WO2005042848A1

WO2005042848A1 - A levelling device

Info

Publication number: WO2005042848A1
Application number: PCT/AU2004/001491
Authority: WO
Inventors: Percy Linton Smith
Original assignee: Percy Linton Smith
Priority date: 2003-10-28
Filing date: 2004-10-28
Publication date: 2005-05-12
Also published as: AU2003257890A1; AU2003257890B2

Abstract

A levelling device (1) is disclosed (1) that includes a levelling bar (2) supported by a mainframe (3), and a pair of wheeled side carriages (4) which are able to be manoeuvred to avoid obstructions and for height adjustment relative to the mainframe allowing adjustment for different tracking surfaces. Also disclosed is a levelling device having a platform for mounting a vibrating device, the platform being pivotally attached to the trailing end of the mainframe and adjustable from a horizontal plane to a substantially vertical plane behind the levelling bar.

Description

A LEVELLING DEVICE Field of Invention This invention relates to levelling devices of the type used to level discrete materials such as topsoil, bark, graded stone, freshly laid concrete and the like.

Background A fundamental form of levelling device is a simple screed bar used to level materials with respect to supports in the form of previously laid materials and or formworks. Concrete paths and driveways are traditionally formed in this manner. The laying of concrete is a staged process where mixed wet concrete is initially laid, roughly levelled prior to screeding, and then after a period of time, floated and finished. Vibrating freshly laid concrete allows the finishing process to be sped up. Accurate levelling also allows finishing to be sped up. Whilst there are numerous types of machines which have been developed in the past to improve the efficiencies of laying concrete, all such devices are fundamentally screeding devices and the contribution of machinery is merely to reduce physical effort not necessarily speeding up the concrete laying process. It is an object of the present invention to provide a simple and effective levelling device which can be operated manually on large or small scale projects to generally improve efficiencies. Further objects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

Disclosure of Invention According to the present invention, there is provided a levelling device comprising (a) a levelling bar secured to a mainframe, (b) a pair of wheeled side carriages pivotably connected to each side of the mainframe in a manner which allows the side carriages to track on support surfaces to either side of a body of loose material to be levelled and when required to pivot on the pivot axis to avoid obstructions and/or to facilitate the levelling of materials having a curved or irregularly shaped edge. The side carriages are slidable on a horizontal plane with respect to the mainframe to increase or reduce the spacing between the side carriages and adjacent ends of the levelling bar. Each side carriage is height adjustable relative to the mainframe. Each side carriage comprises a subframe having parallel top and bottom rails, a wheel or castor chassis member, two parallel uprights extending through the top and bottom rails from the chassis member and biasing means associated with the subframe which resists displacement of the chassis member with respect to the subframe. The top and bottom rails of the subframe are slidable on the parallel uprights. The trailing end of the mainframe which is adjustable between a horizontal plane and a substantially vertical plane behind the levelling bar. The platform mounts a vibrating apparatus. The side carriages can be adapted to be detached from the mainframe. The device may have a number of attachments attached thereto.

