CONCRETE SCREED

Abstract

A concrete screed includes a pair of longitudinal supports having proximal ends that are located opposite distal ends, where the proximal ends are pivotably mounted to an operating machine, such as a skid steer, such that the longitudinal supports extend in a longitudinal direction from the skid steer. A pair of cross members and an end member extend between the longitudinal supports, where the end member is located near the distal ends of the longitudinal supports. A screed blade is pivotably mounted to the end member at a single pivot point, and extends outboard of the longitudinal supports in opposing lateral directions perpendicular to the longitudinal direction. A support platform extends between the cross members and may support a compacting machine. If desired, the screed blade may flexed and/or vibrated during use.

Claims

1. A concrete screed comprising: a pair of longitudinal supports having respective proximal end portions and distal end portions, said proximal end portions configured to be pivotably coupled to an operating machine; an end member extending between said longitudinal supports proximate said distal end portions; a support platform coupled to said longitudinal supports; and a screed blade pivotably coupled to said end member at a pivot point, said screed blade extending laterally outboard of said longitudinal supports; wherein said screed blade is vibratable by placing a compacting machine on said support platform and activating the compacting machine.

2. The concrete screed of claim 1, further comprising a pair of cross members extending between said longitudinal supports and extending along forward and rearward portions of said support platform.

3. The concrete screed of claim 2, wherein said cross members cooperate with portions of said longitudinal supports to define a machine-receiving cavity above said support platform.

4. The concrete screed of claim 1, wherein said support platform comprises a sheet panel.

5. The concrete screed of claim 1, wherein said screed blade is pivotably coupled to said end member about a longitudinal axis.

6. The concrete screed of claim 5, wherein said screed blade is pivotably coupled to said end member via a single pin at the longitudinal axis, wherein said single pin is manually removable to decouple said screed blade from said end member.

7. The concrete screed of claim 5, wherein said longitudinal supports are pivotably coupled to the operating machine via a pair of pins that are manually removable to decouple said longitudinal supports from the operating machine.

8. The concrete screed of claim 7, further comprising a pair of flexible elongate supports coupled to and extending between respective ones of said longitudinal supports and respective opposite end portions of said screed blade.

9. The concrete screed of claim 1, wherein said screed blade is laterally extendable and retractable to increase and decrease its width.

10. The concrete screed of claim 9, further comprising a pair of extension members configured to be coupled to opposing ends of said screed blade.

11. The concrete screed of claim 10, wherein the width of said screed blade is adjustable by selectively coupling said extension members to said screed blade at selected ones of a plurality of spaced-apart locations.

12. The concrete screed of claim 1, wherein said screed blade is linearly movable by the operating machine and pivotable about a longitudinal axis in a laterally-oriented vertical plane.

13. The concrete screed of claim 1, further in combination with said compacting machine, wherein said compacting machine comprises a self-contained portable compacting machine.

14. The concrete screed of claim 1, further comprising a brace structure coupled to said screed blade and extending upwardly from said screed blade, said brace structure configured to provide structural support to said screed blade.

15. The concrete screed of claim 14, wherein said brace structure comprises: a middle brace member spaced above a central region of said screed blade; and a pair of diagonal brace members coupled to respective outboard end portions of said middle brace member and to respective end portions of said screed blade; wherein said diagonal brace members extend laterally outwardly and downwardly from said outboard end portions of said middle brace member to said screed blade.

16. The concrete screed of claim 15, wherein said brace structure further comprises a pair of upright brace members coupled to said respective outboard end portions of said middle brace member and extending downwardly to couple to said screed blade.

17. The concrete screed of claim 15, further comprising a linear actuator at said middle brace member, wherein said middle brace member is laterally extendable and retractable by said linear actuator to impart flexing forces to said screed blade via said diagonal brace members.

18. A concrete screed comprising: a longitudinal support having a proximal end portion and a distal end portion, said proximal end portion configured to be pivotably coupled to an operating machine; a screed blade pivotably coupled to said longitudinal support proximate said distal end portion, said screed blade extending outboard of said longitudinal support in opposing lateral directions and pivotable about a longitudinal axis; and a brace structure coupled to said screed blade, said brace structure comprising: a middle brace member spaced above a central region of said screed blade; an upright brace member having a lower portion coupled to said screed blade and an upper portion coupled to said middle brace member; and a pair of diagonal brace members extending laterally outward and downward from opposite ends of said middle brace member, and coupled to said screed blade at respective locations spaced laterally outboard of said distal end portions of said longitudinal supports.

