CA2055766A1 - Hull conforming flexible bunk unit for boat trailer - Google Patents

Abstract

Abstract of the Invention A boat trailer having elongated bunk units supported fore and aft on the trailer by respective bracket units which are longitudinally and transversely adjustable with the fore bracket unit vertically adjustable, with both bracket units supporting the bunk units so as to be rockable about a normally horizontal axis longitudinally of the trailer and boat, and in a modification with a bracket unit mountable on a trailer crossbar in such a manner as to be pivotal with or to pivot relative to the crossbar about an axis transverse the longitudinal axis of the trailer, providing both a full engagement and conformity of the bunks with the hull of the boat and an automatic nesting engagement with the boat hull, accommodating the bunk units to the great variety of hull configurations.

Description

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~Hull Conforming Flexible Bunk Unit for Boat Trailer~
Technical Fleld The present invention related to boat trailers in general, and in particular to bunk-type trailer~ ~or transporting a variety of boats of the pleasure hoat type.
Background Art With an ever increasing number of different sized, shaped and weighted boats due to the increasing popularity of this industry, it is recognized that the trailer must securely support the boat carried thereby, and that the boat hull supporting elements guicXly conform to the contour of the hull for proper distribution of the weight of the boat and to avoid localized stresses.
Adequate weight distribution for the massive hulls supported by these modern tandem-type boat trailers provides relative ease of maneuverability during loading and launching, and steady towing characteristics. A number of different styles of bunk :~
and roller-type boat trailer~ attempt to provide such weight distribution by having a plurality of longitudinally and laterally spaced areas of weight support; one under the keel at the front, another above the wheel axle, and another at the rear of the keel.
Although a definite improvement over past trailers, a full line conformity of the support for maximum hull support is not completely attained in certain instances of hull configurations.