Preferably, the attachments are removably attached to the device. One attachment may comprise a broom carrier. The broom carrier may have a frame that is pivotally connected to the device. The frame may be movable between an operative position in which the frame is generally parallel to a surface being worked and a non-operative position in which the frame is located away from the surface. The frame may be engageable with brackets carried on a broom to enable the broom to slide across the frame. The broom may be set at a desired height relative to the broom carrier. Another attachment may comprise a vibrator for vibrating reinforcement in the concrete. The vibrator may include a frame for attachment to the device. The frame is suitably removably attached to the device. The frame carries at least one downwardly extending member. The frame is suitably pivotally connected to the levelling device. The at least one downwardly extending member extends into freshly poured concrete to a depth sufficient for the member to contact reinforcement in the concrete. When the member contacts a reinforcing bar, it imports vibration to the reinforcing bar to thereby assist in settling of concrete around the reinforcing bar. In use, as the device is moved forwardly over the concrete, the at least one downwardly extending member contacts a reinforcing bar. As the device is moved forwardly, the frame pivots upwardly and the at least one downwardly extending member rides up over the reinforcing bar. The downwardly extending member then drops down again into the concrete until it contacts a further reinforcing bar. The device may also be provided with a cutting attachment for cutting the concrete, for example to cut slots in the concrete to allow for expansion. The cutting attachment is most suitably attached to the broom carrier. The cutting attachment may comprise a lower frame positionable under the broom carrier frame, an upper frame positionable above the broom carrier frame and connection means for connecting the lower and upper frames together. The cutting attachment further includes a cutting blade for cutting a groove or slot into the concrete, h use, the lower and upper frames are positioned and connected to each other such that they can move over the broom carrier. The cutting attachment frame is then moved relative to the broom carrier frame so that the cutting blade forms the groove or slot in the concrete.

Brief Description of the Drawings Aspects of the present invention will now be described with reference to the accompanying drawings in which: Figures 1 to 3 are side views of a levelling device according to the present invention; Figure 4 is a front perspective view of the levelling device of Figures 1 to 3; Figure 5 is a front perspective view of the levelling device of the present invention in a dis-assembled state; Figure 6 is a rear view of the levelling device of the present invention; Figure 7 is a plan view of an upper frame part of a concrete cutting attachment for use with the present invention; Figure 8 is a plan view of a lower frame part of a concrete cutting attachment for use with the present invention; Figure 9 is a side view showing detail of how the upper frame part of

Figure 7 and the lower frame part of Figure 8 are connected; Figure 10 is a side view showing detail of how the upper frame part of Figure 7 and the lower frame part of Figure 8 connect around the broom carrier frame; Figure 11 shows detail of the connection of the blade assembly to the lower frame part; Figure 12 shows a plan view of a vibrator attachment for use with the present invention; Figure 13 shows a front perspective view of the vibrator assembly of Figure 12; Figure 14 shows a side perspective view of the vibrator apparatus of

Figure; Figure 15 shows a front perspective view of the vibrator assembly of Figure 12 with one of the probe carriers removed to show how the probe carriers fit into the channel sections; and Figure 16 shows a similar view to Figure 14 but from the other end and showing the probes riding up over reinforcement bars. With respect to the drawings, the present invention provides a levelling device generally indicated by arrow 1 comprising a levelling bar 2 secured to a mainframe generally indicated by arrow 3 and a pair of wheeled side carriages generally indicated by arrow 4 pivotably connected to each side of the mainframe 3 in a manner which allows the side carriages to track on support surfaces to either side of a body of loose material to avoid obstructions and/or to facilitate the levelling of materials having a curved or irregular border. The front face (2a) of the levelling bar 2 is curved so that materials coming into contact with the bar will roll as the device moves forward and consequently provide less resistance. The side carriages each comprise a subframe 5 having parallel top and bottom rails 6 and 7, a wheel or chassis rail 8 and two parallel μprights 9 which extend through the top and bottom rails. The uprights 9 have lower ends fixed to the chassis rails 8 and upper ends which extend substantially above the top rails 6 of the subframe. The uprights 9 are slidable with respect to the top and bottom rails 6, 7 and compression springs 10 are fitted between the top rails and a lockable collar 11. The upper ends of the uprights 9 are joined by a connecting member 12. As best exemplified by Figure 6, each of the side carriages 4 are connected to the mainframe 3 via pivot arrangements generally indicated by arrow 13 including plates 14 having wheel sets 15 which engage in tracks 16 fixed to the mainframe, thus, the side frames are able to move in opposed directions depending on the task at hand. The pivot arrangements 13 enable the side carriages to be pivoted through an arc of approximately 270 degrees. The mainframe 3 has two side plates 17 with respect to which pivotal connection to a broom carrier generally indicated by arrow 18 and a roller 19 is made. The links 20 provide pivotal support via pivot pins 21 the roller 19 from one end and are rigidly connected directly to the broom carrier 18 at the other end, in an arrangement which allows the broom carrier 18 to be moved into a first non-operative position (Figure 1), a second position (Figure 2) in which the roller 19 is adjacent the levelling bar 2 and to a third position (Figure 3) where the roller is not in use and the broom carrier 18 is in a an operative position. The roller can be locked in the operative position of Figure 3 by locking pins (not shown). The carrier 18 is hinged to the front face 22 of the levelling bar and when lowered into an operative position (Figure 3) is stabilised by flexible stays 23. The broom carrier frame 18 has parallel rails 24 (see Figures 4 and 5) which enable a broom 25 to be set at the desired height and manouvred across a newly laid surface. Brackets 26 attached to the broom slide on upper surface at the rails during sweeping. The pivot arrangement 13 allows the mainframe 3 to be released from the side carriages 4 (see Figure 5). Should this be necessary for transportation and storage. The device at the present invention provides for levelling, smoothing and sweeping operations to be carried out on laid concrete and other discrete materials. A vibrating device (not shown) can be mounted on the top of the levelling bar and secured by a quick release pin. The device at the present invention is simple to operate, it needs only two adjustments for multiple operations and no tools are required except when lengthening or shortening beams. Use of the device is a two-man operation with forward and other motions being by operators to either side of the device. Each operator manipulates the side carriage and mainframe adjacent their side of the device. To operate the device an operator adjusts the height of the levelling bar