19. The concrete screed of claim 18, further comprising an actuator at said middle brace member, wherein said middle brace member is laterally extendable and retractable by said actuator to impart flexing forces to said screed blade via said diagonal brace members, and wherein said screed blade is configured to assume a concave-down curved shape in response to extension of said middle brace member by said actuator.

20. The concrete screed of claim 18, wherein said longitudinal support comprises a pair of spaced-apart lateral supports, said concrete screed further comprising a support platform coupled to said longitudinal supports, wherein said screed blade is vibratable by placing a compacting machine on said support platform and activating the compacting machine

Description

BRIEF DESCRIPTIONS OF THE DRAWINGS

[0014] FIG. 1 is a front perspective view of a concrete screed shown mounted to a skid steer and supporting a compacting machine on a support platform;

[0015] FIG. 2 is another front perspective view of the concrete screed of FIG. 1, where a portion of the screed blade is disassembled, portions removed, and the compacting machine is removed from the support platform;

[0016] FIG. 3 is an rear end perspective view of the concrete screed of FIG. 1;

[0017] FIG. 4 is a rear perspective view of a frame of the concrete screed of FIG. 1;

[0018] FIG. 5 is a front perspective view of a frame mount of the concrete screed of FIG. 1;

[0019] FIG. 6 is a front perspective view of an end member of the frame of the concrete screed of FIG. 1, where the screed blade is pivotably mounted to the end member via a pin;

[0020] FIG. 7 is a front-right perspective view of another concrete screed shown mounted to a skid steer;

[0021] FIG. 8 is an enlarged view of the area designated VIII in FIG. 7;

[0022] FIG. 9 is a front perspective view of the concrete screed and skid steer of FIG. 7, with the screed blade in a flat or planar shape; and

[0023] FIG. 10 is another front perspective view of the concrete screed and skid steer of FIG. 7, with the screed blade in a concave-down curved shape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Referring now to the drawings and the illustrative embodiments depicted therein, a concrete screed 20 is adapted to be pivotably mounted to an operating machine such as skid steer 22 (FIGS. 1 and 2), and pulled across a concrete surface by the skid steer 22. A frame mount 24 is mountable to skid steer 22, the frame mount 24 including a pair of pockets 26 (FIG. 5) for receiving a pair of longitudinal supports or support members 28 of a frame 27, the support members 28 being pivotably coupled to the frame mount 24 by proximal pins 30. A compacting machine 32 is optionally supported on a support platform 34 of frame 27, where support platform 34 is secured between a pair of cross members 35 extending between support members 28. A longitudinally-aligned distal pin 36 is used to pivotably mount a telescopically-adjustable screed blade 38 to an end member 40 extending between support members 28 (FIG. 6). Screed blade 38 is pivotable about a longitudinal axis (roll axis) that extends through distal pin 36, while support members 28 are pivotable about a horizontal lateral axis (pitch axis) defined through proximal pins 30 (FIG. 3). As a result, screed blade 38 is movable in forward and backward directions by driving skid steer 22, is pivotable up and down about proximal pins 30, and is pivotable left and right about the roll or longitudinal axis to allow screed blade 28 to conform to a concrete surface during a screeding operation. The concrete may also be compacted during the screeding operation by activating compacting machine 32 on support platform 34, such that vibrations generated by compacting machine 32 are transferred through screed blade 38 to the concrete surface.

[0025] With further reference to FIG. 4, support members 28 are elongated steel beams having a rectangular cross section, and extend parallel to one another in the forward (longitudinal) direction once secured to frame mount 24. Cross members 35 are secured between support members 28 to not only provide support to support platform 34, but to also reinforce and strengthen concrete screed 20. Support platform 34 is generally a planar rectangular surface that is recessed below an upper surface 27a of frame 27 (FIG. 2). Support members 28 help retain compacting machine 32 on platform 34, such that compacting machine 32 is surrounded by support members 28 and portions of support members 28 at the perimeter of platform 34. Support platform 24 is located closer to distal ends 28b of support members 28 than proximal ends 28a to ensure that, during use, the weight and vibrations of compacting machine 32 are primarily transferred to screed blade 38 as opposed to skid steer 22.

