Abstract: A self-erecting suspension platform system having a work platform suspended between a sinistral modular mast and a dextral modular mast by a hoisting system. The modular masts are composed of at least two mast units stacked vertically and attached to one another. Each mast unit has a multifunction rail including a plurality of safety engagement devices and a stabilizer guide device, and a unit interconnection device. The work platform has at least two mast stabilizers that cooperate with the stabilizer guide devices to prevent undesired swaying of the suspended work platform. The work platform has a plurality of platform mast engagers cooperating with at least one of the mast safety engagement devices to releasably lock the platform to the modular masts. The hoisting system includes multiple carriages, hoists, and mast cables. Each carriage engages the associated mast so that the carriage may be conveniently slid up and down the mast.

Abstract: A stabbing basket, for a rig and for supporting a worker while stabbing joints of tubular members together during running operations, comprises a frame member for mounting the stabbing basket to the rig, a platform to support the worker, a carriage to slidably mount the platform to the frame member, vertical power means for moving the carriage vertically with respect to the frame member, an articulating boom, interconnecting the platform with the carriage, said articulating boom comprising a first segment and a second segment, and at least one pivoting actuator positioned between the first segment and the second segment.

Abstract: A platform lift apparatus enables the safe movement of objects to and from an attic storage space. The platform lift apparatus includes a frame, a drive mechanism, and a platform. The frame includes internal and external mounting surfaces. The drive mechanism is substantially disposed within the frame and is coupled to the internal mounting surfaces. The drive mechanism includes a plurality of rotatable, parallel shafts with each shaft further including at least one lift drum having an associated lift tether at least partially wound thereon and having an end hanging therefrom. The platform is coupled to each lift tether end and is thereby suspended from the frame. The platform is selectively movable by operation of the drive mechanism within in a vertical dimension between raised and lowered positions. The drive mechanism further comprises an electric motor operatively coupled to the plurality of parallel shafts.

Abstract: A platform lift for use with a vehicle includes a platform assembly having a plurality of support legs, and a lift mechanism having a support portion moveable between at least a first position and a second position. The platform assembly may be configured to be supported by the support portion when the support portion is in the first position, and further configured to be supported by the support legs substantially independent from the lift mechanism and the vehicle when the support portion is in the second position.

Abstract: Disclosed is a scaffold installed within a large structure such as a pressure vessel or a tank of a ship, and an insulation system construction method using the same. The scaffold for use in performing desired work within a large structure includes a supporting structure installed adjacent to both side surfaces and a top surface of the large structure, and a carrying unit installed movable along the supporting structure to allow materials to be carried or to provide a working space for a worker thereon, wherein the supporting structure is installed to be movable along a wall surface of the large structure.

Abstract: Disclosed is a scaffold installed within a large structure such as a pressure vessel or a tank of a ship, and an insulation system construction method using the same. The scaffold for use in performing desired work within a large structure includes a supporting structure installed adjacent to both side surfaces and a top surface of the large structure, and a carrying unit installed movable along the supporting structure to allow materials to be carried or to provide a working space for a worker thereon, wherein the supporting structure is installed to be movable along a wall surface of the large structure.

Abstract: A collapsible access tower has a chassis 10 supporting a pair of road wheels 11 and outriggers 16,17 to impart stability when in use, and a pair of extensible multi-section columns 26,50 carrying a platform 35. A section 27 of one column 26 is rigidly connected to the chassis and another section 33 of that column to the platform 35. The other column is configured as an extendible ladder 50 one section 51 of which is hinged to the chassis 10 and another section 52 of which is hinged to the platform 35. When the platform is in its lowermost setting, the hinged connections of the two sections 51,52 of the ladder 50 are co-axial so that the ladder may be pivoted to a transit setting. A winch arrangement 39 is associated with column 26 to allow raising and lowering of the platform 35.

Abstract: The invention is an elevator comprising a movable component, a vertical track mounted along an elevator shaft, a driven frictional engagement device for frictional engagement with one side of the track with a coefficient of friction, and a connected support disposed on an opposite side of the track. The frictional engagement device is pivotally mounted on a lever which pivotally supports an effective weight of the movable component whereby the lever makes an angle ?1 with the horizontal. The tangent of the angle ?1 is less than or equal to the coefficient of friction.

