Note: Descriptions are shown in the official language in which they were submitted.
CA 02285135 2003-07-30
29512-12
ELECTRICAL RACEWAY ASSEMBLY
FIELD OF THE INVENTION
The present invention relates to the
electrification of structures, particularly office furniture
and partitions, dividers and panels used to form office
cubicles. Specifically, the invention concerns electrical
raceway systems and covers for raceways to shield cables and
wires housed within.
BACKGROUND OF THE INVENTION
As the cost of doing business has increased due to
increases in costs of personnel, insurance, office space and
the like, a trend for downsizing has developed. This trend
along with the expanding presence of small businesses has
created a pressure for economy in the workplace. Part of
this economy is that a space may be required to fulfill more
than one role. At the same time, an awareness of the
effects of office aesthetics on morale and
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CA 02285135 1999-10-OS
productivity has created a desire for pleasant and efficient workspaces. To
meet these needs, attractive yet portable training, conference and office
furniture is marketed by Versteel, P.O. Box 850, Jasper, IN 47547 (800-
876-2120). Also, in many cases, open office plans must be divided into
individual offices or workstations. Many arrangements are available to
divide an open office space, including partition panels, systems furniture,
and modular furniture.
Such workstations typically require specific features for maximum
functionality: power supply, communication ports and keyboard or other
support tools. However, in open office space, work structures may be placed ,
in locations that are not easily accessible to the office space electrical and
communication ports. Therefore, one challenge with providing power
supply and communication access to the desk top of each workstation is wire
management. Improper wire management can lead to interruptions in
service, workplace hazards and poor aesthetics.
There is a growing need for improved components and systems for
accommodating the distribution of electrical power along or in structures.
Examples of electrical systems in office furniture panels and modular wall
units are disclosed in U.S. Patent Nos. 4,370,008, 5,231,562 and 5,451,101.
Such systems include raceway enclosures for guiding electrical and
communication wires from wall outlets to workstation structures. The
raceway system facilitates the extension of both electrical and
communication cables along the system in an efficient yet hidden manner,
while permitting desired utilization of these cables at selected locations.
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CA 02285135 1999-10-OS
In spite of the benefits of such raceway systems, a need has remained
for systems that improve the usability, flexibility, dependability, appearance
and convenience of such raceway systems, particularly when used with
tables or desks.
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CA 02285135 2004-08-04
29512-12
StII~lARY OF T8E INVENTION
The invention provides an electrical raceway
assembly for use with a structure, comprising: an elongated
raceway engageable to the structure and having a length, a
transverse base and a pair of opposite upstanding sidewalls
extending along said length to define at least one channel
configured for retaining electrical wires; a cover
attachable to said raceway to occlude at least a portion of
said at least one channel, said cover including an elongated
face plate having an interior surface and an exterior
surface, said face plate further having a first portion and
an opposite second portion, each said portion extending
along a length of said face plate and attachment means for
pivotably attaching one of said first and second portions of
said face plate to one of said opposite upstanding sidewalls
so that said interior surface faces said channel; and a
hinge portion integral with said face plate and disposed
adjacent said attachment means.
The invention also provides a multiple durometer
cover for occluding channels in an electrical wire raceway,
comprising: an elongated face plate having an interior
surface and an exterior surface, said face plate further
defining a first portion and an opposite second portion; an
attachment element defined at said first portion for
attaching said face plate to the raceway so that said
interior surface faces the interior of the raceway; and a
hinge portion integral with said face plate and disposed
between said second portion and said attachment element,
said hinge portion having an average durometer relatively
lower than the average durometer of said face plate; wherein
said attachment element is a pivot element configured far
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CA 02285135 2004-08-04
29512-12
pivoting said cover thereabout when said attachment element
is engaged to the raceway.
Briefly describing one aspect of the invention, an electrical raceway
assembly for use with a structure is provided. The assembly includes an
elongated raceway engageable to the structure and having a length, s
transverse base and a pair of opposite upstanding sidewalls extending along
the length to define at least one channel configured for retaining electrical
wires. A cover is attachable to the raceway to occlude a portion of the
channel. The cover includes an elongated face plate having an interior
surface and an exterior surface. The face plate has a first portion and an
opposite second portion, each portion extending along a length of the face
plate. Attachment means are provided for attaching the first and second
portions of the face plate to each of the opposite upstanding sidewalls with
the interior surface facing the channel.
