SURFACE ABRADING MACHINE
An apparatus for abrading surfaces has a first manifold mounted proximate one end of a shaft, and a second manifold mounted distal to one end of the shaft, said first and second manifolds being constructed to receive and distribute a fluid under positive pressure and vacuum pressure, the shaft being connected to the first and second manifolds to support the manifolds and the shaft includes fluid pathways to conduct air and vacuum flows of the fluid between the manifolds, and an end effector for treating surfaces.
This invention related to the art of machines used for abrading surfaces, particularly such machines that can be operated by a standing operator.
BACKGROUNDMachines used for abrading surfaces are known. Such machines typically comprise a rotational abrading unit attached to a grip or a handle for allowing an operator to control the machine while it moves across a surface to be treated. Such machines may produce objectionable vibrations, require high grip forces, or impose poor operational postures that limit the length of time an operator can operate the machine without injury.
Generally speaking, the more powerful the tool, the more vibration it generates, and tools above a certain horsepower are considered to be too heavy or to vibrate too much for an operator to control holding with only one hand and, therefore, are equipped with grip configurations suitable for two hands. Tools that require two-handed operation, therefore, may produce so much vibration that neither of the operator's hands can release a firm grip on the tool while it is powered, so as to, for instance, operate a control switch or dial.
Not all surfaces to be abraded have of a suitable height to be easily treated by operator in a standing position, and even those surfaces that are accessible might be so large that the operator must lean forward and reach out in an ergonomically unsuitable manner. While there are health risks associated with every sanding operation, it is especially difficult to operate hand tools to abrade horizontal surfaces that are at a floor level, such as the upper surfaces of aircraft wings or a ship's decks. Existing extension shafts purporting to allow abrading tools to be operated at a distance from the operator's hands by one standing comfortably often do not allow the operator to control the tool well and can also cause loss of air supply or impose hose-routing issues, which reduce productivity and complicate operation. Such extension shafts, which must be rigid to allow the operator's control actions to extend to the tool, will necessarily conduct vibrations of the tool to the operator, who must therefore grip the extension shaft tightly to control the vibration. This increased grip not only causes fatigue and can lead to vibration injuries, but also makes it more difficult to operate any control switches or dials which might be on the extension shaft, as letting go with a hand so as to operate any control switch or dial makes it more likely the operator will lose control of the tool, risking damage to the surface being abraded, injury to the operator, or potentially dropping the tool itself, which in certain industrial environments can be catastrophic.
Further, simplification of the operation of machines of this type will reduce operator fatigue.
SUMMARY OF THE INVENTIONIn accordance with the invention, a fully pneumatic, standup abrading surface treatment machine is provided that can use surface sanding, grinding and polishing tools, absorbs vibration, and is operable in a comfortable, standing posture. A Human-Machine Interface (HMI) design provides natural hand/arm orientations for long term usage, by the use of comfortable geometry (size, shape, & angle), stress-free operations for back, knees and hand/wrists, ergonomic solutions allowing stress-free and comfortable operation by the operator that improves operator posture eliminating the need for the operator to use an ergonomically compromised posture such as kneeling or leaning forward, reducing the operator's required grip force, and reducing vibration transmitted to the operator.
The design of the invention includes interchangeable end-effectors to allow different abrading operations to be performed as well as increased longevity of tool and associated hardware. The range of angles of the handle allows increased maneuverability, and a motion stop engages transitional motion to supersede rotational motion. The design also prevents the unintentional winding of fluid lines.
A lifting handle is padded similar to that of the handlebars and is conveniently placed at or near the center-of-gravity for balanced transportation, and the lifting handle is also configured to carry fluid from the manifolds to external fluid lines.
The invention provides a cartridge valve on the operator handle to control the flow of air to the selected abrasion device. Normally closed, the cartridge valve will only allow fluid passage when the lever is depressed by the operator.
A dual manifold design provides entry of pressurized air into a first manifold, which is divided into 3 channels. A power switch controls the overall operational state and controls fluid flow to OPC cartridge valves, a throttled end effector air supply, and a vacuum air supply for dust removal.
The combination of features provides a robust, ergonomic, and highly efficient stand-up abrading machine compared to those in the prior art. Its lightweight allows better mobility during operation and efficient maneuverability when being transported. Stress for the operator is reduced by provision of an ideal orientation in addition to reducing impact on the operator from vibration.
The construction of the invention allows provision of different embodiments to address a variety of circumstances. One additional embodiment can be used for situations where the surface to be abraded is closer to the operator. In this embodiment the central shaft will be shorter than, for instance, the longer shaft employed in a machine to be used for abrading a floor on which the operator stands. In this additional embodiment the central shaft is shorter and the angles of the handle bars and the end effector are changed to allow the operator to conveniently abrade a surface closer to the operator.
With reference to
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With reference to
Air for powering an end effector is directed through the throttle control 24 to opening 46 for connection to an opening in the distal manifold as will be described below.
Air for operating a vacuum system is directed to opening 48 for connection to the inlet of an air-operated conveyor to be described below.
Vacuum opening 49 receives the upper end of the air-operated conveyor 64 and is connected through an internal channel (not shown) to the dust bag 14 shown in
Tube connector 58 receives a tube (not shown) also in the cavity inside the central part 18 of the shaft 6 that is connected to outlet 44a for receiving air from the valve operated by lever 26 and directing it to an valve (not shown) inside the distal manifold that controls passage of air from opening 54 to an end effector.
Modifications within the scope of the appended claims will be apparent to those of skill in the art.
Claims
1. Apparatus for abrading surfaces comprising a first manifold mounted proximate one end of a shaft, and a second manifold mounted distal to said one end of the shaft, wherein said first and second manifolds receive and distribute a fluid under positive pressure and vacuum pressure, and said shaft is connected to said first and second manifolds and includes fluid pathways to conduct air and vacuum flows of said fluid between said manifolds, and an end effector for treating surfaces.
2. Apparatus according to claim 1 wherein said first manifold comprises a connector for receiving a fluid under pressure, an outlet for providing said fluid to said end effector, and at least one outlet for providing said fluid to one or more power control switches.
3. Apparatus according to claim 2 wherein said first manifold comprises a power control lever that adjusts the fluid directed to said end effector.
4. Apparatus according to claim 2 further comprising a fluid operated conveyor and said first manifold includes an outlet for providing said fluid to an inlet of said fluid operated conveyor.
5. Apparatus according to claim 4 wherein said second manifold includes an inlet for receiving said fluid from said first manifold and distributing said fluid to an outlet for supplying said fluid to said end effector.
6. Apparatus according to claim 4 wherein said fluid operated conveyor is mounted to said second manifold.
7. Apparatus wherein said shaft is extruded aluminum.
Type: Application
Filed: Sep 27, 2021
Publication Date: Mar 31, 2022
Inventors: James BITTORF (Rockville, MD), John WENTZ (Rockville, MD)
Application Number: 17/485,839