A blower assembly includes, but is not limited to, a blower housing defining a blower chamber and including a gas inlet and a gas outlet; a first rotor positioned within the blower chamber and adapted for rotation therein, the first rotor including a first shaft and at least two lobes defining a first lobe profile; and a second rotor positioned within the blower chamber and adapted for rotation therein, the second rotor including a second shaft and at least two lobes defining a second lobe profile, wherein the first and second rotors are formed from a metal having a coefficient of thermal expansion from about 1 (10.sup.?6 in/in*K) to about 13 (10.sup.?6 in/in*K), and wherein at least one of the outer surface of the first rotor, the outer surface of the second rotor, or the blower chamber includes a coating.

An enhanced elastomeric stator assembly and method of making the same is disclosed. The elastomeric stator may be structurally, thermally, and/or chemically enhanced through the incorporation of graphene particles, cross-linkable polymers, coupling agents that extend cross-links, and by the reduction of filler material. The graphene particles can be incorporated in functionalized or non-functionalized form or in a combination thereof, the functionalized graphene increasing the number of cross-links in the overall structure, thereby enhancing the structural robustness of the elastomeric stator. The compound can be formulated to have a relatively low viscosity and other characteristics that allow the material to flow through a mold cavity.

A metal component which has a face which during use is thermally or mechanically more highly loaded than the environment thereof and which is at least partially covered with a glaze or enamel layer and a method for the production thereof. The metal component requires no specific limitations during the thermal processing operation and nonetheless ensures optimum protection for the surfaces which are highly loaded during use. The glaze or enamel layer contains, with respect to the enamel frit used to produce the enamel coating, from 2 to 35% by weight of an admixture of particles which consist of at least one material from glass, organic plastics materials, and synthetic oxide mixtures or melts, which each have a thermal expansion coefficient of a maximum of 5010.sup.7 K.sup.1 and a melting temperature of at least 500 C.

A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.

Scroll compressor designs are provided to minimize vibration, sound, and noise transmission. The scroll compressor has a bearing housing, and orbiting and non-orbiting scroll members. The non-orbiting scroll member has a radially extending flanged portion with at least one aperture substantially aligned with the axially extending bore. At least one fastener is disposed within the aperture and the bore. A sound isolation member contacts at least one of the non-orbiting scroll member, the fastener, or the bearing housing, to reduce or eliminate noise transmission. The sound isolation member may be formed of a polymeric composite having an acoustic impedance value greater than the surrounding materials. The sound isolation member may be an annular washer, an O-ring, or a biasing member, by way of non-limiting example. In other variations, fluid passages are provided within the fastener and/or bearing housing to facilitate entry of lubricant oil to further dampen sound and noise.

Scroll compressor designs are provided to minimize vibration, sound, and noise transmission. The scroll compressor has a bearing housing, and orbiting and non-orbiting scroll members. The non-orbiting scroll member has a radially extending flanged portion with at least one aperture substantially aligned with the axially extending bore. At least one fastener is disposed within the aperture and the bore. A sound isolation member contacts at least one of the non-orbiting scroll member, the fastener, or the bearing housing, to reduce or eliminate noise transmission. The sound isolation member may be formed of a polymeric composite having an acoustic impedance value greater than the surrounding materials. The sound isolation member may be an annular washer, an O-ring, or a biasing member, by way of non-limiting example. In other variations, fluid passages are provided within the fastener and/or bearing housing to facilitate entry of lubricant oil to further dampen sound and noise.

Scroll compressor designs are provided to minimize vibration, sound, and noise transmission. The scroll compressor has a bearing housing, and orbiting and non-orbiting scroll members. The non-orbiting scroll member has a radially extending flanged portion with at least one aperture substantially aligned with the axially extending bore. At least one fastener is disposed within the aperture and the bore. A sound isolation member contacts at least one of the non-orbiting scroll member, the fastener, or the bearing housing, to reduce or eliminate noise transmission. The sound isolation member may be formed of a polymeric composite having an acoustic impedance value greater than the surrounding materials. The sound isolation member may be an annular washer, an O-ring, or a biasing member, by way of non-limiting example. In other variations, fluid passages are provided within the fastener and/or bearing housing to facilitate entry of lubricant oil to further dampen sound and noise.

A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.

A vacuum booster assembly includes, but is not limited to, a booster housing defining a booster chamber and including a gas inlet and a gas outlet; a first rotor positioned within the booster chamber and adapted for rotation therein, the first rotor including a first shaft and at least two lobes defining a first lobe profile; and a second rotor positioned within the booster chamber and adapted for rotation therein, the second rotor including a second shaft and at least two lobes defining a second lobe profile, wherein the first and second rotors are formed from a metal having a coefficient of thermal expansion from about 1 (10.sup.6 in/in*K) to about 13 (10.sup.6 in/in*K), and wherein at least one of the outer surface of the first rotor, the outer surface of the second rotor, or the booster chamber includes a coating.

A blower assembly includes, but is not limited to, a blower housing defining a blower chamber and including a gas inlet and a gas outlet; a first rotor positioned within the blower chamber and adapted for rotation therein, the first rotor including a first shaft and at least two lobes defining a first lobe profile; and a second rotor positioned within the blower chamber and adapted for rotation therein, the second rotor including a second shaft and at least two lobes defining a second lobe profile, wherein the first and second rotors are formed from a metal having a coefficient of thermal expansion from about 1 (10.sup.6 in/in*K) to about 13 (10.sup.6 in/in*K), and wherein at least one of the outer surface of the first rotor, the outer surface of the second rotor, or the blower chamber includes a coating.