[0026] A pair of through-holes or mounting holes 42 are defined near the proximal end 28a of each support member 28 (FIG. 4), where each pair of mounting holes 42 is configured to receive one of the proximal pins 30 to pivotably mount support members 28 to frame mount 24. End member 40 is secured between distal ends 28b of support members 28, and also secured between a pair of plates 44. (FIG. 6). Plates 44 define through-holes or mounting holes 45 (FIG. 6) that are aligned with one another, and that are configured to receive distal pin 36 to pivotably mount screed blade 38 to support members 28. A pair of securing elements in the form of enclosed loops 46 (FIGS. 3 and 4) are attached to outboard sides 28c of support members 28, where each loop 46 may serve as a handle for manually moving frame 27 when it is not in use, and may also receive and secure one end of a reinforcement member in the form of a respective elongate support such as a cable, chain, or straps 48 (FIGS. 3, 7, 9, and 10) when in use. A second pair of securing elements or enclosed loops that may receive and secure the opposite ends of straps 48 are attached to a central screed member 50 of screed blade 38. When secured between frame 27 and screed blade 38, straps 48 provide additional stability and support to screed blade 38 while screed blade 38 is being pulled by skid steer 22 during the screeding process.

[0027] Central screed member 50 defines a pair of mounting holes that may be aligned with the mounting holes 45 of plates 44 (FIG. 6) to pivotably mount central screed member 50 to support members 28. As shown in FIGS. 1 and 3, a brace structure 54 provides further support and reinforcement to screed blade 38, and includes upright brace members 56 extending upward from screed blade 38 to support a middle brace member 58 that is connected to upper end portions of upright brace members 56 and between inboard end portions of diagonal brace members 60 that extend diagonally outboard and down to couple to opposite side portions of screed blade 38. Brace structure 54 may also provide further support to compacting machine 32, for example, by physically blocking compacting machine 32 from falling off concrete screed 20 in a forward direction (refer to FIGS. 1 and 3) and/or by providing additional structure to which compacting machine 32 may be secured, for example, via a rope or tie-down strap.

[0028] Referring now to FIGS. 2 and 5, frame mount 24 includes a mounting plate 62 that is mountable to skid steer 22. Receiving pockets 26 extend in the forward direction from mounting plate 62. A lower support structure 64 reinforces and strengthens frame mount 24, and includes a frame cross member 66 that extends between frame side members 68. In particular, lower support structure 64 provides additional support for a substantial portion concrete screed 22 including frame 27, screed blade 38, and optionally compacting machine 32, when support members 28 are received in pockets 26. Each pocket 26 is defined by a pair of spaced-apart pocket side walls 70 that are parallel to one another, and that each define mounting holes 72 that are laterally aligned with one another, for receiving proximal pins 30 and thereby coupling the respective support members 28 to pocket side walls 70 as shown in FIG. 2.

[0029] Concrete screed 20 may be readily assembled by hand and mounted to skid steer 22, as well as many other self-propelled equipment and/or vehicles. In order to do so, frame mount 24 may first be mounted to skid steer 22, for example, via one or more bolts and/or physical engagement between one or more surfaces of skid steer 22 and frame mount 24. Frame 27 may then be pivotably mounted to frame mount 24 by inserting proximal ends 28a of support members 28 into pockets 26 such that mounting holes 42 of support members 28 are aligned with mounting holes 72 of pocket side walls 70. Proximal pins 30 may then be inserted through the aligned mounting holes 42 and 72 to thereby pivotably couple frame 27 to frame mount 24. Mounted in this fashion, frame 27 is pivotable about a lateral axis such that frame 27 is pivotable up and down in a vertical plane oriented in the longitudinal direction, extending forward of frame mount 24. This allows for the operator to lower the arms of the skid steer 22 until the screed blade 38 rests atop the wet concrete and/or concrete forms surrounding the wet concrete, while the frame's support members 28 are free to float by pivoting upwardly in receiving pockets 26 as the screed blade 38 is drawn horizontally across the wet concrete.

