Note: Descriptions are shown in the official language in which they were submitted.
1103~4,3
The present invention relates to luminaire supports
and more particularly concerns apparatus for raising and lowering
a ring-like luminaire support on a pole while maintaining alignment
of the luminaire support relative to the pole.
It is an object of the presen-t invention to provide
an improved apparatus of the above type to maintain the ring-like
luminaire support substantially coaxial wi-th the pole on which it is
mounted as the support is raised and lowered on -the pole.
Another object of the invention is to provide apparatus
of the above type which accommodates to poles of different diameter
and to portions of the same pole of different diameter.
It is a further object of the invention to provide
apparatus of the above type which avoids contact of the support ring
with the pole and thereby prevents shock to the luminaires by such
impact.
Still another object of the invention is to provide
apparatus of the above type which is simple in construction, readily
assembled and reliable in operation.
Other objects and advantages will become apparent
from the following description and the appended claims.
With the above objects in view, the present invention
relates to a centering apparatus for maintaining a ring-like luminaire
support substantially coaxial with a pole on which the support is
adopted to be mounted comprising, in combination, a ring-like support
member, a plurality of generally U-shaped guide members each having
opposite arms securing the guide members at circumferentially spaced
locations on the support member for movement of the guide members
toward and away from the axis of the support member, resilient means
on the arm members constantly urging the respective guide members
toward the axis of the support member for yieldably engaging the
proximate surface of the pole, whereby when the ring-like support
member is mounted encircling the pole and moved up and down therealong,
-1-
1~9~43
the support member is au-tomatically maintained in substantial coaxial
alignment with the pole.
The invention will be bet-ter understood from the fol-
lowing description taken in conjunction with the accompanying drawings,
in which:
Figure 1 is a view in elevation of an annular luminaire
support mounted on a pole with means for raising and lowering the sup-
port, and having a cen-tering apparatus in accordance wi-th the invention;
Figure 2 is a view of the upper portion of the pole
showing in elevation the annular luminaire support and centering apparatus
associated therewith;
Figure 3 is a plan view of the centering apparatus taken
along the line 3-3 of Figure 2;
Figure 4 is a plan view of a portion of the centering
apparatus showing a modification of the apparatus shown in Figure 3;
Figure 5 is a plan view of a portion of the apparatus
shown in Figure 3 showing a modification thereof; and
Figure 6 is a view in elevation of the modification
shown in Figure 5.
Referring now to the drawings, and particularly to
Figure 1, there is shown light pole 1 of high-mast type which is of
tubular shape tapering somewhat toward its upper end. Mounted on the
top of pole 1 is head plate 6 with associated cover 6a and sleeve (slip-
fitter) 6b which fits over the top portion of the pole. Surrounding
pole 1 is luminaire support ring 2 having secured thereto a number of
luminaires 3 uniformly spaced around the support ring. A plurality of
hoisting cables 4 (typically three) secured to support ring 2 pass over
correspondingly arranged pairs of sheaves 5 (see Figure 2) mounted on
head plate 6 and extend downwardly through the interior of the pole to
suitable motorized winch apparatus at the bottom of the pole (not shown),
which is operable for raising and lowering luminaire support ring 2 by
winding and unwinding cables 4. Support ring 2 is held in its uppermost
l~O9Q43
(operative) position by a plurality of latches 7 mounted on ring 2 to
which the hoist cables 4 are respective~Ly at-tached and which engage
latch locking devices ~ correspondingly arranged on head plate 6. The
latching apparatus and i-ts operation are more fully disclosed in related
Canadian application Serial No. ~ / ~ ,7 q O filed
o~t~ 5, 19 ~ ~ and assigned -to the same assignee as
the present invention.
Power cable 9, connected at one end to wiring box 10
secured to support ring 2 for transmitting current to luminaires 3, passes
around power cable sheave 15 and downward -through pole 1 for connection
to a power source (not shown) near the bot-tom of the pole.
In accordance with the present invention, apparatus is
provided for maintaining support ring 2 centered on the pole, expecially
during its movement between its upper (operative) position and its
lower (service) position, so as to avoid undesirable interference of
support ring 2 and associated parts with pole 1, such as may be caused
by winds, warping of the pole, or other conditions. The centering
apparatus in the illustrated embodiment, as seen in Figures 2 and 3,
comprises three generally U-shaped guide members 12 each formed with a
central portion 12a on which elongated roller 11 is rotatably mounted.