A flange extends from one of the portions of the cover plate and
occludes an area behind the flange when the cover is attached to the
raceway. The flange is relatively more flexible than the other elements of
the cover and elastically deformable to allow access to the area. In some
embodiments, the flange has a lower durometer than the other elements of
the cover, such as the face plate or attachment means. In certain
embodiments, the flange is integral with the face plate. In other
embodiments the flange is adjacent the second portion and the face plate and
is recessed to the face plate.
In another embodiment, one of the side walls of the raceway
terminates in a lip, which includes a rounded surface having a radius. The
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CA 02285135 1999-10-OS
attachment means of the cover includes a groove defined in the first portion
that is configured for snap fit engagement with the lip. In some
embodiments, a second of the side walls of the raceway terminates in an
elongated attachment receptacle and the attachment means of the cover
includes a rounded edge of the second portion that is receivable within the
attachment receptacle. The rounded edge is configured for snap fit
engagement within the receptacle. In specific embodiments the attachment
receptacle defines a curved interior portion having an internal radius
slightly
larger than the radius of the rounded edge for mating with the rounded edge.
In another aspect of the invention, the attachment means includes a hinge
feature. The rounded edge of the second portion is rotatingly receivable
within the attachment receptacle so that the cover is rotatable, about a
longitudinal axis of the attachment receptacle, between an open position in
which a portion of a channel of the raceway is exposed and a closed position
in which the first portion is engaged to the raceway.
In a further embodiment of the invention, an extruded cover includes
an elongated face plate of a sufficient hardness and rigidity to support
electrical receptacles, cover plates and the like. A first portion of the
cover
form a latch to engage on edge of an opening in an electrical raceway. A
second portion is pivotably engaged to an opposite edge of the raceway
opening to the cover can be pivoted between a latched and an unlatched
position, or between a position closing the opening of the raceway and a
position allowing access to the raceway. As with the previous embodiment,
the second portion can include a flange formed of a relatively more flexible,
or lower durometer, material than the face plate.
CA 02285135 1999-10-OS
In this embodiment, the cover includes an additional area of lower
durometer, or greater flexibility, than the face plate. This portion is
situated
between the face plate and the second portion that is rotatably engaged to the
raceway. This additional lower durometer itself acts as a living hinge to
permit pivoting of the face plate relative to the second portion. In certain
applications of the invention, the cover is engaged to a raceway that is
disposed beneath a table or desk surface, with the raceway opening oriented
inward underneath the surface. The living hinge portion allows the cover to
swing completely clear of the raceway opening, even under the table or
desk.
Accordingly, it is one object of the invention to provide improved
electrical raceway systems for work spaces. These and other objects,
advantages and features are accomplished according to the devices and
assemblies of the present invention.
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CA 02285135 1999-10-OS
DESCRIPTION OF THE FIGURES
FIGURE 1 is side sectional view of an electrical raceway assembly
according to one embodiment of the present invention.
FIGURE 2 is a front elevational view of an electrical raceway
assembly.
FIGURE 3 is a side elevational view of a cover for an electrical
raceway according to one embodiment of the present invention.
FIGURE 4 is a partial side sectional view of an electrical raceway.
FIGURE S is a partial side sectional view of a cover for an electrical
raceway.
FIGURE 6 is a partial side sectional view of an electrical raceway
assembly according to one embodiment of the present invention.
FIGURE 7 is a side sectional view of a cover of this invention.
FIGURE 8 is a front elevational view of an electrical raceway
assembly.
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CA 02285135 1999-10-OS
FIGURE 9 is a front elevational view of an assembly according to one
embodiment of this invention.
FIGURE 10 is a side sectional view of a door for a face plate access
doorway according to one embodiment of the present invention.
FIGURE 11 is a partial front elevational view of a cover and door
according to one embodiment of this invention.
FIGURE 12 is a side sectional view of an electrical raceway assembly
according to one embodiment of this invention.
FIGURE 13 is a partial sectional view of an assembly of this
invention engaged to the top of a structure.
FIGURE 14 is a partial sectional view of an assembly of this
invention engaged to the underside of a structure.
FIGURE 15 is a partial sectional view of an assembly of this
invention engaged to the underside of a structure.