2 to approximately fifty millimetres above the form work, then presses down on the mainframe 3 to make contact with the material being levelled. As the device is moved forward the excess material will build up in front of the levelling bar. If too much is building up the downward pressure on the mainframe can be released to skim the surface at a higher level. To stop the excess material being lost over the edges of a formwork one side carriage can be moved forward while holding the other stationary. This procedure will move the bar diagonally across the surface below pushing the material in to the formed area, and when repeated on the other side, a triangular section will now be left in the centre. Both carriages can then be made parallel and moved forward. The levelling bar 2 can also be used as a trowel by moving the carriages backwards and forwards. If an area widens or narrows the carriages will slide on the mainframe to the desired width. The mainframe can also turn a full circle. The side carriages 4 and levelling bar 2 can be operated in several positions, with both carriages running on top of a formwork, both carriages running on a ground surface outside the formwork and up to 200mm below the top of the formwork, one carriage on the ground outside the formwork and one on top of the formwork, both carriages on top of the formwork with the levelling bar lowered up to 200mm on one or both sides on the inside of the formwork, in this later situation the carriage frames will be locked on to the rods at the required height and not suspended on the springs. A vibrating device can be mounted on top of the levelling bar, it will assist in bringing the fine particles and moisture to the surface when levelling concrete. Where a site upon which materials are to be laid is sloping the mainframe may be constructed in two parts with the parts being raked to suit a particular terrain. Raking may be achieved by having angled adjoining ends of each part of the mainframe or the use of wedges between the adjoining ends to achieve the desired slope. Sweeping of a surface is possible by using the broom carrier. When suspended above a formwork at the same height as the levelling bar, an operator presses down on the beam to meet the top of the formwork and pushes the broom along the carrier moving forwards or backwards. When releasing downward pressure on the mainframe, it will rise above the formwork and the process can be repeated as required. The roller 19 can be positioned under the mainframe, by removing a pin at each end, positioning the roller in a fixed position and relocating the pins through the side plate 5. With the roller in the lowered position it is now below the levelling bar and ready for use. The present invention provides a relatively low cost levelling device which can be used for speedily levelling and finishing concrete or other discrete materials. Figures 7 to 11 show various views of a concrete cutting attachment for use with the levelling device of the present invention. The concrete cutting attachment shown in Figures 7 to 11 is particularly useful for cutting or forming grooves or slots into poured concrete. This encourages the concrete to crack along the grooves or slots as it sets, which provides a neater finish. The concrete cutting attachment comprises an upper frame, as shown in

