LOW-MAINTENANCE, WALK-BEHIND WET/DRY CONCRETE GRINDER/POLISHER

Abstract

A walk-behind, wet/dry grinder/polisher adapted for concrete floors does not use of pulleys, belts or chains. Maintenance is significantly enhanced, as such components are typically the first to wear out and cause replacement issues. A frame with forward and rear portions pivots about a single set of right and left wheels. A planetary grinding head, powered by a propane engine, is coupled to the forward portion of the frame. In contrast to all known designs, the engine is directly, mechanically coupled to the grinding head without the use of pulleys, belts or chains. The direct, mechanical coupling to the grinding head preferably uses a centrifugal clutch. A water tank and water feed line from the water tank to the grinding head facilitate wet floor grinding and polishing. The grinding head is also encased in a shroud coupled to a tube for dust collection associated with dry floor grinding and polishing.

Claims

1. A walk-behind, wet/dry grinder/polisher adapted for concrete floors, comprising: a frame having forward and rear portions that pivots about a single set of right and left wheels; the rear portion of the frame including a handle bar assembly; an engine mounted on the frame; a planetary grinding head coupled to the forward portion of the frame and powered by the engine; and wherein the engine is directly, mechanically coupled to the grinding head without the use of pulleys, belts or chains.

2. The grinder/polisher of claim 1, wherein the engine is a propane engine.

3. The grinder/polisher of claim 1, wherein the engine is directly coupled to the grinding head through a centrifugal clutch.

4. The grinder/polisher of claim 1, further including a water tank and water feed line from the water tank to the grinding head facilitating wet floor grinding and polishing.

5. The grinder/polisher of claim 1, wherein the grinding head is encased in a shroud coupled to a tube for dust collection associated with dry floor grinding and polishing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 is a front, perspective view of a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0025] There are numerous walk-behind floor grinders and polishers, but they all use belts, pulleys or chains to couple the motor to the grinding head. This creates substantial maintenance issues, since these consumables are often the first components that need replacement, and if such replacement is required during a job and parts are not available, significant unwanted down time may be encountered.

[0026] This invention improves upon the existing art by providing a walk-behind floor grinder/polisher wherein the engine is directly, mechanically coupled to a planetary grinding head, thereby eliminating the need for belts, pulleys or chains.

[0027] FIG. 1 is a front, perspective view of a preferred embodiment of the invention, depicted generally at 100. The machine includes a frame 122 to which there is mounted an engine 114, which in this case happens to be a propane engine fed by a propane tank (not mounted). The engine includes an air intake 113 and catalytic exhaust 116 to reduce emissions.

[0028] The frame couples to a handle bar assembly 102 with right/left handles 103. The handle bar assembly 102 is hinged to the forward portion of the frame through a pivoting joint 104 with locking pins 105 enabling the handle bar assembly 102 to be adjusted and folded down for more compact transport. Various user controls are available on the handle bar assembly 102, including ignition switch 108, throttle 110, hour/tachometer 109 and emergency stop button 106,

[0029] The machine may be used for dry or wet grinding or polishing. For wet processing, water from tank 112, feeds the abrasives through water line 118. A floating shroud 120 (or rubber equivalent) covers the grinding head, and exhausts out tube 126 for dust collection if dry processing is used.

[0030] The unit pivots about right/left wheels 128, with gas springs 124 being used for weight distribution. While not visible in the photo, the engine 114 is directly coupled to the planetary grinding head through a centrifugal clutch. The clutch is between the engine and a middle gear box that acts as a speed reduce and torque increaser (2:1). Electric and manually engaged clutches may be implemented as alternatives to centrifugal. The middle gear box is bolted to the main planetary gearbox and, in turn, rotates the planetary heads. All rotational power is transmitted through shafts with keyways.

[0031] In contrast to all known designs, the engine is directly coupled to the grinding head without intervening belts, pulleys or chains. This substantially simplifies maintenance issues, since these consumables are often the first components that need replacement, and if such replacement is required during a job and parts are not available, significant unwanted down time may be encountered.