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2 ~5;5~7~6 ~iS~Q~ Q~ the_Inven~iOn A bo~ tr~llQr ls provlded whlcll ~upuort~ the boat firmly along each side of the hull from front to rear in a parallel-type configuration with the bunks supported at a plurality of longitudinally spaced points to allow the ~unks to flexibly conform to the hull contour for equal weight distribution.
The trailer improvement includes a front crossbar which is adjustably mounted near the front of thP
lo trailer for movement forwardly and rearwardly of the trailer side frame members; a rear crossbar which also is adjustably mounted near the rear of the trailer ~rame msmbers for fore and aft movement thereon; a pair of elongated, parallel, transversely spaced bunk units for engaging the boat hull; a first set of identical bunk support units mounted in transversely spaced relation on the front crossbar, each first support unit mounted for vertical and lateral or ~ransverse adjustment on the front crossbar, each first support unit also pivotally supporting a bunk unit for rockable movement about an axis parallel to the longitudinal axis of the trailer; and a 8 cond set of identical bunk support units mounted in transversely spaced relation on the rear crossbar, each second support unit mounted for lateral or transverse adjustment on the rear crossbar, each second support unit also pivotally supporting a bunk unit for rocXable movement about an axis parallel to the longitudinal axis of the trailer.
Further, where conventional bunks are rigldly fixed at two or three places on solid cross members or crossbars, the instant invention provides in one example for the ~ixin~ of each bunk at a ~ront cross member only; the rear section of each bunk being mounted at two longitudinally spaced points on a bracket member which i8 attached to a pivotal rear cross member or crossbar. The rear ~ection therefore acts independently in supporting the heaviest portion . . , . ,;`. !: ; , . :
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of the boat, a di~tinc~ advantage in that the bunk~ are ~ree to naturally support tlle bo~t ~nd absorb sllock that would normally transfer directly to the hull.
Still further, equal weight distribution longitudinally of and on either side of the hull of the boat being transported is enhanced by providing not only a rear crossbar unit which supports the rear of each bunk unit at longitudinally spaced supportiny points, and which unit provides for a rocking or pivoting of the supporting pivots about a transverse horizontal axis, but also by providing a front crossbar unit which supports the front of each bunk unit in functionally the same way with the same result as the rear crossbar unit. By this arrangement, each bunk unit may be free to tend to flex within a vertical plane between and amon~ up to four lon~itudinally spaced supporting points. Thus the pressure between the trailer and the hull of the boat is constantly being monitored, such that if there is a change in the ride, the support of the bunk units instantly adjust so that the pressure remains constant~
It is an object of this invention to provide an improved boat trailer.
It is another object o~ this invention to provide fore and aft adjustably mounted support devices for the laterally spaced, longitudinally extended bunk units such that the bunk units tend to engage with and conform to the contour of the hull their entire length.
With the front bunk support units vertically adjustable, and with both front and rear bunk support units supporting a bunk unit for pivotal movement about a substantially horizontal axis running parallel to the trailer longitudinal axis, the arrangement tends to conform the flexible bunk unit to the boat hull in a nesting manner for maximum hull support, ensuring equal weight distribution.
It is still another object of this invention to : , . ~ .. , . ~ .
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.' , provide support for laterally spaced, parallel and longltud~nally extellded bunk un1t~ wllereby the bunk units may flex between two or more ~upporting points, and with one or more pairs of supporting point~ capable of rocking in tandem about a transverse, normally horizontal axis relative to the trailer.
In a modification, with both front and rear bunk support units pivotal or xockable about a ~ubstantial horizontal axis transverse the trailer longitudinal axis, and with each bunk support unit providing a pair of longitudinally spaced supporting points for the bunk unit supported thereby, whereby the bunk unit is free to t~nd to flex between and about the supporting points in a vertical plane, again the arrangement tends to quickly conform the flexible bunk units to the boat hull under all conditions of the ridel thus ensuring equal weight distribution all along both sides of the hull.
Another object of this invention is to provide a supporting unit for one of the boat trailer bunk units, wherein the supporting unit is pivotal about a normally horizontal axis transverse of the trailer, and further wherein the bunk unit is free to tend to flex in a vertical plane relative to the supporting unit.
Yet another object of this invention is the provision of a bunk supporting unit including a mounting bracket adapted to 6upport a bunk supporting channel in either a stationary or a pivoting manner to accommodate either a stationary or pivoting cross member.
Brief Description of the Drawings These and other attributes of the lnvention will become more clear upon a thorough study of the following description of a preferred embodiment of the 3S invention, particularly when reviewed in co~ unction with the accompanying drawings, wherein:
Fig. 1 is a perspective view of a boat trailer of . , . , , , : .

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the present invention;
Fig. 2 i~ a plan view of the boat tra~ler of Fig.
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Fig. 3 is a ~ide elevational view of the boat trailer of Fig. 1 as taken ~rom the right side thereof;
Fig. 4 is an enlarged fragmentary, sectional view taken along the line 4-4 in Fig. 2;
Fig. 6 is a fragmentary, sectional view taken along the line 6-6 in Fig. 2;
Fig. 7 is a sectional view taken along the line 7-7 in Fig. 6;
Fig. 8 is a perspective exploded view of a modified bunk supporting unit;
Fig. 9 is a fragmentary sectional view similar to the view of Fig. 6, showing the modification o~ Fig. 8 in place at the rear of the boat trailer;
Fig. ~0 is a sectional view taken along the line 10-10 in Fig. 9; and Fig. 11 is a fragmentary sectional view of the Fig. 8 modification in place at the front of the boat trailer.
Best Mode for Carryinq out the Invention This is a continuation-in-part of my co-pending application Serial No. 07/447,675, filed Decem~er 8, l9B9, entitled Hull Conforming Bunk Unit for Boat Trailer.
Although not intended to be so limited, for convenience of illustration the improved boat trailer bunk mounting system of this invention is shown in connection with a trailer for loading and supporting a low or shallow draft-type boat. The illustrated trailer construction enables the boat to be loaded directly ~rom the water by backing the ~railer down a ramp or incline and bringing the rearmost hull engaging bunk assemblies o~ the trailer into position close to the floating boat. The boat is then advanced into contact with the bunk assemblies and drawn forward into - . . . . . .: .

