GB2624654A

GB2624654A - A floor levelling device

Info

Publication number: GB2624654A
Application number: GB2217548.3A
Authority: GB
Inventors: Ekin James; Hall Martin
Original assignee: Ekin Engineering Ltd
Current assignee: Ekin Engineering Ltd
Priority date: 2022-11-24
Filing date: 2022-11-24
Publication date: 2024-05-29
Also published as: GB202217548D0

Abstract

The invention provides a secondary floor levelling device 1, suitable for the removal of high spots on an uncured or partially cured aggregate based compound forming a floor, said device comprising a first portion 2 arranged to move a second portion across the floor, the second portion comprising a head member 3 adapted to be transported across the floor for levelling of the floor, said head member 3 comprising two parallel beams 9, which oscillate in a direction extending across a direction of intended motion of the head member 3 and in a plane substantially parallel to the plane of a local region of the floor. The device 1 preferably has laser detectors 21 for detecting a laser datum plane and may provide for very efficient and accurate removal of high spots, particularly on a partially cured concrete floor. The two parallel beams 9 may each oscillate in antiphase with respect to each other.

Description

A Floor Levelling Device The present invention relates to a secondary floor levelling device suitable for removing high spots from an uncured, or partially cured, surface of an aggregate based compound such as concrete or a mixture of sand and cement.

To form a floor of concrete, for example, the concrete is first poured over the region to be floored. The concrete is then primarily levelled, or "screeded", to flatten the poured concrete into a level surface before it has cured. Once primary levelling is complete, and the concrete has partly cured, the concrete is then "floated" to bring fine aggregate and moisture to the surface, ensuring that the surface of the concrete is smooth.

Primary levelling can be performed manually, by pushing a long, straight beam over the uncured, poured concrete. However, many powered mechanical primary floor levelling devices exist and their use is more practical for larger floor areas than manually pushing a beam. These devices may comprise a main body situated outside the concrete floor region, with a head member for smoothing the concrete attached to the end of a boom arm. The boom arm is extended away from the main body, lowered such that the head member engages the surface of the concrete, and is then retracted towards to the main body. The resulting stroke of the head member over the poured concrete levels the surface and creates the primarily levelled floor. The main body then has to be repositioned for the next stroke of the head in order to ensure the entire surface area of the floor is primarily levelled.

Alternatively, a self-propelled, wheeled carriage may be used which drives through the poured concrete and drags a head member behind it, said head member primarily levelling the concrete as described above. Since the concrete is in an uncured state, the wheels of the carriage are typically partially submerged in the poured concrete.

A mechanical floor primary levelling device will often be laser guided and have laser detectors which receive light from at least one externally placed laser source. The at least one laser source defines a datum plane, which is a flat reference plane to which the floor must be made parallel and relative to which vertical distances are measured. Laser guided primary levelling devices continuously and automatically raise and lower the head member vertically to ensure that the primary levelled concrete is parallel to the datum plane.

The head members of the above devices typically comprise a plough or plough face for primarily levelling the concrete and may additionally comprise a vibrating beam that follows the plough and tamps the concrete primarily levelled by the plough. The tamping serves to at least partially float the surface. Typical primary floor levelling devices are also known in the art whose head members instead comprise augers or rollers.

For various reasons, use of primary floor levelling devices often results in high spots (those parts of the concrete floor which are locally higher than the desired floor plane) and low spots (those pads of the concrete floor which are locally lower than the desired floor plane). These can be removed by secondary levelling, such as a person manually pushing a blade on the end of a handle when the floor has partially cured, or by grinding of the cured concrete floor. The first of these processes is relatively inexpensive and can be performed as soon as the floor has partly cured, but it is not very accurate. In contrast, floor grinding is performed by a machine that can use laser guidance to obtain a high tolerance surface, but it is relatively expensive and cannot be performed until the floor has been fully cured, potentially requiring additional visits to a site and interfering with timelines of other steps in the construction process.

It is an object of the present invention to provide a secondary floor levelling device for use during or after the primary levelling of a floor formed of an aggregate based compound such as concrete, for the removal of high spots on said floor.

According to one aspect of the present invention there is provided a secondary floor levelling device suitable for the removal of high spots on an uncured or partially cured aggregate based compound forming a floor, said device comprising a first portion arranged to move a second portion across the floor, the second portion comprising a head member adapted to be transported across the floor for levelling of the floor, said head member comprising two parallel beams which each oscillate, preferably in antiphase with respect to each other, in a direction extending across a direction of intended motion of the head member and in a plane substantially parallel to the plane of a local region of the floor.