Abstract: Disclosed are various embodiments of a platform telescoping system which comprises a platform, a first supporting arm, a second supporting arm, a telescopic driving mechanism which comprises a first power output, end and a rotational driving mechanism which comprises a second power output end. The first power output end is integrated with the second supporting arm and causes the second supporting arm to move in a first direction, and the second power output end is integrated with the platform and causes the platform to pivot between a first position and a second position. The second supporting arm telescopes with respect to the first supporting arm for adjusting the position of the platform. The space occupied by the platform telescoping system may be reduced while its functions enhanced.

Abstract: A system for lifting a platform includes a frame attached to the platform. The invention has at least one upright member having equally spaced holes longitudinally aligned, with each of the holes having an upper surface and a lower surface. A motor is attached to the frame, and a pinion is driven by the motor. The frame carries the motor and pinion. The pinion has a plurality of equally spaced teeth that radially extend from the pinion. Each tooth has a roller that is freely rotatable about its axis. The rollers roll over the lower surface of the holes when the motor rotates the pinion in a direction to raise or lower the frame and platform. A safety dog is attached to the frame to prevent the platform from falling if a motor were to fail.

Abstract: The modular garage storage system includes a geared retraction system that allows a storage platform of the modular garage storage system to be lowered for easy access to loading and loading the storage platform, and that allows the storage platform to be raised up to be completely out of the way.

Abstract: Scaffold systems (SMV) to make substantially vertical building works, with sensitive time and manpower savings. In an advantageous embodiment, a scaffold is formed by a couple of modular semi-scaffolds which face each other, a semi-scaffold being placed in a cis-position over the work under erection and the other semi-scaffold is set in the trans-position.

Abstract: A device is provided which can be converted from a transporting cart to an erecting hoist for a hunter's tree ladder stand. The device includes components which can be assembled into the cart, disassembled, and re-assembled into the hoist which allows one person to transport the ladder stand, and to raise and lower the ladder stand to and from a position against a tree. The hoist includes a clamp with jaws which can be operated by the hunter on the ground so as to secure the hoist to the tree. A rope or cable extends through a pulley on the hoist so that the ladder stand can be raised into position by a hunter, single-handily. The hunter can then climb the ladder stand, which is secured to the hoist, which is secured to the tree, and further attach the platform of the ladder stand to the tree with one or more straps.

Abstract: A mast lift includes a base, a platform, and a lifting assembly connected between the base and the platform. The lifting assembly moves the platform between a lowered position and a raised position. A threaded driving rod is connected between the base and the lifting assembly, and a gas strut acts between the base and the lifting assembly and biases the lifting assembly and the platform toward the raised position.

Abstract: A power lift system is disclosed for use in association with scaffolding type systems. The system is designed to be erected in close proximity to a building wall or other support structure and is used to lift substantial loads to a desired elevation. The lift system has particular application for use in association with construction and/or the repair of a structure where a crane or elevator is not suitable or available.

Abstract: A platform scaffold system for building work, which typically is self-moving as a sole integrally body without needing disassembling and re-assembly its sub-systems, whereby the working times are shortened, pieces and components thereof do not go lost, and the maximal flexibility and safety will be reached. The platform is extensible in width and/or length and adjustable, in length, its support comprises two sub-systems (S3-S5) which are telescopically coupled to each other and to the platform (S1) by means of “overturned glasses” associated to the frame (T1) of the platform central element (1). One or several mechanisms act on the telescopically coupled support components also to make them pass from a work static state to a dynamic state on twirling wheels.

Abstract: A bracing system for providing seated stability to workers requiring a means of elevation in order to access the exteriors of buildings of several stories height. The present invention suspends a bosun's chair by means of a sturdy frame erected by means of two “legs” connected together to form an A-frame shape. Each leg is assembled using multiple pole sections fitted together by ferrules. A summit support rod, fitted to where the legs come together at the summit, leans against the building.

Abstract: A transportable, self-erecting, battery powered, vertical lift assembly includes a wheeled frame with a towing attachment mechanism. A linear guide member with an exterior roller chain member is pivotally secured to the frame. A carriage member with attached platform member is movably mounted to the linear guide member adjacent the frame. The carriage member includes an attached drive mechanism with a battery powered DC motor driving a gear unit operatively connected to a sprocket, which engages the roller chain member on the linear guide member. The carriage member and attached platform member are movable along the linear guide member by the drive mechanism to pivot and elevate the guide member, which engages a vertical support structure, and to elevate the carriage member and attached platform member. A safety brake assembly immobilizes the carriage member with respect to the linear guide member upon relative movement between the carriage member and drive mechanism.

