Blower for Floor Sander Drum

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of US provisional patent application 63/088,320 filed October 6, 2020, which is hereby incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable.

APPENDIX

Not Applicable.

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

[0001] The present invention relates to floor sanders, and more particularly to walk behind drum floor sanders.

RELATED ART

[0002] In the installation of, or renovation of, hardwood flooring, the surface of hardwood floors must be sanded. Sanding is usually carried out with a drum sander. This piece of equipment comprises a cylindrical drum, around which a strip of abrasive material is secured. A motor rotates the drum. The drum is moved around the hardwood floor surface and sands it smooth.

[0003] Floor sanders are used to refinish hardwood floors that have been covered for long periods of time with carpeting and carpet pads. Over time, the pads have deteriorated and because of compression caused by foot traffic on the carpet, adhere to the hardwood floor as a sticky, gummy material. When the floor is sanded, the adhering material heats up and softens. The heated material gums up the sandpaper, and fouls the interior of the housing, creating a difficult to clean sander and an ineffectively sanded hardwood floor.

[0004] Accordingly, there remains a need for a floor sander that can effectively remove the adhering material from hardwood floors, while also sanding the hardwood floor, which does not become fouled in the process.

[0005] The use of blowers is well known in the art of floor sanding. U.S. patents 2,069,502, 5,341,605, 5,575,510 and 7,435,160 disclose floor sanders having a blower used to move air across the motor to cool it. Often, a second blower is used to create suction from the floor inlet to the outlet dust bag to remove dust from the work environment. These two air flows merge and exit through the outlet to the dust bag. Neither of these blowers create sufficient air across the rotating drum to cool the drum and prevent the generation of heat on floor adhesives. When the adhesive is not heated by the drum sander, it can be effectively removed using a drum sander. None of the above references disclose a separate blower directed across the rotating drum.

SUMMARY OF THE INVENTION

[0006] The present invention is a floor sander comprising a drive motor, a horizontal rotating drum, a sander housing, a drum blower impeller, a vented impeller housing, and a fluid channel. The horizontal rotating drum is driven by the drive motor and has a top and a bottom. The sander housing covers the top of the rotating drum and has an inside proximate the rotating drum and an outside. The rotating drum supports and drives a sandpaper, and the bottom of the rotating drum is exposed for the sandpaper to sand a floor. The drum blower impeller is driven by the drive motor to create an air flow and is covered by the vented impeller housing. The fluid channel has a first end and a second end, and the first end is fluidly connected to the vented impeller housing. The second end is fluidly connected to the inside of the sander housing proximate the rotating drum. The fluid channel is mounted on the outside of the sander housing. The air flow is directed from the drum blower impeller through the fluid channel to proximate the rotating drum to cool the drum.

[0007] In a preferred embodiment, the drum blower impeller is a bidirectional impeller and has a drum impeller on the exterior side to create air flow to the rotating drum and has a motor impeller on the interior side to create flow across the drive motor.

[0008] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0010] Fig. 1 is a perspective view of a prior art floor sander.

[0011] Fig. 2 is a cutaway perspective drawing of a prior art floor sander with arrows indicating air flow.

[0012] Fig. 3A is a side cutaway view drawing of the drum blower of the present invention having a centrifugal drum blower impeller and a motor blower impeller.

[0013] Fig. 3B is a side cutaway view drawing of the drum blower of the present invention using a bidirectional impeller.

[0014] Fig. 4 is a side view of a drum centrifugal blower impeller.

[0015] Fig. 5A is a front view of the bidirectional impeller, showing the drum impeller.

[0016] Fig. 5B is a rear view of the bidirectional impeller, showing the motor impeller. [0017] Fig. 5 is a side view of the drum blower of the present invention mounted in a ducted housing, having a fluid channel, and mounted on a drive motor.

[0018] Fig. 6 is a perspective view of the present invention with the motor and centrifugal blower of Figs. 3 A and 5 mounted on the housing containing the sander drum. The fluid channel is mounted on the housing and the air flow is directed toward the sander drum.

[0019] Fig. 7 is a side view of floor sander of the present invention with the housing being opened, showing the sander drum, and showing the fluid channel directed toward the sander drum.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

[0021] Figs. 1 and 2 show examples of a prior art floor sander 10 having a drive motor 20, a horizontal rotating drum 30 having a top 32 and a bottom 34 driven by the drive motor and a sander housing 40 covering the top of the rotating drum, wherein the rotating drum supports and drives sandpaper 36, and the bottom 34 of the rotating drum is exposed to sand a floor. The preferred mechanism for driving the rotating drum with the drive motor is a belt 90 and pulleys.

