Mast support assembly

A support assembly for a mast includes a mounting plate to which a cradle can be permanently fused or attached by means of spacers of different thickness to select the desired spacing of the mast from the mounting plate. The cradle has an arcuate mast support surface which extends axially to a length at least twice the arcuate length. The arcuate arc length is preferably less than 180.degree.. The mounting plate is adapted to be secured to a masonry wall, such as the side of chimney, by means of masonry screws or the like. To this end the mounting plate is provided with at least two mounting holes, at least one of which is elongated to assure that both mounting holes overlie mortar spaces between bricks in the masonry wall. The supported mast is clamped to the cradle by means of a U-bolt and toothed bracket plate. In the preferred embodiment, two such assemblies are secured to the wall with their mast support surfaces in axial alignment.

BACKGROUND OF THE INVENTION 
1. Technical Field 
The present invention relates to mast support assemblies and, more 
particularly, to mast support assemblies which are particularly suited for 
securing television antenna masts to masonry walls and chimneys. 
2. The Prior Art 
Optimum reception of television signals at a given location is achieved 
when the antenna is secured to the highest structure at that location. For 
most homes, the highest structural portion is a chimney which very often 
is made of brick and mortar. The conventional technique for securing a 
television antenna mast to a masonry chimney is by means of cables wrapped 
about the chimney. An example of this technique is illustrated in U.S. 
Pat. No. 3,208,703 to Arnold et al. This cable-wrapping approach has a 
number of associated disadvantages. For example, when the chimney 
periphery is large, installation requires more than one person. In other 
words, a single person can not reach around the chimney periphery to wrap 
the cable and secure the mast. In addition, the cable tension changes with 
temperature so that the force holding the antenna mast against the chimney 
occasionally loosens and moves with the wind. This produces interference 
in the received television signal as well as introducing the danger of the 
entire antenna coming loose and falling from the chimney. Further, the 
upper lip of many chimneys projects horizontally outward beyond the main 
chimney periphery, thereby requiring a make-shift spacer to be installed 
between the chimney and antenna mast so that the mast can clear the 
projecting lip. This severely impairs the integrity of the cable-wrap 
mounting arrangement and further complicates the installation process. 
In attempting to solve the aforesaid problems, I discovered additional 
areas of concern. For example, in attempting to secure an antenna mast 
directly to a masonry chimney with a bracket and masonry screws, or the 
like, I noted that the structural integrity of the mounting arrangement 
was poor. Moreover, the bracket mounting holes did not always align with 
mortar spaces between the bricks and the chimney wall, thereby requiring 
the creation of additional mounting holes. Further, the spacing of the 
antenna mast to clear the lip of the chimney is not completely solved 
merely by spacing a mounting bracket from the chimney wall. Specifically, 
it is desirable, on the one hand, to clear the chimney lip; but it is also 
desirable to keep the mast as close to the chimney as possible to take 
advantage of the chimney structural support and to minimize the torque 
load created by the weight of the mast on the extended bracket and spacer. 
OBJECTS AND SUMMARY OF THE INVENTION 
It is therefore a primary object of the present invention to provide a 
mounting arrangement for a television antenna mast which permits the mast 
to be simply and securely mounted on a masonry chimney as close to the 
chimney as possible while clearing the upper lip of the chimney. 
It is another object of the present invention to provide a mast mounting 
arrangement which can be easily secured to any masonry chimney regardless 
of the size of the chimney and the size and spacing between bricks in the 
chimney wall. 
Still another object of the present invention is to provide a mast mounting 
assembly which permits a mast to be mounted on a structural wall in 
substantially any orientation in a plane parallel to the wall. 
A further object of the present invention is to provide a mast mounting 
assembly which is simple to install and which securely supports the mast 
against wind forces. 
In accordance with the present invention, a mast mounting assembly includes 
a mounting plate and cradle. The mounting plate has a flat rear surface 
adapted to abut a structural wall to which the plate is secured by screws, 
or the like, extending through mounting holes in the plate. At least one 
of the mounting holes is an elongated slot which permits the mounting 
holes to be positioned in alignment with mortar spaces between bricks when 
the structural wall is a masonry wall. The cradle has a mast support 
surface which faces away from the mounting plate and which is elongated in 
the direction of the supported mast with an arcuate cross-section. The 
axial length of the mast support surface is considerably larger than the 
arcuate cross-section length. In the preferred embodiment the 
cross-sectional length subtends an arc which is less than 180.degree. but 
greater than 120.degree.. The supported mast is clamped in the cradle 
along the mast support surface by a U-bolt to which a tooth bracket member 
is secured against the mast. 
