Expandable boat
United States Patent 11 1 Ivy I 54 I EXPANDABLE BOAT [76] Inventor: Jessie T. Ivy, Rt. 1. Box 350.  
 Anacortes. Wash. 98221 [22] Filed: Nov. 12, 1973 21 Appl. No.: 414.805  
 [52] U.S. CI. 9/6  
 [51] Int. Cl. B63b 3/08 [58] Field of Search 9/6. 6.5. 2 C. 2 R. 2 S. 9/1 R; 114/65 R, 71  
 [56] References Cited UNITED STATES PATENTS 1.712.167 5/1929 Pontikis 9/6 2.764,]19 9/1956 Sigler 9/6 3,266,067 8/1966 Windlc 9/2 S 3.372.408 3/1968 Luger et a1. 9/6  
 FOREIGN PATENTS OR APPLICATIONS 2.020.248 11/1971 Germany 9/6 1 1 Apr. 15, 1975 Primary Examiner-Trygvc M. BliX Assistanl Examiner-Stuart M. Goldstein Attorney, Agent. or Firm-Seed, Berry, Vernon &amp; Baynham [57] ABSTRACT An attachment for an open boat which increases the carrying capacity and stability of the vessel without altering the basic structure. An open topped extension is removably secured to the after portion of the boat and is retained in position by a combination of fasteners securing it to the transom and forwardly extending portions secured to the gunwales. The attachment may include a forward deck and windshield to provide weather protection to the occupants.  
 7 Claims, 8 Drawing Figures FISH-475M931 55:5  
 SHEET 1 0F 2 FIGO 11 FIGO 3 Men 2 FIG 5 EXPANDABLE BOAT BACKGROUND OF THE INVENTION I There are a large numberof people who own small. open boats who would like to retain the portability of their vessels and yet have the advantage of greater car rying capacity. some protection from the weather and greater stability. A further incentive lies in the desire to keep the capital investment to a minimum. Normally. in order to gain stability and greater carrying capacity. one must give up the portability and low investment and acquire a larger boat.  
  Attempts have been made in the past to convert one type of boat to another and some of these have been quite successful from a utility standpoint but have not been well received in the market place. Further. various methods of manufacturing boats are considered to beprior art in the fact. that they may utilize some of the fabricationsconcepts expressly used herein to achieve the d esired. result of a larger, more stable boat without greatly increasing the capital investment or decreasing the portability of the original structure.  
  The prior art known to the present inventor includes U.S. Pat. No. 2.376.753. granted to Bowen on May 22. I945. which teaches the method I of fabricating a molded boat of several different elements which are then secured together to form the desired embodiment of the completed structure. US. Pat. No. 2,866,985. granted Jan. 6. I959. to Blackmore. teaches the concept of a plastic molded boat which includes an integral portion filled with closed cell foam for flotation. US. Pat. No. 2.999.253. granted Sept. 12.. 1961. to Lewis. teaches the method of converting a canoe to a kayak by adding a covering or shielding portion over the open top to keep the water out in a manner similar to a traditional kayak.  
  US. Pat. No. 3.I29.443. granted Apr. 2]. 1964. to Maturi. et al.. teaches the concept of a convertible boat and includes the possibility of extending the length of the boat by adding sections fore and/or aft thereby enabling the same boat to be used as a motor boat. sail boat or the like. U.S. Pat. No. 3.133.294. granted May I&#34;). I964. to Kunz. teaches the method of fabricating a kayak type boat wherein&#39;the bottom or main. hull portion is molded in one piece and the top. shielding portion is molded as a second piece and the two elements are then secured together to form a weather-tight seal. U.S. Pat. No. 3.372.408. granted Mar. I2. I969. to Luger. et al. is yet another teaching of fabricating a boat using a sectional approach wherein the deck and side portions may be either-a single unit or a plurality of units which is secured to a hull. U.S-. Pat. No. 3.702.485. granted Nov. 14. 1972 to Thompson. teaches the concept of placing an outboard engine in a well within a boat so that it looks like an inboard boat or an inboard-outboard boat. To achieve this disceptive appearance. the rear end of the boat is actually extended beyond where it normally would terminate. U.S. Pat. No. 3.726.245. granted Apr. 10. I973, to Critcher. teaches the concept of taking a small sailing dinghy and placing it between a pair of stabilizing and supporting pontoons. thereby enabling the boat to be utilized in inclement weather and to carry more weight without danger. US. Pat. No. 3.538.877, granted Nov. l0. I970, to Moore. teaches the concept of securing two side portions to asmall boat, thereby converting a conventional boat to a&#39;catamaran.vU.S. Pat. No. 3.69l.572.  
 granted Sept. I9. 1972. to Yannes. .lr.. teaches the utilization of a removeable top deck attached to the gunwales of a canoe. including foam flotation for converting the canoe to a kayak type structure.  
  With the above-noted prior art and problems in mind. it is an object of the present invention to provide an extension or expanding kit for use upon a convenetional rowboat or dinghy which extends the size of the boat and thereby increases its stability and carrying capacity.  