FIGURE 16 is a sectional side elevational view of a cover for an
electrical raceway according to a further embodiment of the present
invention.
FIGURE 17 is a sectional side elevational view of the cover shown in
,- FIGURE 16 attached to an electrical raceway.
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CA 02285135 1999-10-OS
FIGURE 18 is a partial section side elevational view of the cover
shown in FIGURE 16 attached to an electrical raceway under a desk surface
with the cover rotated to an open position.
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CA 02285135 1999-10-OS
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
For the purposes of promoting an understanding of the principles of
the invention, reference will now be made to the embodiments illustrated in
the drawings and specific language will be used to describe the same. It will
nevertheless be understood that no limitation of the scope of the invention is
thereby intended. The invention includes any alterations and further
modifications in the illustrated devices and described methods and further
applications of the principles of the invention that would normally occur to
one skilled in the art to which the invention relates.
The present invention provides electrical raceway systems and covers
for raceways that enhance the functionality and aesthetics of workspaces.
The covers are engageable to the raceways in a snap fit engagement that
provides secure placement of the cover and allows removal if access to the
entire raceway is required. The covers are provided with a pliable flange
that occludes an area behind the cover yet allows convenient access to the
area for storing electrical cords and the like.
An electrical raceway assembly 10 for attachment to a structure in
accordance with a preferred embodiment of the present invention is depicted
in Figures 1-5. The system 10 includes an elongated raceway 15
engageable to a structure (not shown), such as a desk, table, wall, panel or
the like. The raceway 15 has a length L, which preferably extends along a
length of the structure to provide power or communication ports at various
locations along the structure. The raceway 15 includes a transverse base
r wall 17 and a pair of opposite upstanding sidewalk 20, 25 extending along
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CA 02285135 1999-10-OS
r..
the length L of the raceway 15. The walls 17, 20, 25 define a channel 30
configured for retaining and guiding electrical and communication wires W
along the length L of the raceway 15. In the embodiment shown in Figure 1,
the channel 30 is U-shaped.
The raceway assembly 10 also includes a cover 40 attachable to the
raceway 15 to occlude at least a portion of the channel 30 to shield or
protect
the contents of the raceway 15 and provide a pleasing appearance to the
assembly 10. The cover 40 includes an elongated face plate 45 having an
interior surface 46 and an exterior surface 47. The cover face plate 45 also
has a first portion 50 and an opposite second portion 55. Each of the
portions 50, 55 extend along a length t of the face plate 45. The length l of
the face plate 45 may be equal or substantially equal to the length L of the
raceway 15 to protect the enclosed wires W and provide a streamlined and
aesthetically pleasing appearance to the structure. In some applications it
may be desirable to provide several covers 40 for a raceway 15 if the
raceway 15 is too long for a single cover 40 to be manageable and
convenient.
Attachment means are also provided for attaching the cover 40 to the
raceway 15. Preferably, the first and second portions 50, 55 of the face
plate 45 are attachable to each of the opposite upstanding sidewalls 20, 25 so
that the interior surface 46 faces the channel 30. The cover 40 is preferably
configured for snap fit engagement with the raceway 15. For example, as
shown in Figure 1, one of the sidewalls 20 terminates in a lip 21. The lip 21
includes a rounded surface 22 having a radius r,. The lip 21 is configured
for mating engagement with attachment means on the first portion 50. In the
embodiment shown in Figures 1 and 3, the attachment means includes a
11
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CA 02285135 2003-07-30
29512-12
~-oove 51 defined in the first portion 50. The groove 51 is configured for.
snap fit engagement with the lip 21. In one specific embodiment, the
attachment means includes an arm 52 that extends along the length l of the.
cover 40 and along with the first portion 50 defines the gioo~e 51. vn
preferred embodiments, the first portion 50 and the arm 52 each terminate in
a rounded edge Sla, 52a, respectively to facilitate engagement of the lip 21.
In the embodiment shown in Figures l and 3, the other side wall 25
of the raceway 15 terminates in an elongated attachment receptacle 26 and
the attachment means of the cover 40 includes a rounded edge 56 of~the
second portion 55. In the particular embodiment shown in Figures 1 and 3,
the wall 57 of the second portion SS is curled to form the rounded edge 56.