[0022] The prior art floor sander has a motor blower impeller 24 driven by the drive motor to create an air flow directed across the drive motor for cooling. The impeller 24 is attached directly to the motor’s rotating shaft 22. The impeller is covered with a vented drive motor cover 160 to allow air intake to blow across the motor to cool it. Optionally, the floor sander has a sander outlet impeller 80 driven by the drive motor, which creates a suction air flow from the sander housing air inlet 42 to the sander housing outlet 50 which removes dust from the work environment and directs it to a collector bag 150. The sander outlet impeller 80 is attached to the drive motor by means well known in the art such as belts and pulleys or gear mechanisms. The sander housing covers the moving parts and also directs the air flow up and out to the outlet 50. There is little or no air flow directed across the rotating drum and sandpaper.

[0023] Figs. 3A and 3B are cutaway views of the drum blower of the present invention. As shown in Fig. 3A, mounted on the drive motor shaft 22 is a motor blower impeller 24 proximate the drive motor, a centrifugal drum blower impeller 100 proximate the ducted impeller housing 110, and an impeller wall 112 between the two impellers. Optionally, the impeller wall is not vented. This arrangement of impellers creates a bidirectional flow of air. The motor blower impeller 24 directs airflow to the motor 20. The centrifugal drum blower impeller 100 directs air flow to the fluid channel 120. The fluid channel 120 has a first end and a second end. The first end 121 is fluidly connected to the ducted impeller housing and the second end 122 is fluidly connected to the sander housing opening 44. The fluid channel is mounted on the exterior of the sander housing 40 and directs air flow to the rotating drum 30. The fluid channel is made from any robust material that can be formed to be an air-tight conveyer. Preferably, the fluid channel is a plastic hose made of strong, heat-resistant material, with a diameter from about one to three inches.

[0024] Fig. 3B shows a preferred embodiment of the invention, where the drum blower impeller 100, the impeller wall 112, and the motor blower impeller 24 of Fig. 3A are replaced with a bidirectional impeller 180 as shown in Figs. 5 A and 5B.

[0025] Fig. 4 is an example of the preferred centrifugal blower impeller 100 which creates sufficient air flow to effectively cool the rotating drum. The centrifugal impeller, when rotated, moves air in a direction at an angle to the incoming air. It has a ducted impeller housing to direct the outgoing air in a specific direction.

[0026] Fig. 5 shows the centrifugal drum blower impeller 100 in a ducted impeller housing 110 mounted on the drive motor 20. The vented drive motor cover 160 from Fig. 1 has been removed from the drive motor before the centrifugal impeller 100 and the impeller wall 112 are mounted on the drive motor drive shaft in front of the motor blower impeller 24. The ducted impeller housing 110 is mounted over the centrifugal impeller 100 and is fluidly connected to fluid channel 120. The fluid channel 120 directs the flow of air onto the rotating drum.

[0027] As shown in Figs. 3B, 5A and 5B, in a preferred embodiment, the drum blower impeller is a bidirectional impeller 180 and has a drum impeller on the exterior side 181 to create air flow to the rotating drum and has a motor impeller 182 on the interior side to create flow across the drive motor. Preferably, the bidirectional impeller 180 is an approximately flat circular disc having two sides. The sides have fins radiating from the center to the circumference edge of the disc. Preferably, the fins on each side are different, with the larger fins on one side being used to drive the air to the rotating drum, and the smaller fins on the other side driving the air to the drive motor. In the center of the bidirectional motor is an opening suitable to mount the impeller on the drive motor shaft 22.

[0028] Fig. 6 shows the floor sander with the centrifugal impeller in the ducted housing from Figs. 3A and 5. The centrifugal impeller is drivingly mounted on the drive motor to rotate the centrifugal impeller, and the drive motor drivingly mounted proximate the drum housing to drive rotating drum. The channel 120 is mounted on the exterior of the sander housing. It is fluidly connected from the ducted housing through the drum housing to direct the air flow from the ducted housing to the rotating drum to provide cooling.

[0029] Fig. 7 shows the floor sander with the sander housing open to show the fluid channel second end 122 through the housing at sander housing opening 44 proximate the drum. The fluid channel 120 provides air flow over the drum to cool the drum.

[0030] Further contemplated in this invention is sander modifier kit which includes, at least in part, a ducted impeller housing, a bidirectional impeller, a fluid channel having a first and a second end, and miscellaneous connecting parts such as couplers, screws, bolts, etc. suitable for attaching the included parts to a drum floor sander.

[0031] The embodiments were chosen and described to best explain the principles of the invention and its practical application to persons who are skilled in the art. As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.