  It is another object of the present invention to provide an expanding unit for a dinghy or small rowboat which not only increases the carrying capacity but also includes means secured to the gunwales to stabilize the extension means and provide some weather protection.  
  Yet another object of the present invention is to provide an attachment for use on a dinghy or small boat which increases the size of the boat. provides some weather protection by adding a short fore deck and includes a windshield. The unit may be readily detached from the boat and the two portions may be thus transported on top of an automobile or the like.  
  Still a further object of the present invention is to provide means for securing an extension or expandible section to an open boat hull. The fastening means includes a rigid portion which extends beneath the hull of a boat and in combination with the aft extension and the side rail portion extending along the gunwales forms a rigid loop completely surrounding the main hull of the boat. This rigid loop provides an extremely secure addition to the boat itself and further provides a mounting means for lifting wings or the like.  
  Yet a further object of the present invention is to use the portion of the fastening means which extends beneath the hull of the boat as a base and supporting means for an enlarged supporting ski which extends substantially the length of the hull.  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view showing the basic boat hull in phantom with the inventive extension which provides additional load carrying capacity and stability.  
  FIG. 2 is a section through the gunwale of the boat showing one means of interlocking the extension with the gunwale and simultaneously providing additional flotation.  
  FIG. 3 is an isometric view showing the inventive extension in position upon the hull of a boat.  
  FIG. 4 is a sectional view taken along lines 44 of FIG. 6 showing means of interconnecting the extension and the gunwale of the boat.  
  FIG. 5 is a section taken along line 55 showing the interconnection which may be used with certain hull structures.  
  FIG. 6 is a side elevational view of another embodiment of the invention wherein a rigid element extends beneath the bottom of the hull and forms a complete rigid loop around the boat when used in connection with the extension.  
  FIG. 7 is a section taken along line 7-7 of FIG. 6. FIG. 8 is an enlarged view of the hydrofoil type wing as seen along line 8-8 of FIG. 6.  
 DETAILED DESCRIPTION OF THE DRAWINGS As seen in FIG. I, the basic hull 2, shown in phantom. not being an integral part of the present invention. is  
 generally seaworthy and very usable for calm water and small loads. The present invention contemplates extending the length of the basic hull by securing a section to the after portion. as well as providing some weather protection by providing a forward deck. thereby making the basic hull a far more universal structure.  
 The addition or extension to the basic hull includes a hollow rear portion 4 having a bottom 6. a front generally planar portion 8 and a rear portion I capable of receiving the mounting of an outboard motor 12. The front portion 8 is designed to fit tightly against the stem 9 of the basic hull and. when bolted there. will form the extension.  
  The top portion of the rear- 4 has interconnected therewith a pair of forwardly extending side elements 13 having an outwardly extending flange I4 and upwardly extending side rails 16. The upwardly extending side rails l&#39;6&#39;and the ledge 14 extend forwardly and are adapted to interlockwith the boat hull. as explained hereinaftersThe forwardly extending portion may terminate at the bow of the boat in a small deck area 18 which will provide some weather protection to a normally open boat. As desired. the side rails 16 can extend smoothly upwardly to terminate in a windshield portion 20 just behind-the deck I8 and may include as a portion thereof side windows 22. As will be readily apparent. the addition of the windshield 20 and the side rails l6,-as wellas the windows 22, enables the operator to utilize a canvas cover. thus increasing his foul weather protection. As an alternate structure. the  
  flanges andside rails may extend forward only a sufficient amount to assure a rigid interlock.  
  Referring now to FIG. 2. it can be seen that in one embodiment the flange 14 of the forwardly extending portion includes as an integral part thereof an optional foam flotation 24 which extends down within the gun- Wale-adjacent thereto and mounting blocks 26 and 28. The flange 14 extends out over the existing superstructure 30, which includes an integral bead 32 along its upper edge. The block 26 abuts the interior of the gunwale and the block 28 is placed in position along the exterior of the gunwale and secured there by means of a screw 34 or other suitable fastener. As is readily apparent. once the block 28 is secured in position and serves to envelope bead 32, the flange 14, as well the rest of the additional structure is locked to the gunwale. Theinterconnection between the reinforcing bead 32 and the side ledge 14 not only serves to provide additional securement for the extension but also serves to increase the rigidity and strengthen the gunwale itself.  
  As seen in FIG. 3, the stern 9 of the boat 2 is slightly larger than the extension 4 so that the extension will not create excessive drag upon the movement of the hull itslef. Further to be seen in FIG. 3, the lateral extension or flange 14 forms a unit which ties the rearward extension 4 to the main hull portion 2.  
