Patent Application
20200108482
None
None
This invention related generally to equipment for finishing concrete floors and other slabs and more particularly to an attachment for use with a floor treating machine for finishing hardened concrete by grinding and ultimately polishing it.
Others have disclosed the ability to convert a power trowel to a concrete finishing machine. The LAMPLEY U.S. Pat. No. 7,481,602 discloses such an invention. In the drawings and specification thereof there is described a circular pan. On the upper major surface thereof are brackets for affixing the pan to the blades or arms of a power trowel. Affixed to the lower side of the circular pan are radial or linear bearings, schematically represented in
As is further explained in the LAMPLEY '602 patent, an intermediate layer 28 is disposed between the backing plates 24 and rotating attachments 40. The intermediate layer is disclosed as being a spongey plastic or rubber material the purpose of which is to allow the diamond bearing backing plates to deform into and ride over irregularities in the concrete surface being finished once the concrete has been allowed to harden.
The present invention is deemed to be a significant improvement over the LAMPLEY device in that it provides a superior method of controlling the way in which diamond abrasives are allowed to interact with the concrete surface being finished. Rather than relying upon a sponge rubber layer to provide some limited flexibility to the backing plates as in the LAMPLEY '602 patent, we have devised a bearing mounting arrangement for the abrasive backing plates that selectively can be made to angulate about a vertical axis as irregularities in the floor surface are encountered or the shaft can be locked so as to be only able to spin about a vertical axis. In this way, the floor can initially be treated with the backing plates free to angulate so as to eliminate bumps and depressions in the concrete, followed by operation in the lock mode to polish the surface once the irregularities have been eliminated.
The present invention comprises a device for coupling abrasive drive plates to the rotatable arms of a floor grinding/polishing machine. A sheet metal driver with a polygonal shape in its plan view has an upper major surface and a lower major surface. Affixed to the upper major surface are channels for joining the driver to the arms or blades of the floor treating machine. Also mounted on the upper major surface of the driver is at least one bearing housing containing a spherical bearing for journaling a shaft to which is attached a backing plate having an abrasive on its bottom surface. The spherical bearing allows the shaft and backing plate to spin about a longitudinal axis of the shaft and for that longitudinal axis the shaft to angulate or swing through an arc as the power trowel with the device of the present invention affixed is swept over the concrete floor surface being treated.
Further included is a locking cap containing a ball bearing which when bolted to the top of the bearing housing constrains the shaft to rotation solely about a vertical axis.
The foregoing features, objects, and advantages of the invention will become apparent to those skilled in the art from the following detailed description of a preferred embodiment, especially when considered in conjunction with the accompanying drawings in which like numerals in the several views refer to corresponding parts.
This invention is being described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use embodiments of the example as required. However, it is to be understood that the invention can be carried out by specifically different devices and that various modifications can be accomplished without departing from the scope of the invention itself.
This description of the preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of the invention. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top”, “bottom”, and derivatives thereof (e.g. “horizontally”, “downwardly”, “upwardly”, etc.) should be construed to refer to the orientation as then described or shown in the drawings under discretion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “connected”, “connecting”, “attached”, “attaching”, “join”, and “joining” are used interchangeably to refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressly described otherwise.
In accordance with one preferred embodiment, a device for attaching rotatable, abrasive carrying drive plates to the rotatable motor drive arms of a floor treating machine is indicated generally by numeral 10 and is seen to comprise a polygonal shaped driver 12, here shown as a rectangle or square having rounded corners as at 14. The polygonal driver 12 has an upper major surface 16, a lower major surface 18, and corner walls 20 projecting upward from the surface 16 of the driver 12. The walls serve to ease removal of the assembly from beneath the machine (not shown) to which the assembly may be attached. The side walls further serve to distribute water flowed during polishing operations from the driver 12 onto the floor.
Welded or otherwise attached to the upper major surface 16 is a plurality of U-shaped channels 22, preferably of steel, allowing them to be snapped onto the arms of a motor driven floor treating machine.
With continued reference to
As seen in
Fitted onto the lower end 42 of the shaft 30 is a quick connect member 40. The quick connect member 40 has a central bore 42 shaped to fit about the lower end portion 42 of the shaft 30 and is preferably secured thereto by means of a set screw 44. The quick connect device 40 includes a conventional spring ball detent 47 inserted into a transversely extending bore 46 that serves to retain a drive plate 48 (
As is best seen in
Referring now to
Those skilled in the art can appreciate that by employing a spherical bearing, as at 29, in the bearing housing 24, the drive plates 48 carrying the abrasives 50 are able to tilt in all directions about a central, vertical axis and this has been found to be extremely effective in smoothing out irregularities in the concrete surface being treated.
In some uses of the present invention, it may be desired to constrain the tilting action afforded by the spherical bearing so that the drive plates remain parallel to the surface of the concrete being addressed. To achieve this result, there is provided a locking mechanism, identified in
This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices.
