Abstract: Variable resistance devices and methods are disclosed. Resistance may be determined based on velocity of movement of a component in a variable resistance device. A variable resistance device may include a stator having a tapered internal bore and a plug disposed for longitudinal movement relative to the tapered internal bore to control resistance force. The tapered internal bore in the stator may be designed to yield a linear relationship between change in force and change in longitudinal movement of the plug relative to the tapered internal bore. The plug may be connected to a longitudinal rod movably disposed within a sleeve. The velocity at which the sleeve moves may be used to control movement of the plug relative to the tapered bore, and to thereby control resistance force. Variable resistance devices may be included as part of exercise equipment to control resistance force presented to a person using the equipment.

Abstract: Variable resistance devices and methods are disclosed. Resistance may be determined based on velocity of movement of a component in a variable resistance device. A variable resistance device may include a stator having a tapered internal bore and a plug disposed for longitudinal movement relative to the tapered internal bore to control resistance force. The tapered internal bore in the stator may be designed to yield a linear relationship between change in force and change in longitudinal movement of the plug relative to the tapered internal bore. The plug may be connected to a longitudinal rod movably disposed within a sleeve. The velocity at which the sleeve moves may be used to control movement of the plug relative to the tapered bore, and to thereby control resistance force. Variable resistance devices may be included as part of exercise equipment to control resistance force presented to a person using the equipment.

Abstract: An apparatus and method for separating water from an oil-and-water mixture includes at least two elongated separator vessels oriented at an incline and connected to one another so that an upwardly flowing oil predominant fluid passes from the first separator vessel to the second separator vessel where further electrostatic separation of water from the oil predominant fluid occurs. Each vessel has an electrode at its upper end preferably connected to a different voltage source. The inlet to each vessel is located relative to the electrode to provide an up flow or a down flow vessel. Additionally, the first vessel may be at a different elevation than the second vessel. An additional vessel may be included with output from the first vessel bypassing the additional vessel, the second vessel, or both. Baffles may be added in the water collection portion of each vessel to reduce turbulence and settling distance.

Abstract: An apparatus and method for separating water from an oil-and-water mixture includes at least two elongated separator vessels oriented at an incline and connected to one another so that an upwardly flowing oil predominant fluid passes from the first separator vessel to the second separator vessel where further electrostatic separation of water from the oil predominant fluid occurs. Each vessel has an electrode at its upper end preferably connected to a different voltage source. The inlet to each vessel is located relative to the electrode to provide an up flow or a down flow vessel. Additionally, the first vessel may be at a different elevation than the second vessel. An additional vessel may be included with output from the first vessel bypassing the additional vessel, the second vessel, or both. Baffles may be added in the water collection portion of each vessel to reduce turbulence and settling distance.

Abstract: An earth boring drill bit design for alleviating balling varies the junk slot depth in junk slots subject to balling from the other junk slots. Using variable depth bit bodies enhances the hydraulic characteristics of the bit as well as assists in the placement of the nozzles for machining purposes. This flexibility optimizes the area changes along the ducts required by the bit's operation.