The edge 56 is receivable within the attachment receptacle 26 and is
configured for snap fit engagement within the receptacle 26. Preferably, the
attachment receptacle 26 defines a curved interior portion 27 having an
internal radius r; slightly larger than the radius r~ of the rounded edge 56
of
the second portion 55 for mating with the rounded edge 56 as depicted in
Figures 4 and 5.
Preferably, the rounded edge 56 is rotatingly receivable within the
attachment receptacle 26 to facilitate snap fit engagement of the cover 40 to
the raceway 15. In operation, the second portion 55 is first engaged to the
raceway 15 at an angle that facilitates inserting the rounded edge 56 into the
attachment receptacle 26 as shown in Figure 6. The cover 40 is then rotated
along the longitudinal axis Ar (Figure 2) of the receptacle 26 in the
direction
of arrow R until the groove 51 of the first portion a0 contacts the lip 21 of
the side wall 20 and the lip 21 is forced into engagement with the receptacle
26 as shown in Figure 1. The raceway 15 can be conveniently accessed
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CA 02285135 1999-10-OS
without completely disengaging the cover 40 from the raceway 15. The lip
21 is removed from the receptacle 26 and then the cover 40 rotated in a
direction opposite to direction of arrow R. After access is completed, cover
40 is closed as described.
A flange 60 extends from an end of the cover 40 and along the length
l of the cover 40. The flange 60 provides a pass through for excess cord
stored in the area a behind the flange 60 to provide a neat and pleasing work
space. In the embodiment of Figure 3, the flange 60 extends from and is
adjacent to the second portion 55 of the cover 40.
Referring again to Figure 1, the flange 60 is preferably integral with
the face plate 45. In some embodiments, the flange 60 is recessed from the
face plate 45. The flange 60 occludes an area a behind the flange 60 when
the cover 40 is attached to the raceway 15. The flange 60 is relatively more
flexible or pliable than other elements of the cover 40, which must be
sufficiently rigid to prevent inadvertent detachment from the raceway 15.
The flange 60 is elastically deformable to allow convenient access to the
area a for storage of wires on the surface of the structure. That is, upon a .
pulling or pushing pressure, the flange 60 is deformable from its original
shape shown in Figure 1 to a deformed shape that exposes area a. The
flange 60 than returns to its original, undeformed state when the deformation
force is removed. The relative difference in rigidity allows the flange 60 to
bend relative to other stiffer portions of the cover 40 so that the flange 60
is
deformable while the cover 40 remains stationary and engaged to the
raceway 15.
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Providing an elastically deformable flange 60 integrally formed with a
face plate 45 that is sufficiently rigid to maintain engagement with the
raceway 15 can be accomplished by a dual durometer cover 40. The flange
60 preferably has an average durometer which is relatively lower than the
average durometer of other elements of the cover 40, such as the face plate
45 and/or the first and second portions 50, 55 of the cover 40. It is
contemplated that the flanges 60 will be made of a thermoplastic material
having a durometer of less than about Shore 80, preferably from about Shore
30 to about Shore 50, and other portions of the cover 40 will preferably be
made of a thermoplastic material having a durometer at least about 15 units
greater within the range of about Shore 65 to about Shore 95, preferably
from about Shore 80 to about Shore 90. All durometer measurements are in
accordance with ASTMD 224D Shore A, 15 second delay. The dual
durometer covers of this invention can be obtained using methods known in
the art, such as co-extrusion processes.
Although a distinct line 61 is shown in Figures 1 and 2, between face
plate 45 and flange 60, there need not be an exact line between the higher
durometer material and the lower durometer material. If thermoplastic
materials of different durometers are extruded together as is contemplated in
one embodiment of this invention, there will most likely be a fusing of the
materials resulting in a certain amount of blending in the zones between the
higher and lower durometer thermoplastic materials. The exact position of
the line or zone of demarcation between higher and lower durometer
material can vary upward or downward along flange 60 so long as the
objects of the present invention are achieved. Moreover, the blend lines may
be located at different locations on the cover 40 so long as portions of the
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CA 02285135 1999-10-OS
cover 40 are sufficiently rigid to maintain engagement with the raceway 15.
For example, Figure 7 shows blend lines 53, 58 within the first portion 50'
and the second portion 55' of the cover 40' so that the attachment means,
such as the rounded edge 56', are relatively rigid while the flange 60' is
relatively flexible.
