US3734046A - Floating dry dock - Google Patents

Abstract

A floating dry dock consisting of a buoyant platform having a section adapted to be pivoted downwardly to form a ramp extending at its free edge beneath the water level, and up which a boat may be pulled from the water to the platform, the ramp section having sufficient buoyancy to support the boat, or that portion of the boat weight eventually supported thereon, cable mechanism for pivoting the ramp section downwardly against its natural buoyancy, cable mechanism for pulling a boat upwardly along the ramp section, locks for holding the ramp section releasably in its elevated position, and supports on the platform and ramp section for carrying the boat.

Description

United States Patent [1 1 Schmidt et al.

[541 FLOATING DRY DOCK [75] Inventors: Otto W. Schmidt, Leawood; Richard O. Schmidt, Prairie Village, both of Kans.

[73] Assignee: The Firman L. Carswell Manufacturing Company, Kansas City, Kans.

[22] Filed: May 10, 1971 [21] Appl. No.: 141,865

[52] US. Cl ..ll4/0.5, 114/435 [51] Int. Cl. ..B63b 35/00 [58] Field of Search ..114/0.5 R,43.5,

[56] References Cited UNITED STATES PATENTS 1,300,954 4/1919 Gray ..1 14/435 [111 3,734,046 51 May 22, 1973 FOREIGN PATENTS OR APPLICATIONS 22,916 /l9l3 Great Britain ..1 14/435 Primary Examiner-Milton Buchler Assistant Examiner-S. D. Basinger Attorney-John A. Hamilton [57] ABSTRACT A floating dry dock consisting of a buoyant platform having a section adapted to be pivoted downwardly to form a ramp extending at its free edge beneath the water level, and up which a boat may be pulled from the water to the platform, the ramp section having sufficient buoyancy to support the boat, or that portion of the boat weight eventually supported thereon, cable mechanism for pivoting the ramp section downwardly against its natural buoyancy, cable mechanism for pulling a boat upwardly along the ramp section, locks for holding the ramp section releasably in its elevated position, and supports on the platform and ramp section for carrying the boat.

8 Claims, 9 Drawing Figures FLOATING DRY DOCK This invention relates to new and useful improvements in boating gear, and has as its principal object the provision of a device in the general nature of a floating dry dock, whereby a boat, particularly a small pleasure craft, may be conveniently and safely stored out of the water and dry. This protects the boats hull and motor against dangerous overexposure to water, electrolysis and against harmful marine growth, provides a secure mounting so that the boat does not rock or bump against its dock as is usually the case, reduces corrosion to the motor and boat hardware, and provides for boat repair and maintenance work which cannot be accomplished when the boat is in the water.

Another object is the provision of a floating dry dock of the general character described in which the boat supporting and moving gear is removable from the basic platform of the dock, whereby said platform may serve as a swimming or party dock.

A further object is the provision ofa floating dry dock of the character described which requires not outside power of any kind but is operable entirely by manual means, but which nevertheless is operable easily even by children or ladies.

Other objects are simplicity and economy of construction, efficiency and dependability of operation, and adaptability for use with boats of many different sizes, types, and styles.

With these objects in view as well as other objects which will appear in the course of the specification, reference will be had to the accompanying drawing, wherein:

FIG. 1 is a top plan view of a floating dry dock embodying the present invention,

FIG. 2 is an inverted plan view of the dry dock,

FIG. 3 is an enlarged rear elevational view of the dry dock, with parts omitted and broken away;

FIG. 4 is an enlarged, fragmentary sectional view taken on line IV-lV of FIG. 1,

FIG. 5 is an enlarged, fragmentary sectional view taken on line V-V of FIG. 1, with parts left in elevation and partially broken away,

FIG. 6 is a fragmentary sectional view taken on line VI-Vl of FIG. 5, with parts left in elevation and partially broken away,

FIG. 7 is an enlarged, fragmentary sectional view taken on line VIl-VII of FIG. 1,

FIG. 8 is a fragmentary sectional view taken on line VIII-VIII of FIG. 7, and

FIG. 9 is a fragmentary sectional view taken on line IX-IX of FIG. 1, showing the dock in the water and a boat in the process of being loaded thereon.