Figure 7 and generally referred to by reference numeral 30 and a lower frame 31, as shown in Figure 8 and generally referred to by reference numeral 31. Figures 7 and 8 also show the transverse rails 24 of the broom carrier attached to the levelling device and as shown in Figures 1 to 6. The upper frame 30 includes frame members 32 and 33 that extend transversely to rails 24. The upper frame 30 also includes frame members 34, 35 that extend generally parallel to rails 24. A cross member 36 is fixed between frame members 34 and 35. Cross member 36 carries a broom and receptacle 37 for receiving the end of a broom handle. This is used to facilitate movement of the upper frame 30, as will be explained hereunder. Frame member 32 has wheels or rollers 38, 39 mounted at opposite ends thereof. Similarly, frame member 33 has wheels or rollers 40, 41 mounted at opposite ends thereof. As can be seen from Figures 7 and 10, the wheels or rollers 38, 39, 40, 41 include downwardly depending shoulders 42 that extend down past the sides of rails 24. Frame members 32 and 33 are also provided with apertures 43, 44, 45 and 46. The lower frame 31 shown in Figure 8 comprises frame members 47 and 48 that extend transversely to rails 24. The lower frame 31 also includes frame members 49, 50 that extend generally parallel to the rails 24. The frame members 49, 50 are joined to the frame members 47, 48, for example by welding or appropriate bolts. A blade assembly 51 is attached by appropriate nuts and bolts 52, 53, 54, 55 to respective frame members 47, 48. The details of attachment of the blade assembly to the frame members 47, 48 will be explained in more detail with reference to Figure 11. The lower frame also includes upstanding bolts 54, 55, 56, 57. Bolts 54, 55, 56, 57 are positioned such that they come into register with respective holes 46, 45, 44, 43 of the upper frame 30. Frame member 47 has wheels or rollers 58, 59 attached at opposite ends thereof. Similarly, frame member 48 has wheels or rollers 60, 61 attached at opposite ends thereof. As best shown in Figure 10, the wheels or rollers fit in the space defined between the respective downwardly depending shoulders 42 of the associated bracket on the upper frame. In order to mount the cutting apparatus to the broom carrier, the lower frame 31 is positioned under the broom carrier with the wheels or rollers 58, 59, 60, 61 being placed in alignment with respective rails 24. The upper frame 30 is positioned such that the wheels or rollers 38, 39, 40, 41 are placed into register with respective rails 24 and such that the bolts 54, 55, 56, 57 extend through the respective holes 46, 45, 44, 43. Wing nuts or other nuts can then be used to bolt the upper frame to the lower frame. A suitable assembly is shown in Figure 9. As can be seen from Figure 9, bolts 56 and 57 are each provided with nuts 62, 63. Nuts 62, 63 are threadably engaged with respective threads 64, 65 on the bolts 56, 57. Similarly, wing nuts 66, 67 are then threadably engaged with the bolts 56, 57 to bolt the upper frame and the lower frame together. If it is desired to change the spacing between the upper frame and the lower frame, the position of nut 62, 63 is adjusted by screwing those nuts in the appropriate direction. As best shown in Figure 10, the upper frame and lower frame are joined together such that the rail members 24 are positioned between the wheels or rollers 38 and the wheels or rollers 58. Suitably, the upper frame and lower frame are bolted together such that they can be moved along the rails 24 of the broom carrier frame. The concrete cutting attachment also includes a blade assembly 51, that is best shown in cross-section in Figure 11. Blade assembly 51 includes a blade carrying member 68 having a lower most region 69 that carries a downwardly extending blade 70 as shown in Figure 8, blade 70 extends substantially along the length of the blade carrying assembly 68. The blade assembly 51 is connected to respective frame members 47, 48 using a connection arrangement as shown in Figure 11. In Figure 11, bolts 52, 53 extend through appropriately formed apertures in blade carrying member 68. The bolts 52, 53 also extend through appropriate holes in frame member 48. Bolt 52 is provided with a nut 71 that is threadably engaged with the thread of bolt 52. Similarly, nut 72 is threadably engaged onto the thread of bolt 53. Further nuts 73, 74 are used to retain the bolts 52, 53 on the frame member 48. A similar arrangement is used to connect the other end of blade assembly 51 to frame member 47. The arrangement shown in Figure 11 allows the depth and the angle of the blade to be adjusted as required. hi order to use the concrete cutting attachment shown in Figures 7 to 11, the upper and lower member frames are bolted together such that they can move along rails 24. When it is desired to form a groove or slot in the concrete, the levelling device is stopped, the broom carrier is pivoted downwardly to the operative position, which also causes the concrete cutting attachment to be moved to an operative position. The blade 70 extends