The covers of the present invention may be formed of any suitable
material that accomplishes the features of this invention. Preferably, the
covers are composed of a thermoplastic material, including synthetic and
natural rubbers, plastics and the like. The particular material of the covers
is
not critical so long as the covers have portions that are sufficiently rigid
to
maintain snap fit engagement with the raceway until a removal force is
applied, and the flange 60 is elastically deformable to allow temporary
access to an area behind the flange and then return to an undeformed state
occluding the area.
Referring now to Figures 7-9, in some embodiments, the face plate
45' of the cover 40' defines an access doorway 70 for accessing wires W,
electrical outlets 71 and data jacks 72 disposed in the channel of the
raceway. Preferably, the assembly 10' also includes a door 75 detachably
attachable to the face plate 45' to occlude the doorway 70. The door 75
includes front face 76 and a back face 77 so that the back face 77 faces the
channel 30 when the door 75 is attached to the doorway 70.
The assembly 10' preferably includes attachment means for
detachably attaching the door 75 to the face plate 45'. In the embodiment
shown in Figure 7, the attachment means includes a pair of oppositely
spaced latch members 80 projecting outwardly from the back face 77. In
CA 02285135 1999-10-OS
r ~~.
this embodiment, the latch members 80 are perpendicular to a plane of the
door 75. Each of the latch members 80 has a shoulder portion 81 facing the
back face 77 and a groove 82 between the back face 77 and the shoulder
portion 81.
Referring now to Figures 7 and 10, the latch members 80 are
configured for snap fit engagement within the doorway 70. Each pair of
shoulder portions 81 together defines a first dimension Sl that is larger than
a second dimension S2 formed between each pair of grooves 82. The first
dimension Sl is larger than a length Sd of the doorway 70 and the second
dimension S2 is slightly smaller than the length Sd of the doorway 70 so that
.
the door 75 is snap fittable within the doorway 70 to occlude the doorway
70.
Preferably, there is a difference in rigidity between the latch members
80 and the face plate 45' to allow the shoulder portions 81 to be forced past
the smaller dimensioned doorway 70. In one embodiment, the face plate 45'
is relatively more flexible than the latch members 80. This may be
accomplished by using materials having characteristics that influence
rigidity such as thickness and durometer. For example, the face plate 45'
may have an average durometer that is relatively lower than the average
durometer of the door 75.
In this embodiment, the door 75 is substantially or nearly flush to the
face plate 45 so that the assembly 10' has a smooth and streamlined
appearance, which does not detract from the overall aesthetics and
appearance of the work space. At the same time, each of the doors 75 can be
can be opened as desired to provide convenient access to portions of the
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CA 02285135 1999-10-OS
raceway channel 30' so as to permit access to power blocks or
communication cables therein.
In some embodiments as shown in Figure 11, door 75' may be
provided with additional features, such as electrical outlets 78, six-pin
telephone jacks, eight-pin keyed telephone jacks, BNC coaxial data
connectors, dual-coaxial connectors, TNC coaxial data connectors,
subminiature D 25-pin data connectors for twisted pair or ribbon cable,
connectors for fiber optic cables and the like.
In preferred embodiments, the raceway 115 defines at least one other
channel 135 in addition to the first channel 130 as shown in Figure 12. In
some cases it is desirable to house electrical wires in one channel and
communication wires in another. In this assembly 100, the raceway 115,
also includes an open track channel 137 that defines an area a'. Area a' is
partially occluded by flange 160 when the cover 140 is attached to the
raceway 115. In this preferred embodiment, the flange 160 contacts or
approaches the surface 191 of the structure, such as a desk or table 190 as
depicted in Figure 13. The flange 160 provides a visible seal between the
face plate 145 and the surface 191 yet allows access to the open channel 137
to store cords from tools, such as a computer or phone, on the table 190.
The open chamnel 137 can also be used as an additional guide for wires and
cords to desk top tools.
