Patent Description:
The present invention relates generally to concrete structures and floors of buildings and the processes of installing and removing beams and panels or formwork used to form concrete structures and floors of buildings.

Formwork includes temporary or permanent molds or supports into or onto which concrete or similar materials are poured in order to create walls and slabs of buildings. In known building practice, formwork is assembled on a surface or on a lower floor level to form the next level of the building above. Once the concrete slab has sufficiently hardened, the formwork may be removed. Traditional plywood formwork is built on site, with the plywood panels being supported on beams and shoring posts. It is easy to produce but time-consuming and dangerous to build and to remove, particularly for larger structures.

The document <CIT> discloses a machine according to the preamble of claim <NUM>.

The present invention provides a machine according to claim <NUM> for safe and efficient removal of the panels and beams of formwork systems. The machine includes a motorized, wheeled base having a raisable platform that can extend upward toward the formwork to be removed. The machine is adapted to remove plywood or formwork from the underside of a placed and cured slab or ceiling structure.

In accordance with an aspect of the invention, the machine operates to remove plywood formwork from the underside of a concrete slab. The machine includes a formwork-removal apparatus, which is attached to the raisable platform, and which includes an arm, a wedge element, and a formwork-retaining mechanism. The wedge element includes one or more wedges attached to the arm. As the machine is maneuvered, the wedge mechanism engages the formwork, applying a separating force to partially separate or free the formwork from the slab. As the formwork is partially separated or freed, the formwork-retaining mechanism secures the partially separated formwork at the arm for removing the formwork and moving the removed formwork to a targeted location where it can be stacked and/or stored for reuse.

In accordance with another aspect of the present invention, the machine provides a beam-removal apparatus. The beam-removal apparatus includes an arm and a beam-gripping mechanism. The beam-gripping mechanism may comprise a gripper that conforms to and clamps at the central section of an I-beam. Optionally, the beam-removal apparatus may include a rotary actuator so that the gripper may grip the beam and the rotary actuator may twist the beam to free the beam for removal. The machine may reposition the removed beam and may stack the removed beams at a targeted location.

These and other objects, advantages, purposes and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings.

To create poured-concrete slabs of buildings, workers assemble formwork panels to define spaces that are then filled with concrete. The formwork panels, which typically comprise individual sheets of plywood supported on beams, support the poured concrete until the slab or wall has sufficiently hardened, at which time workers remove the formwork as refuse or for reuse. For example, workers may remove the formwork from one level of a multi-level building after the concrete hardens and use the formwork to form the next higher level of the building. Traditionally, workers assemble formwork for upper-level slabs using plywood panels supported from below by a system of beams bearing the weight of the poured concrete as it hardens. The beams, in turn, are supported by shoring posts resting on a firm base, such as a lower-level slab. When the upper-level slab hardens sufficiently, workers manually disassemble and remove the beams that support the plywood panels, then pull or pry the formwork panels free from the bottom or underside of the slab. This process is tedious and time consuming and exposes workers to hazards, such as from falling material. The formwork-removal and/or beam-removal machines of the present disclosure streamline this process, reducing costs while increasing worker safety.

Referring to <FIG>, a formwork removing machine or device <NUM> for removing panels and beams of formwork systems includes a wheeled, motorized base <NUM>, a lift mechanism <NUM> disposed at the wheeled base <NUM>, and a formwork-removal apparatus or device <NUM> attached at the lift mechanism <NUM> for removing formwork. For purposes of this disclosure, the term "formwork" may refer to plywood sheets, support beams, or other materials applicable within the context of the usage.

The wheeled base <NUM> has four wheels, which may be independently powered wheels, and which may be independently steered, permitting a high degree of maneuverability on the job site. The four wheels may each be steered by, for example, pivoting around a vertical axis and having independent steering mechanisms. Optionally, the front wheels and/or the rear wheels may be steered in tandem by, for example, both of either the front and/or rear wheels being connected to an axle. Optionally, other wheel configurations may be used such as, for example, a three-wheeled base or a base having more than four wheels, or a base propelled by tracks driven by rotationally driven wheels.

In the illustrated embodiment, the lift mechanism <NUM> comprises a scissor lift having a plurality of pivotally connected sections that pivot relative to one another to raise and lower the formwork removal device via the extension and retraction of a hydraulic cylinder 112a disposed at the base <NUM>. The scissor lift, when extended or raised, lifts or moves the formwork-removal device <NUM> from a position near or resting on the base <NUM> (<FIG>) to a position at or near the formwork (<FIG>) for removal of the formwork from the underside of the concrete slab, as discussed below. The scissor lift, when retracted (as shown in <FIG>), folds into a compact configuration on or above the wheeled base <NUM>, with the formwork-removal device <NUM> lowered down to the lowered or retracted state. As shown in <FIG>, the lift structure <NUM>, when lowered or retracted, may stow at least partially in a cavity at the wheeled base <NUM> such that the machine <NUM> may be more compact for storage or maneuverability. The lift structure <NUM> may also hold a variety of different height positions, as illustrated in <FIG> and <FIG>, so as to reach formwork at differing elevations from the wheeled base <NUM>.

