Patent Application
20070124885
Not applicable.
The present invention relates generally to cleaning devices, and more particularly to cleaning devices that can take in liquid; devices such as wet/dry vacuums. Wet/dry vacuums include a tank that can be used to hold the liquid, and often have a mouth that can be used to pour liquid from the tank.
When filled with liquid, the tank in a wet/dry vacuum can be heavy. For large units, such as those for heavy-duty use in commercial or industrial settings, the weight can make it difficult to unload the tank.
Heavy-duty wet-dry vacuums are sometimes mounted on carts. For ease of emptying, tilt bars are sometimes provided on the cart. The tilt bar provides a support that can be used to help tilt the tank for emptying.
The use of a tilt bar can be awkward. Generally, when emptying a tank, it is desirable to position the mouth of the tank outside the base of the unit so that the liquid pours into another receptacle, rather than onto the base of unit itself. When using conventional tilt bars, the tank can sometimes flip over the tilt bar, or the cart itself can tip over. Both are usually undesirable.
The applicants have developed an improved cleaning device that may be more stable during emptying of the tank. Like prior known devices, the cleaning device has a suction unit that can be used to take in liquid, a tank that can be used to hold the liquid, a mouth that can be used to pour liquid from the tank, and wheels that form a base. It also has a pivot that can be used to rotate the tank between a normal use position and a pouring position.
In the new arrangement, the pivot is arranged so that even in the pouring position, the center of gravity of the unit remains within the horizontal range of the base. The mouth of the tank may fall outside the horizontal range of the base.
Optionally, the pivot may be located within the horizontal range of the base, in a position where it remains laterally between the center of gravity of the tank and the edge of the base when the tank is emptied. In one embodiment of this arrangement, the pivot is positioned at least 12 inches above the floor.
It is also optional to arrange the unit so that the tank is tipped toward an opening formed between opposed arms of the handle. A removable storage basket may sometimes be fitted within that opening when the tank is in the normal, use position.
The invention may be better understood by referring to the accompanying drawings, in which:
The cleaning device 10 seen in the figures can be used to take in liquid. The device includes a tank 12 that can be used to hold the liquid, a mouth 14 (
The illustrated tank 12 is a nominal 22-gallon plastic tank that is about 21 inches high and about 21 inches wide. When the tank is filled to its wet capacity and the power head 18 is removed, the liquid level is approximately 5 inches below the upper rim 22 (
The wheels 16 are part of a dolly 30. The illustrated wheels include a pair of 10-inch diameter rear wheels that are about 20 inches apart on a rear axle 32 (
The illustrated device 10 includes a pivot 40 that enables the tank 12 to rotate between a normal use position and a pouring position. In the use position (seen in
The illustrated pivot 40 is a hinge with a horizontal axis. One side of the hinge is fixed on a section of the dolly 30, and the other side of the hinge is fixed to the tank 12 or to an adapter on the tank. In the illustrations, the pivot is located within the horizontal range of the base 17, approximately 2 or 3 inches inwards from the pouring-side edge 48 of the base, approximately 15 inches above the floor (and about 12 inches above the bottom of the tank), and approximately 11 inches below the mouth 14. Although these dimensions can be varied, the illustrated distance between the pivot and the floor (given the illustrated 2- or 3-inch distance between the axis of the pivot and the inside surface of the tank) may be advantageous for pouring the tank into a standard-height toilet.
In some previously-known devices, tilt bars are positioned outside the horizontal range of the base. While these arrangements may be stable in the normal use position, tilting the tank during emptying operations generally causes the center of gravity of the unit and any contained liquid to move. If the center of gravity of the unit and any contained liquid moves rearwardly of the pouring-side edge, the unit can become unstable and tip over. Similarly, if the center of gravity of the tank itself and any contained liquid move rearwardly of the tilt bar, the tank can tip over the tilt bar.
Incoming liquid will also move the in-use center of gravity 44 of the device 10. However, arranging the device so that none of the internal volume of the tank 12 is located outside the pivot 40 or outside horizontal extent of the base 17 assures that—so long as the unit is kept level—the in-use position center of gravity will not move outside the base, no matter how much liquid is added.
More importantly, the new arrangement tends to keep the shifting center of gravity 62 (
Similarly, the illustrated arrangement keeps the center of gravity of the tank 12 itself and any contained liquid forward of the pivot 40, minimizing the risk of the tank from tipping over the pivot during emptying. This is not always necessary, however, and other arrangements can also be used.
The illustrated device 10 also has a rearwardly-extending handle 70 that has opposed arms 72 (
Optional mounts 80 (
This description of various embodiments of the invention has been provided for illustrative purposes. Revisions or modifications may be apparent to those of ordinary skill in the art without departing from the invention. The full scope of the invention is set forth in the following claims.
