Abstract: A ladder moving device utilizes an A-frame ladder with a plurality of wheels disposed under each leg, each of which are in mechanical communication to a hand crank. The hand crank is disposed adjacent the upper end of the ladder. Each wheel has a locking mechanism.

Abstract: The present disclosure relates generally to personnel lift vehicles that include a carriage, a telescoping lift and a load carrying frame. The telescoping lift is connected to a rear portion of the carriage and the load carrying frame is connected to and extends forward from the telescoping lift. The load carrying frame includes a bottom portion that provides an operator platform that is disposed at a central portion of the carriage between a front portion and the rear portion of the carriage. The configuration of the disclosed personnel lift vehicle provides an integral solution for counterweight requirements for the carriage while reducing the overall driving space required for the vehicle.

Abstract: A lift device includes a base, a retractable lift mechanism, a work platform, and a lift controller. The retractable lift mechanism is moveable between an extended position and a retracted position. The work platform is configured to support a load and is coupled to and supported by the retractable lift mechanism. The linear actuator is configured to selectively move the retractable lift mechanism between the extended position and the retracted position. The linear actuator has an electric motor and an electromagnetic brake. The lift controller is in communication with the linear actuator and is configured to determine the load supported by the work platform based on the actuator force applied to the work platform and the height of the work platform.

Abstract: A tubular transfer system is disclosed which includes a trough coupled between a pair of lifting apparatus, a base member coupled to each of the pair of lifting apparatus, a first adjustment device disposed on the pair of lifting apparatus for adjusting a presentation angle of the trough, and a second adjustment device coupled to the base member and a portion of each of the pair of lifting apparatus for adjusting a presentation height of the trough.

Abstract: The present invention relates to the field of engineering mechanics and more particularly, relates to an engineering work vehicle, and most particularly, relates to a vehicle with a low gravity center and aerial work platform. The vehicle includes a vehicle frame, a power system, a fuel tank, and a hydraulic tank all of which are mounted at a side of the frame. Correspondingly, the embodiment of the invention also provides an aerial work platform which provides better off-road performance and grade-ability, can work in complicated environment, and owns a longer horizontal reach and larger working range. Moreover, maintenance and repair cost is decreased, lifetime is extended, integrity is higher and appearance looks better.

Abstract: The present application includes an assembly for transporting luggage including a carrying member configured to releasably couple the luggage to a traveler around the core portion of the body. The carrying member coupled to a portion of the apparel and to the luggage handle. Loads exerted by the weight of the luggage are placed over the lower body. The method includes the steps of obtaining a carrying member and attaching it to a traveler, followed by attaching the luggage to the carrying member. The traveler may remove or adjust as necessary.

Abstract: The 3 in 1 ladder, dolly, and seating system is a portable, device that can function as a set of stairs, a ladder, a seating area, and a cargo dolly. It is a four wheeled dolly, or a two-handle hand truck with two wheels in front, and can extend to become a ladder or various types of stairs, including steps for sitting. It is constructed from durable aluminum, or another appropriate material. The device can convert into a set of stairs with removable guardrails, or a smaller set of stairs that can be used as seating with foldable backrests. It can be manufactured with an umbrella holder and an optional canopy tent.

Abstract: A motorized wheel system with wireless remote for portable support structure such as ladders and scaffolds to enable a user to relocate the ladder without dismounting by attaching wheels to the portable structure's legs wherein the wheels are remotely controllable. The motorized wheel system with a remote control mechanism comprises a remote motorized wheel device associated with each leg, each having a power supply for driving a motor and a receiver that is in radio communication with a transmitter on a remote control mechanism used to remotely engage the power supply and steer the wheels.

Abstract: A mobile tower drive system for efficiently attaching a removable drive system to a scaffolding unit and driving the scaffolding unit from the work platform. The mobile tower drive system generally includes a lower unit adapted to be secured to a lower end of a scaffolding unit, wherein the lower unit has a wheel to operably engage a floor surface and move between an engaged and disengaged position. The lower unit removably attaches to an upper unit, wherein the upper unit is secured relative the upper frame of the scaffolding unit. Both, the lower unit and the upper unit employ coaxial drives for turning and driving the wheel. The coaxial drive also is used to brake the wheel. The coaxial drives are generally controlled via manually operable rotational control levers; however automated power sources may be utilized. Also disclosed are swivel locks for the caster wheels of the scaffolding unit.