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supporting engagement therewith and with the forward keel ~upporting structur~ for full engagemellt and support of the boat for purposes of transportation.
Referrin~ now to the drawings, particularly Fig.
1, the boat trailer of this invention is illustrated generally at (lo) and comprises a frame assembly (11~
including a tongue (12) and hitch ~13) for conventio~al attachment to a prime mover (not shown); a winch assembly (14) for detachable connection to a boat (not shown) to be transported thereby; a stand assembly (16) for supporting the frame assembly (11) in a horizontal condition; a front keel supporting assembly (17) pivotally mounted on a front crossbar assembly (18); a wheel and axle unit (19) for supporting the frame assembly (11) adjacent the rear end thereof; a rear crossbar assembly (21) pivotally connected to the frame assembly (11); a pair of bunk units (22) and (23) each secured in transversely spaced, parallel relation to the front and rear crossbar assemblies (18) and (21);
and a pair of guide members (24), (26) for guiding the boat to be transported by the trailer (10) onto and off of the trailer ~10).
Let it be noted that the frame assembly (11) has an A-shape with converged portions of the frame assembly (11) forming the tongue (12), and with outwardly diverging frame members (27) and (28) including the fore part of the frame assembly (11), with parallel and rearwardly extending frame members (29) and (31), completing the frame assembly (11), the rear frame members (29) and (31) extsnded parallel each other and to the longitudinal axis of the frame assembly (11). The rear crossbar assembly ~21) comprises a slightly V-shaped crossbar (32) whi~h has a pair of brackets (33), ~3~) connected at each outer end thereof for plvotal mountlng to the respectlve rear frame members (29), ~31).
The improvement comprises a front crossbar (36) of , , : . .
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~5~7~16 the a~embly (1~), which cro~sbar (36) 1~ ~ecured to and extended transversely between the frame members (29), (31) forwardly of the wheel and axle unit (19);
the rear crossbar (32) secured to and extended transversely between the frame members (29), (31) rearwardly of the wheel and axle unit (19); the bunk units ~22), (23) which are disposed parallel the longitudinal axis of the trailer (lO); a first set of identical bunk support units (37), (3~) mounted in transversely spaced relation on the front crossbar (36), each bunk support unit (37), (38) adjustable vertically and laterally on the front crossbar (36), and pivotally supporting forward portions of one of the bunk units (22), (23) for rockable movement about an axis parallel the trailer (10) longitudinal axis; a second set of identical bunk support units (39'), (41') (Figs. 6 and 7) mounted in transversely spacPd relation on the rear crossbar (32), each second bunk unit (39~), ~41') adjustable laterally on the rear crossbar (32) and pivotally supporting rearward portions of one of the bunk units (22), (23) for rockable movement about an axis longitudinally aligned with the pivotal axis of ona of the first bunk units and also with the trailer longitudinal axis.
Referring to the drawings, the front crossbar assembly (18) comprises the front crossbar (36) the outer ends of which are welded to C-shaped brackets (42) (Fig. 4) adjustably engaged with the respective side frame member (29) and (31), bolt units (43) inserted through alignable openings (not shown~ formed in each bracket (42) and formed in longitudinally spaced relation along each frame member (29), (31) for longitudinal adjustability of the front crossbar assembly (18) relative to the trailer (10).
The rear crossbar a~sembly (21) a~ ment~oned hereinbefore includes a pair of brackets (33~, (34) at the outer ends of the crossbar ~32) (Fig. 7), and again . . : :, .
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~S766 by the provision of a bolt unit (44) and approprlate allgnable openlngs (not ~hown) formed ln the brackets (33), (34) and the rear portions 3g th~ frame members (29), (31), the rear crossbar assembly is also longitudinally movable from one fastened position to another on the frame members (29), (31), the rear crossbar assembly is also longitudinally movable from one fastened position to another on the frame members ~29~, (31).
lo Each bunk unit (22), (23) is identical, comprising an elongated, flexible member (46) (Fig. 4) of wood or like material, covered by a durable padded element (47) for hull protection.
As the first bunk support units (37), (38) are identical, only one (37) (Fig. 4) will be described.
This unit (37) comprises an elongated U-shaped element (48) having a base portion (49) with longitudinally spaced openings (51) formed therein, and with the basa portion (49) having a top end (52) with a flat surface.
By the provision of a pair of fastening units (53) adapted to engage spaced ones of the openings (51), the element (48) is vertically, adjustably mounted on the front crossbar ~36), as well as being transversely adjusta~le thereon to accommodate the various sized and contoured boat hulls.
Each first bunk unit support (37) also comprises an L-shaped second element (54) (Fig. 4) having a flat base (56) with upstanding legs (57) at each end, and with a depending portion (58) at one side of the base (56). As seen in Figs. 4 and~5/ the legs (57) embracP
and are secured to a bunk unit (22) by a fastener (59), and the portion (58) is pivotally connected by another fastener (61) along a normally horizontal axis parallel the longitudinal axis of the trailer (10), and with ~he bottom surface of the base ~563 spaced above the upper surface of the first element top end (5Z). By this arrangement, the upper element (54) and the attached . ~ ,:. ~: . .

