Abstract: A lock device has a pair of locking elements with internal locking teeth, a pair of shafts with external locking teeth configured for meshing engagement with the internal locking teeth, a pair of housing portions configured to receive and retain the respective shafts, and a case configured to receive the locking elements. The locking elements are permitted to undergo sliding movement within the case between first and second states of the lock device. In the first state, the internal locking teeth of the locking elements are disposed in respective meshing engagement with the external locking teeth of the shafts so that the case cannot undergo rotational movement relative to the shafts. In the second state, the internal locking teeth of the locking elements are not disposed in meshing engagement with the external locking teeth of the shafts so that the case can undergo rotational movement relative to the shafts.

Abstract: A boat trailer stair system is provided for facilitating access to a boat supported by a trailer. The system includes an A-frame configured stairway having interconnected forward and rearward frame sections that angularly diverge from top to bottom for positioning adjacent to a vessel supported on the boat trailer. The upper ends of the frame sections are interconnected and the diverging lower ends are fastened to longitudinally spaced apart locations on a longitudinal beam of the boat trailer. At least one of the frame sections supports a plurality of steps that ascend the frame section adjacent to the hull of a supported vessel. A pair of interconnected stairways may be mounted to the trailer on respective sides of the supported boat.

Abstract: Ladders, ladder components and related methods are provided including embodiments of a hinge that may be used in a combination ladder. In one embodiment, a hinge mechanism includes a first hinge assembly and a second hinge assembly. The first and second hinge assemblies are coupled together for relative rotation about a defined axis. An adjustment mechanism enables the two hinge assemblies to be selectively locked or unlocked to prohibit or permit relative rotation, respectively. In one embodiment, the adjustment mechanism includes a lock plate displaceable along a first axis and a retainer displaceable along a second axis. The retainer is configured to hold the lock plate in a disengaged state until a release structure displaces the retainer away from the lock plate. The release structure may be configured to be actuated and displace the retainer upon relative rotation of the hinge assemblies to (or through) a predetermined angular configuration.

Abstract: Disclosed is a movable ladder formed by a structural element composed of a rear part and two sides, the lower part of the vertical structural elements of the ladder terminating in lateral projections in the form of an inverted “U” that provide the ladder with reliable support on the floor. The ladder is characterised in that it is provided with two collapsible lateral platforms and four wheels that can be raised or lowered to facilitate the movement of the ladder toward the work area.

Abstract: A portable parallel walking bar assembly is provided which is intended for use in a variety of settings due to the uniquely designed ability to rapidly assemble, disassemble, transport and store the apparatus when not in use. This particular design is made of five lightweight individual parts which may be assembled to form a stable support structure. Two of the segments are each of the parallel bars which in this design are collapsible in length and allow for variation in length. The bars extend to a length of 8.5 feet and collapse to a length of only 4 feet. The remaining three parts of the system are the support stanchions which the horizontal bars attach to for stabilization and their useful intended height of 24 to 40 inches. Each support stanchion consists of a flat cross-member, with beveled edge, which spans the width of the assembled system and provides the base of support. On both ends of each cross-member, a vertical support extends up and is adjustable in height.

Abstract: Ladders and related methods of using and manufacturing stepladders are provided. In one embodiment, a stepladder is provided that comprises a first assembly hingedly coupled with a second assembly. The first assembly has a pair of spaced apart rails pivotally coupled with one or more rungs. The second assembly includes a pair of space apart rails with one or more bracing members extending therebetween. The first assembly and second assembly are configured to be displaced relative one another such that the stepladder is selectively positionable between a first, deployed state and a second, collapsed state. Upon rotation of the two assemblies relative to one another into a stowed condition, components of the second assembly engage undersurfaces of the rungs effecting rotation of at least a portion of each rung relative to the rails of the first assembly.

Abstract: A combined stepladder and work platform assembly is provided. The assembly comprises a top frame having two side rails and footplate, a back frame pivotally attached to the back side of the top frame and having two side rails, and a front frame pivotally attached to the front side of the top frame and having two side rails. Link bars are provided so that they maintain steps horizontal together with the side rails of the front frame. Four braces secure the back frame and front frame with the top frame at a certain angle when the assembly is used as a work platform. The front frame, the top frame and the back frame form a triangular shape while the back frame is parallel to the floor when the assembly is used as a stepladder.