Abstract: A search line rescue system for use by rescue personnel to facilitate a safe search and rescue mission through an area of low to zero visibility is disclosed. The search line rescue system comprises a search rope having a first end configured to be attachable to a fixed point at an entry point, a central portion with at least one distance marker and a second end. The system further comprises a search device handle with a leading end and a trailing end wherein the search device handle is slidably coupled to the search rope. The search device handle comprises a rigid body, an automatic lock mechanism coupled to the rigid body wherein the automatic lock mechanism comprises a manual lock mechanism release, and at least one tag line attachment anchor. At least one locking directional indicator is securely coupled to the search rope at a desired location, and is configured to releasably engage with the automatic lock search mechanism of the search device handle.

Abstract: A modular ladder comprises a base having a back end and a front end. A vertical support is attachable to the back end of the base. The ladder also includes a stair section assembly comprising a plurality of steps. The stair section assembly has a front end and a back end. The front end of the stair section assembly is attachable to the front end of the base. The back end of the stair section assembly is attachable to the vertical support. The stair section assembly comprises a separate top step, whereby the top step is capable of being attached to the stair section and whereby the attachable nature of separate top step facilitates storing the ladder in a compact container which is smaller than the stair section and top step when placed in an assembled condition. A method of storing the ladder in a compact container is also disclosed.

Abstract: A device is disclosed for changing a suction mouth of a cutter suction dredge of a vessel with cutter ladder. In at least one embodiment, the device includes, comprising a work platform which, as seen in the transverse direction of the vessel, is provided substantially in the middle with an opening, wherein—a support structure is provided which can be fixedly connected to the work platform in a position substantially under the opening, which support structure is adapted to support a suction mouth; —and the work platform with support structure is tiltable around a first, substantially horizontal transverse axis between a substantially horizontal operating position and a high position in which the cutter ladder can be moved upward, which positions are such that the work platform with support structure is movable from its high position to its operating position when the cutter ladder is situated in a high raised position.

Abstract: An anchoring system includes an anchor member to anchor the lifeline and at least one extending unit to extend the anchor member out to a working position beyond (horizontally) and above (vertically) an edge to provide for an overhead anchoring point. The anchoring system preferably further includes a support to which the extending unit is attached. The support immobilizes the overhead anchoring system so that the anchor member remains at the working position (even in the case of a fall by the worker). A method of anchoring a fall protection lifeline for use by a worker working at or beyond an edge includes the steps: elevating an anchor member to position the lifeline above the head of a worker and supporting the anchor member at the working position. The method can also include the step of extending the anchor member to a working position horizontally beyond and above the edge.

Abstract: A portable scaffold moving device for connecting to scaffolding and which provides rotary motion to a drive wheel, to move scaffolding in select directions. The portable scaffold moving device includes a power wheel, rotary driven through a perpendicular or right-angled gear reduction, receiving its rotary force from a drive shaft, and the drive shaft couples with a portable drill, which furnishes the rotational force necessary for driving the drive shaft, and its associated drive wheel. The bracket mechanism supporting the portable drill supports the drill during its delivery of rotary force to the drive shaft, and its wheel, and likewise, pivotally mounts to an outer support sleeve or tube that furnishes steering, to the drive mechanism, and consequentially to the scaffolding, during its power movement.

Abstract: An accessory for a ladder includes a set of wheels that can be attached to the feet of the ladder and a gear mechanism that couples those wheels to an operating handle. The operating handle includes a plurality of sections so it can be reached by a user who is supported on top of the ladder. Operation of the handle rotates the wheels to move the ladder while the user remains in place on the ladder.

Abstract: A light-weight self-propelled scaffold vehicle is guidable through the use of a toggle switch. It is dimensioned and designed to be able to be utilized in small areas and through 30 inch doorways as well as for larger areas.

Abstract: A portable device for connecting to scaffolding and which provides rotary motion to a drive wheel, to move scaffolding in select directions. The device includes a power wheel, rotary driven through a perpendicular or right-angled gear reduction, receiving its rotary force from a drive shaft, and the drive shaft couples with a portable drill, or other tool, that furnishes the rotational force necessary for driving the drive shaft, and its associated drive wheel. The bracket mechanism supporting the portable appliance supports the appliance during its delivery of rotary force to the drive shaft, and its wheel, and likewise, pivotally mounts to an outer support sleeve or tube that furnishes steering, to the drive mechanism, and consequently to the scaffolding, during its power movement. A locking bar affixes a pair of the castors into alignment.