Abstract: A flexible multi-conductor cable and a method of manufacturing a flexible multi-conductor cable, wherein the cable is adapted for use, particularly, in a mechanical cable track type lifting device. The cable includes two or more insulated conductors surrounded by a dual layer jacket. The dual layer jacket includes an inner layer having a TPE material with a higher tensile modulus, and an outer layer having a TPE material with a lower tensile modulus. The material of the cable is selected so that the cable is capable of surviving the external physical requirements of a mechanical cable track, as well as to prevent the transfer of the wiping effect onto the conductors.

Abstract: An elevating platform assembly (50) comprises a pair of laterally spaced, generally vertical masts (52). A drive mechanism (100) is coupled to each mast (52) and is moveable upwardly and downwardly along the masts. An elongated elevating platform (58) extends between the masts. A connection frame (150) couples each end of the elevating platform to a respective one of the drive mechanisms (100). Each connection frame (150) is pivotally coupled to the drive mechanism (100).

Abstract: An aerial work platform apparatus includes a platform adapted to be attached to one end of a boom or a lifting system and a frame coupled to the platform. The frame has a plurality of vertical and horizontal rails, and a plurality of adapters, each adapter being integrally attached to one of the vertical and horizontal rails and receives and secures a tube to the rail. Each adapter includes a sleeve for receiving the tube, at least one fastener for securing the tube to the sleeve, and a connecting unit for integrally connecting the sleeve to the frame.

Abstract: A stepladder comprises a front frame and a rear frame each formed of a pair of spaced side rails. A motor-driven step is slidably mounted on the front frame side rails. The motor is controlled with a remote unit allowing a worker to automatically raise and lower the step when accessing an elevated area.

Abstract: A bell crank and a mechanical link are included in an aerial lift system to mechanically constrain motion of a two-boom aerial lift mechanism to prevent the aerial lift system from accessing unstable positions. Typically an aerial lift is coupled to a vehicle via a turntable. The turntable includes a counterweight on a rearward side of the turntable to balance the booms and associated hardware as they are extended in a forward direction. If the booms are in certain rearward, or even vertical positions, the counterweight can cause the vehicle to tip and such unstable positions are to be avoided. By providing the bell crank proximate the pivot joint between upper and lower booms, with the bell crank coupling at pivot joints with: the lower boom, the mechanical link, and an upper hydraulic cylinder, the booms of the aerial lift system are mechanically constrained to avoid vehicle tipping.

Abstract: An elevated platform is provided. The elevated platform includes a platform, a central support structure, and an inflatable bladder structure. The inflatable bladder structure is coupled to and partially encases the central support structure. The inflatable bladder structure is also coupled to the platform so that the platform is moved in a first direction as the inflatable bladder structure is inflated and the platform is moved in a second direction opposite the first direction as the inflatable bladder structure is deflated.

Abstract: A device 1 for enabling access to a rotor blade 54 of a wind turbine, said device being adapted for being moved in the longitudinal direction of the rotor blade 54, the device comprising a frame structure 2, means for supporting and guiding the device in relation to the rotor blade, means for lowering and/or lifting the device in relation to the rotor blade, wherein said means for supporting and guiding the device in relation to the rotor blade are configured for contacting the rotor blade at regions at or near the front edge of the rotor blade and at or near the rear edge of the rotor blade, and wherein said means for supporting and guiding the device in relation to the rotor blade are configured for being adjusted to the rotor blade during movement of the device in order to maintain controllable contact at said regions, and wherein said means for supporting and guiding the device in relation to the rotor blade comprises a plurality of contact means 12, 14 at least one of which is adapted for being omnid

Abstract: An admission system, particularly for containers, with a raiseable platform. The system includes towers of carryable profiles with at least one longitudinal recess adapted for interference by at least one steering element. Each profile has an end portion adapted for interference with other carryable profiles. The profiles have the same cross-section and can be joined. Interlocking elements are placed between the profiles for joining. A toothed rack extends along the longitudinal direction of the profiles. A guiding element for connection with a working platform is connected to the at least one steering element and includes a pinion meshing with the toothed rack and a transmission for driving the pinion. Support elements are provided for attaching the profiles to a structure or other profiles. The invention also includes a method for assembly of such a system, a profile, a guiding element and support elements for such a system.

Abstract: The invention relates to a lifting assembly (10, 20, 30, 40, 50, 60, 70, 80, 90) comprising: a rack mast, a platform (12, 23, 33, 43, 53, 91), and at least one power unit (100, 300, 400, 500, 600, 800, 900, 901) which is mounted to the mast and which controls the vertical movement of the platform along the length thereof. The invention is characterized in that the power unit comprises a plurality of modular elements including at least one motor block (101, 200, 201, 301, 401, 501, 604, 621, 801, 904), at least one upper roller box (102, 205, 210, 305, 404, 503, 627, 903) and at least one lower roller box (103, 206, 304, 405, 502, 601, 629, 902). According to the invention, each of the modular elements is equipped with mechanical fastening means (610, 611, 612) which are aligned with the mechanical fastening means of an adjacent modular element.

Abstract: A Mechanical platform for champions disclosed. The mechanical device raises the winners rotationally enabling the audience to see the champions at a proportional speed such that the first one rises faster than the second one and the second one rises faster than the third one.

Abstract: A mobility device including multiple levels at different heights, beginning with a first level at substantially 4 to 6 inches from a floor surface, and with every subsequent level substantially 4 to 6 inches above the last level, and including a surface on the levels for a user to pull themselves onto, one level at a time, until the user is at a height by which they may either sit on a chair or regain their footing.

Abstract: The present invention is a powered lift platform including a platform, at least one guide rail section in operative contact with the platform, each of the at least one guide rail sections comprising at least one guide rail and in which a first end of each of the guide rail sections is configured to removably attach to a second end of a second guide rail section. The invention also includes a lift mechanism supported by the platform, a lift guide in operative contact with the lift mechanism and attached to the upper portion of the upper guide rail, a power supply to operate the lift mechanism. In a preferred embodiment, at least one wheel is operatively attached to the powered lift platform. Also presented is a method for securing the powered lift platform to a columnar-like support. Also presented is an extendable standoff.

Abstract: The self-elevating platform scaffolding includes a horizontal work platform suspended from a vertical mast tower and a unique lift mechanism mounted to the work platform, which raises and lowers the platform along the length of the tower. The lift mechanism uses a pinion wheel that directly engages a mast tower to raise and lower the work platform along the mast towers. The pinion wheel has a plurality of radially spaced cogs that seat within crescent shaped openings in the mast tower. The lift mechanism is mounted to the work platform adjacent the mast tower such that rotation of the pinion wheel causes the wheel to “walk” up and down the mast tower to raise and lower the platform. The geometric configuration of the pinion wheel is designed so that at least two of the cogs are always in contact with the mast tower. As the pinion wheel turns, each successive cog seats within an adjacent crescent slot in the mast tower with its contact edge bearing against the bottom edge of tower opening.

Abstract: The present invention discloses a multi-purpose load lifting work platform or/and composite bridge structure, comprising a framework, at least one work platform, a drive mechanism, and an electrical control devices. One end of the pole-shaped structure is connected with the framework in a movable manner, and the other end of the pole-shaped structure is connected with the work platform in a movable manner, the work platform can run with the pole-shaped structure together. The work platform can run in a curve track relative to the framework by power, and can stop at any position in running track. This invention can provide two platforms working coordinately or a single platform working independently. The working area of the two platforms greatly exceeds that of the existing common equipment with a single platform. It can load bulky objects without sway, and can also be used as composite or assembly bridge structure.

Abstract: Expandable load bearing device for use on a ladder and comprising an outer member (20), an inner member (21) movable within the outer member, and ratchet means having a pawl (26) attachable to the outer member and a rack (22) attachable to the inner member, the pawl being movable into and out of engagement with the rack to prevent the movement of the inner member towards the outer member, and the pawl having a shoulder (36d) arranged to bear upon a load transfer member (24) on the outer member when the pawl is in engagement with the rack.