Abstract: The present invention is directed to a ramp insert for insertion between rails and/or rungs of a ramp. An embodiment of the present invention includes a body that may have an adjustable length. The body may include a first section that may include a track portion and a second section that may include a groove portion. The groove portion may be capable of fitting together with the track portion. The first or second section may be capable of slidably moving with respect to the other section via the track portion and the groove portion. The ramp insert may be placed between the rails and/or rungs of the ramp whereby the ramp insert may be adjusted to various lengths. Since the ramp insert may be adjusted to various lengths, the ramp insert may fit many different kinds of ramps having various widths.

Abstract: The present invention is directed to a ramp insert for insertion between rails and/or rungs of a ramp. An embodiment of the present invention includes a body that may have an adjustable length. The body may include a first section that may include a track portion and a second section that may include a groove portion. The groove portion may be capable of fitting together with the track portion. The first or second section may be capable of slidably moving with respect to the other section via the track portion and the groove portion. The ramp insert may be placed between the rails and/or rungs of the ramp whereby the ramp insert may be adjusted to various lengths. Since the ramp insert may be adjusted to various lengths, the ramp insert may fit many different kinds of ramps having various widths.

Abstract: A convertible ladder and scaffold assembly includes a plurality of uprights and a plurality of beams each extending from one of the uprights. A plurality of hinges each hingedly connect one of the uprights to one of the beams about a rotational axis (AR) to provide an assembly having ladder, scaffold, push-cart, and storage configurations. Each of the hinges defines catches and present a stop releasably engaging catches for preventing rotation about the rotational axis (AR). At least one lever bar releasably engages a plurality of the stops for simultaneously releasing a plurality of the stops from engaging catches. Each of the lever bars have a plurality of lever sections for providing leverage to disengage the stops from the catches. Each of the lever bars has a grip section interconnecting the lever sections for simultaneously releasing a plurality of the stops from engaging the catches.

Abstract: A ladder having platform steps, the ladder being convertible between a deployed position for supporting a person or other load, to a storage, scaffold, or ramp position in which the steps lie in a generally planar arrangement. When deployed, the ladder steps remain parallel to each other and form a series of parallelograms with the rails of the ladder. The ladder is also capable of being locked or secured at various angles of deployment. The ladder further includes receivers to selectively receive accessories such as wheels, hooks, handles, or pads. The addition of accessories such as wheels allows the ladder in the storage position to be used as a creeper, dolly, or cart.

Abstract: A convertible ladder and scaffold assembly includes a plurality of uprights and a plurality of beams each extending from one of the uprights. A plurality of hinges each hingedly connect one of the uprights to one of the beams about a rotational axis (AR) to provide an assembly having ladder, scaffold, push-cart, and storage configurations. Each of the hinges defines catches and present a stop releasably engaging catches for preventing rotation about the rotational axis (AR). At least one lever bar releasably engages a plurality of the stops for simultaneously releasing a plurality of the stops from engaging catches. Each of the lever bars have a plurality of lever sections for providing leverage to disengage the stops from the catches. Each of the lever bars has a grip section interconnecting the lever sections for simultaneously releasing a plurality of the stops from engaging the catches.

Abstract: A deck deployment system is adapted to facilitate transfer of personnel between spaced elevations. The deck deployment system includes a deck defining a substantially flat and continuous deck surface for supporting personnel. A convertible stairway is hinged to the deck and adapted for movement between a stowed condition and a deployed condition. The convertible stairway includes an adjustable frame assembly and a series of articulating horizontally-disposed foot treads carried by the frame assembly. The foot treads remain substantially horizontal upon movement of the stairway between the stowed condition and the deployed condition. When the stairway is in the stowed condition, the foot treads integrate with the deck to form a substantially flat and continuous portion of the deck surface. When the stairway is in the deployed condition, the foot treads cooperate to form steps extending from the deck to an elevation spaced from the deck surface.