into the concrete. A broom handle is inserted into receptacle 37 and an operator pushes on the broom handle to cause the concrete cutting attachment to move along the rails 24 of the broom carrier frame. This movement causes the blade 70 to move through the concrete to thereby form the groove or slot. The blade 70 may suitably be approximately 1mm in width to form a neat groove or slot. Figures 12 to 16 show various views of a vibrator attachment for use with the apparatus of the present invention. The vibrator attachment is removably attached to the apparatus in a similar fashion to the manner of attaching the broom carrier shown in Figures 1 to 5. hi particular, the vibrator attachment 80 has projecting lugs 81, 82, each of which carry pins 83, 84. Pins 83, 84 can be connected to the distal ends of links 20 shown in Figures 1 to 5. Thus, the vibrator attachment 80 can be pivotally attached to the levelling device. For clarity, the levelling device has been omitted from Figures 12 to 16. The vibrator attachment 80 comprises a frame 84 made by welding together two channel sections 85, 86. Each channel section comprises a C-shaped section having open ends at both ends. Each channel section has lower walls defined by flanges 87, 88, 89, 90. Each channel section can receive a probe carrier, such as that shown at reference numeral 91 in Figure 15. Each probe carrier has a probe frame 92 having two probes 93, 94, in the form of respective downwardly extending members, mounted to a floor of the probe carrier. The probe carrier 91 is sized to slide into the channel sections 85, 86 and to be slidably movable along the channel sections to allow the probe carriers to be positioned at a desired position within its channel section. Figure 12 shows two probe carriers 91a and 91b having respective probes 93 a, 94 a and 93b, 94b. By virtue of the size of the probe frames and the channel sections, the probe frames cannot twist or rotate to any great degree once placed in the channel sections. As also shown by comparing Figures 12 and 15, the lateral position of the probe carriers in their respective channels can be selectively varied to accommodate different width concrete pours, with Figure 12 showing an arrangement suitable for a wide pour and Figure 15 showing an arrangement suitable for a narrower pour. i use, the probes 93a, 94a, 93b, 94b extend into wet concrete to a depth sufficient to contact reinforcement laid in the wet concrete. When the probes contact the reinforcement bars, the vibrator attached to the levelling apparatus transfers vibrations through to the reinforcement bars, which assists in settling the concrete around the reinforcement bars. During use of the vibrator attachment shown in Figures 12 to 16, the levelling apparatus is moved in a forward direction (which is to the left in Figure 16). The probes will contact reinforcing bars 103, 104 (see Figure 16). As the levelling apparatus is moved forwardly, contact between the probes and the reinforcing bars will cause the frame 80 to rotate upwardly about the pivotal connection of the frame to the levelling device (as shown in Figure 16). This causes the probes to ride up and over the reinforcing bars 103, 104. Once the probes have moved out of contact with the reinforcing bars, the weight of the vibrator attachment causes the probes to again drop down through the concrete and adopt the position essentially as shown in Figure 14. The probe carriers 91a, 91b may be moved to any convenient position along their respective channels. For example, if a narrow strip of concrete was to be treated, the box members 91a and 91b could both be moved to a central part of the frame. The probes carried in channel 85 are offset to the probes carried in channel 86 by a distance that is preferably equal to the distance between adjacent reinforcing bars in a reinforcing mesh. The probes preferably extend approximately 30mm below the reinforcing mesh. As ahown in Figure 16, the probes 93a, 93b may have a curved lower end. This is useful if additional vibrating of the reinforcing mesh is required. In this event, the vibrator attachment can be moved backwards once it has passed over the reinforcing bars so that the probes can again be brought into contact with the reinforcing bars that have just been contacted. The curve in the lower end of the probes assist sin imparting vibration to the reinforcement. Aspects of the present invention have been described by way of example only and modifications and conditions may be made without departing from the scope of the invention as defined in the appended claims.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1. A levelling device comprising (a) a levelling bar secured to a mainframe, (b) a pair of wheeled side carriages pivotably connected to each side of the mainframe in a manner which allows the side carriages to track on support surfaces to either side of a body of loose material to be levelled and when required to pivot on the pivot axis to avoid obstructions and/or to facilitate the levelling of materials having a curved or irregularly shaped edge.

