Flotation machine having pan support structure configured for conforming the shape of a float pan
11535987 · 2022-12-27
Assignee
Inventors
Cpc classification
E01C19/405
FIXED CONSTRUCTIONS
E04F21/247
FIXED CONSTRUCTIONS
International classification
E01C19/42
FIXED CONSTRUCTIONS
Abstract
A support structure for a float pan for floating a concrete surface provides an interface between the float pan and a rotating machine. The support structure is characterized by a hub configured for concentric attachment to a rotor, and by trusses that extend radially from the hub, each providing a float pan contact surface and means for attachment to the float pan. Perimetric bracing links the trusses about the perimeter of the support structure. A machine similar to a walk-behind or ride-on trowel but without rotor blades, may incorporate the support structure and operate as a dedicated power flotation machine. Under weight of the machine, the contact surfaces of the trusses conform the float pan to a desired shape or radius of curvature for optimizing a flotation process.
Claims
1. A machine for floating a concrete surface, comprising: a rigid frame adapted to be disposed over said concrete surface; means attached to the rigid frame for providing motive power to said machine; at least one rotatable rotor assembly attached to the rigid frame and configured for converting the motive power into rotational motion; and a float pan support structure rotatably coupled to the at least one rotor assembly and configured for rotatable attachment to a float pan, said float pan having a conformable shape configured to frictionally contact said concrete surface and support said rigid frame thereabove, said support structure configured for conforming the shape of the float pan; wherein the float pan support structure further comprises: a hub having a rotational axis and configured for concentric attachment to the rotor assembly; a plurality of trusses, each truss extending radially from the hub and each truss having a float pan contact surface, wherein one or more of the trusses includes means for attachment to the float pan; and perimetric bracing linking two or more of the trusses.
2. The machine of claim 1, wherein the hub further comprises a flange positioned concentrically with respect to the axis; and a truss attachment surface displaced radially from the axis along a perimeter of the flange, wherein the truss attachment surface circumferentially encloses the flange.
3. The machine of claim 2 wherein the flange comprises a planar surface normal to the axis and wherein the truss attachment surface extends perpendicularly from the planar surface of the flange.
4. The machine of claim 2 wherein the truss attachment comprises a cylinder.
5. The machine of claim 2 wherein at least one of the trusses comprises a pair of truss arms.
6. The machine of claim 2 wherein the truss arms of the at least one truss are connected together at a distal end of the at least one truss.
7. The machine of claim 2 wherein the plurality of trusses are angularly spaced about the axis of the hub at regular intervals.
8. The machine of claim 7 wherein the plurality of trusses comprises eight trusses.
9. The machine of claim 2 wherein the float pan attachment means comprises a hole defined through the truss.
10. The machine of claim 2 wherein the float pan contact surface of each truss has a form identical to the float pan contact surface of every other truss.
11. The machine of claim 2 wherein the float pan contact surface of at least one truss is substantially fully flat.
12. The machine of claim 2 wherein the float pan contact surface of at least one truss is substantially fully curved in a radial direction.
13. The machine of claim 2 wherein the float pan contact surface of at least one truss is partially flat in a radial direction and partially curved in the radial direction.
14. The machine of claim 2 wherein the float pan contact surface of at least one truss is substantially fully curved in a radial direction and wherein a proximal end of the at least one truss is recessed from the float pan contact surface in an axial direction.
15. The machine of claim 2 wherein the float pan contact surface of at least one truss is partially flat in a radial direction and partially curved in the radial direction and wherein a proximal end of the al least one truss is recessed from the float pan contact surface in an axial direction.
16. The machine of claim 2 wherein at least one of the trusses at its distal end comprises a notch configured for engaging the perimetric bracing.
17. A machine for floating a concrete surface, comprising: a rigid frame adapted to be disposed over said concrete surface; means attached to the rigid frame for providing motive power to said machine; at least one rotatable rotor assembly attached to the rigid frame and configured for converting the motive power into rotational motion; a float pan support structure rotatably coupled by a hub to the at least one rotor assembly and configured for rotatable attachment to a float pan, said float pan having a conformable shape configured to frictionally contact said concrete surface and support said rigid frame thereabove, said support structure configured for conforming the shape of the float pan; a plurality of trusses, each truss extending radially from the hub and each truss having a float pan contact surface, wherein one or more of the trusses includes means for attachment to the float pan; and perimetric bracing linking two or more of the trusses; wherein the float pan contact surface of at least one truss is substantially fully flat and wherein a proximal end of the least one truss is recessed from the float pan contact surface in an axial direction.