Abstract: A portable device for connecting to scaffolding and which provides rotary motion to a drive wheel, to move scaffolding in select directions. The device includes a power wheel, rotary driven through a perpendicular or right-angled gear reduction, receiving its rotary force from a drive shaft, and the drive shaft couples with a portable drill, or other tool, that furnishes the rotational force necessary for driving the drive shaft, and its associated drive wheel. The bracket mechanism supporting the portable appliance supports the appliance during its delivery of rotary force to the drive shaft, and its wheel, and likewise, pivotally mounts to an outer support sleeve or tube that furnishes steering, to the drive mechanism, and consequently to the scaffolding, during its power movement.

Abstract: What is disclosed is a combined pair of ladders and transportation dolly device. The device includes a first framework having a first and a second end and a second framework having a first and a second extremity. The first extremity of the second framework is pivotally secured to the first end of the first framework about a first pivotal axis. A loading platform is provided for supporting a load. The platform has a first and a second edge. The platform is pivotally secured to the second end of the first framework about a second pivotal axis, the second axis being disposed between the first and the second edges of the platform. A tie bar has a first and second termination with the first termination being pivotally secured to the second edge of the platform about a third pivotal axis. The second termination of the platform is pivotally secured to the second framework about a fourth pivotal axis. The fourth pivotal axis is disposed between the first and the second extremities of the second framework.

Abstract: A step ladder comprising an upright frame and a plurality of wheels on the frame arranged to engage a ground surface. A drive wheel assembly is arranged to drive at least one of the wheels for moving the ladder and being arranged to be controlled by a user positioned on the ladder. A steering wheel assembly for steering at least another one of the wheels and being arranged to be controlled by a user positioned on the ladder. A pulley arrangement of the drive wheel assembly extending from a top portion of the ladder within an interior of the frame to a driven wheel and a drive mechanism coupled to the pulley arrangement at the top portion of the ladder for driving the pulley arrangement.

Abstract: The mobile scaffold vehicle has a motorized base with an upper surface and a first frame member and a second member. The first and second fame members are pivotally mounted near respective opposite ends of the upper surface. The first frame member is movable independently of the second frame member from an inoperative storage position near the upper surface and a generally vertical operative position. The second frame member is movable independently of the first frame member from an inoperative storage position near the upper surface and a generally vertical operative position, so that in their operative positions, the first and second fame members are generally paralel with one another and located near opposite ends of the upper surface. A platform is attachable with the frame members in the operative position and a plurality of anchor arrangements for anchoring the frame members in the operative position, thereby to permit a operator to stand on the platform.

Abstract: A portable device for connecting to scaffolding and which provides rotary motion to a drive wheel, to move scaffolding in select directions. The device includes a power wheel, rotary driven through a perpendicular or right-angled gear reduction, receiving its rotary force from a drive shaft, and the drive shaft couples with a portable drill, or other tool, that furnishes the rotational force necessary for driving the drive shaft, and its associated drive wheel. The bracket mechanism supporting the portable appliance supports the appliance during its delivery of rotary force to the drive shaft, and its wheel, and likewise, pivotally mounts to an outer support sleeve or tube that furnishes steering, to the drive mechanism, and consequently to the scaffolding, during its power movement.

Abstract: A portable device for connecting to scaffolding and which provides rotary motion to a drive wheel, to move scaffolding in select directions. The device includes a power wheel, rotary driven through a perpendicular or right-angled gear reduction, receiving its rotary force from a drive shaft, and the drive shaft couples with a portable drill, or other tool, that furnishes the rotational force necessary for driving the drive shaft, and its associated drive wheel. The bracket mechanism supporting the portable appliance supports the appliance during its delivery of rotary force to the drive shaft, and its wheel, and likewise, pivotally mounts to an outer support sleeve or tube that furnishes steering, to the drive mechanism, and consequently to the scaffolding, during its power movement.

Abstract: A portable stairway for use with standard airport boarding bridges is disclosed. The stairway is easily portable as a standalone unit. The stairway also easily connects to and disconnects from the boarding bridge. The type of releasable connection provided between the stairway and the boarding bridge is secure but allows the stairway and the boarding bridge to pivot vertically with respect to one another. Such a connection allows the stairway to be used when the boarding bridge and stairway are not aligned at exactly the same height. When properly connected to the boarding bridge, the stairway provides a smooth transition between the boarding bridge and the stairway and leads from the outer doorway of the boarding bridge to the airplane parking level. Also, while connected to the boarding bridge, the stairway moves freely with the boarding bridge as it is moved about the airplane parking level to service various airplane parking positions.