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~ ~ ~ S ~ ~6 bunk unit t22) can rock about an axi~ parallel the tra~ler longitudlnal axis.
With the second bunk support unit~; ( 3 9 ' ), ( 4 1 ' ) ~41' not being 6hown~ being identical, only the unit 5 (39') (Figs. 6, 7) will be described.
Unit (39') comprises an elongated tubular mPmber (62'), square shaped in cross section and connected as by welding to a plate ( 63 ' ) secured in turn to the crossbar (32) by U-clamps (64~) for lateral adjustment thereon.
At each end of the member (62'), an L-shaped element (82) is provided, one depending leg (~3) pivotally secured by a fastener (84) to an end (85) of the element (82), and another leg (86~ secured to the base of the bunk member (46) in a spaced rela~ion to the upper surface (87) of the member t62~), as by upturned projections (88) secured to the sides of the bunk uni~ (22) by fasteners (89). The bunk support unit (39') permits the bunk unit (21) to rock about an axis parallel the trailer longitudinal axis and in line with the front bunk support units (37), (38).
A modified second bunk support unit (91) (Figs. 8-ll) is provided as a substitute for both the front bunk support units (37), (38) and the rear bunk support units (39'), (41') in a manner hereinafter described.
The support unit (91) comprises a V-shaped channel (90) (Fig. 8~ having a base (92) with a pair of longitudinally spaced openings (93), (94) formed therein and a pair of upstanditlg legs (96), (97) each having ~hree pair of vertically spaced holes (98)/ (99) and (101) formed therein, each pair of holes in each leg transversely aligned with an opposite pair of holes as best illustrated in Fig. 8.
The support unit (91) also comprises an elongated bracket unit (102) ~Flg. 8), having a U-~haped bracket (103), including a top (104), sides (106~, (107) and inwardly extended flanges ~108); a splice ~109) secured . . . , '., ' ~ ' . ' '~1 2~S~7~6 centrally to the bracket ~103) across ~he flange~
~108); a plate (111) secured ad~acellt one end of the bracket (103) also across the f langes ~ 10~ ); and a pair of end plates (112), ~113~, each with an opening (114) formed therein, secured across each open end of the bracket (103). Centrally of each side (106), (107) a trio of vertically spaced pairs of holes (116), (117), (118) are formed in transversely aligned relationship.
Figs. 9 and 10 disclose ut~lization of the modified bunk support unit (91) for supporting a rear portion (116) of one of the bunk units (22) similar to the Fig. 6 arrangement. The channel (90) is mountsd on the crossbar (32), pivotally connected to the frame members (29~, (31) by bracket~ (33'), by its base (92~
(Fig. 9) with a U-bolt fastener (119) inserted through the base openings (93), ~94), and whereby the support unit (91) is adjustably mounted longitudinally on the crossbar (32). The bracket (102~ is supported within the upwardly open channel (90) and secured thereto by a pair of fasteners (121) inserted through aligned pairs of channel holes (981 and bracket side holes (11~), and channel holes (101) and bracket side holes (118~ (Fig.
9) . ., At each end of the bracket unit (102), an L-shaped element (82) is provided, one depending leg (83) pivotally secured by a fastener (84) to an end (85) of the unit (102), and another leg (86) secured to the base of the bunk member (46) in spaced relation to the upper surface (87) unit (102), by upturned projections (88) secured to the sides of the bunk unit (22) by fasteners. In addition to the bunk support unit (91) rocking about a substantially horizontal axis transverse the trailer longitudinal axis, the unit (91) also supports the bunk unit portion (116) to pivot about a normally horizontal axis parallel the trailer longitudinal axis, and further the bunk unit portion (116) is free to tend to ~lex in a vertical plane .~

