Portable Knockdown Boat Hoist

Abstract

a portable knockdown boat hoist for lifting boat from boat trailer or other resting location. Comprising of two A-frame structures positioned over the bow and stern of the boat. Each A-frame unit consists of two splayed legs on each side of the boat connected by a crossmember running over the top of the boat. At each side of the boat attached to one leg is a winch with a block and pulley connected by cable to the winch. Cranking up on the winch pulls up a lifting strap running underneath the hull of the boat, which in turn lifts the boat. The A-frame structures are comprised of tube sections that insert one end into the next section. A-frame units can be disassembled for transporting to boat location for lifting.

Claims

1. A portable knockdown boat hoist comprising: Two identical A-frame structures each elongated on the top with a crossmember Each said A-frame structure having a pair of splayed legs with each said pair of splayed legs secured by tension chains. Each said A-frame structure has a winch and cable attached to one leg on each side of said A-frame structure. With each said winch and cable engaging a pulley system. Each said pulley system is attached to the end of the lifting strap. Whereby said A-frame structures are positioned over the bow and stern of a boat with said lifting straps running under the hull of said boat. Activation of said winches and cable acting upon the said pulley system in turn lifts said boat.

2. A portable boat hoist as set forth in claim one wherein: Each said A-frame structure is comprised of three segments with said segments assembled by slip fit ends. Each said slip fit end is held in place by self locking pins. Whereby said A-frame structures can be disassembled into portable units.

3. A portable boat hoist as set forth in claim one wherein: each said A-frame structure has one winch and pulley assembly attached to each side of both A-frame structures. Said four individual winch and pulley assemblies act upon and lift each end of two lifting straps running under bow and stern of boat. Whereby acting independently said winches allow for rotating and tilting of boat to produce level position upon lifting.

4. A portable boat hoist as set forth in claim one wherein: A single said A-frame structure can be made more narrow by removing said male crossmember segment from the top. A single said A-frame structure can be made shorter by removing said bottom leg segments from each leg. Whereby said single smaller A-frame structure can be used to lift objects smaller than a boat, such as an outboard motor.

Description

DRAWINGSFIGURES

[0025] FIG. 1 is a side view of embodiment 1 showing boat in a lifted position.

[0026] FIG. 2 is a front view of embodiment 1 showing boat in a lifted position.

[0027] FIG. 3 is an elevated isometric exploded view of embodiment 1.

[0028] FIG. 4 is a perspective view of the winch and cable with pulley system attached to leg of A-frame structure.

[0029] FIG. 5 is a perspective exploded view of the A-frame shoulder section with attached legs and crossmembers.

[0030] FIG. 6 is a side perspective view of a second embodiment of the portable boat hoist made in accordance with the specifications and operation of the first embodiment.

DRAWINGSREFERENCE NUMERALS

[0031] 10 hoist apparatus [0032] 12 A-frame structure leg [0033] 14 crossmember section [0034] 16 shoulder section [0035] 18 winch [0036] 20 elongated A-frame structure [0037] 22 winch cable [0038] 24 snatch block pulley [0039] 26 eyehook [0040] 28 lifting strap [0041] 30 cable hook [0042] 32 top leg segment [0043] 34 leg strut [0044] 36 scaffolding locking pin [0045] 38 middle leg segments [0046] 40 male insert [0047] 42 bottom leg segments [0048] 44 male crossmember segment [0049] 46 female crossmember segment [0050] 48 tension chain triangle [0051] 50 tension chain middle segment [0052] 60 tension chain assembly

DETAILED DESCRIPTION

First Embodiment

FIGS. 1 and 2

[0053] Referring now to the drawings, the first embodiment is shown in FIGS. 1 and 2, generally at 10 comprising two identical vertical A-frame structures transversely disposed indicated by 20. In FIG. 1, the A-frame structures 20 are deployed at the bow and stern of boat A.

[0054] Each A-frame structure includes a pair of splayed legs 12 on each side. Two parallel crossmembers 14 travel across and over the boat A attaching to a shoulder section 16 that attach to the top of the leg sections 12.

