Squeegee for curved surfaces

Abstract

A T-shaped squeegee for any smooth surface, contoured or flat, comprises a thin elastic cleaning element with two parallel cleaning edges, a supporting curved and protruding rigid blade that can produce continuously varied curvature by changing the angle of attack, a handle, and holder that connect the blade and the handle. This combination of thin elastic cleaning element with channel shaped cross-section and contour matching ability of the blade provides sufficiently high contact pressure on a wide curve for removing tightly adhered dirt, efficiently.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a device for removing dirt and liquid from a smooth surface with varied curvatures, including a flat surface and more specifically to a squeegee for cleaning windshield, windows and other smooth surfaces of newer fuel-efficient, aerodynamically designed automobiles. Further, this invention is directly related to and compliments my previous invention titled CONTOUR MATCHING ICE-SCRAPER (U.S. Pat. No. 5,680,668).

2. Descriptions of the Prior Arts

Prior art squeegees are designed primarily for a flat surface, such as, a glass pane. Generally, a long elastic rubber or leather strip with a rectangular cross-section is held between two rigid, straight and parallel sheet metal strips, which are perpendicularly attached to a long handle. The soft elastic member that contacts the cleaning surface can compensate some irregularity of the surface in texture and curvature by deforming.

Many special types of squeegees are proposed and used in silk-screening on contoured surfaces. These are generally intended for a well-defined surface geometry and for limited application to that particular mass-produced article. Lately, for small articles, offset pad printers are used for printing on a contoured surface rather than silk-screening, as they are far more efficient and flexible.

A clean windshield of an automobile is essential for a safe driving. The standard-equipment windshield wipers are a pair of oscillating squeegees, which contact the glass surface securely with a help of spring loaded swing arms and holding ribs. Due to their relative importance to safe operation of vehicle in rain, enormous amounts of research and development have been done on the selection of wiper materials and the designs. One can find many issued patents on composition of wiper materials and wiper designs.

In most automobiles, a window cleaning solution and a spraying system are provided for cleaning the windshield with the wipers. This combination effectively cleans dried salt spray, dirt, frost and dust which are either water soluble or loosely adhering to the exterior surface of windshield. However, commercially available window cleaning solutions contain organic chemicals for detergency, solvency and anti-freezing. Methanol is the most common chemical used for these purposes. But when methanol evaporates into the air it forms ground level Ozone by reacting with Oxides of Nitrogen from the exhaust. If it goes into water, it becomes very toxic to living things.

Although standard-equipment windshield wipers and window cleaning solutions keep the windshield clean for safe driving, this combination cannot remove tightly adhering dirt, such as, common bird droppings. For a safer driving, we also need to clean interior surface of the windshield and windows that have widely varied curvatures, from nearly flat to concave. Obviously we need a squeegee that can apply a sufficient pressure to remove any tightly adhering debris from glass surface, both inside and out regardless of the curvature. Thus, a common flat window-cleaning squeegee needs an improvement.

SUMMARY OF THE INVENTION

This invention provides an efficient means for removing liquid or dirt from a surface with various curvatures, including a flat surface. More specifically, this invention provides more efficient squeegee for cleaning the interior and exterior surface of automotive windshield and windows. Also this invention compliments and works with my previous invention titled CONTOUR MATCHING ICE SCRAPER (U.S. Pat. No. 5,580,668) for a year round use.

Newer automotive glass surfaces range from nearly flat to a convex exterior surface with radius of curvature of about one meter. A surface with a radius of curvature shorter than a meter is difficult to cast and laminate and tends to distort driver's vision. The interior surface ranges from flat to concave surface with the corresponding negative radius. Generally, these curvatures deviate slightly from a spherical arc and differ depend on the direction.

Our comparative performance tests of various commercially available squeegees showed that an effective removal of tightly adhered dirt requires a considerable contact pressure of the wiping edge on the glass surface. Common straight-line squeegee or a wide area contacting curved squeegees with relatively soft cleaning element is too soft and flexible to generate or withstand the sufficiently high contact pressure to dislodge the dirt.