Abstract: An apparatus comprising a frame scaffold with a mechanically operated sliding support, as well as methods of assembling, using and disassembling a frame scaffold using the sliding support are disclosed. The apparatus provides for at least one individual to vertically ascend and/or descend along the perimeter of frame scaffold by mechanical operation. The operator of the apparatus is in close proximity to the scaffold. The apparatus does not require the support of an additional structure (i.e., it is self-supporting). The apparatus provides improved safety and efficiency in the assembly and disassembly of frame scaffold.

Abstract: A universal platform device includes a support member and at least one base member having a first surface configured to be positioned on a primary surface. The base member can be pivotably coupled to the support member, and includes a plurality of gaseous cells at least toward the first surface and flexible regions at least between the respective gaseous cells. The weight of the object or person being supported on platform device deforms the flexible material and the gaseous cells. Upon deformation of the flexible regions and gaseous cells, the shape of the mating portion substantially conforms to the shape of the primary surface. The gaseous cells at the mating portion expand to form numerous suction cups and the base member clasps on to the primary surface.

Abstract: A lift system is coupled between a work platform and a mast on a mast lift. The lift system includes an overload clutch that slips upon an overload on the lift system, an overrun brake that prevents the lift system from running beyond a fully lowered position and that prevents the lift system from running if the platform is hung up, and an emergency brake. The lift system is safe and lightweight and is effective for controlling a position of the work platform on the mast.

Abstract: A platform lift for use with a vehicle includes a platform assembly having a plurality of support legs, and a lift mechanism having a support portion moveable between at least a first position and a second position. The platform assembly may be configured to be supported by the support portion when the support portion is in the first position, and further configured to be supported by the support legs substantially independent from the lift mechanism and the vehicle when the support portion is in the second position.

Abstract: Apparatus for elevating, laterally and rotationally positioning an aerial work platform relative to a support structure such as a mobile vehicle. In one embodiment a platform supporting carriage is mounted for sliding movement along a support beam affixed to a boom and the platform is mounted on the carriage permitting rotation of the platform about a substantially vertical axis. In a second embodiment a four bar linkage is used for longitudinally moving a rotatable platform. One or more powered means may be provided for elevating, leveling and longitudinally and rotationally positioning the work platform.

Abstract: A mobile mount for attachment of a fall arrest system is provided for example for aircraft and includes a base carried on ground wheels and a support which is adjustable in height upstanding from the base and an arm cantilevered over the base. At least one receptacle is mounted on the arm of the support at a position located over the base for attachment to a personal fall arrest system including a harness for one or more persons, with the receptacle, base and support being designed and arranged to receive a loading from the personal fall arrest system sufficient to accommodate a fall of the person from the elevated structure.

Abstract: The invention relates to a lift cage, in particular a lift cage for persons, for navigating towers, cranes, wind energy plants, pillars of wind energy plants or the like, with a floor 4, with a plurality of side walls 11 rigidly connected thereto and with a lateral opening 12 which can be closed by means of a door 20 between two opposing side walls 11, the door 20 having two door wings 21 which are displaceable parallel to each other. In order to allow secure locking of the door and convenient entry, according to the invention one door wing 21 is displaceably supported by the other door wing by means of a plurality of longitudinal pullouts and guided by means of first guide means in guides 15 parallel to the lateral opening 12 and by means of second guide means in guides 16 parallel to one of the side walls 11.

Abstract: A scaffold assembling of a large component for a boiler requiring inspection is not performed by a high-place work but assembled safely and in a short time. The scaffold is assembled to the large component for the boiler supported by a component supporting beam at the ground side before it is attached to a steel frame main-beam 16. Scaffold lifting/supporting beams interposing coil spaces of a superheater 14 are suspended on wires 36 lifted down from spaces of a ceiling tube wall 34 being a horizontal member of the superheater 14. The scaffold lifting/supporting beams 32 are lifted to raise little by lithe within the superheater, and scaffold components are assembled sequentially toward downward. After a required number of steps of scaffolds are assembled, the scaffold lifting/supporting beams 32 are coupled to the ceiling tube wall 34 to be supported. Finally, the superheater 14 is raised by a lifting means to install to the main-beam.

Abstract: A load displacement apparatus to displace a mobile platform along a structure includes a worm screw mounted on the platform for rotation about its axis that meshes with a plurality of support blocs mounted on the structure. The support blocs are spaced apart from one another along the structure to be successively engaged by the worm screw. Each support bloc includes a plurality of bearing balls freely movably supported and retained therein to selectively and movably engage the worm screw over at least an arc segment thereof such that the worm screw is always in meshing engagement with at least one of the support blocs. The invention also refers to a scaffolding system incorporating the apparatus.