18. A machine for floating a concrete surface, comprising: a rigid frame adapted to be disposed over said concrete surface; means attached to the rigid frame for providing motive power to said machine; at least one rotatable rotor assembly attached to the rigid frame and configured for converting the motive power into rotational motion; a float pan support structure rotatably coupled by a hub to the at least one rotor assembly and configured for rotatable attachment to a float pan, said float pan having a conformable shape configured to frictionally contact said concrete surface and support said rigid frame thereabove, said support structure configured for conforming the shape of the float pan; a plurality of trusses, each truss extending radially from the hub and each truss having a float pan contact surface, wherein one or more of the trusses includes means for attachment to the float pan; and perimetric bracing linking two or more of the trusses; wherein the hub comprises an inner wall having a slope is configured to receive a centering bracket mounted on the float pan, and while receiving the centering bracket, to urge the float pan into axial alignment with the support structure.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Other systems, methods, features and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims. Component parts shown in the drawings are not necessarily to scale, and may be exaggerated to better illustrate the important features of the invention. Dimensions shown are exemplary only. In the drawings, like reference numerals may designate like parts throughout the different views, wherein:
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DETAILED DESCRIPTION OF THE INVENTION
(16) The present invention discloses an innovation for power flotation machine. A power flotation machine according to the invention provides a specialized pan support structure as a direct mechanical interface between rotor and float pan. Such a machine can be operated exclusively as a flotation machine, without intermediate attachment of the float pan to trowel blades. Advantageously, the specialized pan support structure when under load conforms the shape of the float pan to an optimal, desired shape during concrete floating operations. The invention may be applied to both walk-behind and ride-on machines. For purposes of illustration only, the invention is described herein in the context of a ride-on embodiment.
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(18) Machine 10 is designed for floating a concrete surface. Machine 10 includes a rigid frame 18 that is adapted to be disposed over a planar concrete surface, and that provides structural support for all components of the machine. Machine 10 includes means attached to the rigid frame 18 for providing motive power to said machine, such as an internal combustion engine, an electric motor, a battery, hydraulic drives, or any combination of the foregoing. Machine 10 also includes at least one but preferably two rotatable rotors 14 that are each attached to the rigid frame 18 and configured for converting the motive power into rotational motion. Machine 10 may include a protective cagework 20 that is attached to the rigid frame 18 and disposed over and about a portion of each pan support structure 12. For illustrative purposes only, cagework 20 is omitted from
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(20) The number of trusses 30 that compose the plurality can vary. In the embodiment disclosed herein, a total of eight trusses 30 are shown as an example. The trusses 30 are shown angularly spaced about the axis 28 of the hub 22 at regular intervals, i.e. each truss 30 is angularly offset from an adjacent truss 30 by 45 degrees. Where the trusses 30 are spaced at regular intervals, the angular offset will be a function of the total number of trusses. In other embodiments, it is contemplated that trusses 30 may be spaced at irregular intervals, or at a combination of regular and irregular intervals. For example, an alternative embodiment of a float pan support structure 12 may have a total of six trusses 30, with a first set of three trusses on one half of the support structure and a second set of three trusses on the other half of the support structure, directly opposite the first set of three trusses, wherein the middle truss of each set is spaced from its two adjacent trusses by alpha degrees and from the one opposite middle truss by 180 degrees. Each of the other two trusses in a set is spaced from its two adjacent trusses by alpha degrees and by (180-2*alpha) degrees. Skilled artisans will recognize that there are many different configurations, using different spacing angles and different numbers of trusses, for angular spacing plural trusses 30 about the axis 28 of the hub 22 without departing from the scope of the invention. It is also possible to replace the plural trusses with a singular support, in circular, conical, or spherical form, that spans from hub 22 to the perimeter of the support structure 12; however such as design has the disadvantage of adding excessive weight to the assembly and adding unnecessarily to manufacturing costs.
(21) Referring again to
(22) In another embodiment of the invention, one or more of the trusses 30 may each comprise a pair of truss arms, 30a and 30b, as shown in the figures. Each pair of truss arms 30a-30b may be identical in form, but if not identical are preferably similar in form. For any pair of truss arms 30a-30b, at the proximal end each truss arm of the pair may be angularly spaced from the other truss arm of the pair, while their distal ends be attached together, so that each pair of truss arms 30a-30b forms a triangular wedge. Where the distal ends come together, the truss arms 30a-30b may be welded together or attached by other means such as conventional fasteners.
