Roof bow locking system

A locking arrangement for securing roof bow members of a trailer unit wherein several bow members are mounted at one side wall of the trailer for vertical pivoting and are simultaneously latched at an opposing side wall to prevent vertical movement thereof. The latching mechanism consists of a plurality of locking bar levers which are each pivoted on the opposing side wall to have one end overlie a retaining ring on one end of the bow members. A common actuator rests on top of the opposing wall and is pivotally attached to each of the locking bar levers at their non-overlying end. A shaft is connected by a pivot arm to the actuator and extends vertically downward adjacent the floor of the trailer where it is attached to a pivot handle to cause the locking bar levers to be positioned in either an overlying or non-overlying position with respect to their individual retaining rings.

BACKGROUND AND SUMMARY OF THE INVENTION 
The present invention relates to a roof bow system for a trailer unit. More 
particularly, the present invention relates to a roof bow system in which 
one end of each individual roof bow is held in a support member and is 
locked in the support member by individual locking devices, with all of 
the locking devices actuated by a common actuation device. 
Conventional roof bow systems for open-top trailer units are known. Such 
roof bow systems are used on open trailer units of conventional 
tractor-trailer assemblies to support a flexible cover which is normally 
placed over the top of the trailer unit. Such conventional roof bow 
systems include a plurality of individual roof bow members which are 
generally bars which extend laterally across the top of the trailer unit 
from side to the other. Each roof bow member includes a downwardly turned 
end which is sized and oriented to engage a recess formed in the top rail 
of each side of the trailer unit. Each roof bow member may be angled 
somewhat near its center such that, when installed, the roof bow member 
has somewhat domed shape. 
The recesses formed in the top rails of the sides of the trailer are 
normally simply downwardly extending holes in that top rail. The recesses 
are sized such that the corresponding end of the roof bow member exactly 
fits within the recess with little or not play permitted. This provides 
for a tight fit of the roof bow ends in the recesses which is necessary so 
that the roof bow members are not subject to excess movement or vibration 
when the trailer is moving. 
One problem with conventional roof bow systems utilizing the 
above-described tight fit of the roof bow members in the individual 
recesses is that, because of the tight fit, the roof bow members are 
difficult to remove from the recesses when desired. It will be understood 
that it is necessary to remove the roof bows when unlimited access to the 
trailer unit is necessary. For example, whenever it is necessary to drive 
a conventional forklift into the trailer unit to either load or unload the 
trailer, the roof bow members must be removed, or at least one end of each 
roof bow must be removed from the corresponding recess so that the roof 
bow member can then be pivoted out of the way. The difficulty in removing 
the roof bow members from the recesses is further aggravated whenever the 
roof bow members become bent or misshapen in any way. It is often 
necessary to strike the underside of the roof bow member with a large 
hammer or the like in order to remove the end of the roof bow member from 
the associated recess. By striking the roof bow member with sufficient 
force to dislodge it, the problem of bending or otherwise damaging the 
roof bow members is accentuated. 
It is therefore one object of the present invention to provide a roof bow 
system for a trailer unit in which one end of each individual roof bow is 
captured in a support member and is easily removed from the support member 
when desired. 
Yet another object of the present invention is to provide a roof bow system 
for a trailer unit in which a locking device is provided to capture one 
end of each individual roof bow member in a corresponding support member, 
with all of the locking devices movable between a locked position and an 
unlocked position. 
Yet another object of the present invention is to provide a roof bow system 
for a trailer unit in which all of the locking devices are moved 
simultaneously between the locked position and the unlocked position by a 
common actuation device. 
According to the present invention, a roof bow system for a trailer unit 
for supporting a cover for the trailer unit is provided. The trailer unit 
has spaced-apart, generally parallel upstanding first and second walls. 
The roof bow system includes a plurality of bow members, each having a 
first end and a second end and each extendable between the first wall and 
the second wall of the trailer to support the cover. The system also 
includes means for mounting the first end of each of the roof bow members 
to the first wall of the trailer for pivotal movement. Means for loosely 
supporting the second end of each of the bow members on the second wall is 
provided such that each bow member extends between the first wall and the 
second wall to support the cover. Means for locking the second end of each 
of the bow members in the supporting means and means for actuating each 
locking means such that the second end of each bow member is locked and 
unlocked substantially simultaneously are provided. 
One feature of the foregoing structure is that means for loosely supporting 
the second end of each of the bow members to the second wall is provided. 
One advantage of this feature is that the supporting means only loosely 
supports each of the bow members in a preliminary orientation which 
permits easy insertion and withdrawal of the bow member into the support 
means when desired. 