Abstract: An adjustable, articulable platform, changeable to and from a “U” shape to an “H” shape, is attachable to the distal end of an articulable support arm of a transport vehicle. The platform is arranged to adjustably surround an elevated chimney on at least three sides thereof. The platform comprises: a lower anchor plate centrally disposed within an elongated lower support frame; a rear anchor plate connected perpendicularly to the lower anchor plate, the rear anchor plate centrally and connectively disposed within an elongated rear wall frame, comprising bridging portions of the platform. A right sidewall frame and a left sidewall frame is connected to respective end portions of the elongated rear wall frame.

Abstract: The claimed work platform system, alternatively dubbed by the inventor as “Miniscaffold”, provides a compact, versatile, and portable method of supporting workers engaged in various elevated construction or maintenance activities. The claimed work platform rides upon a number of locking floor casters. Each floor caster is mounted to a removable, telescoping support which may be readily relocated inward to accommodate access through narrow aisles or outward to enhance the platform's stability. Each telescoping support is also fitted with an individual jack mechanism to compensate for the inevitable variations in ground or floor elevation typical at construction or work sites. The “Miniscaffold” is also constructed from interlocking square tube members which enhance the work platform's stability and thus eliminate the obtrusive and cumbersome diagonal supports found on most scaffolding.

Abstract: A safety system and method for objects moved by a driving cabling system. Offers a redundant back-up system that activates when the main cable system fails.

Abstract: An aerial work platform apparatus includes a platform adapted to be attached to one end of a boom or a lifting system and a frame coupled to the platform. The frame has a plurality of vertical and horizontal rails, and a plurality of adapters, each adapter being integrally attached to one of the vertical and horizontal rails and receives and secures a tube to the rail. Each adapter includes a sleeve for receiving the tube, at least one fastener for securing the tube to the sleeve, and a connecting unit for integrally connecting the sleeve to the frame.

Abstract: A hand truck having a folding platform attached to a wheeled base. The base having an arrangement of stabilizing bars and feet and vertically extensible masts that raise and lower the folding platform by operation of a motor attached to the base. The platform of the hand truck, when in the extended position, has modular removable railings attached along the perimeter of different platform sections. The platform is collapsible about pivot pins and suspended by chains attached to brackets atop the extensible masts.

Abstract: A collapsible stepstool for storing underneath a cabinet and extending from there under when in use includes a platform member for supporting a user. A top frame member supports such platform member. A bottom frame member supports at least one of such platform member, such top frame member, and a combination thereof. A mechanism for facilitating vertical movement of such platform member is attached to at least one of such top frame member, such bottom frame member, such platform member, and a combination thereof for selectively raising and lowering at least one of such platform member, such top frame member, and a combination thereof. At least one mechanism is disposed on such bottom frame member for facilitating horizontal movement of such collapsible stepstool such that such collapsible stepstool may be extended from underneath such cabinet for use and may be returned to a position underneath such cabinet for storage.

Abstract: A system for lifting a platform includes a frame attached to the platform. The invention has at least one upright member having equally spaced holes longitudinally aligned, with each of the holes having an upper surface and a lower surface. A motor is attached to the frame, and a pinion is driven by the motor. The frame carries the motor and pinion. The pinion has a plurality of equally spaced teeth that radially extend from the pinion. Each tooth has a roller that is freely rotatable about its axis. The rollers roll over the lower surface of the holes when the motor rotates the pinion in a direction to raise or lower the frame and platform. A safety dog is attached to the frame to prevent the platform from falling if a motor were to fail.

Abstract: An adjustable, articulable platform, changeable to and from a “U” shape to an “H” shape, is attachable to the distal end of an articulable support arm of a transport vehicle. The platform is arranged to adjustably surround an elevated chimney on at least three sides thereof. The platform comprises: a lower anchor plate centrally disposed within an elongated lower support frame; a rear anchor plate connected perpendicularly to the lower anchor plate, the rear anchor plate centrally and connectively disposed within an elongated rear wall frame, comprising bridging portions of the platform. A right sidewall frame and a left sidewall frame is connected to respective end portions of the elongated rear wall frame.