As shown in Figure 13, raceway 115 is fastened to the surface 191 of
a desk, wall, baseboard, or other suitable structure with a suitable fastener
193. In this embodiment, the raceway 115 and cover 140 form a back panel
to the structure 190. The assemblies of this invention may also be fastened
17
CA 02285135 1999-10-OS
below the structure 190 to serve as a modesty panel as shown in Figures 14
and 15. In Figure 14, the open channel 137 is exposed to the area beneath
the structure 190. This configuration is useful in structures defining
grommets (not shown) through the surface for wires to extend from the open
channel 137, through the grommet to the surface 191 of the structure 190. In
Figure 15, the open channel 137 is open behind the structure 190. This
configuration can be used to deliver wires from the open channel 137 to the
back of the structure 190 and onto the surface 191. In embodiments similar
to those shown in Figures 14 and 15, it may be desirable to lengthen the
flange 160 to further occlude the open channel 137 yet still allow access. In
still other embodiments, the assembly 100 can be incorporated into other
structures, such as a wall panel. The flange 160 can be positioned to contact
or approach the floor for capturing excess cords.
The raceways of this invention are preferably formed of a suitable
rugged sheet metal material capable of being easily formed and shaped but
not readily bent or abused. Any suitable tough, resilient material which
possesses form-sustaining rigidity upon being formed and which exhibits
sufficient flexibility to provide the connection upon installation as
described
may be used to form the assembly.
In a further embodiment of the invention, a raceway cover I70,
depicted in Figure 16, is provided that includes an additional region of
greater flexibility. The cover 170 includes a face plate 171, an upper portion
172 and a lower portion 173. The upper portion 172 can be configured like
the first portion 50 of the cover 40 shown in the previous figures. Likewise,
the lower portion 173 can be configured according to the second portion 55
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CA 02285135 1999-10-OS
of the previous cover 40 to include the rounded edge 174 and the flexible
flange 175.
As thus far described, the cover 170 is similar to the cover 40 and can
be used in the same manner. As shown in Figure 14, the cover 40 or 170
can be engaged to a raceway 115 mounted underneath a surface of a desk or
table. As illustrated in this figure, the raceway opens underneath the table
to
fully conceal the sockets, cables and wires contained by the raceway 115. In
order to gain access to the raceway, the cover 40 can be pivoted upward
about its rounded edge 56. However, with the cover 40 of the previous
embodiment, the underside surface 195 of the table 190 restricts how far the .
cover 40 can be rotated, which thereby restricts access to the raceway 115.
In order to address this difficulty, the cover 170 of the embodiment
shown in Figure 16 includes an additional portion 177 of greater flexibility
between the face plate 171 and the lower portion 173. The portion 177 acts
as a living hinge to be resiliently deformed so that the face plate 171 can
pivot relative to the lower portion 173.
In one operative position shown in Figure 17, the cover 170 is
engaged at its upper portion 172 and lower portion 173 to a raceway 15.
The cover 170 can be similarly engaged to a raceway 115, as shown in
Figure 18. In this operative position, the hinge portion 177 is flexed or bent
at generally a right angle. In this position, the cover 170 is firmly engaged
to the raceway to form the channel 30.
When the cover 170 is used with a raceway 115 mounted underneath a
table 190, as shown in Figure 18, the living hinge portion 177 exhibits its
additional functionality. In particular, the face plate 171 can be rotated in
19
CA 02285135 1999-10-OS
,,.-. ....,
the direction of the arrows R about the hinge portion 177. With this motion,
the lower portion 173, and particularly the rounded edge 174 need not pivot
about the raceway 115. The face plate 171 can be pivoted further about the
living hinge 177 until the cover is in the position 170'.
If it is desired, the cover 170 can be pivoted about the lower portion
173 while the face plate 171 is pivoted relative to the living hinge portion
177 to reach the position 170". In this position, the end of the cover 170"
can be just at the bottom surface 195 of the desk or table 190. The living
hinge 177 thus allows the cover 170 to be moved completely clear of the
opening of the raceway 115 to permit unfettered access to the electrical
components housed therein.
The present invention economically and conveniently provides
accommodations for electronic equipment in work spaces, which enhance
the utility of office structures. The raceway assemblies of this invention
guide wires to their outlets and provide table top access to power supply and
communication ports. The devices of the present invention enhance the
utility of office structures in an aesthetically pleasing manner and improve
the quality of the work environment.
While the invention has been illustrated and described in detail in the
drawings and foregoing description, the same is to be considered as
illustrative and not restrictive in character. It should be understood that
only
the preferred embodiments have been shown and described and that all
changes and modifications that come within the spirit of the invention are
desired to be protected.