Abstract: An attachment assembly provides a secure attachment point for the fall arrest tether lines of safety harnesses of workers on flat roofs, the assembly being movable over the roof as required. The assembly can be used alone, but usually is mounted on a wheeled utility cart as employed by roofers to move materials on the roof, or may be an integral part of such a cart. The assembly has a base frame that is spaced from the roof edge over which the worker may fall. An attachment member for tether lines is mounted on the base frame together with at least two longitudinally spaced surface engaging arm, the arms being located at the frame side nearer to the roof edge. When the assembly is in operative position each arm has its lower end, which usually has teeth, close to the roof surface. A counterweight is mounted on the opposite side of the base frame.

Abstract: A step stool having a front frame member having a bottom end and a rear frame member having a bottom end coupled to the front frame member for pivotable movement about a frame pivot axis between an opened position in which the bottom end of the front frame member is spaced apart from the bottom end of the rear frame member and a collapsed position in which the bottom ends of the front and rear frame members are positioned to lie adjacent to one another and a leg cap including a flange and a flange support fixture coupled to the bottom end of the front frame member to support the flange in a predetermined position relative to the front frame member. A wheel coupled to the flange to rotate about a wheel axis and a floor pad coupled to the leg cap and adapted to rest on a floor underlying the frame and support the wheel in an elevated position above the floor upon movement of the front and rear frame members to the opened position.

Abstract: A universal motorized scaffold truck with a horizontal support frame adapted for removably supporting scaffold or "A" ladders thereon and supported by wheels for lateral movement on a ground surface. A vertically extendable steering mast is provided which is secured at its lower end to the frame and adapted for steering selected of the wheels from the upper end of the mast. An electric motor is mounted on the frame and adapted for driving desired wheels and a switch is provided at the upper end of the mast for selectively engaging the electric motor to drive the truck in either direction. The steering mast is adapted to fold down horizontally for storage on the frame and may be locked into position in its upright position and secured to the scaffold or ladder for security.

Abstract: A scaffold device including a frame having four stanchions, an upper peripheral railing mounted to tops of the stanchions, and a pair of cross brace assemblies mounted between the stanchions. A platform is also mounted between the stanchions. A plurality of drive units each include a housing with a wheel rotatably mounted therein with a motor operatively coupled thereto for rotating the wheels upon the actuation thereof. The housings are each rotatably mounted on a bottom end of one of the stanchions with an associated motor operatively coupled thereto for pivoting the housing and wheel upon the actuation thereof. Also included is a control assembly in communication with the motors for actuating the same.

Abstract: A personnel lift (20) including a three-wheeled transport in which a rear or transport wheel (30) is connected to a lever arm or handle (32) that is designed to raise and lower the transport wheel (30). Pulling the handle (32) downward drops the transport wheel (30) to ground level raising the support legs (34) off the ground. Raising the handle (32) lifts the transport wheel (30) off the ground, dropping the support legs (34) onto the ground. An electric interlock system is utilized to prevent the vertical lift assembly (24) of the personnel lift (20) from being used when the support legs (34) are not on the ground. The electric interlock system includes three switches (89, 104a, 104b), all of which must be closed in order for the aerial work platform (22) to be elevated. Two of the switches (104a, 104b) are operated by the support legs (34). The switches (104a, 104b) in the support legs (34) are closed when the support legs are in full contact with the ground.

Abstract: A personnel lift (20) including a three-wheeled transport in which a rear or transport wheel (30) is connected to a lever arm or handle (32) that is designed to raise and lower the transport wheel (30). Pulling the handle (32) downward drops the transport wheel (30) to ground level raising the support legs (34) off the ground. Raising the handle (32) lifts the transport wheel (30) off the ground, dropping the support legs (34) onto the ground. An electric interlock system is utilized to prevent the vertical lift assembly (24) of the personnel lift (20) from being used when the support legs (34) are not on the ground. The electric interlock system includes three switches (89, 104a, 104b), all of which must be closed in order for the aerial work platform (22) to be elevated. Two of the switches (104a, 104b) are operated by the support legs (34). The switches (104a, 104b) in the support legs (34) are closed when the support legs are in full contact with the ground.

Abstract: A movable working platform comprises a scaffold including a front frame having a pair of support posts, and a pair of front wheels mounted on opposite sides of a lower end of the front frame, a rear frame having a pair of support posts, and a pair of rear wheels mounted on opposite sides of a lower end of the rear frame. A scaffolding platform is disposed between the front and rear. A steering mechanism of the platform includes a steering shaft vertically arranged along the front frame, a handle mounted on an upper end of the steering shaft, and a drive wheel mounted on a lower end of the steering shaft. A drive mechanism of the platform includes a pedal swingably supported by the front frame, a wire member wound on a pulley and reciprocally moved in response to a swinging motion of the pedal, and a one-way clutch for transmitting only a one-way rotation of the pulley to the drive wheel.