Abstract: The present invention is to provide a new multi-functional collapsible platform ladder of H shape, comprises a shelf rack, a pair telescopic ladders and a fixing framework, wherein the shelf rack are abutted and linked by a pair platform decks, and has hanger disposed at each distal outer ends thereof; the pair telescopic ladders are juxtaposed at each end of the shelf rack respectively with hanger of the shelf rack hooking on desired rung thereof; and the fixing framework comprises a pair foldable scaffolds, a pair joists and two pair tubular holders, which has a caster disposed thereof. By all foregoing parts, it can be transformed into H-shaped, ?-shaped or single telescopic ladder with multiple functions and features in height adjustment and collapsibility to achieve effects of easy transportation and saving storing space.

Abstract: A ladder having a first ladder section, a second ladder section, an adjustable hinge mechanism, an engagement indicator and a static hinge mechanism. The adjustable hinge mechanism is mounted with respect to the first ladder and the second ladder so that the adjustable hinge mechanism is moveable between an engaged position and a disengaged position. The static hinge mechanism enables the first and second ladder sections to be maintained in a stationary position with respect to each other.

Abstract: Disclosed is a sensing and warning system for ladder load composed of sending means, a recording and calculation device, and an alarm for detecting, recording and evaluating the ladder load, and sending an alarm signal in case the ladder is suffering from an overload so as to warn the user a dangerous state which should be evaded.

Abstract: A length-adjustable ladder functioning as a telescopic lean-to ladder, a free-standing stepladder, and as a platform is described. The ladder includes stringers, ladder rungs fastened between the stringers, and supports connected to the stringers. The supports can be length-adjusted in a stepless manner. The supports can be swung in and arrested on the outer longitudinal sides of the stringers. A floor board assembly formed of two panel halves corresponding to a length of the ladder and has hinges is disposed on the two panel halves. The two panel halves each have a longitudinal side fastened, in an articulated manner on the ladder rungs by the hinges. Arresting elements are provided. Each of the arresting elements run through one of the two panel halves. The two panel halves are movable into a swung-up panel position wherein the two panel halves are arrested by the arresting elements.

Abstract: A length-adjustable ladder functioning as a telescopic lean-to ladder, a free-standing stepladder, and as a platform is described. The ladder includes stringers, ladder rungs fastened between the stringers, and supports connected to the stringers. The supports can be length-adjusted in a stepless manner. The supports can be swung in and arrested on the outer longitudinal sides of the stringers. A floor board assembly formed of two panel halves corresponding to a length of the ladder and has hinges is disposed on the two panel halves. The two panel halves each have a longitudinal side fastened, in an articulated manner on the ladder rungs by the hinges. Arresting elements are provided. Each of the arresting elements run through one of the two panel halves. The two panel halves are movable into a swung-up panel position wherein the two panel halves are arrested by the arresting elements.

Abstract: A lift apparatus includes a superstructure frame support, a riser, and an articulated parallelogram boom assembly operatively connected between the superstructure frame support and the riser. The articulated parallelogram boom assembly includes a floating frame, a lower parallelogram boom assembly operationally connected between the superstructure frame support and the floating frame, an upper parallelogram boom assembly operationally connected between the floating frame and the riser, and a lift mechanism for raising and lowering the articulated parallelogram boom assembly. The lower parallelogram boom assembly, the upper parallelogram boom assembly, and the lift mechanism are formed such that the maximum extension height of the articulated parallelogram boom assembly is increased without an increase in the height of the articulated parallelogram boom assembly when lowered.

Abstract: The aerial work platform includes a support frame, wheels rotatably attached to the support frame, and an electric motor rotatably driving at least one of the wheels. A boom having a first end is pivotably mounted to the support frame, and a fluid motor raises and lowers the boom with respect to the support frame. A work platform is supported by a second end of the boom. A battery pack supplies power to the electric motor. A first support structure, for supporting an auxiliary power plant that supplements power supplied by said battery pack, removably attaches to the support frame.

Abstract: A trailer personnel lift (20) with a level-sensing system (69). The level-sensing system (69) provides information to a level-indicator display (72) that indicates which outriggers (34) of the trailer personnel lift (20) need to be lowered. Upon lowering of the designated outriggers (34), the signal for the outrigger (34) changes so as to indicate that the outrigger (34) no longer needs lowering. The outriggers (34) are capable of locking into at least three positions, a first position (40A) in which the outrigger (34) extends substantially horizontal to the surface upon which the personnel lift (20) is to be located, a second position (48A) in which the outrigger (34) extends substantially vertically from the base, and a third position (46A) that is intermediate of the first and second positions, the third position being selected so that the outriggers (34) may be stabilized in the third position (46A) on an upward slope.

