Abstract: A universal motor includes a commutator brush with a cavity for sheltering a constant force spring from a wire shunt. In some examples, the cavity can be formed by milling a blind hole into the brush such that an axial centerline of the hole is perpendicular to the brush's length. The cavity is near the back end of the brush, at the end farthest away from the commutator, but is also slightly forward to leave a rear portion of the brush to serve as a barrier between the wire shunt and the spring. The diameter of the cavity is slightly larger than the width of the brush, so the cavity creates a slot in the side of the brush. The slot allows part of the spring to reach out beyond the cavity to where the spring can hook onto a front edge of a stationary sleeve that supports the brush.

Abstract: A universal motor includes a commutator brush with a cavity for sheltering a constant force spring from a wire shunt. In some examples, the cavity can be formed by milling a blind hole into the brush such that an axial centerline of the hole is perpendicular to the brush's length. The cavity is near the back end of the brush, at the end farthest away from the commutator, but is also slightly forward to leave a rear portion of the brush to serve as a barrier between the wire shunt and the spring. The diameter of the cavity is slightly larger than the width of the brush, so the cavity creates a slot in the side of the brush. The slot allows part of the spring to reach out beyond the cavity to where the spring can hook onto a front edge of a stationary sleeve that supports the brush.

Abstract: HVLP (High Velocity Low Pressure) motor-driven fans and other types of fans, blowers and vacuums include one or more features for minimizing vibration and eliminating other causes of fan or motor failure. Examples of such features include a fan blade with a particularly short tail section, a fan wheel spacer with a counterbore in an axial face of the spacer, and a small boss or thin shim adjacent to a screw that clamps an assembly of stator laminations between two motor brackets. The tail section, being relatively short, resists bending during high speed rotation, thereby preventing vibration. The counterbore in the spacer provides the spacer with resilience for maintaining an axial clamping force even as part dimensions change due to thermal expansion. The boss or shim allows the screw to tightly clamp the stator laminations without cracking either of the motor brackets.

Abstract: HVLP (High Velocity Low Pressure) motor-driven fans and other types of fans, blowers and vacuums take advantage of different thermal and mechanical properties of dissimilar materials used in the motor-driven fans. The dissimilar materials include aluminum for a stacked arrangement of fan wheels and spacers, steel for a shaft that supports the fan wheels and spacers, and a polymeric adhesive. In some examples, the polymeric adhesive is trapped between the aluminum and steels parts. Compared to steel and aluminum, the adhesive has a relatively high coefficient of thermal expansion but relatively low strength such that thermal expansion of the adhesive exerts additional clamping pressure during startup and during high temperature operation. The additional clamping pressure reduces vibration and eliminates other causes of fan or motor failure.

Abstract: HVLP (High Velocity Low Pressure) motor-driven fans and other types of fans, blowers and vacuums include one or more features for minimizing vibration and eliminating other causes of fan or motor failure. Examples of such features include a fan blade with a particularly short tail section, a fan wheel spacer with a counterbore in an axial face of the spacer, and a small boss or thin shim adjacent to a screw that clamps an assembly of stator laminations between two motor brackets. The tail section, being relatively short, resists bending during high speed rotation, thereby preventing vibration. The counterbore in the spacer provides the spacer with resilience for maintaining an axial clamping force even as part dimensions change due to thermal expansion. The boss or shim allows the screw to tightly clamp the stator laminations without cracking either of the motor brackets.

Abstract: HVLP (High Velocity Low Pressure) motor-driven fans and other types of fans, blowers and vacuums take advantage of different thermal and mechanical properties of dissimilar materials used in the motor-driven fans. The dissimilar materials include aluminum for a stacked arrangement of fan wheels and spacers, steel for a shaft that supports the fan wheels and spacers, and a polymeric adhesive. In some examples, the polymeric adhesive is trapped between the aluminum and steels parts. Compared to steel and aluminum, the adhesive has a relatively high coefficient of thermal expansion but relatively low strength such that thermal expansion of the adhesive exerts additional clamping pressure during startup and during high temperature operation. The additional clamping pressure reduces vibration and eliminates other causes of fan or motor failure.

Abstract: A rechargeable air-moving system (e.g., a hair drier, a pet groomer, a liquid sprayer, a vacuum cleaner, etc.) has a rather high voltage universal motor powered by a relatively low voltage rechargeable battery. The battery provides the benefits of portability and low-voltage safety, and the high voltage motor provides the benefits of speed, being lightweight and compact. In some examples, high voltage from a domestic AC power source is reduced to low voltage to charge the battery, and then a step-up converter increases the low DC voltage from the battery to a much higher voltage for the motor. The magnitude of the high voltage from the converter is comparable to the high voltage of the domestic AC power source. The relatively high voltage from the converter powers a high voltage universal motor that is lighter and more compact than a low voltage universal motor of equivalent power.

Abstract: A paint sprayer includes a motor-driven multi-stage turbine for compressing air, which subsequently flows through a venturi in a paint gun to draw in paint or some other liquid from a canister. To prevent the high-pressure air from expelling lubricant from the motor's inboard bearing, a pressure responsive annular seal axially deflects and sealingly engages an axial face of the bearing. To avoid subjecting the seal and bearing to excess air pressure and temperature created by the turbine, a bypass bleed line diverts some air to atmosphere when the paint gun is closed.