In one embodiment the cradle is welded, braised or otherwise permanently 
fused to the front surface of the mounting plate so that the entire unit 
is integral or inseparable. The fused portion is in the form of a bridge 
or neck which extends the cradle transversely away from the mounting plate 
so that a supported mast can clear the projecting upper lip of a chimney 
to which the mounting plate is secured. 
In another embodiment the mounting plate and cradle are separate units 
which are interconnected by a spacer. The particular space is selected by 
its width dimension in accordance with the spacing required to permit the 
mast to clear the chimney lip or other overhanging projection. Aligned 
screw holes in the mounting plate, spacer and cradle permit the three 
elements to be easily secured together by a screw and nut arrangement. The 
cradle is preferably in the form of a longitudinally-truncated pipe 
section and the spacer includes an arcuate recess within which the pipe 
section is received. By rotating the spacer about its screw hole with 
respect to the mounting plate, the arcuate recess and cradle can be 
secured at various angles in a plane parallel to the mounting plate and 
the structural wall. 
In the preferred embodiment two assemblies are employed to support the 
mast, the assemblies being oriented with their mast support surfaces in 
axial or longitudinal alignment. 
It should be stressed that, while the embodiments of the invention 
described herein are oriented toward supporting a television antenna mast 
on a masonry wall or chimney, the principles of the present invention are 
applicable to supporting any mast on substantially any structural wall or 
surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring specifically to FIGS. 1-6 of the accompanying drawings in greater 
detail, a conventional masonry chimney 10, made of multiple bricks 11 
spaced by mortar 13, serves as a structure on which a television antenna 
mast 15 is to be mounted. The chimney has an overhang or lip 17 projecting 
transversely outward from its top. 
A mounting unit for mast 15 includes a mounting plate 20, a cradle member 
30 and a spacer element 40. The mast 15 is secured to cradle member 30 by 
means of a U-bolt 50 and toothed bracket member 51. Mounting plate 20 is a 
flat, generally rectangular, elongated plate having two 
longitudinally-spaced mounting slots 21 and 22 defined therethrough and 
extending longitudinally along the length dimension of the plate. Slots 21 
and 22 serve as mounting holes by which the mounting plate 20 can be 
secured to the chimney 10 by mounting screws, or the like. In the 
illustrated embodiment, the means for securing the mounting plate to the 
chimney includes a pair of radially-expandable screw retaining members 23 
which are inserted into respective bores formed in respective mortar 
portions 13 of the chimney at the time of installation. Screw retaining 
members 23 receive respective screws 24 which are inserted through slots 
21, 22 and tightened to receive mounting plate 20 with its flat rear 
surface flush against the chimney. The peripheral configuration of 
mounting plate 20 is not of crucial importance, although as a practical 
matter it is desirable that the plate be as small and lightweight as 
possible. However, at least one of the mounting holes 21, 22 must be an 
elongated slot which is longitudinally aligned with the other mounting 
hole which may be a small round hole large enough only to receive screw 
24. The purpose of having at least one elongated slotted mounting hole is 
to assure that the mounting plate can be positioned on the chimney such 
that both mounting holes overlie a mortar section 13. One or more cradle 
mounting holes 25 are defined through mounting plate 20, preferably at a 
location intermediate two mounting slots 21, 22. Holes 25 are countersunk 
at the rear surface of mounting plate 20 to receive a nut 26 which engages 
a screw 27 used to secure the cradle 30 and spacer 40 to the mounting 
plate 20. 
Cradle member 30 takes the form of a longitudinally-truncated pipe section 
having a concave mast support 31 and a convex rear surface 33. A mounting 
hole 35 is defined through the cradle member and is preferably countersunk 
at mast support surface 31 to receive the head of screw 27. Mast support 
surface 31, by virtue of its concavity, has an arcuate cross-section which 
subtends an arc that is less than 180.degree.. In the preferred embodiment 
of the invention this arc is greater than 120.degree.. The importance of 
these arcuate length limitations will become apparent from the description 
set forth below with respect to FIGS. 7 and 8. In addition, the axial 
length of the mast support surface 31 must be considerably greater than 
the arcuate length of its cross-section. This feature is required to 
provide firm contact support for mast 15 along an extended portion of the 
mast length. In this regard it is important that the axial length of 
surface 31 be at least twice, and preferably four to eight times, the 
arcuate length. 
The radius of curvature of mast support surface 31 is selected to match the 
radius of the outer wall of a typical antenna mast, as best illustrated in 
FIG. 6. This provides maximum surface contact between the support surface 
31 and and antenna mast 15 along the arcuate length of the support 
surface. In a typical embodiment, this radius is 11/16 inch. The axial 
length of surface 31 is typically six inches. 
Spacer element 40 has a flat rear surface 41 (as best seen in FIG. 5) and 
an arcuate front surface 43 (as best seen in FIG. 2). Flat rear surface 41 
is placed flush against the forward surface of mounting plate 20. The 
concave front surface 43 is arcuately contoured to match and receive the 
convex rear surface 33 of cradle member 30. The axial and arcuate lengths 
of spacer front surface 43 can be less than the corresponding dimensions 
of the abutting rear surface 33 of cradle member 30. A mounting hole 45 is 
defined through spacer 40 from front to back to permit screw 27 to pass 
therethrough when the cradle 30, spacer 40 and mounting plate 20 are 
secured together. 
The thickness of spacer 40 between its rear surface 41 and front surface 43 
determines the transverse spacing of cradle 30 and mast 15 from chimney 
10. In this respect, additional interchangeable spacer elements 40' and 
40" (see FIG. 2) of different thicknesses may be provided to properly 
space the mast 15 from the chimney for different projecting widths of 
overhang lip 17. Spacer elements 40, 40' and 40" are identical in all 
respects except for the thickness dimension. Typically, the thickness of 
spacers 40, 40' and 40" may be one inch, one and one-half inch, and 
one-half inch, respectively. Of course, other thickness dimensions may be 
employed. 
The U-bolt 50 is generally placed with its arcuate base portion surrounding 
the rear surface 33 of cradle member 30 and its legs projecting forwardly 
of the cradle member. Bracket plate 51 has two parallel planar sections 
with arcuately-recessed portions in which pointed teeth 52 are defined. A 
connection section of the bracket plate perpendicularly joins the two 
parallel sections and is provided with two through holes 53 and 54. In 
securing the mast 15 to cradle member 30 along mast support surface 31, 
bracket 51 is slipped onto the U-bolt with the legs of the U-bolt 
extending through bracket hole 53, 54 and with teeth 52 facing mast 15. 
The legs of the U-bolt are threaded to receive nuts 55, which may be wing 
nuts, which are then tightened to force teeth 52 against the mast to hold 
the mast securely in the cradle. 
Although a single mounting unit may be sufficient to securely mount the 
antenna mast 15 to chimney 10 in many cases due to the axially elongated 
support surface 31, it should be noted that two axially aligned units, as 
shown in FIG. 1, provide even greater security for all installations. 
Referring to FIGS. 7 and 8, it should be noted that the present invention 
permits a secure mounting of a mast even if the outside curvature of the 
mast does not conform precisely to the curvature of support surface 31. An 
undersize mast, as seen in FIG. 7, for example, is urged against the 
arcuate mast support surface 31 by bracket plate 51 which holds the mast 
securely in place within the cradle. Likewise, for an oversize mast such 
as illustrated in FIG. 8, the mast is contacted by both longitudinally 
extending edges of surface 31 and is held in place by bracket plate 51. 
Although the broad arcuate area contact with the mast is not present for 
oversize and undersize masts, the axially elongated cradle provides 
contact along relatively long segments of the mast to assure proper 
mounting support. 
As illustrated in FIG. 4, and as briefly described above, by rotating 
spacer 40 relative to mounting bracket 20, it is possible to change the 
angular orientation of the mast relative to mounting plate 20. In FIG. 4 
the cradle is shown oriented perpendicular to the length dimension of the 
mounting plate but it will be appreciated that any angular orientation can 
be obtained. 
An alternative embodiment of the invention is illustrated in FIG. 9 wherein 
the cradle 30 and mounting plate 20 are joined by a spacer 60 and all 
three elements are fused together by welding, brazing, or the like. The 
resulting integral structure lacks the flexibility of positioning the 
cradle, both angularly and in its spacing from the mounting plate. 
However, for some applications this lack of flexibility may be acceptable 
and more convenient. Cradle 30 is shown in FIG. 9 to be fixed 
perpendicular to the length dimension of mounting plate 20 but it may be 
fixed in any angular orientation. 
Having described several embodiments of a new and improved mast mounting 
arrangement constructed according to the present invention, it is believed 
that other modifications, variations and changes will be suggested to 
those skilled in the art in the light of the above teachings. It is 
therefore to be understood that all such variations, modifications and 
changes are believed to fall within the scope of the invention as defined 
by the appended claims.