Abstract: An articulated aerial platform system having a lift assembly including an upper parallelogram riser and a lower parallelogram riser. The upper and lower risers are raised and lowered by a single riser cylinder mounted between a base of the system and the upper riser. Relative pivoting motion of the upper and lower risers is controlled by a timing link interconnecting the upper and lower risers. A work platform mounted at the end of a jib pivotally connected to a telescoping boom pivotally connected to the upper riser is leveled for boom motion by operation of a master cylinder and slave cylinder arrangement. The slave cylinder is disposed in a generally vertical position. A jib cylinder actuating motion of the jib is connected across the diagonal of the jib.

Abstract: A lift assembly includes a work platform pivotally mounted on the end of a boom for rotation through 270.degree. around a vertical post on the outer end of the boom. Rotation of the platform is effected manually by an operator on the platform, who also controls the location of the platform with respect to a truck or trailer carrying the lift assembly. A foot operated latch mechanism on the platform retains the platform in one position on the outer end of the boom.

Abstract: A clamshell cage assembly is provided for use in conjunction with a portable personnel lift. The personnel lift may be either a jib boom lift or a lift having a multi-sectional telescoping mast. The clamshell cage assembly has an upper and mid-level safety rail, portions of which pivot to a raised position which facilitates easy entry into the cage wherein the user does not have to stoop or use either hand to hold the cage open. The movable section of safety rail is then pulled downwardly by the user once he has entered the cage.

Abstract: A portable work platform for use in the construction trade which includes a pair of side rails interconnected by a plurality of crossbars and supported by pivotal legs connected to the rails. Disposable edge runners are attached along the upper surface of each rail to protect the rails and crossbars from damage caused by cutting and machining material on the platform surface. In addition, the cross-bars are of a square cross-section to enable workpieces and tools to be clamped to the bars for support.

Abstract: A collapsible ladder having vertical and horizontal ladder parts has a stepboard detachably mounted on the horizontal ladder part. The stepboard has a width which is less than or equal to the separation between uprights of the horizontal ladder part and retaining members for detachably securing the stepboard to the rungs of the horizontal ladder part.

Abstract: A ladder joint includes a pivot, a first base plate mounted on the pivot and connected to a first side rail section of one side rail of a ladder, a second base plate mounted on the pivot and connected to a second side rail section of the side rail, a spring-supported lever pivoted to the pivot, a lock bolt inserted through an eccentric hole on the second base plate and controlled by the lever to engage into either of a series of eccentric holes on the first base plate.

Abstract: A combination scaffold ladder device having a scaffold portion which is formed by a prop positioned above a pair of ladder side members, and is connected to the sides by connecting means which include a top step and a pair of extensible spreaders. The parallel ladder side members each contain at least one indentation, and are joined together by a plurality of ladder steps with two of the steps being partial in nature. The ladder structure and the prop in the horizontal position is supported by versatile support members that are attached near the top of the versatile support member housings to the parallel ladder side members by a plurality of pivotable joint pins and locked into position by a further plurality of extensible spreaders.

Abstract: An assembly including several ladder sections positionable in several different ladder use positions, wherein intermeshable teeth elements can be cam locked selectively into such positions, and further including stabilizer bars at the ladder section ends for stable engagement with a supporting surface.

Abstract: A combination folding ladder and height adjustable scaffold, comprises (a) a first assembly including a first leg and a second leg, each formed by an outer and inner telescoping member, and outer and inner rungs which connect the outer and inner telescoping members in substantially parallel, spaced apart relation; (b) a second assembly including a third leg and a fourth leg, each formed by an outer and inner telescoping member, and outer and inner rungs which connect the outer and inner telescoping legs of the third and fourth legs in substantially parallel, spaced apart relation; (c) positioning joints removably secured to upper ends of the for pivotally securing the first and second assemblies together; (d) a height adjustment assembly for varying the heights of the legs; and (e) a scaffold platform for use with the combination when the positioning joints are removed from the legs and the first and second assemblies are separated, the scaffold platform including a flat rectangular board, U-shaped supports a

Abstract: A folding ladder comprising of four straight sections each consisting of two uprights and four rungs equally spaced. The sections are connected with insulating hinged joints which can be tightened immovable or loosened movable by means of a lever handle thus allowing the adjustment of the ladder into various configurations.