Unlike prior art squeegees, this invention consists of a thin channel shaped elastic cleaning element whose both ends are closed to form a T-shaped cavity, a rigid T-shaped blade and a handle. The cleaning element mounts on and partially covers along the top side of the blade and provides a pair of parallel cleaning edges which are easily switched by.-remounting after a half rotation or replaced with a new one as the cleaning edge wears. The handle is attached to the vertical leg of the blade to extend the reach of the cleaning element.

When the blade has a curved face with protruding top, like our contour matching ice-scraper, the two curved cleaning edges with slightly different curvatures are formed. The inner edge with shorter radius can provide various cleaning curvature by simply changing the angle of attack and thus, is used for cleaning a flat or mildly convex surfaces, such as an exterior surface of auto, and the other, for a concave surface such as an interior surface of windows or windshield.

The cleaning element is held securely by both narrow top ends of the blade, and is stretched along the both sides and covers the curved working topside of the blade. The combination of thin elastic cleaning element and the continuously variable curvature that the blade generates by varying the angle of attack provides the sufficient cleaning pressure along the wide curved line contact. Additionally, the elastic deformation of the blade overcomes slight deviations of curvature from a pure arc.

This invention is particularly useful in combination with the sharp ice-scraper blade of CONTOUR MATCHING ICE SCRAPER as this squeegee-cover acts as a sheath or a cover and prevents accidental cut. Also, this simple addition of the squeegee-cover to the ice-scraper lets year round use of the device with enhanced safety and economy.

Unlike the conventional straight-line squeegees, this invention perform better on a flat window pane by trapping water or dirt away from the both edges, or from a sash, to the central portion of the cleaning element when the handle is pulled or diverts the liquid and dirt away from the center when the handle is pushed. This lateral motion of fluid to moving squeegee distributes the fluid and improves cleaning action. The trapping of dirt and dirty water is particularly useful in cleaning interior surface of the sloping modem windshield which is hard to reach over a dash-board.

In this invention, a pinched tubular metal holder, with substantially rectangular pinched opening, holds the mounting tab, the bottom portion of the T-shaped blade, and round opening holds a long handle with a pair of bevels on the other end. The bevels prevent rotation and accidental separation of the handle. The holder can provide easy and quick but secure replacement of blade or handle. The exterior surface of the substantially rectangular pinched end also can provide a mounting column for other necessary cleaning element such as a brush or a mop.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood better by reading the following description and accompanying drawings wherein:

FIG. 1 is a perspective view of unassembled components of this invention

FIG. 2 is a detailed perspective view of the squeegee element 1 of FIG. 1

FIG. 3 is a top view of the horizontal cross-section of the squeegee cover of FIG. 2,

FIG. 4 is side view of the vertical cross-section of the cleaning element of FIG. 2, and

FIG. 5 is a perspective view of an assembled device.

BEST MODE FOR CARRYING OUT THIS INVENTION

In FIG. 1, four inter-related components of this invention are shown. They are an elastic squeegee-cover 1, a T-shaped rigid blade 2, a formed tubular metal holder 3, and a long handle 4.

The T-shaped blade 2 is one-eighth inch thick injection molded curved blade whose six-inch wide topside 20 is rounded to give two parallel arc shaped right angled edges 21 and 22 with radius of about 18 inches and whose bottom part is a rectangular mounting tab 23 with dimension of about 1.4 inch wide and three-fourth of an inch long. This blade 2 is further bent to give an arc shaped plate with radius of curvature of about 24 inches around the centerline of the T. The bending changes the arc shaped edges 21 and 22 slightly. The inner edge 21 now has a slightly shorter radius than edge 22 has. The inner edge 21 of this blade 2 has curvature of 25 inch at near zero angle of attack, to a flat surface at 45 degree and a concave surface at even larger angle of attack. For the surfaces that deviate from a pure arc, slight elastic bending of the blade 2 and deformation of the elastic cleaning element 1 can compensate for the deviation as one push the blade toward the surface. For mass production, the T-shaped blade 2 can preferably be injection molded hard and tough Polycarbonate or high impact Polystyrene. If one bevels the side 20 and makes the edge 22 from a right angle to a sharper angle, edge 21 becomes a sharp ice scraping edge that is described in detail in my related patent (U.S. Pat. No. 5,680,668). The narrow ends 24 and 25 of the blade 2 are used to stretch and hook the elastic cleaning element 1.