Like reference numerals apply to similar parts throughout the several views, and the numeral 2 applies generally to the mainplatform of the dock. Said platform is generally planar, consisting of a grid-like substructure 4 which may be formed of structural steel or the like, a planar floor 6 overlying and affixed to said substructure, and flotation blocks 8 distributed over the lower surface of the substructure and affixed thereto by any suitable means, not shown. Said flotation blocks may consist of a large slabs of foamed plastic or other suitable buoyant material, and serve to float the dock in the water. The platform as shown is horizontally rectangular, but could obviously be of any other desired horizontal contour.

At the right end of the dock as shown in FIGS. 1 and 2, which is its rearward end, platform 2 is notched out to form a rectangular well 10. Said well opens through the rearward end of the platform and is disposed midway between the sides of the platform, whereby portions of said platform walkways 12 along each side of said well. Disposed within well 10 is a rectangular ramp section 14 of the dock. Said ramp section is provided with a substructure l6, floor 18 and flotation blocks 20 in the same manner as platform 2, is of somewhat smaller horizontal dimensions than well 10, although it may project somewhat rearwardly of said well as shown, and is pivoted at its forward edge to said platform by means of pivots 22, for vertical movement of the rearward end thereof. Said ramp section is coplanar with platform 2 when the former is fully elevated, and may be releasably locked in said elevated position by locking devices 24 best shown in FIGS. 7 and 8, disposed at each side of said ramp secton in rearwardly spaced relation from pivots 22. Each of said locking devices constitutes a horizontal plate 26 affixed to platform 2 at one side of well 10 and extending toward the adjacent edge of ramp section, 14, a horizontal plate 28 affixed to the adjacent edge of ramp section 14 in alignment with plate 26 and extending toward the adjacent edge of well 10 to underlie plate 26, and a C-shaped keeper 30 mounted slidably on plate 26 and having depending hooked end portions 32 adapted to be moved into or out of underlying relation to plate 28 by sliding movement of the keeper on plate 26. Thus plates 26 serve to limit the upward movement of plates 28, so that ramp 14 can never rise higher than a coplanar relation to platform 2, and the ramp secton can be positively locked at this upper limit by moving keepers 30 to engage hooks 32 thereof beneath plates 28. At its inner end, each plate 26 is provided with an upstanding lip 34 for preventing accidental disengagement of its keeper therefrom.

At its rearward end, and midway between its sides, ramp section 14 is notched out to form a rectangular well 36 adapted to accommodate the propeller and propeller column of a boat equipped with an outboard motor. At the respectively opposite sides of well 36, at the rearward end thereof are disposed a pair of inwardly and downwardly inclined guide rollers 38, said rollers being carried rotatably by brackets 40 affixed to the substructure of the ramp section. Distributed along the midline of platform 2 and of ramp section 14 are a seriesof keel rollers 42, said rollers being rotatable on horizontal axes transverse to the dock, and disposed somewhat above the surface of the dock. One of said rollers should be disposed at the forward edge of well 36 of the ramp section, and one at the extreme forward edge of said ramp section, with others spaced more or less regularly along the length of the ramp section and platform 2. As best shown in FIGS. 5 and 6, each keel roller 42, which may be spool-shaped as shown and formed of rubber or the like, is mounted on an axle 44 mounted rotatably in a bracket 46 including a base plate 48 resting on the floor of the platform or ramp section. Rigidly affixed to and depending from said base plate are a pair of spaced apart posts 50 which extend downwardly through holes 52 formed therefor in said floor and are engaged slidably in a pair of tubular sockets 54 welded to a plate 56 affixed to the dock substructure by bolts 58. Thus rollers 42 and their brackets 46 may be lifted free, in order to clear the dock floor when desired.