[0030] Central screed member 50 may be placed between plates 44 such that the mounting holes of central screed member 50 are aligned with the mounting holes 45 of plates 44. Once the mounting holes of central screed member 50 and plates 44 are aligned, distal pin 36 may be inserted through the mounting holes to pivotably mount screed blade 38 to frame 27 at a single pivot point (at distal pin 36) and/or along a single longitudinal pivot axis oriented in the longitudinal direction. Once mounted in this fashion, screed blade 38 is pivotable about a longitudinal axis such that screed blade 38 is pivotable in a laterally-oriented vertical or upright plane. Therefore, screed blade 38 may be moved across an uncured concrete surface in a substantially horizontal motion perpendicular to the laterally-oriented vertical plane as discussed above, while simultaneously being capable of pivoting in the laterally-oriented vertical plane, thereby allowing screed blade 38 to better conform to concrete forms and/or remain flat against a concrete surface during the screeding process. As previously noted, compacting machine 32 may also be activated to produce vibrations that are transferred through screed blade 38 to the uncured concrete. The added vibrational motion of screed blade 38 may help to release trapped air bubbles and pockets in the uncured concrete and therefore compact the concrete into a denser state, to improve the ultimate strength and durability of the concrete after the concrete cures and hardens. It should be appreciated that other types of machines or devices could be incorporated into or secured to a concrete screed to impart vibrational motion to screed blade 38, without departing from the spirit and scope of the present invention. However, in the illustrated embodiment the compacting machine 32 is illustrated as a self-contained portable unit with handle and controls that allow it to be manually moved across ground surfaces of any type (e.g., uncured concrete, gravel, sand, soil) for leveling, compacting, or smoothing. Such compacting machines are commonly used to prepare ground surfaces prior to pouring concrete, and so are often readily available to concrete work crews who would later be expected to use concrete screed 20 for shaping and/or leveling the uncured concrete.

[0031] The width of screed blade 38, which is the length of screed blade 38 in the lateral direction, is telescopically adjustable according to the preference of an operator of concrete screed 20. Central screed member 50 and extension screed members 52 may be slidably coupled to one another, for example, by sliding a portion of extension screed 52 within a hollow interior of central screed member 50. Central screed member 50 and screed extension members 52 define various through-holes that may be aligned with one another in different positions to allow the position of extension members 52 to overlap with central screed member 50 by varying amounts. Once the through-holes of central screed member 50 and extension members 52 are aligned with one another such that extension members 52 extend laterally outboard away from central screed member 50 by a desired amount, pins, fasteners, or the like may be inserted through the through-holes to secure central screed member 50 and screed extension members 52 together. Extension members 52 may also be removed entirely from screed blade 38, such that screed blade 38 would be only the width of central screed member 50. Furthermore, additional screed extension members may be added to screed blade 38 in a similar fashion as described above with regard to coupling screed extension members 52 to central screed member 50. It is further envisioned that a telescoping mechanism utilizing linear actuators (e.g., screw drives, hydraulic or pneumatic pistons, rack-and-pinion) may be used to extend and retract extension members 52 relative to central screed member 50.

[0032] Concrete screed 20 may be disassembled and arranged into a compact configuration for storage or transport, such as on a trailer that used to transport skid steer 20 and/or compacting machine 32. For example, the overall height of screed 20 from the top of middle brace 58 to the bottom of central screed member 50 may be less than the track width (distance between inboard edges of tires or tracks) of skid steer 22 so that all components of screed 20 can be laid atop a flatbed trailer and the skid steer 22 parked and secured directly over the disassembled screed 20, thus utilizing the space under skid steer and between its wheels or tracks, for storage of screed 20 during transport or when not in use.