A secondary floor levelling device in accordance with the present invention is used for the removal of high spots on a floor after it has first been primarily levelled by other means, but before it has fully cured. The aggregate based compound of which the floor is formed could be a wet mix (such as concrete) or a dry mix (such as a mixture of relatively dry sand and cement). Should a dry mix be used, the dry mix would be sufficiently firm immediately after primary levelling to be operated on by a secondary floor levelling device. Should a wet mix be used, the floor would need to be partially cured before being operated on by the secondary floor levelling device.

Using a device in accordance with the present invention offers significant advantages over the known techniques discussed above.

The oscillatory sawing motion of each beam is particularly effective and efficient at removing high spots from the floor surface, especially once said floor has sufficiently hardened to support the weight of the secondary floor levelling device of the invention, but wherein the head member being mechanically powered, is still able to remove any high spots.

The two parallel beams of the device of the present invention, oscillating in antiphase, avoid any unbalanced forces acting on the first portion of the device.

This is an important feature, for the device as a whole may be supported on a partially cured wet mix aggregate based compound, and thus any oscillatory motion experienced by the first portion of the device, as would be experienced if only a single oscillating beam was employed (relying on the first portion of the device to provide a reaction force), would cause the support for the first portion, typically one or more wheels, to disturb the floor and potentially produce additional high or low spots or areas requiring further finishing.

The height of the head member relative to the first portion may be adjusted 10 within a specified range. This enables a user to set the head member at a desired position relative to the first portion to remove a desired quantity of material from a high spot.

The head member may be raised or lowered vertically relative to the first portion by means of at least one electric actuator. Electric actuators are advantageous over hydraulic actuators because they are far more responsive, however hydraulic actuators could be used as an alternative.

Advantageously, the device may further comprise at least one laser detector adapted to detect laser light from at least one externally placed laser source, the at least one externally placed laser source establishing a datum plane, with said laser detector identifying vertical displacement of the head member relative to the datum plane. Using a datum plane and identifying the vertical displacement of the head relative thereto may assist a user in adjusting the height of the head to a desired level relative to the datum plane, enabling the device to produce very accurate results and to potentially produce floors of a very high tolerance.

The device is preferably arranged to maintain the head member in a fixed vertical position relative to the at least one laser detector and to automatically adjust the height of the head member relative to the first portion in dependence on signals received from the at least one laser detector, to keep the head member at a constant height relative to the datum plane. This automates the height adjustment of the head member, reducing the possibility of human error and further increasing accuracy, as well as increasing the speed at which the floor can be secondarily levelled, by removing the need for the user to manually adjust the height of the head member.

The device may further comprise means for receiving a user input to introduce an offset to the height of the head member relative to the datum plane, from the height of the head member relative to the datum plane that would otherwise be automatically set by the device. This allows the user to pursue secondary levelling strategies such as, for example, starting with the tops of the high spots and gradually working down to the desired floor level.

The device preferably comprises two laser detectors located to either end of the head member, each of which is positioned vertically above the head member, and wherein the height of each end of the head member relative to the first portion can be adjusted independently. This keeps the head member level with respect to the datum plane, avoiding any potential discrepancies in the heights of the opposed ends of the head, which may otherwise result from any cant of the first portion of the device.

The head member may further comprise at least one vibration element to vibrate the head member vertically. This causes a tamping effect to compact, float and improve the final surface of the floor.

The head member may be arranged to move material in the direction of intended motion to fill low spots in the floor. Low spots are areas below the desired plane of the floor -the opposite of high spots. Filling them would be an advantageous additional feature of the device.

The first portion of the device may be a moveable vehicle comprising a wheeled carriage connected to the second portion and arranged to move the second portion across the floor, the second portion being arranged follow the carriage when the device is moving in the direction of intended motion.

The aggregate based compound of which the floor is formed could be a wet mix (such as concrete) or a dry mix (such as a mixture of sand and cement). In the case of a dry mix compound, the floor would be sufficiently firm to support the wheeled carriage, prior to the eventual curing of the dry mix, without disturbance of the floor surface. In the case of a wet mix compound, the floor would need to party cure to enable the wheeled carriage to be supported without disturbing the floor surface, but high spots could still be removed at this stage of curing by the oscillatory motion of the beams.

The head member following to the rear of the wheeled carriage is advantageous because it can then level any minor disturbance in the floor surface caused by the wheels moving through or over the compound. A wheeled carriage advantageously allows the device to be moved easily and quickly through or over the floor. Furthermore, a wheeled carriage may be fairly compact, and this would allow for ease of transport of the device.

