US 3400905 A
Description (OCR text may contain errors)
P 1963 H. A. VAN DUSEN, JR 3,400,905
SUPPORT POLE ASSEMBLY FOR ELECTRICAL APPARATUS Filed Oct. 5, 1966 2 Sheets-Sheet 1 INVENTOR. izczrola 7 477 Dusen A BY 3 4, Wm
fittarmgy P 196 8 H. A. VAN DUSEN, JR 3,400,905
SUPPORT POLE ASSEMBLY FOR ELECTRICAL APPARATUS Filed Oct. 5. 1966 g sheets-Sheet 2 IN VEN TOR.
United States Patent 3,400,905 SUPPORT POLE ASSEMBLY FOR ELECTRICAL APPARATUS Harold A. Van Dusen, Jr., South Milwaukee, Wis., as-
siguor to McGraw-Edison Company, Milwaukee, Wis.,
a corporation of Delaware Filed Oct. 5, 1966, Ser. No. 584,403 3 Claims. (Cl. 248-44) ABSTRACT OF THE DISCLOSURE A pole supporting assembly for attaching a pole to a base structure including a base member with an interior frustoconical surface into Which the lower end of the pole is inserted. The assembly further includes a plurality of wedge-like collets which are forcefully inserted between the interior surface of the base member and the lower exterior surface of the pole. The assembly further includes rim means, or inwardly projecting means, for supportingly engaging the lower end of the pole.
In general terms, the invention comprises an assembly for supporting electrical apparatus, including an elongate pole shaft, an anchor base having internal surface means displaced from and disposed in surrounding relation to one end of the pole shaft, and being at least partially inclined relative to the pole axis, and a plurality of collet members disposed between the surface means and the pole, each of the collet members having an inclined outer face portion complementary with the inclined surface for being moved into high pressure engagement therewith and also including an inner pole gripping means for being moved into high pressure resilient engagement with the pole. The assembly further comprises rim means or inwardly extending means for supportingly engaging the lower end of the pole.
It is the general practice in the installation of poles for roadway luminaires to weld the pole shaft to an anchor base. This required the stocking of various sized anchor bases for different pole sizes and lengths. In addition welding required that the pole be assembled to the base before transportation to the field which generally increased shipping costs, introduced relatively long delays and in addition prevented field repair.
It is an object of the invention to provide a pole assembly for supporting roadway l-uminaires wherein a single anchor base may accommodate various pole shaft sizes and gauges.
Another object of the invention is to provide a luminaire support pole assembly wherein the pole shaft is not welded to the anchor base.
Another object of the invention is to provide a luminaire wherein the pole shaft may be field assembled to the anchor base and damaged components may be field repaired.
A further object of the invention is to provide an assembly for mechanically coupling a pole to an anchor base wherein the pole and base are prestressed to minimize deflection in said pole as the result of loading at its upper end.
These and other objects and advantages of the instant invention will become more apparent from the detailed description thereof taken with the accompanying drawings in which:
FIG. 1 is a side elevational view of a luminaire support pole incorporating the instant invention;
FIG. 2 is a fragmentary view of the pole illustrated in FIG. 1 which shows the anchor base and pole shaft cou- P FIG. 3 is a view taken along lines 3-3 of FIG. 2; and
3,400,905 Patented Sept. 10, 1968 FIG. 4 shows one of the collet members of the assembly.
Referring now to the drawings in greater detail FIG. 1 shows a vertical support pole assembly 10 which supports a roadway luminaire 11 in its upper end and includes an anchor base assembly 12 and a pole shaft 13. The anchor base 12 may be affixed to a concrete pad 14 by elongate anchor bolts 15.
The anchor base 12 is shown in FIGS. 2 and 3 to include a metallic base member 18 and a plurality of collet members 19 Which are releasably securable to the base member 18 and which embrace the lower end of the pole shaft 13.
The base member 18 includes an outer annular flange 21 having a plurality of spaced holes 22 for receiving the upper ends of the anchor bolts 15 which are secured by nuts 23. The base also includes an annular, generally frusto-conical shell portion 25 integral with the flange 21 and extending upwardly therefrom. The upper end of the shell portion 25 is provided with a central aperture 26 for receiving the pole shaft 13. The internal surface 27 of the shell portion 25 provides a generally conical hearing surface for the collet members 19.
In addition a plurality of spaced, downwardly facing bosses 30 are formed on the surface 27 and each has a threaded hole 32 formed through its lower surface for receiving one of a plurality of bolts .33 each of which secures one of the collet members 19 to the base member 18.
The collet members 19 are shown in FIGS. 2-4 to include a plurality of rib portions 38 for embracing the pole 13, a base portion 40 for supporting the pole 13 and a back face portion 42 for engaging the bearing surface 27 and for supporting the rib portions 38 and the base portion 40.