[0055] FIG. 3 shows the assembly of a single A-frame structure. Each leg section 12 is comprised of three segments. The top leg segment 32 inserts over a strut 34 welded to the shoulder section 16 at a 12 degree angle outward away from the boat and a 12 angle forward for the front leg and 12 angle rearward for the back leg. FIG. 5 displays the top leg section 32 which has a slip fit tolerance over the strut 34 that is held in place with a scaffolding lock pin 36 passing through an aligned hole in both the top leg section 32 and the strut 34. FIG. 3 shows the middle leg segment 38 with the winch 18 attached to the top portion. The middle leg segment 38 has a coupling insert 40 welded onto it. The coupling insert 40 fits into the bottom of top leg segment 32 and is held in place with a scaffolding lock pin 36 which is inserted to aligned holes on the bottom of 32 and 40 as shown in FIG. 3. Bottom leg segment 42 also has a coupling insert 40 welded onto its top. In a similar fashion, coupling insert 40 shown on the top of segment 42 is inserted into the bottom of 38 and held in place with a scaffolding lock pin 36.

[0056] FIG. 3 shows the parallel crossmembers on top of one of the A-frame structures comprised of two segments. Male crossmember segment 44 has a coupling insert 40 welded onto the end. This coupling insert 40 attaches to the female crossmember segment 46 and is held in place with a scaffolding lock pin 36. FIG. 5 shows the ends of the crossmember unit 14 inserted into the shoulder sections 16 as shown which is held in place with a scaffolding lock pin 36.

[0057] FIG. 1 shows a winch 18 attached to the middle leg segment 36 per each side of each A-frame structure 10. The winch 18 has its cable 22 running through a pulley system. The pulley system is comprised of two snatch blocks 24. The first snatch block 24 attached to the cable 22 is attached to an eyebolt 26 on the shoulder section 16. The second snatch block 24 is attached to a lifting strap 28 that runs under the hull of the boat A. Winch cable end is attached to a hook 30 that is attached to the shoulder section 16.

[0058] FIG. 2 shows an eyebolt 44 attached at the bottom of each leg segment 12. To this a tension chain assembly 60 is attached to eyebolt 44. The tension chain assembly 60 is comprised of two triangular chain segments 48. Two ends of the triangle 48 are attached to the eyebolts 44. The third conner of the triangle 48 attaches to a chain middle segment 50 using two chain hooks 52 attached to each end of the middle chain segment 50.

Operation

[0059] By these above structural arrangements, the A-frame structures 16 are positioned over the bow and stern of the boat A. The lifting straps 28 are attached to the snatch block 24 and passed under the hull of the boat A. The winches on each side of the A-frame structure reel in the cable 22 raising each end of the lifting strap 28 at a two to one ratio. The lifting strap 28 lifts the hull of the boat. The four winches 18 are operated independently of each other, allowing the boat to be raised in a level manner even if the ground underneath the boat is not level.

[0060] The weight of the boat is held up by the leg sections 12. The leg sections 12 are kept from falling inwards at the top by attaching to shoulder sections 16 which is positioned by crossmember section 14. The leg sections 12 are kept from splaying outward by tension chain assembly 60 attached to the bottom of the legs 12. Since the legs 12 are wider at their base, this allows for clearance of a boat trailer to be pulled out from underneath the boat and positioned back under the boat as required.

Additional Embodiment

FIG. 6

[0061] An additional embodiment is shown in FIG. 6 where a single A-frame structure 20 is positioned standing over a Marine outboard motor B. The width of the A-frame structure 20 is reduced to half by using only the female crossmember section 46 and not inserting male crossmember section 44. Lifting strap 28 is secured around outboard motor B with ends of lifting strap 28 both connected to snatch blocks 24 on each side of the single A-frame structure. In this way, when winch 18 is cranked in, the outboard motor is lifted off the boat. The removal of the outboard motor from the boat is useful for replacing or doing maintenance on the outboard motor.

[0062] The embodiments been shown and described herein are conceived to be the most practical and preferred embodiments. However, it is recognized that departures may be made therefore within the scope of these embodiments, which therefore are not to be limited to the details disclosed herein, but are to be afforded the full scope of the claims so as to embrace any and all equivalent apparatus and articles.