Another advantage of the present invention employing two beams oscillating in antiphase is that this avoids exerting unbalanced forces on the first portion of the device. This may be particularly advantageous when the device in accordance with the present invention comprises a wheeled carriage supported on a partly cured wet mix compound floor.

The device is advantageously self-propelled. This enables the head member to push or otherwise displace larger volumes of removed material than would be possible with a hand operated machine.

As an alternative to the wheeled carriage arrangement, the first portion of the device may instead comprise a substantially horizontally extending boom arm which, at a distal end, is connected to and suspends the second portion, and wherein the boom arm can be telescopically extended or retracted to cause the second portion to move in the direction of intended motion. Employing a boom makes it possible for the first portion to be positioned outside of the floor area, avoiding any disturbance of the floor by the first portion.

The second portion of the device may comprise at least one motor and drive 10 mechanism which are arranged to create reciprocating motion of the beams. This provides an efficient, compact and cost-effective arrangement for producing oscillatory motion of the beams.

A face of at least one beam may face outwards relative to the head member, 15 and may have a series of protruding ridges, each extending from the bottom edge of the face and arranged to engage the floor. The ridges serve as teeth which would help to cut into the high spots.

The longitudinal axis of each beam may be substantially perpendicular to zo the direction of intended motion of the head member. This allows the head member to drag removed material from high spots towards low spots. Alternatively, the longitudinal axis of each beam may be angled relative to the direction of intended motion of the head member. This allows for material to be fed off one end of the head member, preventing material from accumulating on it. This would be useful if the high spots were hardened enough to be unable to fill low spots without further treatment.

According to a second aspect of the present invention there is provided a method of levelling a floor formed of an aggregate based compound, said method 30 comprising pouring aggregate based compound over the region to be floored, primarily levelling the aggregate based compound to produce the floor, waiting for

B

the aggregate based compound to partially cure, and then providing secondary levelling to at least a portion of the floor surface to remove high spots using a device as described above.

The method preferably may use concrete as the aggregate based compound A preferred embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a front perspective view of a device in accordance with the present invention, with a head member shown in a lowered position; Figure 2 is a rear perspective view of the device of Figure 1; Figure 3 is a side elevation of the device of Figures 1 and 2; Figure 4 is a plan view of the device of Figures 1 to 3; Figure 5 is a front elevation of the device of Figures 1 to 4; Figures 6a is a side elevation of the device of Figures 1 to 5, but with the head member in a raised position.

Figure 6b is a front perspective view of the device of Figure 6a; Figures 7a is a perspective view of a head member of the device of Figures 1-6b, but with the casing covering the drive mechanism removed; Figure 7b is a side elevation of the head member of Figure 7a; Figure 7c is a plan view of the head member of Figures 7a and 7b; and Figure 7d is a front elevation of the head member of Figures 7a to 7c.

Referring to Figures 1-5, a secondary floor levelling device, indicated generally as 1, in accordance with a preferred embodiment of the present invention is illustrated. The device 1 comprises a wheeled carriage, indicated generally as 2, and a head member, indicated generally as 3.

The wheeled carriage 2 is arranged to drive over a floor (not shown) formed of an aggregate based compound. It comprises a carriage 4, which is self-propelled, and wheels 5, which sit on the surface of the floor. The head member 3 is suspended off the wheeled carriage 2 by a central support 19. The wheeled carriage 2 is arranged to drive backwards (left to right as shown in Figure 3), such that the head member 3 follows behind the wheeled carriage 2.

The head member 3 comprises two beams 9, arranged to oscillate in antiphase with respect to each other. Each beam 9 comprises a plurality of ridges 10 extending from its bottom edge. As will be described in more detail below with reference to Figures 7a to 7d, each beam 9 is mounted on one side of a central mounting bar 11, which does not oscillate, and on which a drive mechanism arranged to produce the oscillatory motion of the beams 9 is located. The drive mechanism is contained within casing 12.

Mounting poles 13 are mounted at one of their respective ends to a respective end of the central mounting bar 11. To the other end of each mounting pole 13 is mounted a laser detector 21. The laser detectors 21 receive light from at least one externally placed laser source (not shown). The at least one externally placed laser source creates a datum plane, or plane of reference, and using the laser detectors 21 the vertical height of the head member 3, relative to the datum plane, can be determined.

In addition to supporting the laser detectors 21, each mounting pole 13 connects the head member 3 to the wheeled carriage 2 by slidably passing through a respective cylindrical shaft 14, extending along only part of the length of the mounting pole 13. Each cylindrical shaft 14 is fixed in position on the wheeled carriage 2 by a respective support bar 18 joined to the central support 19 of the carriage 4.