(23) Whether a truss 30 consists of a singular arm, or a pair of truss arms 30a-30b, the lower surface of the truss 30 provides a pan contact surface 45 that when pressed against a float pan 16, conforms the upper surface of the float pan 16 to the shape of the pan contact surface 45. This will be described in further detail below with reference to
(24) The float pan support structure 12, comprising hub 22, trusses 30, and perimetric bracing 32, is configured for rotatable attachment to the float pan 16. Rotatable attachment means that support structure 12 is attachable to the float pan 16 so that when a rotor 12 of machine 10 rotates, the rotational power will be transmitted by the support structure to the float pan and cause the float pan to rotate cooperatively with the rotor. Preferably, the rotatable attachment of the support structure 12 to the float pan 16 enables both components to rotate at the same frequency and without slippage. In this respect, float pan support structure provides a cooperative connection interface between each float pan 16 and each rotor 12. During operation, the weight of machine 10, which can be in excess of 2500 lbs, presses the float pan 16 downward onto a concrete surface while rotating the float pan. The float pan 16 is formed from material such as aluminum, magnesium, or soft steel, into a conformable shape configured to frictionally contact the concrete surface and support the frame of machine 10 above the concrete surface. According to the invention, the float pan support structure 12 is configured for conforming the shape of the float pan 16 into a desired shape for optimizing a concrete floating process under these conditions.
(25) In the exploded view of
(26) When the float pan 16 is axially aligned with the support structure 12, the two components may be rotatably attached. Means for effecting such rotatable attachment may include one or more of a hole 36 defined through a truss 30, the truss itself, a pair of connecting brackets 38, and a fastener (not shown) such as a hex-head bolt and nut, or a cotter pin. For example, the rotatable attachment may be achieved by angularly aligning the support structure 12 and float pan 16 so that when engaged, two or more trusses 30 abut the surface of the float pan between a pair of connecting brackets 38. In one embodiment, spacing between any two brackets of a pair of connecting brackets 38 may be about 1.7 in., and there may be multiple pairs of connecting brackets, preferably angularly spaced to receive trusses 30. For example, each pair may be angularly spaced from an adjacent pair by about 90 degrees, as shown. Fasteners may be run through bolt holes in brackets 38 and through one or more holes 36 in a truss 30 to lock the float pan to the support structure. According to the invention, such rotatable attachment may allow a minor amount of shifting to occur between the support structure and float pan in the horizontal plane, so long as the float pan is attached in such a way to substantially maintain its cooperative alignment and rotation with the support structure.
(27) In a more elegant embodiment of the invention, a support structure for a float pan may comprise a hub that is configured for concentric attachment directly to a rotor, and a means for attaching the hub directly to the float pan. Direct attachment between the hub and a rotor means that surfaces of the two attached components abut one another. In one implementation, the structure for the directly attaching means may comprise hardware such as brackets and fasteners attached to both the hub and the float pan that when fastened cause the direct attachment. In another implementation, the directly attaching means may comprise a magnetic force, provided by electromagnetic induction or by a permanent magnet. The permanent magnet may be formed as an integral part of the hub, or the entire hub may be magnetized. In any of the foregoing embodiments for direct attachment between hub and float pan, the directly attaching means may be configured for concentrically aligning the float pan to the hub.
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(29) In an embodiment of a float pan not shown in the figures, a float pan may be formed along its perimeter with integral perimetric bracing. The integral perimetric bracing may be similar in form to perimetric bracing 32 shown and described herein. Alternatively, the integral perimetric bracing may be a circular (or other shaped) rim running along the upper perimeter of the float pan. Means for attaching trusses 30 to the integral perimetric bracing may be provided on the integral perimetric bracing itself, or on the distal ends of braces 30, or on both components. The structure of the attaching means should allow for convenient removal of the float pan, and may comprise slots, brackets, fasteners, cotter pins, alignments holes, or other locking or engagement devices. In any of these embodiments, the perimetric bracing 32 is absent from the float pan support structure 12.
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(39) Exemplary embodiments of the invention have been disclosed in an illustrative style. Accordingly, the terminology employed throughout should be read in a non-limiting manner. Although minor modifications to the teachings herein will occur to those well versed in the art, it shall be understood that what is intended to be circumscribed within the scope of the patent warranted hereon are all such embodiments that reasonably fall within the scope of the advancement to the art hereby contributed, and that that scope shall not be restricted, except in light of the appended claims and their equivalents.