As shown in <FIG>, the formwork-removal device <NUM> is mounted to the lift mechanism <NUM> at an extendable and retractable boom <NUM> that is extendable via actuation of an actuator 115a, such as, for example, a hydraulic cylinder or the like. The formwork-removal device <NUM> may also be mounted to the lift mechanism <NUM> directly or to a platform, structure, or otherwise coupled to the lift mechanism <NUM> opposite the base <NUM> such that when the lift mechanism is extended or raised from a retracted or lowered state to an extended or raised state, the formwork-removal device <NUM> is extended or raised away from the base <NUM>.

Referring to <FIG>, the formwork-removal device <NUM> is configured to remove a piece of formwork, a beam, or a piece of plywood <NUM> from the underside of a hardened slab of concrete and to hold the removed piece of plywood <NUM>. The formwork-removal device <NUM> comprises a support portion or structure <NUM> that is attached at the end of the boom <NUM>, with a grasping device <NUM> pivotally mounted at the support portion <NUM> and/or at the end of the boom <NUM>. The grasping device <NUM> is pivoted upward and downward via an actuator 119a, such as, for example, a hydraulic cylinder or the like. The grasping device <NUM> includes a support structure or base <NUM> that is pivotally mounted at the support structure <NUM>, and includes a wedge element <NUM> or mechanism that extends from the support structure <NUM> for separating the formwork from the slab (in a manner to be described further below) and a grasping element <NUM> or mechanism or arm that cooperates with the wedge element <NUM> to grasp and hold the removed plywood <NUM>.

The grasping element <NUM> is pivotally mounted at the support structure <NUM> and is pivoted relative to the wedge element <NUM> between an opened state (<FIG>) and a closed state (<FIG>) via an actuator 122a, such as a hydraulic cylinder or the like. The grasping element <NUM> may be pivoted from an open state to a closed state such that the grasping element <NUM> engages the piece of plywood <NUM> between the grasping element <NUM> and the support structure <NUM> or wedge element <NUM>, securing the plywood <NUM> in position. As best shown in <FIG> and <FIG>, the opposing surfaces or edges of the grasping element <NUM> and the wedge mechanism <NUM> may be toothed or serrated or knurled or roughened or otherwise configured to enhance gripping of the plywood formwork <NUM> that is clamped between the grasping element <NUM> and the wedge mechanism <NUM>.

As shown in <FIG>, the formwork-removal device <NUM> also includes a support arm <NUM> that extends from the grasping device <NUM> and pivots with the support structure <NUM> of the grasping device <NUM> when the grasping device <NUM> is pivoted upward and downward via the actuator 119a. The support arm <NUM> may be removably coupled to the support structure <NUM> and is configured to support the removed plywood <NUM> at a point distanced from where the plywood <NUM> is held between the grasping element <NUM> and the wedge element <NUM> or support structure <NUM>. At a distal end from where the support arm <NUM> is coupled to the support structure <NUM>, the support arm <NUM> may comprise a rounded cross support element <NUM> such that a removed piece of plywood <NUM> rests upon the rounded cross support <NUM> of the support arm <NUM>. The rounded cross support <NUM> may comprise a folded disk or plate or bar substantially forming a cap over a distal end of the support arm <NUM> and extending horizontally from the support arm <NUM> so as to substantially form a T-shape. The rounded cross support <NUM> provides support to a piece of removed plywood <NUM> to prevent twisting or bending or breaking of the removed plywood <NUM> during removal of the plywood <NUM> or movement or raising or lowering of the formwork-removal device <NUM>. The rounded cross support <NUM> also provides a rounded contact surface so as to reduce the chance of the formwork <NUM> catching or snagging or tearing or ripping upon an edge of the support arm <NUM>.

Thus, the formwork-removal device <NUM> is operable to remove a piece of formwork <NUM> from the underside of a slab of hardened concrete. For example, the formwork removing machine <NUM> may be positioned substantially underneath a piece of plywood formwork <NUM> connected to a hardened concrete slab (after the concrete slab has been placed on the plywood and has sufficiently cured and hardened). The lift structure <NUM> may raise the formwork-removal device <NUM> to a targeted height to engage the plywood <NUM>, whereby the actuator 119a moves the grasping device <NUM> and pivots the grasping device <NUM> upward to engage the wedge element <NUM> with the piece of plywood formwork <NUM>, with the support arm <NUM> positioned at the formwork <NUM> with its distal support end spaced from the wedge element <NUM>.

When positioned with the wedge element <NUM> at the formwork, the grasping device <NUM> may be extended to move the wedge element <NUM> to dislodge the formwork. For example, the boom actuator 115a may extend the boom <NUM> to apply a force upon the plywood <NUM> at the wedge element <NUM>, whereby the grasping element <NUM> is pivoted to grasp or clamp the formwork <NUM> between the grasping element <NUM> and the underside of the wedge element <NUM> or support structure <NUM>, with the support arm <NUM> supporting a distal portion of the formwork <NUM>. The device <NUM> (while holding the removed formwork) may be lowered via the lowering of the lift structure <NUM> and the grasping device <NUM> may be pivoted downward (such as in <FIG> and <FIG>) relative to the support structure <NUM> at the end of the boom <NUM> and the grasping element <NUM> may be pivoted to its opened position to release and drop the removed formwork <NUM>.