Another feature of the foregoing structure is that means for locking the 
second end of each of the bow members securely in the supporting means is 
provided. One advantage of this feature is that, once the second end of 
the bow member is placed in the supporting means, the locking means can be 
actuated to secure the bow member in the supporting means. 
Yet another feature of the foregoing structure is that means for actuating 
each of the locking means such that the second end of each bow member is 
locked and unlocked substantially simultaneously as provided. One 
advantage of this feature is that, upon actuation of the actuating means, 
all of the locking means are either locked or unlocked simultaneously to 
permit rapid assembly and disassembly of the roof bow system. 
Additional objects, features, and advantages of the invention will become 
apparent to those skilled in the art upon consideration of the following 
detailed description of a preferred embodiment exemplifying the best mode 
of carrying out the invention as presently perceived.

DETAILED DESCRIPTION OF THE DRAWINGS 
Referring now to the drawings, FIG. 1 illustrates a portion of a 
conventional trailer unit 10 that is part of a conventional truck 
tractor-trailer assembly. The trailer 10 includes a first side wall 12 and 
an opposite, second side wall 14 and is open on top. The first side wall 
12 includes a first upper rail 16 and the second side wall 14 includes a 
second upper rail 18. A plurality of roof bow members 20 (two of which are 
shown in FIG. 1) are provided that extend between the first upper rail 16 
and a second upper rail 18. The roof bow members 20 are provided to 
support a flexible cover 24 such as a tarpaulin or the like which is 
provided to cover the open top of the trailer 10. Although the entire 
trailer 10 is not shown, the trailer 10 is a conventional trailer unit 
which has a conventional length of approximately 45 feet. The roof bow 
members 20 are spaced-apart a conventional distance, approximately two 
feet in the illustrated embodiment. Thus, in such a forty-five foot 
trailer, there will be approximately twenty to twenty-five roof bow 
members 20. 
Each roof bow member 20 has a first end 26 and an opposite, second end 28. 
The first end 26 of each bow member 20 is mounted in the first upper rail 
16 for pivotal movement about a vertical axis. Although not shown in 
detail, the first end 26 of each bow member 20 fits into a recess formed 
in the first upper rail 16 to define the pivot axis. The recess (shown in 
dotted line in FIG. 1) into which the first end 26 is inserted is a 
conventional recess such as used on most conventional open trailers to 
receive the ends of roof bow members. Thus, the first upper rail 16 is 
unmodified in the trailer unit 10. The first end 26 fits into the recess 
in the first upper rail 16 such that pivotal movement of the roof bow 20 
about the first end 26 is permitted. 
A locking assembly 30 is provided for securing the second end 28 of each 
roof bow member 20 to the second upper rail 18. The locking assembly 30 is 
mounted on the second side wall 14 of the trailer 10. Specifically, the 
locking assembly 30 is mounted on the second upper rail 18, with a portion 
of the locking assembly 30 mounted on the vertical second side 14. The 
locking assembly 30 is provided to easily attach the second end 28 of each 
roof bow member 20 to the second upper rail 18. Specifically, the locking 
assembly 30 permits the second end 28 of each roof bow member 20 to be 
easily locked in the proper position on the second upper rail 18 so that 
the roof bow member 20 is properly positioned to support the cover 24. In 
addition, the locking assembly 30 permits the second end 28 to be easily 
unlocked such that the second end 28 of the roof bow member 20 is 
disengaged from the second upper rail 18. This permits the roof bow member 
20 to be pivoted about the first end 26 toward the first side 12 to permit 
easy access into the interior of the trailer unit 10. Specifically, when 
unlocked, each roof bow member 20 can be pivoted to a storage position 
(not shown) where it is substantially flush and aligned with the first 
side 12 of the trailer 10. 
FIG. 2 illustrates in greater detail the locking assembly 30 of the present 
invention. Specifically, the locking assembly 30 includes a support 
receptacle 36 that is attached to the inside surface of the second upper 
rail 18. It will be understood that one receptacle 36 is provided for each 
roof bow member 20. However, the following discussion will be directed to 
only that portion of the locking assembly 30 corresponding to one roof bow 
member 20. Each receptacle 36 is sized and configured to receive the 
second end 28 of the roof bow member 20 in a loosely held orientation. 
The second end 28 of the roof bow member 20 is modified by the addition of 
a retaining ring 38 which is welded or otherwise attached to the 
downwardly turned second end 28. It will be understood that the addition 
of the retaining ring 38 is the only modification necessary to otherwise 
conventional roof bow members 20 so that they are adapted for use with the 
locking assembly 30 of the present invention. In all other aspects, the 
roof bow member 20 is a conventional unit. 
A pivoting locking bar 42 is provided that is pivotally mounted on the 
second upper rail 18 and pivots on a pivot bolt 48. The locking bar 42 
includes a locking portion 44 which extends over the receptacle 36 when in 
a locked position (FIG. 3), and an opposite drive end 46 that is attached 
to an elongated linkage bar 52 for a movement therewith. The linkage bar 
52 is attached to each of the plurality of locking bars 42. Thus, 
simultaneous pivotal movement of each locking bar 42 is achieved by 
movement of the common linkage bar 52. 
A rotating actuation rod 54 extends vertically downwardly through the 
second upper rail 18 and is connected to the linkage bar 52 by an arm 56. 
Brackets 58 are mounted on the inside of the second side wall 14 of the 
trailer 10 to permit rotational movement of the actuation rod 54. A handle 
60 is affixed to the actuation rod 54 to provide the leverage necessary to 
rotate the actuation rod 54. A handle lock 62 is mounted on the inside of 
the second side wall 14 and serves to receive the end of the handle 60 to 
lock the actuation rod 54 after it has been rotated fully in the direction 
of arrow 64 toward the second side wall 14. 
It will be understood from FIG. 2 that, when handle 60 is rotated in the 
direction of arrow 64, the linkage bar 52 will move in the direction of 
arrow 65. When linkage bar 52 is moved in the direction of arrow 65, the 
locking portion 44 of the locking bar 42 is pivoted toward the 
corresponding receptacle 36. This pivoting movement of the locking portion 
44 of the locking bar 42 will act to capture the second end 28 of the bow 
member 20 within the receptacle 36 in such a manner that the second end 28 
is rigidly secured within the receptacle 36. When in this position, the 
roof bow 20 is rigidly maintained in a proper position for supporting the 
cover 24. Likewise, rotation of the handle 60 in the direction opposite 
the arrow 64 will rotate the locking bar 42 to the unlocked position away 
from the receptacle 36. 
FIG. 3 shows in greater detail the positioning of the locking bar 42 to 
secure the second end 28 of the bow member 20 in the receptacle 36. Each 
receptacle 36 includes an upstanding wall portion 66 with one portion 67 
of the upstanding wall 66 facing the forward portion of the trailer 10, 
and a second portion 69 of the upstanding wall 66 facing the interior of 
the trailer 10. The receptacle 36 thus presents an opening which faces the 
rear portion of the trailer 10. This opening in the receptacle 36 permits 
the second end 28 of the bow member 20 to be pivoted into the receptacle 
36 without any significant lifting of the bow member 20. Likewise, the 
second end 28 of the bow member 20 can be easily pivoted out of the 
receptacle 36 by pivoting the bow member toward the rear of the trailer 
10. A short retaining wall 68 is attached to the rearward facing portion 
of the receptacle 36 and acts to provide a small obstacle to otherwise 
free pivotal movement of the second end 28 of the roof bow 20 into and out 
of the receptacle 36. It will be appreciated that, in the absence of the 
retaining wall 68, the second end 28 of the roof bow 20 may pivot out of 
the receptacle 36 before the locking bar 42 has been positioned to lock 
the second end 28 in place. By providing the short retaining wall 68, it 
is necessary to lift the second end slightly over the retaining wall 68 to 
insert it and remove it from the receptacle 36. The retaining wall 68 thus 
acts as a temporary restraint to prevent undesired premature rotation of a 
second end 28 out of the receptacle 36 during the locking or unlocking 
procedure. 
The portion 69 of the upstanding wall 66 that faces the interior of the 
trailer 10 is angled away from the second upper rail 18 toward the rear of 
the trailer 10. This angle of the portion 69 is advantageous because such 
an angle acts to permit the second end 28 of the bow member 20 to be 
easily rotated into the receptacle 36, and to be guided to the rear 
portion of the receptacle 36. Thus, it will be understood that, if the 
portion 69 of the upstanding wall 66 were straight, movement of the second 
end 28 into the receptacle 36 could be significantly more difficult, 
especially if the roof bow 20 was slightly damaged or otherwise misshapen. 
The locking portion 44 of the locking bar 42 is sized and configured to 
engage both the vertical portion of the second end 28 and the retaining 
ring 38. By engaging both the second end 28 and the retaining ring 38, 
movement of the second end 28 is prevented about all axis. Specifically, 
by engaging the retaining ring 38, the retaining ring 38 is captured 
between the locking portion 44 and the upper wall of the receptacle 36. 