Abstract: A seal actuated by generally atmospheric pressure helps protect the motor bearing of a vacuum appliances, such as a dry air vacuum cleaner, a wet/dry vacuum cleaner, a water extractor (e.g., carpet cleaner), etc. The generally atmospheric air pressure on a motor side of the seal and a vacuum on an opposite turbine side of the seal urges the seal in an axial direction toward an impeller of the vacuum appliance and presses the seal firmly against an axially abutting sealing surface. Sliding sealing contact between a broad axial surface of the seal and the abutting sealing surface helps prolong the life of the seal and the bearing.

Abstract: A universal motor comprises a stator interposed between a housing and a novel plastic bracket. The plastic bracket is a unitary piece that not only defines a plurality of terminal receptacles but also supports the motor's outboard bearing. In some embodiments, the plastic bracket also includes an integral post for supporting a spring that urges a carbon brush against the motor's commutator.

Abstract: A high-speed universal motor running at over 10,000 or even over 20,000 rpm includes a non-rubbing water repellent sleeve that protects the bearings from moisture damage. Rather than having a sliding contact seal that can quickly wear out under such high speeds, the sleeve is made of material having a low solid surface energy so that the seal material itself repels waters on its own. TEFLON is the preferred material, which is relatively soft, so to prevent the compressibility of the seal from affecting the axial positioning of parts on the motor shaft, the seal is installed such that the seal does not contribute to the critically precise positioning of the shaft and the parts mounted to it. In some embodiments, for example, the relatively soft seal simply overlies a much stiffer, accurately machined metal spacer.

Abstract: For a motor having a plastic bracket, a single-piece ground strap grounds both the motor's stator and rotor. The ground strap has one end fastened to a bearing retainer of the motor, an opposite end connected to a ground wire, and an intermediate section that is compressed between the stator and the housing. The end connected to the bearing retainer grounds the rotor, and the intermediate section grounds the stator. The ground strap is fastened to the motor using fasteners that already exist in an otherwise identical but ungrounded motor. In some cases, a combination bearing retainer and ground strap is blanked and formed as a unitary piece.

Abstract: A motor, particularly suited for carpet cleaners and other wet vacuuming appliances, includes a motor housing with a stepped bore. The stepped bore is part of a bearing/seal assembly that simultaneously clamps a bearing and compresses a seal member. The assembly maintains the motor's commutator at a substantially fixed axial location relative to the commutator's brushes, regardless of the extent to which the seal is compressed and regardless of any subsequent creep of the seal.

Abstract: A handheld vacuum cleaner is provided that has a motor mounted with the rotational axis of its shaft parallel to the rotational axis of the rotating brush. The vacuum cleaner motor has an end bell, which is attached to the motor stator, and which holds a motor shaft bearing. The end bell is secured to the vacuum housing with an elastomeric mounting ring to dampen motor vibrations. The need for most motor mounting hardware is eliminated, because the housing supports the motor stator directly. The intake orifice of the vacuum is shaped to lie in two distinct planes, so that flat cleaning surfaces do not obstruct the orifice. The shape of the intake also allows one to clean immediately adjacent to a vertical wall.

Abstract: A brush/shunt assembly for an electric motor is provided. The shunt portion of the assembly is a stranded wire shunt with a joined (e.g., fused) end that can be easily inserted into a slotted terminal. A lubricant can be added to reduce insertion forces.

Abstract: A handheld vacuum cleaner is provided that has a motor mounted with the rotational axis of its shaft parallel to the rotational axis of the rotating brush. The vacuum cleaner motor has an end bell, which is attached to the motor stator, and which holds a motor shaft bearing. The end bell is secured to the vacuum housing with an elastomeric mounting ring to dampen motor vibrations. The need for most motor mounting hardware is eliminated, because the housing supports the motor stator directly. The intake orifice of the vacuum is shaped to lie in two distinct planes, so that flat cleaning surfaces do not obstruct the orifice. The shape of the intake also allows one to clean immediately adjacent to a vertical wall.

Abstract: An air guide and motor housing assembly for use in domestic and commercial vacuum cleaners is described wherein the assembly comprises an air guide having a center detail for engaging the motor housing to facilitate assembly of the components, and reduce creep, turbulence and vibration-induced noise. An air guide for use with a centrifugal fan is described wherein the air guide is mounted on a motor bracket using the same rivets that fasten a bearing assembly to the motor bracket. Alternative embodiments of the device are also described in which a step in an inner fan housing cooperates with a step projecting from the air guide to securely fasten the air guide to the motor assembly, and a center detail on the air guide engages the motor housing to secure the air guide thereto, thereby providing the same advantages.

Abstract: A motor-driven blower, particularly suited for carpet cleaners and other wet vacuuming appliances, includes a rotating separator cup to impede water droplets and foam from being drawn into the blower. The separator cup is removably connected to a spider bracket that is mounted more permanently to one end of the motor shaft. Since the separator cup is not directly connected to the motor shaft, the cup can be removed without disturbing the rest of the blower. Thus, the blower can be run either with or without the separator cup. Moreover, by not attaching the separator cup directly to the motor shaft, the shaft can be made shorter to minimize vibration and noise at high rpm's.