Abstract: The present invention relates to a step up device which provides a large stable platform with a hand rail to give the user a safe method of elevation. Older and/or infirm people frequently experience limited movement of their limbs making it difficult to get into bed. To do this an elevation aid is often required. Current stools and step up devices for this purpose are widely available in hospitals but are cumbersome taking up much storage space and are difficult to transport from place to place for use by different patients. This invention provides an improved step-up device which reduces storage space and improves transportation. The present invention provides a large stable platform with a hand rail to provide the user with a safe method of elevation. The hand rail is foldable, and is positioned to provide stability to the platform. The top of the platform is designed with a non-slip surface and a non-skid material is fastened to the legs to provide further stability.

Abstract: A stairway climbing aid having a plurality of individual adjustable half-step members fixedly connected to a rigid elongated channel member at spaced locations along the length of the latter to comprise a rigid assembly. The channel member is connected to each of the half-step members adjacent the rear end of the latter and at an elevation and angle such that the channel member will extend upon or adjacent the outer edge of the tread of each step. The half-step members are longitudinally adjustable so that their length can equal the depth of the particular steps to which they are applied. Thus, any stairway can be readily modified to facilitate travel thereover by persons having difficulty in taking full steps, by applying such an assembly to the steps along one side of the stairway, after adjusting the individual half-steps to the depth of the treads.

Abstract: A lifting carriage having a rectangular frame provided with four corner posts for guiding an elevating platform mounted between these posts. Each post has a toothed rack on which a toothed gear mounted on the platform is engaged for raising the platform. The toothed gears ar actuated by a motor mounted on the platform through a power chain. The carriage is mounted on wheels which can be actuated by a motor for horizontally moving the carriage. The carriage is also provided with spinning wheels on its side, whereby, the carriage, when tilted on its side, can be moved sideways. The elevating platform is provided with guiding wheels adapted to abut against the corner posts for allowing a smooth sliding of the elevating platform.

Abstract: Ambulatory ladder apparatus constructed as a stepladder frame supported on a set of four base wheels. A user-powered drive is mounted under the lowermost step of the ladder, and is mechanically connected with a pair of the base wheels. A drive arm extending from the drive is accessible to a user while aboard the stepladder. By pumping action of the drive arm, the user-powered drive causes rotation of the base wheels, moving the ladder forward. A steering mechanism provided on the drive arm allows the user to direct the motion of the ladder during the pumping action. Thus, without requiring the user to dismount, the ladder may be easily repositioned by operation of the drive, allowing greater work efficiency in many repair, remodeling, painting and construction projects, by eliminating the additional time normally required for dismounting and repositioning the ladder.

Abstract: A support structure for suspending a window washer from the top of a building is disclosed. The support structure includes a counterweight carriage, a center support, a beam affixed to the counterweight carriage and the center support, and means for suspending the window washer from the outward end of the beam. The counterweight carriage has a frame member, a ballast container, and at least three wheels that allow the counterweight carriage to roll along the roof. The counterweight carriage further includes a steering mechanism to facilitate moving the carriage and support structure around on the roof.

Abstract: There is provided on the side of a mobile platform apparatus a surface engaging pivot in combination with side mounted wheels to grab an elevated surface and temporarily secure the apparatus during the process of loading the mobile platform onto the elevated surface. A high friction surface is provided on a pivot and wheels are mounted vertically above and protruding slightly beyond the pivot to accept the weight transfer only after the apparatus is substantially horizontal.

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: A retrofit kit for a portable scaffold having a relatively open frame supported for movement on a plurality of wheels and a platform for a worker disposed on the frame includes a wheel and a mount to mount the wheel to the open frame. The mount allows horizontal movement of the rotational axis of the wheel. The wheel may be steered by structure controllable from the platform to control the direction of the movement of the scaffold. A motor is provided and is operatively connected to the wheel for moving the scaffold in the direction selected by the steering means.

