, a single feeder harness 8 provides electrical power 
to three sets of branch powerways 5, wherein each set includes three 
separate branch powerways 5. Three power jumpers 10 are required in this 
configuration, wherein each has a substantially identical construction, as 
described in greater detail below. Where longer runs of panels 3 are 
provided, feeder hardness 8 may have two high current circuits, which are 
individually tapped at various points therealong by power jumpers 10 to 
provide electrical power to multiple sets of branch powerways 5 through a 
single power-in point or connector 9. Also, feeder harness 8 may have a 
modular construction (not shown) similar to that o branch powerways 5. 
With reference to FIGS. 3-6, each power jumper 10 is an assembly which 
includes a shielded connecter box 80 having a marginal base flange 81 with 
fastener apertures 82 therethrough that mate with apertures 45 in upper 
tray 29 to securely fasten the connector box thereto by suitable fasteners 
(not shown). Knockout plugs 83 are provided in the opposite end walls 84 
of connector box 80, through which feeder harness cable 76 is received. 
Connector box 80 houses an overcurrent protection device, such as the 
illustrated conventional circuit breaker 85, and may also optionally house 
a conventional transformer 11, as discussed in greater detail below. Power 
jumper assembly 10 also includes a jumper harness 86 (FIGS. 1 & 2), which 
has one end thereof electrically connected with circuit breaker 85 in 
connector box 80, and has a quick-disconnect connector 87 mounted on the 
free end thereof to mate with connectors 56-59 on the power terminal 56 of 
an associated branch powerway 5. Jumper harness 86 is preferably flexible, 
and is received in, and extends through the cut out 44 in upper raceway 
tray 29, between branch raceway 4 and feeder raceway 7. 
The feeder circuit serves to locate high current electrical power directly 
in the panel system, so as to greatly reduce the number of individual 
wires or conduits running between the building power source and any given 
furniture arrangement. As noted above, the feeder circuit may take the 
form of a 110 VAC arrangement with a relatively high amp service, such as 
100 amp, 80 amp, 60 amp, etc. In these cases, each power jumper 10 need 
only be provided with an appropriate overcurrent protection device, such 
as 20 amp circuit breaker 85 which makes the subsequent or downstream 
portion of the branch circuit conform to certain National Electrical Code 
rules and definitions. In accordance with these rules and definitions, a 
multiplicity of such connectors may be used to power a multiplicity of 
such branch circuits from a single power-in connector and feeder harness. 
In some special circumstances, the feeder circuit may take the form of a 
220 VAC arrangement, in which case, each power jumper 10 also requires a 
transformer 11. In either case, the feeder circuit greatly simplifies the 
wiring necessary to provide adequate power to a selected furniture system. 
In operation, multi-tiered electrical system 1 is installed in panel system 
2 in the following fashion. With reference to FIG. 3, branch powerways 5 
are first installed in the adjacent branch raceways 4 of partition panels 
3, and interconnected in the manner described above. Panel system 2 is 
configured in accordance with the workstations desired, which in the 
example illustrated in FIG. 3, includes three separate circuits to provide 
adequate power to the various workstations. Each of the three circuits is 
supplied by a single high current power source from power-in connector 9 
through feeder harness 8. The first panel in each of the three circuit 
sets is provided with a power jumper 10. A connector box 80 is mounted to 
the upper tray 29 thereof adjacent cutout 44. Feeder harness cable 76 is 
electrically connected at tombstone 77 to the building source (i.e. 100 
amp, 80 amp, 60 amp, etc.) by power connector 9, and is electrically 
connected with each of the power jumpers 10. For each power jumper 10, the 
connector 87 on jumper harness 86 is attached to one of the connectors 
56-59 on the power terminal 56 of the associated branch powerway 5. In the 
special case of voltage transformed power, the transformer 11 of each 
power jumper 10 provides the associated branch powerway circuit with a 
maximum of 20 amps of 110 Volt AC electrical power, which is in turn 
regulated through the associated circuit breaker 85. 
The multi-tiered electrical system 1 thereby reduces the number of 
requisite power-in points with the building source to improve ease of 
installation and reduce associated costs, without any reduction of power 
capabilities. Multi-tiered electrical system 1 is particularly beneficial 
in upgrading the electrical power capabilities of systems in older 
buildings and other spaces, especially where power-in points must be 
limited by structural and/or aesthetic considerations. 
In the foregoing description, it will be readily appreciated by those 
skilled in the art that modifications may be made to the invention without 
departing from the concepts disclosed herein. Such modifications are to be 
considered as included in the following claims, unless the claims by their 
language expressly state otherwise.