Mounted on ramp section 14 are sets of cradle rollers 60 at each side of the midline therefor. The cradle rollers at each side of the midline are rotatable on axes in clined downwardly and inwardly toward the midline, and are arranged in spaced relation along most of the length of the ramp, whereby to engage the hull of a boat the keel of which is supported by keel rollers 42 of said ramp. The cradle rollers 60 at each side of the dock midline are mounted on bars 62 extending longitudinally of the ramp above the surface thereof, said bars being affixed to support standards 64 which are in turn affixed to floor 18 of the ramp by any suitable means, not shown. It will be understood, however, that the cradle rollers, together with bars 62 and standards 64 supporting them, may be detached from the ramp to clear the top of the dock when desired.

At the forward end of dock platform 2 there is disposed a winch post 66 projecting upwardly from said platform. As best shown in FIG. 4, the lower end of said post is engaged selectively and removably in any one of a plurality of socket members 68 affixed to the dock substructure, holes 70 being formed in platform floor 6 to admit said post. Said sockets are spaced along the midline of the dock platform, and depending on the variety of the lengths of the boats it may be desired to load on the dock, any desired number of sockets could be provided.

Mounted on winch post 66 are a pair of winches 72 and 74. Winch 72 includes a drum 76 rotatable by means of a manual crank 78 and having wound thereon a cable 80 to the extended free end of which is secured a hook 82 adapted to be engaged in an eye 84 provided at the prow of a boat 86 (see FIG. 9). Winch 74 includes a drum 88 operable by a manual crank 90 and having wound thereon a cable 92 to the depending free end of which is secured to a snap fastener 94. To the forward edge of the substructure 16 of ramp section 14 there are affixed a pair of depending angle irons 96 (see FIGS. 2 and 9), said angle irons being reinforced by a tie bar 98 extending therebetween adjacent their lower ends, and braced by a pair of cables 100 each secured at its rearward end to the lower end of one of angle irons 96, as at 102, and secured to its opposite end to a bracket 104 affixed to the corresponding rearward corner of the ramp, as at 106. A cable 108 is secured at its respective ends to the lower ends of angle irons 96, at at 110, and extends forwardly beneath the dock platform, extending slidably, at the forward end of the resulting V-shape assumed thereby, through an eye 112 (see FIG. 4) affixed to the rearward block 114 of a block-and-tackle device 116, the forward block 118 thereof being attached to a pin 120 affixed to and depending from the forward edge of the substructure of the platform. The operating cable 122 of the blockand-tackle is trained around a pulley 124 rotatably mounted on a bracket 126 secured to the substructure by a bolt or other fastener 128, and upwardly through a hole 130 provided therefor in platform floor 6. Above said floor, said cable is secured in a ring 132 which is too large to pass downwardly through said hole, and snap fastener 94 of winch cable 92 is secured releasably in said ring. Holes 130 in the floor, as well as bolt holes 134, are provided in proper relation to each of said sockets 68, to accommodate cable 122 and provide for the mounting of pulley 124 regardless of which socket may be used to receive winch post 66. Block-andtackle device 116 of course provides a substantial mechanical advantage in the operation of winch 74. It will be understood also that both of winches 72 and 74 are provided with the usual gear drives from their cranks in order to provide a still greater mechanical advantage, and that both winches are equipped with the usual ratchet and pawl devices for releasably locking the winch drums at any desired position in their rotation.

To load a boat 86 in the dock, keel rollers 42 and cradle rollers 64) are positioned as shown and described, rarnp locks 24 are disengaged as previously described, and crank 96 is turned to cause winch 74 to reel cable 92 in. This pulls cable 122 of block-and-tackle 116, which in turn acts through cable 108 and angle iron posts 96 to pivot the rearward edge of ramp section 14 downwardly to a position at least slightly below the water level 136, as shown in FIG. 9. The sliding of cable 108 in eye 1112 of the block-and-tackle insures a balanced downward force at both sides of the ramp. The natural buoyancy of the ramp section must be overcome in this operation, and this requires a heavy pull, but can be accomplished even by ladies or children due to the mechanical advantage provided by the winch and by block-and-tackle 116. This operation also has a tendency to elevate dock platform 2 in the water, at least the rearward edge thereof, but not significantly if the platform weight and area is sufficiently large in comparison to that of the ramp section. The boat is then maneuvered in the water to face the rearward edge of the dock, substantially in alignment with the midline of the dock, and hook 82 of cable of winch 72 is engaged in eye 84 of the boat. Winch 72 is then operated to pull the boat forwardly up ramp section 14, as clearly shown in FIG. 9. Ideally, the prow section of the boat hull is first engaged by inclined guide rollers 38, which laterally center the boat relative to the dock, and the extreme prow or forward keel section then engaged by the rearmost keel roller 42, the guide rollers and rearmost keel roller then lifting the boat, as it is moved forwardly, to an elevation sufficient that it engages cradle rollers 60, which support it against lateral tilting. As the prow of the boat is initially elevated, but before it is supported by the cradle rollers, the stern section thereof is still in the water and supported thereby against lateral tilting.