[0033] As a result, concrete screed 20 may be conveniently transported to and around a construction site along with other equipment used for the screeding process, and may have a sufficiently low profile so as to fit beneath the skid steer 20 on the trailer. Additionally, proximal pins 30 and distal pin 36 are designed to be manually insertable and removable to and from the mounting holes discussed above, to allow for easy assembly and disassembly of substantial portions of concrete screed 20 without the need for tools. In particular, screed blade 38 may be readily coupled and de-coupled from frame 27 via a single distal pin 36, while supporting members 28 may be coupled and de-coupled from frame mount 24 via respective proximal pins 30. It should be appreciated that the various members and components of a frame, frame mount, and/or screed blade may vary in accordance with the present invention. For example, one or more members may be omitted from a concrete screed, one or members may be solid rather than hollow, and one or more members may have varying geometry such as a cylindrical geometry.

[0034] Optionally, and as shown in FIGS. 7-10, middle brace member 58 can be replaced with an extendable and retractable middle brace member 158 that is made up of two tubular outboard sections 158a and a middle section 158 that is telescopingly received in the open inboard ends of the outboard sections 158a. As best shown in FIG. 8, a linear actuator in the form of a ratchet binder 180 has opposite ends 182 that are linearly extendable and retractable relative to one another by operating a ratchet handle 184. The opposite ends 182 of ratchet binder 180 are coupled to the respective outboard sections 158a via posts 186. Retracting ratchet binder 180 moves posts 186 and outboard sections 158a together draws upper/inboard end portions of the diagonal brace members 60 together, causing screed blade 38 to assume a flat or linear shape as shown in FIGS. 7 and 9. Further retracting ratchet binder 180 causes screed blade 38 to assume a concave-up/convex down shape (not shown). With reference to FIG. 10, extending ratchet binder 180 moves posts 186 and outboard sections 158a apart, which also urges upper/inboard end portions of the diagonal brace members 60 apart, which causes screed blade 38 to assume a concave-down shape as shown in FIG. 10. This may be useful for imparting a convex top surface to the concrete so that rainwater or other liquids will tend to run off the top surface rather than pool along the top surface.

[0035] Although screed blade 38 may be made of substantially rigid material, such as steel formed as a rectangular tube, it will be appreciated that by supporting screed blade 38 at its middle using distal pin 36, the ability to urge diagonal brace members 60 apart from and toward one another, using a linear actuator like ratchet binder 180 at middle brace member 158, will apply downward and laterally outboard pressure to outboard regions of screed blade 38 where the outboard/lower ends of diagonal brace members 60 attach, causing the screed blade 38 to flex or bow and assume a gently curved shape, so that a concave or convex or substantially planar top surface may be imparted to the concrete as desired. Optionally, any or all connection joints of brace structure 54 may be pivotable and/or detachable joints formed by bolts or pins 188 such as shown in FIG. 9 where diagonal brace members 60 couple to opposite ends of middle brace member 158, which pass freely through square openings 190 formed at upper ends of the respective upright brace members 56. The use of detachable joints formed by bolts or pins 188 would allow for brace structure 54 to be readily separated from screed blade 38, while also increasing the degree of flex of screed blade 38 in response to extension or retraction of ratchet binder 180, because less force is required to flex pinned joints than rigid joints. It is envisioned that a different linear actuator may be substituted for ratchet binder 180, such as manual or powered screw drive or a hydraulic piston/cylinder arrangement, which optionally may be controlled remotely such as from the cab of skid steer 22.

[0036] Accordingly, the concrete screed of the present invention may be used to screed and optionally compact a concrete surface at the same time, with a screed blade that is free to both pivot about a longitudinal axis and move horizontally while also being vibrated by a compacting machine as the screed blade is pulled across the concrete surface. The concrete screed is compatible for use with a frame mount that is securable to an operating machine, and further includes a frame and a pair of pins that are manually insertable and removable into mounting holes to pivotably couple the frame to the frame mount. A screed blade may be pivotably coupled to the frame via another manually insertable and removable pin, and may be telescopically adjusted to change the length of the screed blade. The frame includes a platform for supporting a compacting machine, where the compacting machine may produce vibrations that are transferred through the screed blade to the concrete in order to compact the concrete during the screeding process. A pair of straps or similar support structures are securable between the frame and the screed blade to further support the screed blade during the screeding process. The resulting concrete screed is relatively compact and readily stowable with a skid steer or other equipment, easily set up and taken apart by a single operator, and can provide both smoothing and compacting functions during use.

[0037] Changes and modifications in the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents.