Mechanical Claims

Claims in the mechanical arts can also be creatively drafted using semi-functional language and mental steps. One trick is to claim some physical characteristic (e.g., length, weight) as being "sufficient" to achieve a particular goal. For example:

1. A dispenser for powder or granular material comprising:

a. a hopper for containing powder or granular material having a bottom member of substantially arcuate configuration, said bottom member including a plurality of openings therethrough and throughout the length thereof;

b. a wiper extending substantially the length of said bottom member, said wiper comprising a rotatable shaft having mounted thereon a plurality of contiguous wiper elements, each wiper including at least one blade having a length sufficient for contacting the bottom member at said openings and offset from a contiguous wiper blade; and

c. a drive for rotating said shaft .

Another trick is to claim the invention from several different perspectives. The claims below add address the same substantive invention, but do so from the different perspectives of the length of the compression and power strokes, (claim 1) movement of the crank pin, (claim 7) the use of planetary gears, (claim 11) and in another patent the noncircular shape of the path traveled by the crankpin .

1. An internal combustion engine comprising a piston reciprocating in a cylinder, said piston having a compression stroke and a power stroke having fixed lengths, wherein the length of the compression stroke is less than the length of the power stroke.

7. A method of increasing the efficiency of a device producing usable power from internal combustion, the method comprising:

providing the device with a piston, a cylinder, a connecting rod, a crank pin, and a rotating crankshaft, operably connected such that the piston reciprocates within the cylinder, and energy from fuel combusted in the cylinder causes the crankshaft to rotate; and

moving the crank pin in a manner that the piston has two top dead center points and two bottom dead center points during each 360 degree rotation of the crankshaft.

11. A reciprocating internal combustion engine comprising:

a first gear carrying a crank pin;

a second gear coupled in a planetary relationship with respect to said first gear such that said crank pin travels in a substantially hypocycloid path, said hypocycloid path completed during a single 360 degree rotation of the engine;

wherein the first and second gears have an effective gear ratio of 1:3; and

the first and second gears define a peripheral axis of rotation and a central axis of revolution, the peripheral axis revolves in a circular motion about the central axis of revolution to define a radius r, and the crank pin is spaced from the peripheral axis of rotation at a distance greater than r.

1. A device comprising:

a first gear carrying a crank pin;

a second gear more than twice the size of said first gear and coupled in a planetary relationship with respect to said first gear such that said crank pin travels in one of a substantially triangular, quadrilateral and pentagonal paths.

Still another trick is to claim minor distinctions that are added to a product solely for the purpose of providing patentable subject matter. For example, in desktop computer printers the profit lies in the cartridges rather than the printers, but the cartridges are easy for competitors to knock off. A powerful strategy is to design a cartridge that relies upon some completely unnecessary feature, and then patent that feature. The following claim appears to follow that strategy by claiming a mechanism that (completely unnecessarily) couples operation of the cartridge with movement of the paper advance.

1. An ink-jet printer comprising: an ink cartridge; a recording head; an ink supply passage connecting the ink cartridge to the recording head; a valve opening/closing mechanism for opening or closing the ink supply passage; a paper feed driving mechanism provided along a part of the ink supply passage and mechanically linked to the valve opening/closing mechanism, the valve opening/ closing mechanism operable to open the ink supply passage as a result of a rotation of the paper feed driving mechanism.