The back face portion 42 of each of the collet members 19 extends the full height of the member and in section has a generally U-shaped central part 44 and a pair of arcuate side parts 45. The rear surface 46 of each of the side parts is a section of a conoid which is complementary to and disposed in the engagement with the bearing surface 27. The rib portions 38 are integral with and extend in generally parallel planes transverse to the back portions 42. In addition each rib portion 38 comprises an arcuate segment which terminates in an arcuate front surface for engaging the pole 13. The base portion 40 is generally conical and has a central aperture 48 for receiv ing the bolt 33 and an inner edge 50 which extends inward inwardly beyond the surfaces 47 on ribs 38 for engaging the underside of pole 13.
In assembly of the anchor base 12 to the pole 13 a plurality of collet members 19, preferably three or more, are loosely secured within the base member 18 by bolts 33. The pole 13 is supported in a horizontal position and the anchor base 12 is then slid over the end of the pole shaft until the lower end of the pole engages the base portions 40 of the collet members 19. Each of the bolts 33 is then tightened until the collets are snugly in place and the bottom edges lie in substantially the same plane. Each of the collet members 19 are then hammered so that they are driven between the bearing surface 27 and the pole 13 and then retightened. This process is repeated until the desired degree of contact pressure between the collet members 19 and the bearing surface on the pole are achieved.
When the bolts 33 are first tightened to move the collet members 19 into position, the latter will bear against the pole 13 and the surface 27 only at a few localized high spots due to inevitable tolerance differences in their contours. After the collet members 19 have initially been drawn into place by the moderate force that the bolts 33 are able to exert, substantial further motion occurs when high impact forces are applied as the result of hammering. Forcing the collet members 19 into place under high pressure will create localized bending loads in the pole 13 and the shell portion 25 adjacent to the localized contact points between those areas and the members 19. These localized bending loads will cause the pole 13 and the shell portion 25 to deform until they substantially match the contour of the collet members 19.
After the engaged portions of the pole 13 and the shell portion 25 are in substantial distributed engagement with the collet members 19, further motion of the latter will be substantially resisted. The additional insert forces will then result in almost pure circumferential compressive stress in pole 13 and circumferential tensile stress in shell portion 25. Additional deformation in these components due to pure tensile stress loads without additional bending will be minute.
In service, the pole 13 acts in a manner similar to a cantilever beam attached to its foundation by means of the base assembly 12. The normal in-service loads applied to the pole 13 result in stresses in the pole and the base member 18 which are quite similar to the stresses resulting when the collet members 19 are driven into place. However, because of the initial deformation and prestressing which occurs during the high pressure insertion of the collet members 19, undesirable deflection at the upper end of the pole 13 as a result of deformation in the base member 18 and the lower end of the pole 13 will be minimized.
The purpose of the rib portions 38 on the collet members 19 is to provide a bearing area with the pole 13 over a widely distributed area. However, it is not necessary that the members 19 bear over their entire areas against the pole 13. For this reason it is possible to employ the rib portions 38 on the collet members 19 rather than a more expensive solid member. It has been found that adequate bearing area can be obtained if the height of the collet members 19 is at least substantially equal to the diameter of the pole 13 at its lower end, although this is by no means intended to be limiting.
It can be seen that the anchor base assembly 12 according to the instant invention can be assembled to the pole 13 without welding and without the necessity for close tolerances therebetween. In addition the anchor base assembly 12 can be assembled to the pole 13 regardless of the thickness gauge of the two members. In addition broken or damaged anchor base assemblies 12 or poles 13 may be field replaced.
While only one embodiment of the instant invention has been shown and described, it is not intended that the invention should be limited thereto but only by the scope of the appended claims.
1. In an assembly for supporting electrical apparatus, the combination of:
an elongate pole shaft having a longitudinal axis and an outer surface means adjacent its lower end;
an anchor base having internal surface means displaced from and disposed in surrounding relation to said outer surface means on said pole shaft, said anchor base including a hollow shell portion which is open at its upper end for receiving said pole shaft and wherein said internal surface means is inclined toward said pole from its lower end to its upper end; and
a plurality of collet members disposed between said surface means, each of said collet members having inner and outer face portions which are substantially complementary to said surface means for being moved into high pressure frictional engagement therebetween to locally deform and prestress said base and said pole shaft to minimize deflection in said pole as a result of loading at the upper end thereof, the lower end of said anchor base also being open for receiving said collet members; and
said collet members each including a base portion extending inwardly beyond the surface of said pole shaft for supportingly engaging the lower end thereof.
2. The assembly set forth in claim-1 wherein the outer face portion of each of said collet members includes an elongate slot extending in a direction generally parallel to said axis, a plurality of boss means formed on said inner surface means for receiving said slots, and bolt means extending between the base portion of each of said collet members and one of said boss means and along said slots for moving said collet members into said high pressure engagement between said surface and said pole.
3. The assembly set forth in claim 1 wherein at least a portion of said inner surface means is generally a conical section.
References Cited UNITED STATES PATENTS 2,784,015 3/1957 Swanson 2871 19 2,937,038 5/1960 Gondek 28752.06 X 3,279,870 10/1966 Janiszewski 28720.3 X
FOREIGN PATENTS 2,823 4/ 1919 Netherlands.
ROY D. FRAZIER, Primary Examiner.
FRANK DOMOTOR, Assistant Examiner.