The holder 3 is about four inches long aluminum tubing with one inch outside diameter and 35 mil thick wall. Its one end is pinched to make a substantially rectangular opening 31 which mates tightly with the mounting tab 23 of the blade 2. The exterior surface 33 can be used to mount other component such as a mop or a brush by simply looping around the about three-fourth inch long substantially rectangular column. As a result of pinching, the holder has a pair of matching flatter slanted surfaces 34 and 35. The round opening 32 at the opposite end that mates with the handle 4.

The handle 4 is a coated hardwood with diameter slightly smaller than one inch and has varied lengths depend on the reach needed. The handle 4 has a pair of bevels 41 and 42 and a round opposite end 43 for gripping. The bevels 41 and 42 mate tightly with the inside faces of the slanted flatter parts 34 and 35 (not shown) of the holder 3. This bayonet mounting prevents rotation of the handle 1 and overcomes slight but unavoidable variation in diameter of the handle 4.

In FIG. 2, 3 and 4, a rectangular elastic squeegee element 1 has exterior dimension of a quarter inch high, three-quarter inch deep and about six inch wide. Its ends are closed to form a T-shaped cavity 13. The element 1 has a pair of about six inches long right angled working edges 11 and 12 on the opposite side of the opening of the cavity 13. Referring to the FIG. 4, the cross-section of the element 1 is a symmetrical in the both direction of width and height. The T-shaped cavity 13 is eighth inch high to match the thickness of the blade 2 and bound by rectangular wall 16 and matching pair of curved wall 14 and 15. The wall 16 is parallel with the two working edges 11 and 12 and mates with the arc shaped top side 20 of the blade 2. The inner portions of the walls 14 and 15 forms a pair of pockets and hold each narrow end 21 and 22 of the blade 2. The end 21 is inserted into the cavity 13 and engaging wall 14 first, stretching the cleaning element 1 along the blade and engaging the other end 23 with wall 15. The tension keeps the element securely on the blade 2 even when handle is pulled. The elastic element can be easily fabricated by welding both ends of about six inch long extruded rubber channel that is widely used for holding a plate glass in a high-rise buildings. For mass production, injection molding of TPE, Thermoplastic Elastomers, is better choice.

It is understood that the above description is given merely by way of illustration and not in limitation of this invention and that various modifications may be made thereto without departing from the spirit of the invention as claimed.

Claims

1. A cleaning device for a smooth contoured or flat surface comprising:

a T-shaped blade having a curved face, a mounting tab at the bottom and a wide protruding topside with a pair of narrow ends,

an elastic cleaning element having means for mounting on said blade securely and covering said topside to provide a pair of parallel protruding arc-shaped cleaning edges,

a handle, and

a connecting means between said mounting tab and said handle.

2. The cleaning device of claim 1 wherein said blade is a metal plate with uniform thickness.

3. The cleaning device of claim 1 wherein said blade is an injection molded plastics.

4. The cleaning device of claim 1 wherein said tab is a substantially rectangular and uniform in thickness.

5. The cleaning device of claim 1 wherein said element is a strip with rectangular exterior surfaces, slightly thicker than said blade and slightly shorter than the width of said topside of said blade.

6. The cleaning device of claim 1 wherein said mounting means is a T-shaped cavity in said elastic element

7. The cleaning device of claim 1 wherein said connecting means is a pinched metal tubing having a substantially rectangular opening for said mounting tab at one end and a round opening for said handle at the opposite end.

8. The cleaning device of claim 7 wherein said handle has a pair of bevels on one end that mate with a pair of slanted inside faces of said tubing.