Thus, vertical movement, either upwardly or downwardly, of the second end 
28 is prevented. Likewise, by engaging the vertical portion of the second 
end 28, the locking portion 44 prevents movement of the second end 28 
toward the rear portion of the trailer 10. In addition, movement of the 
second end 28 toward the front of the trailer is prevented by the wall 66 
of the receptacle 36. Thus, with the locking portion 44 in position as 
shown in FIG. 3, the second end 28 of the roof bow 20 is securely held in 
the receptacle 36 such that any undesired movement of the roof bow 20 is 
prevented. 
FIG. 4 shows in greater detail the mounting of the locking bar 42 on the 
second upper rail 18, and the function of the short retaining wall 68 in 
the receptacle 36. Specifically, FIG. 4 shows that, with the second end 28 
positioned within the receptacle 36, a small portion of the extreme distal 
end of the second end 28 extends below the retaining wall 68. Thus, with 
the second end 28 positioned in a receptacle 36, and before the locking 
bar 42 has been rotated to a locked position, the second end 28 must be 
elevated slightly before it can be rotated toward the rear of the trailer 
10 and out of the receptacle 36. Although the second end 28 needs to be 
lifted only a small amount, such lifting does ensure that undesired 
premature movement of the second end 28 out of the receptacle 36 is 
prevented. 
To mount the locking bar 42 on the second upper rail 18, a spacer 76 is 
provided to ensure a proper spacing between the pivoting locking bar 42 
and the rail 18. It will be understood that different sizes of spacer 76 
may be utilized to adjust the distance between the rail 18 and the locking 
bar 42. This adjustment and spacing may be necessary to accommodate 
different trailer types, and specifically to accommodate different 
positions of a receptacle 36 on different types and styles of trailers. 
In use, and assuming that all of the roof bows 20 are in a storage position 
(not shown) in which the roof bows 20 have been pivoted about their first 
ends 26 so that they are flush and generally aligned with the first side 
wall 12 of the trailer 10, free access to the interior of the trailer 10 
is provided. To reposition the roof bows 20 so that the cover 24 may be 
installed, each roof bow 20 is pivoted manually so that the second end 28 
is moved toward the receptacle 36 by the operator. The operator then must 
lift the second end 28 of each roof bow 20 over the retaining wall 68 and 
position the second end 28 in the receptacle 36. As discussed above, the 
retaining wall 68 acts to temporarily hold the second end 28 in this 
position. The operator continues to position each roof bow 20 in the 
corresponding receptacle 36 in like manner. 
After all of the roof bows 20 are positioned with each second end 28 in a 
corresponding receptacle 36, the handle 60 is rotated in a direction of 
arrow 64 (FIG. 2) until the handle 60 is flush with the second side wall 
14. This causes the linkage bar 52 to move in the direction of arrow 65 
(FIG. 2) which pivots each locking bar 42 to an orientation shown in FIG. 
3. Thus, in the orientation as shown in FIG. 3, the second end 28 of each 
bow member 20 is securely locked within each corresponding receptacle 36. 
The handle 60 is then placed in the handle lock 62 to lock the linkage bar 
52 in the orientation shown in FIG. 3. With the roof bows 20 thus 
positioned, the cover 24 may then be placed in position and a trailer 10 
is ready for transit or storage. 
To unlock the roof bows 20 to gain access to a trailer 10, the reverse 
procedure to the above is followed. The handle 60 is removed from the 
handle lock 62 and rotated in the direction opposite the arrow 64. This 
moves the linkage bar 52 in the direction opposite the arrow 65 to 
position all of the locking bars 42 to the unlocked position away from the 
corresponding receptacles 36. The operator then lifts the second end 28 of 
each roof bow 20 out of each corresponding receptacle 36 and pivots each 
roof bow 20 to the storage position as discussed above. 
Thus, the present invention provides a roof bow system in which the roof 
bows are easily moved to a storage position, and likewise are easily 
positioned to a use position where the cover may be installed. The common 
actuation system permits easy locking and unlocking of the roof bows with 
one motion of the actuation system. After the roof bows are unlocked, they 
are easily moved to an out of the way position. This permits easy 
change-over of the trailer from its use configuration with the cover 
installed to a configuration where access is permitted in the trailer 
body. In addition, damage to the roof bows is prevented because of the 
ease of locking and unlocking each roof bow. 
Although the invention has been described in detail with reference to a 
preferred embodiment and specific examples, variations and modifications 
exist within the spirit and scope of the invention as described in the 
following claims.