Preferably as soon as the center of gravity of the boat passes over rearmost cradle rollers, operation of winch 74 is started to pay out cable, so that the ramp section is pivoted upwardly by its buoyancy, so that when said center of gravity passes over the forwardmost cradle rollers, said ramp is level and the boat is positioned to engage the keel rollers 42 carried by the dock platform. Ordinarily the boat is pulled forwardly to snub it against winch 72, whereby to prevent forward or rearward movement of the boat on the rollers, with the stern portion engaged by cradle rollers 60 to prevent lateral tilting, and the depending propeller column and propeller of the boat (not shown), if the boat is so equipped, disposed in rear well 36 of the ramp. It will be understood that the buoyancy of ramp 14 is sufficiently great to rise to coplanar relation with the dock platform, even when it is supporting the entire weight of the boat, or at least that portion of the boat weight which is eventually supported thereby. Consequently the ramp would rise still higher at any time it is not carrying a boat, were it not for the stop action of plates 26 and 28 of ramp lock devices 24. Nevertheless, it is still generally desirable to re-engage said lock devices after the ramp is fully elevated, since while the ramp would ordinarily remain fully elevated anyway, it is possible that wave action in the water beneath the dock could cause vertical oscillation of the ramp. The boat is unloaded rearwardly simply by generally reversing the loading procedure just described, except of course that the boat must be pushed rearwardly by manual force until it enters an inclined position on the ramp, after which it enters the water by gravity. This rearward rolling of the boat is easily performed if the supporting rollers are well lubricated.

Thus it will be apparent that a floating dry dock having many desirable features has been produced. it is simple and relatively inexpensive in structure, can be operated easily even by women, while at the same time requiring no source of outside power. Besides all the advantages of dry boat storage previously enumerated, dock platform 2, and particularly walkways 12 thereof, offer ready access to virtually every part of the boat and its hull for maintenance and repair work. Also, by unsnapping fastener 94 from ring 132 and lifting winch post 66 from its socket 68, and by removing the cradle and keel rollers as described, the entire floor of the dock may be completely cleared for use as a swimming or party dock.

While we have shown and described a specific embodiment of our invention, it will be readily apparent that many minor changes of structure and operation could be made without departing from the spirit of the invention.

What we claim as new and desire to protect by Let ters Patent is:

1. A floating dry dock comprising:

a. a generally planar, buoyant dock platform adapted to float in the water with the floor thereof above the water level,

b. a ramp pivoted at one edge to said platform for vertical movement between an elevated position coplanar with said platform floor to a depressed position wherein it is inclined downwardly from said platform floor and its free edge is disposed at or below the water level,

0. ramp operating means carried by said platform and operable to move said ramp between said elevated and depressed positions, said ramp being sufficiently buoyant to rise to coplanar relation with said platform floor under the weight of that portion of the weight of the boat eventually supported thereby, and wherein said ramp operating means is operable to pivot said ramp downwardly against its natural buoyancy,

d. boat supporting means carried by said platform and ramp and operable to support a boat thereon for movement transverse to the pivotal axis of said ramp, and

e. boat loading means carried by said platform and operable, when said ramp is depressed, to pull a boat supported by said supporting means up said ramp and onto said platform, whereby said boat is positioned on and supported by said platform and ramp.