The height of the head member 3, relative to the wheeled carriage 2, can be 30 adjusted by means of a height adjustment mechanism 15. This comprises two electric actuator 16, each having a vertically extending shaft 17 connected to a respective mounting pole 13, at a point between the fixed cylindrical shaft 14 and the laser detector 21.

To adjust the height of the head member 3, relative to the wheeled carriage 2, the shafts 17 of the actuators 16 are raised or lowered by their respective actuators 16, vertically raising or lowering the mounting poles 13 slidably passing through cylindrical shafts 14 and thus raising or lowering respective ends of the head member 3.

Comparing the device 1, as shown in Figures 6a-b, with device 1, as shown in Figures 1-5, it can be seen how the head may be raised from the "working" position shown in Figures 1 to 5 to a transport position, shown in Figures 6a to 6b.

An electrical control unit 6, mounted on the wheeled carriage 3, receives and processes data from the laser detectors 21 and processes information relating to the height of the head member 3, relative to the datum plane, and provides this to the user. The electrical control unit 6 also comprises means for receiving a user input to adjust the height of the head member 3, and it is connected to each actuator 16, so that it may independently adjust the position of each end of the mounting bar 11 and thus control the height of the head member 3 in accordance with the user input and data received from the laser detectors 21. The electrical control unit 6 may further comprise means for receiving additional user inputs related to other functions of the device 1.

Indicator lights 20 are also mounted on each respective cylindrical shaft 14 These are controlled by the control unit 6 and indicate, to all around, the height of a respective end of the head member 3 relative to the height desired by the user.

The device 1 further comprises control handles 7 mounted on the carriage 4, 30 to allow the user to manoeuvre the device 1. LED lights 8 may also be operated to illuminate a region of the floor around the device 1.

With reference to Figures 7a-d, here the head member 3 is shown disconnected from the mounting poles 13 and with the casing 12 removed. The drive mechanism 31 is thus seen mounted on the mounting bar 11. Rotating flanges 32 extends from either side of the drive mechanism 31, one over each beam 9, and these are connected by respective crank arms 33 to respective beams 9.

Each beam 9 has a set of runners 34 at each end and these are arranged to fit around and slide along respective track bars 35, mounted on and parallel to the mounting bar 11. This arrangement constrains each beam 9 to move only linearly in a direction parallel to the mounting bar 11.

To produce a floor formed from an aggregate based compound, the compound is first poured over the region to be floored and a first, or primary, levelling process is then used to create a generally level floor surface. For various reasons, this process may leave high spots and possibly low spots on the surface of the floor which may not be acceptable. These are local areas of the floor which are higher or lower than the desired floor level, respectively. High spots and low spots may occur even if the primary levelling device is laser guided. To remove the high spots and low spots, secondary levelling is needed.

The secondary floor levelling device 1, in accordance with a preferred embodiment of the present invention, is arranged to perform secondary levelling on a floor formed of an aggregate based compound, once the primarily levelling has already been completed standard means in the art.

The aggregate based compound will typically be either a dry mix, such as a mixture of dry or damp sand and cement, or a wet mix, such as concrete. A dry mix floor is able to support the weight of the device 1 immediately after primarily levelling, whilst the dry mix is still in its uncured state. Secondary levelling using the device 1 could therefore be performed immediately. A wet mix floor, however, would need to be partially cured before it could support the weight of the device 1. The secondary floor levelling device 1 is therefore suitable for use on an uncured dry mix floor after primary levelling, or a wet mix floor that has had time to partially cure after primary levelling.

A floor may typically be formed from concrete and thus concrete will be referred to below, by way of example only. However, the invention is equally applicable to other aggregate based compounds.

When using the device 1, at least one externally placed laser source is placed to define a datum plane, above and parallel to the desired finished level of the floor. The laser detectors 21 on the device 1, in accordance with the present invention, receive light from the at least one laser source and the electrical control unit 6 processes this data to determine the height and cant of the head member 3 relative to the datum plane.

A user of the device 1 may typically configure the device 1, using electrical control unit 6, to cause the lower surface at each end of the head member 3 to follow the desired floor level, using the laser detectors 21 and a datum plane, to maintain the head member parallel to and uniformly spaced from the datum plane as the head member 3 travels across a region of the floor.

The wheeled carriage 2 is manoeuvred over the partially cured concrete, with the head member 3 following behind it. The head member 3, positioned at exactly the desired floor level, removes any high spots from the surface of the floor by the action of the oscillating beams 9 acting to "saw" the high spots off the bulk of the partly cured concrete, without exerting excessive force on the larger mass of concrete below the surface, which might otherwise disturb the concrete or cause the head member 3 to ride over a high spot. The protruding ridges 10 running along each beam 9 serve as teeth which helps to cut into the high spots, assisting in their removal.