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between the supporting points formed by the elements (82).
Fig. 11 discloses a utilization of the modified bunk support unit (91) replacing the front bunk support unit (37) of Figs. 4 and 5. The assembly is substantially identical to that on the rear crossbar (~2) of Figs. g and 10, with the exception that a fastener (122) is inserted instead through aligned central channel holes (99) and bracket side holes (117) such that the bunX support unit (91) pivots or rocks about a substantial transverse axis relative to the boat trailer longitudinal axis via the fasteners (121), but with the unit (91) then supporting the forward bunk unit portion (123) in a substantially identical manner as it supports the rear bunk unit portion (116).

Claims (8)

1. A bunk assembly for supporting a boat on a trailer wherein the trailer includes a pair of laterally spaced frame members supported by a wheel and axle unit, the improvement comprising:
a front crossbar secured to and extended transversely between the frame members fore of the wheel and axle unit;
a rear crossbar secured to and extended between the frame members aft of the wheel and axle unit;
at least a pair of elongated bunk units, each bunk unit extended parallel the other bunk unit and spaced transversely therefrom, with both said bunk units disposed parallel the longitudinal axis of the trailer;
first means secured to said front crossbar and to a front portion of each bunk unit at a first supporting point for mounting each said bunk unit front portion onto said front crossbar;
second mounting means secured to said rear crossbar for supporting each of said bunk units at second and third supporting points along the length of each of said bunk unit, said first, second and third supporting points being longitudinally spaced apart from each other; and means for pivoting said second mounting means about an axis transverse to the longitudinal axis of the trailer.

2. The bunk assembly of claim 1, and further wherein said front crossbar is adjustably mounted on the frame member rear ends for movement thereon longitudinally of the frame members.

3. A bunk assembly as in claim 1, wherein said rear crossbar is adjustably mounted on the frame member rear ends for movement thereon longitudinally of the frame members.

4. A bunk assembly as in claim 1, wherein each bunk support unit of said second set of bunk support units includes a first elongated element mounted on said rear crossbar for laterally adjusted positions, and a second elongated element pivotally mounted on said first element.

5. The bunk assembly of claim 1, and further wherein said means for pivoting said second mounting means comprises a unit pivotally securing each end of said rear crossbar to an adjacent one of said laterally spaced frame members.

6. A bunk assembly for supporting a boat on a trailer wherein the trailer includes a pair of laterally spaced frame members supported by a wheel and axle unit, the improvement comprising:
a front crossbar secured to and extended transversely between the frame members fore of the wheel and axle unit;
a rear crossbar pivotally secured to and extended between the frame members aft of the wheel and axle unit;
at least a pair of elongated bunk units, each bunk unit extended parallel the other bunk unit and spaced transversely therefrom, with both said bunk units disposed parallel the longitudinal axis of the trailer;
first means pivotally secured to said front crossbar for supporting each of said bunk units at a first pair of longitudinally spaced supporting points;
and second means secured to said rear crossbar for supporting each of said bunk units at a second pair of longitudinally spaced supporting points.

7. The bunk assembly of claim 6, and further wherein said first and second bunk units supporting means supports said bunk units such that said bunk units are free to tend to flex within a vertical plane between said supporting points.

8. The bunk assembly of claim 7, and further wherein said first and second bunk supporting means includes a bracket at each supporting point, each said bracket pivotally mounting said bunk unit, whereby said bunk units re pivotal about a normally horizontal axis parallel the longitudinal axis of the boat trailer.