  It is to be understood that the gunwale structure. as seen in FIG. 2, is representative of only one style of gunwale and reinforcing bead combination on the market. As seen in FIGS. 4 and 5, the gunwale may terminate in an outwardly rolled loop or roll 42. in which case the transverse horizontal member or flange 14 may have a complementary loop 44. The loop or roll 44 interconnects with the loop 42, thereby eliminating the need for the clamping blocks and mechanical fastening. At portions where the transom is relatively III straight and if the upper portion. i.e.. the transverse member or flange l4 and the side rails 16. are not made in a single unit. the transverse member I4 may terminate in a more complete loop 46 which locks beneath the loop 42 of the gunwale 40.  
  As seen in FIG. 6. the rear extension 68. as well as the side rails 54.56 and forward decking 60. can be linked together as&#39;a single unit by means of a rigid member extending beneath the entire length of the hull. As seen in this figure. the hull. denoted 52. supports the side rails 54,56 which extend forward to include side windows 58. A front section 60 includes a foredeck 62 and a windshield 64. The aft section 66 terminates just forward of the transom of the hull 52 and includes as an integral part thereof the rear side rail 54 and the downwardly extending hollow portion 68. The utilization of three sections along the side 54,56 and 58. as described hereinabove and depicted in this Figure enables the basic invention to be applied to boats of different lengths without the necessity of forming new molds. The central section 56 may be varied in length to accommodate various boat lengths without modification of the basic fore and aft sections. It is to be understood that the three sections 54.56.58 will be interlocked in an appropriate fashion to assure rigidity and vibration free installation.  
  It is to be noted that. as seen in this Figure. section lines 4-4 and 5--5 denote two possible areas where different interlocking structures. as shown in FIGS. 4 and 5, could be utilized. The central section ofthe transom below section 54 is sufficiently straight that it could include the complete wrap as shown in FIG. 5. It is necessary to have a less complete wrap in the bow section of the hull to permit the adding or removal of this section as the necessary addition to or removal requiring an outward flexure of portion 44.  
  A rigid member 70 extends from a fastening point 72 upon the deck downwardly passing beneath the hull of the boat along the keel line rearwardly to its aftermost position 74 where it is secured to the rear section 68. The rigid member includes spacing elements 76 and 78 which are adjustable in length to assure that there is a solid interconnection between the keel and the rigid member so the elements will serve as integral members.  
  Included on the rigid member 70 are a plurality of wings 80. As best seen in FIGS. 7 and 8, the wings 80 extend outwardly. essentially parallel to the bottom of the hull 52, and provide lift when the boat is in motion moving the hull up out of the water. greatly reducing the drag. As seen in FIG. 6, the regular waterline. i.e.. that at which the boat would ride without the wings. is denoted as RWL and the waterline achieved when underway with the utilization of the wings is designated WWL. The wings 80 are secured to the rigid member 70 by means of bolts 82 passing through flanges upon the wings themselves. as well as through the rigid member 70. If the rigid member 70 is in the form of a pipe the inner surfaces of the wings 80 would be made to conform for the utmost rigidity.  
  As shown in phantom in FIGS. 6 and 7, the rigid element 70 may also serve as a supporting element for a large ski element 90. The ski would be in the form of a wide solid element having the general profile configuration of a snow or water ski and be utilized to lift the hull and reduce drag. The ski would be secured to both the rigid element 70 and wings 80 by means of bolts or the like which would pass through bores 92.93 and may well be countersunk.  
  Attention is directed to FIG. 7 wherein the aftermost portion of the extension is reduced in depth as at 96 to accommodate an outboard engine having a standard shaft length. The stem 53 of the main hull portion is retained at its normal height for safety. If the extension 68 does not include a lowered stern. a motor having a long shaft will be utilized.  
  Thus it can be seen that the present invention provides a ready additon to a small boat. greatly increasing its boat capacity as well as its stability and ability to handle rough weather.  
  The embodiments of the invention in which a particular property or pri iledge is claimed are defined as follows:  
  1. An attachment for extending the size and loadcarrying capacity of a boat having a substantially flat transom and a reinforcing means at the gunwale comprising:  
 a generally hollow extension element including a bottom a forward wall. a rear wall and a pair of interconnecting sides forming an upwardly opening main body which generally continues the lines of the hull of the boat.  
 means detachably securing the extension element with said forward wall contiguous with the transom of the boat. and  
 a forwardly extending portion integral with the extension element including a deck portion and side rails along the gunwale of the boat. said rails mechanically interlocking with the gunwales.  
  2. Apparatus as in claim 1 and further including a windshield portion extending upwardly from and interconnected with the side rails and deck portion.  
  3. Apparatus as in claim 1 and further including flotation means integral with said deck portion and side rails.  
  4. Apparatus as in claim 1 wherein the extension element includes means for mounting an outboard motor.  
  5. Apparatus as in claim I wherein the securing means includes a rigid elongated element having its first end secured to the extension element and extending forwardly beneath the boat adjacent the keel thereof having its second end secured to the bow of the boat.  
  6. Apparatus as in claim 5 wherein the elongated element includes outwardly extending wings which serve to lift the boat and reduce drag when under way.  
  7. Apparatus as in claim 1 wherein the side rails and deck are formed in sections which are telescopically fitted onto the reinforcing means upon the gunwale.