The removed material may be transported by the head member 3 across the floor until it passes over a low spot, at which point the removed material falls into the low spot and fills it.

Should the user wish to pursue an alternative levelling strategy, such as, for example, starting with the tops of the highs spots and working down to the desired floor level, they may do so by using electrical control unit 6 to introduce an offset to the automatically set height of the head member 3.

A preferred embodiment of a floor levelling device in accordance with the present invention has been described above. However, it will be realised that many alternative arrangements are possible which may fall within the scope of the following claims. Particularly the head member could additionally incorporate a vibrating member to compact any disturbance in the surface of the floor, caused by the removal of a high spot, and to compact any material deposited into a low spot.

Claims

Claims 1. A secondary floor levelling device suitable for the removal of high spots on an uncured or partially cured aggregate based compound forming a floor, said device comprising a first portion arranged to move a second portion across the floor, the second portion comprising a head member adapted to be transported across the floor for levelling of the floor, said head member comprising two parallel beams which each oscillate in a direction extending across a direction of intended motion of the head member and in a plane substantially parallel to the plane of a local region of the floor.
2. A device as claimed in Claim 1, wherein the beams oscillate in antiphase with respect to each other.
3. A device as claimed in Claim 1 or Claim 2, wherein the height of the head member relative to the first portion can be adjusted within a specified range.
4. A device as claimed in Claim 3, wherein the head member is raised or lowered vertically relative to the first portion by means of at least one electric actuator.
5. A device as claimed in Claim 3 or 4, which further comprises at least one laser detector adapted to detect laser light from an at least one externally placed laser source, the at least one externally placed laser source establishing a datum plane, and said laser detector identifying vertical displacement of the head member relative to the datum plane.
6. A device as claimed in Claim 5, wherein the device is arranged to maintain the head member in a fixed vertical position relative to the at least one laser detector and to automatically adjust the height of the head member relative to the first portion in dependence on signals received from the at least one laser detector, to keep the head member at a constant height relative to the datum plane.
7. A device as claimed in Claim 6, further comprising means for receiving a user input to introduce an offset to the height of the head member relative to the datum plane, from the height of the head member relative to the datum plane that would otherwise be automatically set by the device.
8. A device as claimed in any one of Claims 5 to 7, wherein the device comprises two laser detectors located to either end of the head member, each of which is positioned vertically above the head member, and wherein the height of each end of the head member relative to the first portion can be adjusted independently.
9. A device as claimed in any preceding claim, the head member further comprising at least one vibration element to vibrate the head member vertically.
10. A device as claimed in any preceding claim, wherein the head member is arranged to move material in the direction of intended motion in order to fill low spots in the floor.
11. A device as claimed in any preceding claim, wherein the first portion is a moveable vehicle comprising a wheeled carriage connected to the second portion and arranged to move the second portion across the floor, the second portion being arranged at the rear of the carriage such that it follows the carriage from behind when the device is moving in the direction of intended motion.
12. A device as claimed in Claim 11, which is self-propelled.
13. A device as claimed in any of Claims 1 to 10, wherein the first portion comprises a substantially horizontally extending boom arm which at a distal end is connected to and suspends the second portion, and wherein the boom arm can be telescopically extended or retracted to cause the second portion to move in the direction of intended motion.
14. A device as claimed in any preceding claim, wherein the second portion 5 further comprises at least one motor and drive mechanism which are arranged to create reciprocating motion of the beams.
15. A device as claimed in any preceding claim, wherein a face of at least one beam faces outwards relative to the head member, and has a series of protruding 10 ridges, each extending from the bottom edge of the face and arranged to engage the floor.
16. A device as claimed in any proceeding claim, wherein the longitudinal axis of each beam is substantially perpendicular to the direction of intended motion of 15 the head member.
17. A device as claimed in any of Claims 1 to 15, wherein the longitudinal axis of each beam is angled relative to the direction of intended motion of the head member.
18. A method of levelling a floor formed of an aggregate based compound, said method comprising pouring aggregate based compound over the region to be floored, primarily levelling the aggregate based compound to produce the floor, waiting for the aggregate based compound to partially cure, and then providing secondary levelling to at least a portion of the floor surface to remove high spots using a device as claimed in any preceding claim.
19. A method of levelling a floor made of an aggregate based compound as claimed in Claim 18, wherein the aggregate based compound is concrete.