2. A levelling device as claimed in claim 1 wherein the side carriages are slidable on a horizontal plane with respect to the mainframe to increase or reduce the spacing between the side carriages and adjacent ends of the levelling bar.

3. A levelling device according to claim 1 or claim 2 wherein each side carriage is height adjustable relative to the mainframe.

4. A levelling, device as claimed in claim 3 wherein each side carriage comprises a subframe having parallel top and bottom rails, a wheel or castor chassis member, two parallel uprights extending through the top and bottom rails from the chassis member and biasing means associated with the subframe which resists displacement of the chassis member with respect to the subframe.

5. A levelling device as claimed in claim 4 wherein the top and bottom rails of the subframe are slidable on the parallel uprights.

6. A levelling device having a platform pivotably attached to the trailing end of the mainframe which is adjustable between a horizontal plane and a substantially vertical plane behind the levelling bar.

7. A levelling device as claimed in claim 6 wherein the platform mounts a vibrating apparatus.

8. A levelling device as claimed in claim 7 wherein the side carriages are adapted to be detached from the mainframe.

9. A levelling apparatus as claimed in any one of the preceding claims further comprising a broom carrier releasably attached thereto, the broom carrier including a frame being movable between an operative position in which the frame is generally parallel to a surface being worked and a non-operative position in which the frame is located away from the surface, the frame being adapted to guide a broom in transverse movement relative to a direction of travel of the levelling device.

10. A levelling apparatus as claimed in claim 9 wherein the frame includes at least two spaced transverse rails that engage with brackets on a broom to enable the broom to slide across the rails.

11. A levelling device as claimed in claim 9 or claim 10 further comprising a cutting attachment having a lower frame for positioning under the broom carrier frame, an upper frame for positioning above the broom carrier frame and a connecting means for connecting the lower frame to the upper frame such that the carrier attachment can move relative to the broom carrier frame, the cutting attachment further having a cutting blade for forming a groove or a slot in the concrete.

12. A levelling device as claimed in any one of claims 1 to 8 further comprising a vibrator attachment for vibrating reinforcement in the concrete, the vibrator attachment having a frame for attachment to the device, the frame carrying at least one downwardly extending member, the at least one downwardly extending member extending into freshly poured concrete to a depth sufficient for the member to contact reinforcement in the concrete, said downwardly extending member being movable such that it rides up and over the reinforcement as the device moves forwardly over the concrete.

13. Apparatus as claimed in claim 12 wherein the at least one downwardly extending member is mounted to a carrier element, the carrier element being slidably received within at least one channel section in the vibrator attachment frame.