Referring to <FIG>, an additional embodiment of the formwork removing machine <NUM> for removing formwork panels and beams is provided. The formwork removing machine <NUM> may include similar aspects and functions of the formwork removing machines discussed throughout this disclosure such that a complete description of aspects of the machines need not be repeated herein. It should be understood that the multiple possible embodiments of the formwork removing machine may include or exclude elements contained within one or any combination of the illustrated embodiments provided by this disclosure. The formwork removing machine <NUM> includes a wheeled, motorized base <NUM>. The base <NUM> has four independently powered wheels, each of which may be steered by pivoting around independent vertical axes. Optionally, the front wheels and/or the rear wheels may be steered in tandem by, for example, connecting the front wheels and/or the rear wheels via axles. Optionally, other wheel configurations may be used, such as, for example, a three-wheeled base or a base having more than four wheels, or a base propelled by tracks driven by rotationally driven wheels. The formwork removing machine <NUM> includes a raisable structure <NUM> disposed at the wheeled base <NUM>, with a formwork-removal apparatus or device <NUM> attached at the raisable structure <NUM> for removing formwork and/or beams.

In the illustrated embodiment, the raisable structure <NUM>, similar to lift structure <NUM>, comprises a scissor lift having a plurality of pivotally connected sections that pivot relative to one another to raise and lower the structure via extension and retraction of a hydraulic cylinder 212a at the base <NUM>. The scissor lift, when extended or raised, such as shown in <FIG> and <FIG>, lifts or moves the formwork-removal device <NUM> to position it at the formwork or plywood <NUM> for removal of the formwork from the underside of the slab. The scissor lift, when retracted, such as shown in <FIG>, folds into a compact configuration on the wheeled base <NUM>, with the formwork-removal device <NUM> lowered down to the lowered or retracted state.

As shown in <FIG>, the formwork-removal device <NUM> is configured to hold a piece of plywood formwork <NUM> that the machine <NUM> may have removed from the bottom of a hardened slab of concrete at a height near a raised/extended position of the raisable structure <NUM>. The formwork-removal device <NUM> includes an arm <NUM>, a wedge mechanism <NUM> for separating the plywood <NUM> from the slab, and a retaining mechanism <NUM> to hold the removed plywood <NUM>. The wedge mechanism <NUM> is located at the leading end of the arm <NUM>, distal from where the arm <NUM> attaches at the raisable structure <NUM> so that as the machine <NUM>, with the raisable structure extended or raised to position the wedge mechanism <NUM> at the plywood <NUM> and concrete, moves forward, the wedge mechanism <NUM> engages with the plywood <NUM> and is urged between the plywood and the concrete slab, applying a force to separate the plywood <NUM> from the concrete slab. Optionally, the arm <NUM> may be extendable from the raisable structure <NUM> via a hydraulic actuator 218a or extendable boom or similarly capable mechanism, as shown in <FIG>. The hydraulic actuator 218a may enable the wedge mechanism <NUM> to extend greater distances from the raisable structure <NUM>. The hydraulic actuator 218a may also enable the wedge mechanism <NUM> (when raised so that the wedge element <NUM> is at the plywood <NUM> and underside of the slab) to engage the plywood <NUM> and move between the plywood and concrete slab as the hydraulic actuator 218a extends forward, while the wheeled base <NUM> remains stationary such that the extending motion of the hydraulic actuator 218a, rather than the motion of the wheeled base <NUM>, primarily creates the separating force applied upon the plywood <NUM> attached at the underside of the concrete slab.

When the wedge mechanism <NUM> has been moved and positioned a sufficient amount into the interface between the plywood <NUM> and concrete slab, the retaining mechanism <NUM> operates to clamp or grasp the plywood <NUM> for removing the plywood <NUM> from the concrete slab and moving the plywood <NUM> to a targeted location. The retaining mechanism <NUM> may include a hydraulically activated jaw that supports and holds the plywood <NUM> after removal from the slab. For example, and such as best seen in <FIG>, the retaining mechanism <NUM> includes a hydraulic actuator 222a (or other suitable actuating device) that is extended to pivot a plywood engaging element into engagement with the plywood <NUM> to clamp the plywood <NUM> between the plywood engaging element and the arm <NUM>. When the plywood is clamped in this manner, the formwork-removal device <NUM> may be lowered via lowering of the raisable structure <NUM> to pull the plywood downward and to further and fully remove the plywood <NUM> from the concrete slab.

Thus, the plywood <NUM> may be carefully lowered from the height of the slab to a suitable or targeted storage location. For example, and such as shown in <FIG> and <FIG>, the machine <NUM> may lower the plywood <NUM> to a point near the ground surface by retracting the raisable platform <NUM> to a lowered position while the formwork-removal device <NUM> continues to securely hold the plywood <NUM>. As shown in <FIG>, the machine <NUM> may open the retaining mechanism <NUM> by retracting the hydraulic actuator 222a to release the removed plywood <NUM> to rest on the ground surface.

Optionally, and such as shown in <FIG>, the formwork removing machine <NUM> may include a dual-wedge wedge mechanism <NUM> and a receiving and retaining mechanism <NUM>. As shown, the wedge mechanism <NUM> includes a pair of wedges or wedge-shaped elements, each wedge located at one side of the leading or distal end of the arm <NUM>, which may comprise a pair of spaced apart arms, one at each wedge, such that each wedge engages with the plywood <NUM> and underside of the slab or ceiling in parallel. Thus, the separating force may be more evenly distributed across the plywood <NUM>, reducing possible damage to the plywood <NUM>. Additional wedges may be used to further distribute the removal forces.

The receiving and retaining mechanism <NUM> includes a shelf or receiving structure located below the wedge mechanism <NUM> to receive removed or partially removed plywood <NUM>, and a hydraulically activated clamping mechanism 222b to secure the removed plywood <NUM> at the receiving structure of the arm <NUM> and retaining mechanism <NUM>, such as by clamping the plywood <NUM> against a portion of the arm <NUM> located above the shelf or against the lower part of the receiving structure <NUM>. Each wedge of the wedge mechanism <NUM> is attached to the leading end of the arm <NUM> on a structure that allows the wedge to pivot on the structure to conform to the surface of the slab during removal of the plywood. Optionally, the center of gravity of the wedge may cause the wedge to pivot upwards and maintain contact with the bottom of the slab so that, as the wedge system <NUM> moves forward, the point of the wedge is forced between the slab and the formwork <NUM>. Optionally, and as shown in <FIG>, the wedge elements <NUM> may be biased via a torsional spring or other biasing means to pivot the wedges so that the tips of the wedge elements <NUM> point partially upward towards the ceiling or hardened concrete slab and formwork. The wedge elements <NUM> thus may be biased toward a position or orientation where they are readily forced between the plywood <NUM> and the underside of the concrete slab when the arm is moved toward the plywood <NUM>.

As shown in <FIG>, during operation of the formwork removing machine, the wedge mechanism <NUM> is moved into engagement with the plywood <NUM> and the retaining concrete slab (illustrated as "Ceiling") such that the wedges may displace the plywood <NUM> from the concrete slab as the formwork removing machine moves the wedge mechanism <NUM> further into the area between the plywood <NUM> and the concrete slab, the wedges working to pry or separate part of the plywood <NUM> from the concrete slab. As shown in <FIG>, once the wedge mechanism <NUM> is positioned sufficiently far in and between the plywood <NUM> and the concrete slab, such that part of the plywood <NUM> is received in the receiving and retaining mechanism <NUM>, the clamping mechanism 222b may be activated to engage the plywood <NUM>. The clamping mechanism 222b may be activated, for example, by extending or retracting a hydraulic actuator connected to a clamp head, thereby pivoting the clamp head to engage and clamp the plywood <NUM> between the clamping mechanism 222b and a portion of the arm <NUM> or between the clamping mechanism 222b and the retaining mechanism <NUM>. With the plywood <NUM> secured and clamped in the receiving and retaining mechanism <NUM>, the formwork-removal device <NUM> may be lowered and moved, such as via lowering the extendable structure <NUM> and maneuvering the wheeled support, to remove the plywood <NUM> from the concrete slab. After removal of the plywood <NUM>, the formwork removing <NUM> machine moves the plywood <NUM> to a targeted location, whereby the hydraulic actuator is retracted to release the plywood <NUM>, allowing the removed plywood <NUM> to be placed at the targeted location.

As shown in <FIG>, the receiving and retaining mechanism <NUM> is configured to receive a portion of the plywood <NUM> therein as the wedges <NUM> separate part of the plywood <NUM> from the concrete. The length of the receiving portion may be selected to receive an end part of the plywood <NUM> therein, or may be dimensioned to receive a larger portion of the plywood <NUM>. For example, and such as shown in <FIG>, the receiving portion may be dimensioned to receive a substantial part, such as half of an <NUM> foot length of plywood, therein. Optionally, with a larger receiving portion, the clamping mechanism 222b may comprise two clamping elements or may have an inboard clamping element that is spring-loaded or otherwise biased to apply a retaining force at the plywood <NUM> when the plywood <NUM> has been sufficiently received in the receiving portion with the outer clamping element having an actuator for clamping the plywood at the outer end of the receiving structure. Optionally, the arm <NUM> and wedge mechanism <NUM> may be extendable relative to the lower part of the receiving portion, as shown in <FIG>, via a hydraulic actuator 218a or linear actuator or the like that, when operated, moves or extends/retracts the wedge mechanism <NUM> relative to the receiving and clamping portion <NUM>.

Thus, the formwork removing machine operates to separate the plywood <NUM> from the underside of a concrete slab or ceiling in an automated and safe and efficient manner, without requiring an operator to manually remove the plywood <NUM>. The machine <NUM> engages the plywood <NUM> and pulls the plywood <NUM> down from the underside of the concrete slab and can readily move the removed plywood <NUM> to a targeted location, such as the ground surface or a shelf or cart or the like. The removing device <NUM> includes one or more wedges <NUM> that function to separate part of the plywood <NUM> from the concrete slab, whereby a clamping or retaining device <NUM> is actuated to clamp the plywood <NUM> for forcibly removing the plywood <NUM> from the concrete slab.

Optionally, the arm <NUM>, including the wedge <NUM> at the distal end of the arm from the raisable structure <NUM>, may be pivotally mounted at the raisable structure <NUM> and may pivot upward from the raisable structure <NUM>, such as shown in <FIG>. In such an application, an upward force, which may be applied by a spring 220a or other biasing element, causes the arm <NUM> and wedge <NUM> to be biased upward toward and into engagement with the concrete slab so that the wedge is forced between the plywood <NUM> and the concrete slab when the arm <NUM> is moved toward the plywood <NUM>. Optionally, the raisable structure <NUM> may comprise any suitable mechanism for raising/extending or lowering/retracting the arm <NUM> and plywood removing device <NUM>. For example, the raisable structure <NUM> may comprise a telescoping arm or an articulating arm or the like that extends or retracts or adjusts responsive to one or more hydraulic actuators or the like (such as an arm and controls utilizing aspects of the arms and booms and controls described in <CIT>, which is hereby incorporated herein by reference in its entirety). Optionally, the arm <NUM> may be raised and lowered by a manually operated and drivable hydraulic lift or a jack lift. For example, the wheeled base <NUM> may be a ride-on wheeled base or machine, such as forklift type machine or order picking machine, optionally with a platform or other receptacle or bin or the like beneath the formwork removing device for the plywood <NUM> to fall onto as it is removed.

The wheeled machine <NUM> may be dimensioned to maneuver easily between shoring posts while removing beams and formwork. The wheeled machine <NUM> may also be compactly stowed when not in operation. During operation, the wheeled machine <NUM> is remotely controllable, such as via an operator controlling the machine via a hand-held remote controller that is in wireless communication with the wheeled machine <NUM>, further increasing worker safety. Optionally, the wheeled machine <NUM> may tow a trailer onto which the removed formwork may be stacked and stored, e.g., to permit efficient transportation from the work site.

Optionally, and such as shown in <FIG>, a formwork removal machine <NUM> may include a plywood gripping device <NUM> that comprises a pneumatically operated gripper 324a attached to an articulating and/or extending arm <NUM>. The arm may extend from a scissor lift, such as a lift similar to the raisable structure <NUM> or lift structure <NUM>, discussed above, that is raisable to position the gripper <NUM> at the underside of the plywood <NUM> to firmly engage the gripping elements 324a of the gripper at the plywood <NUM> from below. The wheeled base and lift or raising mechanism of the machine <NUM> may be substantially similar to the bases and mechanisms of the machines <NUM>, <NUM>, discussed above, such that a detailed discussion of these aspects of the machines need not be repeated herein.

When the gripper <NUM> is engaged with the underside of the plywood <NUM>, the gripper <NUM> may be activated to generate a suction at the plywood <NUM> to secure the plywood <NUM> at the gripper element 324a. The gripper <NUM> is then lowered, for example, by retracting the arm <NUM> or by lowering the raisable structure, freeing the formwork or plywood <NUM> from the underside of the concrete slab or ceiling. As shown in <FIG> and <FIG>, after removing the formwork <NUM>, the gripper <NUM> continues to retain the plywood <NUM> as the arm <NUM> lowers or otherwise repositions the plywood <NUM>, such as to move and orient the plywood <NUM> at a targeted location, whereby the gripper element 324a is deactivated to release the plywood <NUM> to store or stack the plywood <NUM> at a targeted location. As shown in <FIG>, the gripper <NUM> is pivoted relative to the end of the arm <NUM> via an actuator 326a, such that the gripper can be initially positioned facing upward toward the formwork (<FIG> and <FIG>), and then, after removing the formwork, can be pivoted to face generally downward (<FIG> and <FIG>) for releasing the formwork at the targeted location.

When removing the formwork or plywood from beneath a cured concrete slab or ceiling structure, at least some of the support beams and posts supporting the plywood or holding the plywood in place must be removed before the plywood is removed. Optionally, and now with reference to <FIG>, a formwork removal machine or beam-removal machine <NUM> includes an arm <NUM>, which is mounted at a wheeled base <NUM>, similar to a wheeled base <NUM> or <NUM> or <NUM> described above, and a gripping mechanism <NUM> located at a distal or beam end of the arm <NUM>. The gripping mechanism <NUM> includes a pair of pivoting jaws having a gripping surface that conforms to the central section of an I-beam <NUM>.

As shown in <FIG>, the arm <NUM> may be mounted at a raisable structure <NUM>, such as a scissor lift structure or the like, similar to the raisable structure <NUM> or <NUM> as described above, that is mounted at the base <NUM>. Alternatively, and such as shown in <FIG>, the arm <NUM> may be mounted at an end of an articulating and/or extending arm <NUM> that is mounted at the wheeled base <NUM>. The raisable structure <NUM> or arm <NUM> raises or extends and lowers or retracts the arm <NUM> and gripping mechanism <NUM> to move the gripping mechanism <NUM> into engagement with the beam for gripping the beam <NUM> from below or from a side of the beam. In use, the gripping mechanism <NUM> would typically grip from below the beam <NUM> due to the presence of plywood and concrete at the top side of the beam <NUM>.

In the illustrated embodiment of <FIG>, the arm <NUM> comprises an extendable and retractable arm having multiple sections that move relative to one another to extend or retract the arm and gripping mechanism <NUM>. As shown in the illustrated embodiment, the sections of the arm <NUM>, when extended, are cantileverly supported relative to the adjacent arm or section. During extension and retraction of the arm <NUM>, the arm sections may move via rollers and brackets at the inner or proximal end of the respective arm section engaging and moving along the adjacent arm section. Such movement may be responsive to actuation of a cable or chain that imparts movement of the distal or outermost arm section relative to the base <NUM>, such as by, for example, pulling the bracket at the inner or proximal end of the arm <NUM> towards the outer or distal end of the adjacent arm section, or such as via rotatably driving the rollers or other suitable means.

The gripping mechanism <NUM> is pivotally mounted at the distal end of the arm <NUM>, which is pivotally mounted at the end of the extendable arm <NUM>, and which is pivotable relative to the arm <NUM> via a hydraulic actuator <NUM> or other actuating means. Optionally, and in reference to <FIG>, the gripping mechanism arm <NUM> may be pivotally mounted at a support structure <NUM> at an upper end of the raisable structure <NUM>, with the support structure <NUM> mounted at an extendable boom <NUM> similar to like elements described above (see, for example, support structure <NUM> and boom <NUM>), such that a detailed discussion of the support structure need not be repeated herein. The gripping mechanism <NUM> may be coupled to another hydraulic actuator <NUM>,or other actuating mean, that extends and retracts to close and open the jaws of the gripping mechanism.

Because the beams may be nailed or otherwise affixed to the formwork, the gripping mechanism <NUM> may also include a rotary actuator <NUM> that rotates the jaws to apply a twisting force at the beam, when the beam is clamped between the jaws, to free the beam for removal. As can be seen in <FIG>, the rotatory actuator <NUM> may comprise a motor, such as a hydraulically operated motor, that rotatably drives a gear 440a that, in turn, rotatably drives a gear 440b at the base of the jaws, such as via a chain or linkage not shown, to rotate the gripping mechanism <NUM> about the longitudinal axis of the actuator <NUM>. After the beam has been broken free from the plywood or formwork and removed, the arm <NUM> and the raisable structure <NUM> or arm <NUM> may be repositioned to lower the removed beam <NUM>. The gripping mechanism <NUM> may be opened to release the lowered beam <NUM> so as to set or drop the beam <NUM> onto the ground surface or other suitable storage location.

Optionally, and such as shown in <FIG>, the gripping mechanism <NUM>' may be rotatably and adjustably mounted at the end of an arm <NUM>' that comprises two or more telescoping arms or sections 437a' that are telescopingly extendable and retractable, such as via a hydraulic actuator or cables or chains or the like disposed within or otherwise along at least one of the telescoping arm sections. In the illustrated embodiment, a proximal end of the telescoping arm sections 437a' is pivotally mounted at a distal end of a base arm 437b', which has a proximal end that is rotatably mounted at the wheeled base <NUM>'. The base arm is pivotally mounted at a rotatable base 437c' that rotates about a generally vertical axis relative to the wheeled base <NUM>', for example such as via a rotary drive device or system at the base, and the base arm 437b' pivots about a generally horizontal axis relative to the base 437c' via extension and retraction of an actuator at the base 437c'. Similarly, the telescoping arms 437a' pivot about a generally horizontal axis relative to the base arm 437b' via extension and retraction of an actuator between the base arm 437b' and the proximal telescoping arm.

Thus, the gripping mechanism <NUM>' can be moved or maneuvered to any location via moving the wheeled unit and then adjusting the angles and orientation of the rotatable base 437c' and arms 437a', 437b'. The gripping mechanism <NUM>' is rotatably mounted at the distal end of the telescoping arms 437a' and can rotate about a pivot axis that is normal to the longitudinal axis of the telescoping arms 437a', such as via a bracket that mounts the gripping mechanism at the distal end of the arm, and the jaws 434a' of the gripping mechanism can also rotate about another pivot axis that is normal to the pivot axis of the bracket at the end of the arm. Thus, the jaws 434a' can be maneuvered to position the jaws 434a' at the beam, whereby the jaws 434a' may be clamped onto the beam for removing the beam.

Optionally, the base unit or wheeled support may have a raisable/lowerable device or structure, with an attaching portion or head at an upper end of the raisable/lowerable device, which is configured for detachable attachment of either the mechanism and retaining mechanism or the gripping mechanism, such that the machine can be adapted for removing plywood from the underside of the concrete slab or ceiling and for removing the support poles and beams from the underside of the concrete slab or ceiling. Thus, a single machine may be used for both removal processes, with the formwork engaging device or mechanism being switched to adapt the machine for the respective process.

As shown in <FIG>, the machine may include a control panel <NUM> that provides the operator with controls to raise and lower the removal device and to extend the device and pivot the device and to grasp and release the formwork, via extension and retraction of the respective actuators or hydraulic cylinders. For example, the control panel <NUM> may include a combination of controls that affect one or more of the raising and lowering of the lift mechanism from the base, the extension and retraction of the boom upon which the formwork-removal device is mounted to and from the lift mechanism, the upward and downward tilt of the formwork-removal device relative to the arm or boom or support structure, and the opening and closing of the gripping mechanism relative to the wedge element or support structure. The control panel <NUM> also provides controls for controlling operation of the wheeled support so the operator can maneuver the wheeled support to a desired location before and/or after the removal device removes formwork. In the illustrated embodiment, the control panel <NUM> includes joystick controls <NUM> for the operator to use to control the head tilt, the boom and the clamp or grasping device. However, it should be understood that the control panel may include push buttons, slide switches, touch enabled screens, or any other element configured to direct the motions of the formwork removing machine.

During operation of the machine, the controls may limit the propel speed of the wheeled support if the scissor lift mechanism is raised, such as, for example, in response to a sensor at the lift mechanism. The controls may also limit the propel speed of the wheeled support if the machine is on an angled drive or support surface, for example such as in response to a level sensor at the wheeled support. The controls may also limit the raising speed of the lift mechanism as it gets close to the ceiling and approaches its working height, for example such as in response to a distance-sensing sensor (such as an ultrasonic sensor or the like) at an upper part of the lift mechanism or other sensor that determines when the lift mechanism is nearing the appropriate working height. The controls may also disable the raise function of the lift mechanism if the machine is at an angled support surface, for example such as in response to a level sensor at the wheeled support.

After the operator has used the formwork removing machine to remove a formwork element, the operator may actuate a home or return button or switch or input at the control panel <NUM> (such as at the end of one of the joysticks or elsewhere at the control panel) to cause the machine to automatically return to its initial or home settings to position the head tilt, boom and clamp to their ready positions for the next removal or stripping cycle. For example, the operator may press and hold a reset push button to begin the sequence that (i) drives the head tilt up function for an adjustable time duration, (ii) drives the boom retract function for an adjustable time duration or until the boom limit switch is activated, and (iii) drives the clamp open for an adjustable time duration, whereby the boom will be retracted and the head will be tilted upward with the jaws open, so as to be ready for the next removal or stripping cycle. When the reset sequence is active, the sequence can be stopped by pressing the reset push button again. Actuation of the head tilt, boom or clamp joystick to a degree that is greater than an adjustable threshold will also stop the sequence. Such joystick commands may be ignored below this threshold such that the return or home sequence is not stopped if a slight bump or similar occurs at any of the joysticks.

Optionally, the formwork-removal device or the beam-removal device may be selectively attached to the wheeled, motorized machine or base, and are selectively positioned at an operating position for performing the desired or selected task. That is, the mechanisms may be interchanged at a common or universal base <NUM> or <NUM> or <NUM> and/or raisable/lowerable or extendable/retractable structure <NUM> or <NUM> or <NUM> or <NUM> at the base. For example, once the slab has hardened, workers may attach the beam-removal device to the raisable structure of the wheeled base to disassemble and remove the beams supporting the formwork. Once the beams have been removed, workers may remove the beam-removal device and attach the formwork-removal device to the raisable structure of the wheeled base to remove the formwork or plywood from the slab. Optionally, the beam removal mechanism may be mounted at one end of the raisable structure and the formwork-removal device may be mounted at the opposite end of the raisable structure, such that a single machine is selectively operated to perform the desired operation.

During operation of the machine, an operator may remotely drive the wheeled base, fitted with beam-removal device, at the worksite, such as via a remote controller that is operable to control driving and steering of the wheels, extension/retraction of the raisable structure, and pivoting/rotating/clamping/unclamping of the gripping device. The operator remotely controls the beam-removal device to sequentially remove each formwork beam by gripping each beam from below, rotating the beam to be free from nails or other attachments and from the plywood, repositioning the beam and releasing the beam at a targeted location, such as onto a trailer towed by the wheeled base. As needed, the operator maneuvers the wheeled, motorized machine between remaining shoring posts to be able to access the next beam in the sequence. Optionally, the beam-removal device may also be used to remove some of the vertical posts by grasping the posts and (such as after the posts are adjusted to be lowered from the beams) lifting and moving the posts to a desired or targeted location.

After the beams are removed, the operator may remotely control the wheeled machine to transport the beams, on the trailer or other storage platform or the like, away from the worksite. Operators may then fit or adapt the wheeled machine with the formwork-removal device and remotely control the wheeled machine and the formwork-removal device to sequentially remove the formwork or plywood from the underside of the concrete slab or ceiling structure. The operator, using the remote controller, may extend the raisable structure so that the wedge mechanism contacts the hardened slab, then drive the wheeled, motorized machine forward, causing the wedge mechanism to engage with the plywood and separate part of the plywood from the concrete slab. As the plywood is freed by the wedge mechanism, the operator remotely controls the gripping mechanism to hold and retain the removed plywood. The operator then remotely operates the wheeled, motorized machine and the formwork-removal device to lower and position the plywood and release the plywood at a targeted location, such as onto the trailer, if applicable.

The operator control of the machine may be achieved via a wireless remote controller, which has multiple controls or inputs to allow the operator to control various motors and actuators of the machines. For example, the machine may have a gasoline powered engine that powers or drives a hydraulic pump for providing pressurized hydraulic fluid to hydraulic motors and hydraulic actuators of the machine. For example, the controller may control the machine to hydraulically drive the steering mechanism and the wheel drive motors to maneuver the base and the machine over the support surface or floor, and may separately control one or more hydraulic actuators to raise/lower or extend/retract the support structure at the base to raise/lower the device, such as the plywood removing device or the beam removing device, attached at the upper end of the support structure. The controller may also control one or more hydraulic actuators to extend or pivot or articulate the device and to operate the device to remove and move the plywood or beam.

Thus, a method for removing formwork from underneath a cured concrete slab includes providing a wheeled base movable on and supported at a support structure, a raisable and lowerable structure disposed on the wheeled base, and a formwork-removal device attached to the raisable and lowerable structure. The formwork-removal device comprises (i) an arm extending from the raisable and lowerable structure, (ii) at least one wedge element disposed at a distal end of the arm, and (iii) a formwork-retaining mechanism. The method includes moving the wheeled base along the support structure to position the machine below or near formwork to be removed from the ceiling above the machine, and adjusting the raisable and lowerable structure adjusted to raise the wedge element and to position the wedge element at and in engagement with the formwork and an underside of the concrete slab. With the raisable and lowerable structure adjusted to raise the wedge element and with the wedge element positioned to engage the formwork and an underside of a concrete slab, the method includes moving the wedge element relative to the formwork to apply a separating force to separate part of the formwork from the underside of the concrete slab. With the wedge element engaged with the formwork and the underside of the concrete slab, the method includes operating the formwork-retaining mechanism to grasp the part of the formwork that is separated from the underside of the concrete slab to retain the formwork at the formwork-removal device. With the formwork grasped by the formwork-retaining mechanism, the method includes lowering the raisable and lowerable structure to remove the formwork from the underside of the concrete slab. The machine may be moved to a drop-off location where the formwork-retaining mechanism is operated to release the part of the formwork to drop the removed formwork at the targeted drop-off location.

Also, a method for removing beams from underneath formwork at an underside of a cured concrete slab includes providing a wheeled base movable on and supported at a support structure, a raisable and lowerable structure disposed on the wheeled base, and a beam-removal device coupled to the raisable and lowerable structure. The beam-removal device comprises a beam-gripping mechanism. The method includes moving the wheeled base along the support structure to position the machine below or near a beam to be removed from the ceiling above the machine, and adjusting the raisable and lowerable structure adjusted to raise the beam-removal device and to position the beam-removal device at the beam at an underside of the concrete slab. With the raisable and lowerable structure raised to position the beam-removal device at the beam that supports the formwork at the underside of the concrete slab, the method includes operating the beam-gripping mechanism to grasp the beam and, with the beam grasped by the beam-gripping mechanism, operating the machine to remove the beam from the formwork (such as by twisting and/or lowering the beam-gripping mechanism with the beam grasped thereat). With the removed beam grasped by the beam-retaining mechanism, the method includes lowering the raisable and lowerable structure. The machine may be moved to a drop-off location where the beam-retaining mechanism is operated to release the removed beam to drop the beam at the targeted drop-off location.

Optionally, the machine may be operated to facilitate installation of formwork, before the concrete is placed and cured. For example, the machine may lift or raise beams into position at the upper ends of the posts, and/or the machine may lift or raise plywood panels into position on top of the beams prior to pouring the concrete slab. The operator may remotely control the beam-removal device to sequentially install each formwork beam by gripping each beam from its stored location and raising/repositioning the beam to engage with previously installed beams or shoring posts, then releasing the gripping mechanism. Similarly, the operator may remotely control the formwork-removal device to hold the plywood formwork in its gripping mechanism and raise/reposition the plywood formwork to its installation point for installation.

The positioning of the beams and/or plywood panels at the upper ends of the posts may be responsive at least in part to a laser leveling device to ensure that the beams and plywood are at the appropriate height and are level. Such laser leveling devices utilize a laser plane generator and laser receivers, which may be disposed at the beam or formwork removal device and/or at the raisable/lowerable structure to determine when the laser receiver(s) is at a particular height or level corresponding to the generated laser plane, which effectively sets the height of the device at an appropriate or selected height for its particular function, and may utilize aspects of the systems described in <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT> and/or <NUM>,<NUM>,<NUM>. Optionally, during the removal process or processes, the positioning of the removal devices may be responsive at least in part to such a laser leveling system.

Claim 1:
A machine (<NUM>,<NUM>) for removing formwork from underneath a cured concrete slab, the machine comprising:
a wheeled base (<NUM>,<NUM>) movable on and supported at a support structure
a raisable and lowerable structure (<NUM>,<NUM>) disposed on the wheeled base
a formwork-removal device (<NUM>,<NUM>) attached to the raisable and lowerable structure the formwork-removal device comprising (i) an arm (<NUM>,<NUM>,<NUM>,<NUM>) extending from the raisable and lowerable structure, (ii) at least one wedge element (<NUM>,<NUM>) disposed at a distal end of the arm, and (iii) a formwork-retaining mechanism (<NUM>,<NUM>);
wherein the raisable and lowerable structure is adjusted to raise the wedge element and when the wedge element is positioned to engage the formwork and an underside of a concrete slab, the wedge element is moved relative to the formwork to apply a separating force to separate part of the formwork from the underside of the concrete slab;
characterized in that, when wedge element is engaged with the formwork and the underside of the concrete slab, the formwork-retaining mechanism is operated to grasp the part of the formwork that is separated from the underside of the concrete slab to retain the formwork at the formwork-removal device; and
when the formwork is grasped by the formwork-retaining mechanism, the raisable and lowerable structure is lowered to remove the formwork from the underside of the concrete slab.