Abstract: The invention is an adjustable folding ladder that can be easily altered in its length and shape to adjust to the proper working height and angles for the user. With the fiber glass nylon hinges, the ladder is insulated to prevent the user from electrical shocks in the event the ladder comes into contact with electrical wiring.

Abstract: The present invention discloses a multipurpose ladder, and comprises four section-ladders; four pivot joint device provided between section-ladders, respectively, for connection but at least one pivot joint device being separable. Said pivot joint devices are available for bending or folding. So that, the multipurpose ladder can be change into a climbing ladder, horse ladder, frame ladder and right-angled ladder.

Abstract: A collapsible frame of a general ladder shape having elongated side rails connected by transverse support members. The frame defines an inverted U-shaped frame when in its unfolded operative position. A winch and pulleys attached to the frame are used for lifting or lowering a load. One downwardly extending leg of the frame has telescoping legs and wheels to provide for height adjustment and use as a hand truck for transporting a load. The second leg of the frame may be connected to a ladder bracket and ladder for lifting a load to an elevated location.

Abstract: This invention relates to a detachable top to be used with foldup ladders of the type described in co-pending applications Ser. Nos. 06/341,830; 06/492,487; and 06/537,276. Also, this top can be used with the slidable ladder described in U.S. Pat. No. 4,429,766. This ladder can be converted into many structures such as a workbench, table or step ladder. The top comprises a rectangular main portion and a narrower extending section. The main portion fits over and around the rails of the ladder (after conversion to a workbench) and the narrower extending section fits inside the rails but on substantially the same plane as the main portion.

Abstract: A portable folding ladder comprising a plurality of U-shaped modules having a rung and two vertical portions, the modules movable connected to each other, and when opened becoming progressively narrower as they approach the top of the ladder, when folded the narrower modules fitting inside of the next wider modules and locking means to lock the modules in a rigid manner when the ladder is extended and open.

Abstract: A ladder attachment for securement to a ladder leg which can function as a ladder standoff, ladder leg extension or roof ridge hook. The ladder standoff arrangement permits the ladder to be supported a predetermined distance from a wall, enables the ladder to be used as a scaffold, or provides a support for a work table or sawhorse.The attachment comprises a channel having an adjustable web and sidewalls with a reversible angle secured to one sidewall which cooperates with biasing means passing through the channel web and a ladder stile to frictionally lock an elongated member passing through holes formed in the sidewalls as a standoff or roof ridge hook or to frictionally lock an elongated member adjacent a ladder leg as an extension thereof.

Abstract: Structures including a platform and a slide located adjacent to the platform which are primarily useful for play purposes can be constructed so as to fold into an essentially small, flat configuration for storage and shipment purposes. Such structures are constructed utilizing a support including two normally upright sections connected by a plurality of links or link-type structures, one of which extends between the sections and serves as the platform. The links or link-type structures used are connected to the sections so that the sections can be manipulated between an open position in which they are spaced from one another and a folded position in which the sections are adjacent to one another.

Abstract: A convertible ladder is provided which can be set up as an extension ladder, a step ladder or a trestle. A pair of leg assemblies each have a pair of sides connected by a plurality of rungs. Each leg assembly has regularly spaced hooks along its length which engage with the end lugs of a plank member. The plank member has arms provided with lugs which engage another pair of hooks on each leg assembly to form a trestle. The leg assemblies are also provided with a pair of upturned hook lugs which engage a rung of the other leg to form an extension ladder. In the step ladder configuration, the leg assemblies are maintained at maximum angular relationship by means of ties pivotally connected to one leg assembly with openings to engage pins on the other leg assembly.

Abstract: A ladder kit comprises a plurality of parts from which a ladder may be constructed. The parts of the kit may be selected and assembled in a number of ways, resulting in various types of ladder structures. The main components of the assembled ladders include elongated tubular side rail sections and rectangular frame sections. The frame sections fasten the side rail sections into coplanar pairs and form the rungs of the ladder.