Arms 12b of member 12 extend in devergent directions from the central
portion and have opposite end portions or shafts 12c extending outwardly
at an angle thereto so as to define an axis parallel to the axis of
central portion 12a about which roller 11 rotates. Arm end portions ~ -
12c are pivotally secured to support ring 2 by suitable brackets or the
like for pivoting about their above-mentioned axis, and coil springs 13
are arranged thereon so as to constantly urge rollers 11 toward the axis
of support ring 2 and into contact with the adjacent (proximate) surface
of pole 1. As will be seen, the dimensions of guide members 12 are such
that the maximun radial extension thereof toward the axis of support
ring 2 is less than the radius of the support ring. Under usual conditions,
the axis of roller 11 is lower than the pivot axis of the outer ends of
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guide member 12. As support ring 2 is lowered on pole 1, guide
members 12 pivot do~nwardly and rollers 11 move farther away from
the plane of suppor-t ring 2 as the diameter of the pole increases.
Since each guide member 12 pivots about a chord of a circle whose
center is at the axis of support ring 2, roller 11 is always held
tangent to the pole in a position subs-tantially perpendicular to a
radius of support ring 2 which substantially bisects roller 11. By
virtue of the spring-biased roller arrangement shown, rollers 11 main-
tain a force tending to restore support ring 2 to a centered posi-tion
substantially coaxial with the pole and serve as a shock absorbing
means to avoid shock -to the luminaires mounted on ring 2.
In a preferred embodiment of the invention, means are
provided for limiting the extremes of movement of guide members 12.
As seen in Figures 5 and 6, shafts 12c at the opposite ends of guide
members 12, which pivot in support brackets 15, are provided with pins
16 projecting through the shaft normal to its axis, as seen best in
Figure 6. Stops 17 and 1~, one of which may be constituted by the
projecting end of coil spring 13, are provided on bracket 15 which are
engageable by pin 16 to limit the range of pivotal movement of guide
members 12. Shown in Figure 6 are three different positions A, B and
C of guide member 12. When support ring 2 is forced off-center by winds,
for example, so as to cause one roller 11 to move downwardly against the
pole, the remaining rollers 11 are kept from riding upwardly on the
pole to a level as high as the horizontal plane containing the pivot
axis of the support ring 2, as illustrated by position A of guide member
12 in support ring 2, as illustrated by position A of guide member 12
in Figure 6, wherein pin 16 strikes stop 17 to prevent further inward
pivoting of guide member 12. In this way, rollers 11 are maintained
in the proper position not only for keeping the support ring centered
on the pole, but also for facilitating installation of the support ring
on the pole.
The extreme outward movement of guide member 12 is limited
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to a position wherein the guide member does not extend beyond the
circumference of suppor-t ring 2, so as to always space ring 2 from
the pole and -thereby avoid marring or damaging the pole surface by
contact wi-th the suppor-t ring, especially during the raising or
lowering procesure, and also to prevent shock to the luminaires and
their components by such contact.
Position B of guide member 12 represents an intermediate
position between the inward and outward extremes of pivotal moYement
of guide member 12, with pin 16 free to moye between stops 17 and lg.
~igure 4 illustrates a modification of the above-described
device, wherein guide members 12 are interconnected at their outer ends
by gears 14 so that the guide members are forced to act in concert,
Thus, when support ring 2 moves off-center causing one roller 11 to
move downwardly away from support ring 2 in contact with pole 1, the
other two rollers 11 similarly move downwardly but will not be in con~
tact with the pole, The advantage of this arrangement is that the other
two rollers will not exert any force on the pole which must be overcome
by the one roller in re-centering the support ring, Also~ since the
rollers always move in the same direction to the same degree~ an~ prob~
2a lems which might result from the rollers moving in opposite directions
relative to the support ring are avoided~
As will be understood~ other means of interConnec~ing
members 12-may be employed if desired,
While the present invention has been described with reference
to particular embodiments thereof, it will be understood that numerous
modifications may be made by those skilled in the arb without actually
departing from the scope of the invention. Therefore, the appended claims
are intended to cover all such equivalent variations as come within the
true spirit and scope of the invention.