Abstract: A movable pedestal scaffold having two sets of wheels on the scaffold base to permit the scaffold to be rolled horizontally while the mast of the scaffold is in a vertical position. A transport frame is mounted for vertical movement on the mast, with such movement being powered by a hydraulic cylinder. A first set of wheels is mounted on the transport frame to support the scaffold at (1) a tilted position relatively near to vertical when the transport frame is close to the base member, and (2) at a tilted position substantially inclined from vertical when the transport frame is away from the base member. A second set of wheels is mounted on the transport frame closer to the mast and to the base frame then the first set of wheels on the transport frame, the first and second sets of wheels on the transport frame acting together to support the scaffold on an elevated horizontal surface as the scaffold is raise to or lowered from that surface.

Abstract: This invention is a combination stepladder and hand truck apparatus having a ladder support frame assembly pivotally connected to an upper portion of a hand truck support frame assembly and further including a support and lock plate assembly and a wheel support assembly which are both connected to a lower portion of the hand truck support frame assembly. The ladder support frame assembly includes a basic support frame with a support handle member at one end portion thereof and interconnected by axially spaced support step assembly. The support step assembly includes a lock or latch step member which is operable to support a user thereon and conjointly locks with the hand truck support frame assembly in a rigid condition when in the stepladder usage condition. The support and lock plate assembly includes a support plate member which is pivotally mounted on a support shaft member which, in turn, is secured across a lower portion of the hand truck support frame assembly.

Abstract: The ladder includes two separate ladder elements, which are pivotable and slidable relative to each other and can also be completely separated from each other. It can be used as a step-ladder and as a leaning type ladder. The ladder element is equipped with wheels, in order to simplify the transport of the collapsed ladder. In addition, an outwardly pivotable support plate is arranged between the wheels, so that the ladder element can serve as a hand truck, whereby the bent ends of the side beams serve as hand grips. The ladder has a simple construction and can be used in many ways in household use and in commercial operations.

Abstract: A portable tower or derrick which may be easily towed to a selected location and then erected by a single operator. While in the transporting position, the lower portion of the portable tower is supported by wheel assemblies mounted on at least two of the tower support legs. A pivoting tongue assembly is affixed to the tower at one end and may be coupled to a vehicle at the other end. The tongue assembly serves to support the upper portion of the tower during horizontal transport. A winch or other mechanical means is utilized to erect the tower by controlling the pivotal motion of the tower about the end of the tongue assembly. Once erected, horizontal sections of the tongue assembly may be utilized to ascend the tower.

Abstract: A power unit for attachment to scaffolding towers such as commonly used for overhead work in the installation of wiring, ductwork, painting, and finishing. A single power unit attached to one leg of a scaffolding tower can move, about the worksite, a large scaffolding tower assembly comprised of one or more individual scaffolding towers. Two power units working in tandem on separate legs of the scaffolding tower assemblage, provides increased maneuverability. Each power unit has separate motors to drive and to change the direction of a scaffolding tower assembly. One electric motor pivots the power unit about the scaffolding tower leg to which it is attached, thereby changing the direction of motion of the scaffolding tower assembly. Another electric motor of the power unit provides power to a drive wheel of the power unit, and consequently moves the scaffolding tower assembly.

Abstract: An electrically powered steerable scaffolding cart having a vertically positionable platform and handrails transports and supports a workman while he performs overhead work.

Abstract: Apparatus for use as a stairway, stepladder and the like has a pair of upper stringers and a pair of lower stringers, all connected at one end to a top structure; and a series of treads, each of which is pivoted to the upper and lower stringers. The axes of articulation associated with the upper stringers are offset vertically from those associated with the lower stringers so that the stringers may be swung about their points of connection with the top structure, without the treads deviating from the horizontal into a horizontal position of the stringers, in which the upper stringers rest on the lower stringers. Support elements are articulated to the top structure, and an automatic latching apparatus is provided to interconnect the support members with the stringers.

Abstract: A simple and versatile knock-down scaffold structure is provided, complete in itself, supported on four normally inert corner wheels, and capable, through adjustment and/or substitution of parts, to be varied in length, width and/or height, is modified by the optional addition of a power driving and steering unit comprising a fifth wheel and a reversible, variable speed driving motor therefor, through which the scaffold may be driven forward or backward, being desirably steered and controlled as to speed and direction by a workman on the scaffold. The power driving and steering unit may be varied in height to accommodate whatever variations of height are available in the conventional scaffold structure. It may also be varied in ground pressure to increase the driving traction as desired.

Abstract: A base frame with four wheels, two of which are powered by separate hydraulic motors connected in series so that the fluid flowing through one motor then flows through the other. A speed control is provided whereby the constant output of a hydraulic pump either passes entirely through the motors or is partially bypassed around the pump.