2. A floating dry clock as recited in claim 1 with the addition of stop means operable to limit the upward pivoting of said ramp to the position in which it is coplanar with said platform.

3. A floating dry dock as recited in claim 1 with the addition of locking means operable to secure said ramp releasably in its elevated position.

4. A floating dry clock as recited in claim 1 wherein said ramp operating means comprises:

a. a cable affixed to said ramp and operable by tension thereon to pivot said ramp downwardly, and

b. a manually operable winch carried by said platform and including a rotatable drum on which said cable is wound.

5. A floating dry dock as recited in claim 4 with the addition of a block-and-tackle device interposed in the cable connection between said winch and said ramp, whereby the mechanical advantage of said winch is multiplied.

6. A floating dry dock as recited in claim 4 wherein said boat loading means comprises a second manually operable winch carried by said platform and including a rotatable drum and a cable wound on said drum, the extended end portion of said cable being adapted to project generally horizontally outwardly from said dock, over the ramp thereof, for attachment to a boat in the water approaching said ramp.

7. A floating dry dock as recited in claim 6 wherein both of said winches are mounted on a single post projecting upwardly from said platform, and removably mounted at its lower end in a socket provided therefor in said platform, whereby removal of said post and the winches mounted thereon assists in clearing the floor of said platform when desired.

8. A floating dry dock as recited in claim 7 wherein said boat supporting means comprises keel and cradle rollers mounted on said platform and ramp, above the floors thereof, by means easily detachable from said platform and ramp, whereby detachment and removal of said rollers and their supporting means assists in clearing the floors of said platform and said dock when desired.

Claims (8)

1. A floating dry dock comprising: a. a generally planar, buoyant dock platform adapted to float in the water with the floor thereof above the water level, b. a ramp pivoted at one edge to said platform for vertical movement between an elevated position coplanar with said platform floor to a depressed position wherein it is inclined downwardly from said platform floor and its free edge is disposed at or below the water level, c. ramp operating means carried by said platform and operable to move said ramp between said elevated and depressed positions, said ramp being sufficiently buoyant to rise to coplanar relation with said platform floor under the weight of that portion of the weight of the boat eventually supported thereby, and wherein said ramp operating means is operable to pivot said ramp downwardly against its natural buoyancy, d. boat supporting means carried by said platform and ramp and operable to support a boat thereon for movement transverse to the pivotal axis of said ramp, and e. boat loading means carried by said platform and operable, when said ramp is depressed, to pull a boat supported by said supporting means up said ramp and onto said platform, whereby said boat is positioned on and supported by said platform and ramp.

2. A floating dry dock as recited in claim 1 with the addition of stop means operable to limit the upward pivoting of said ramp to the position in which it is coplanar with said platform.

3. A floating dry dock as recited in claim 1 with the addition of locking means operable to secure said ramp releasably in its elevated position.

4. A floating dry dock as recited in claim 1 wherein said ramp operating means comprises: a. a cable affixed to said ramp and operable by tension thereon to pivot said ramp downwardly, and b. a manually operable winch carried by said platform and including a rotatable drum on which said cable is wound.

5. A floating dry dock as recited in claim 4 with the addition of a block-and-tackle device interposed in the cable connection between said winch and said ramp, whereby the mechanical advantage of said winch is multiplied.

6. A floating dry dock as recited in claim 4 wherein said boat loading means comprises a second manually operable winch carried by said platform and including a rotatable drum and a cable wound on said drum, the extended end portion of said cable being adapted to project generally horizontally outwardly from said dock, over the ramp thereof, for attachment to a boat in the water approaching said ramp.

7. A floating dry dock as recited in claim 6 wherein both of said winches are mounted on a single post projecting upwardly from said platform, and removably mounted at its lower end in a socket provided therefor in said platform, whereby removal of said post and the winches mounted thereon assists in clearing the floor of said platform when desired.

8. A floating dry dock as recited in claim 7 wherein said boat supporting means comprises keel and cradle rollers mounted on said platform and ramp, above the floors thereof, by means easily detachable from said platform and ramp, whereby detachment and removal of said rollers and their supporting means assists in clearing the floors of said platform and said dock when desired.

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