Abstract: A method for treating the surface of the heat dissipation module is provided. The method includes the following steps. First, a heat dissipation module is provided. Next, a nano-material layer is formed on the surface of the heat dissipation module. Thus, the surface of the heat dissipation module is isolated from air and effectively prevented from being oxidized or polluted.

Abstract: A bearing structure includes a cylindrical first member (10), and a second member (20) received in the first member. The first member is made of ceramic sintered material. The first member defines a first axle hole (11), and the first axle hole has a first radius. A chamber (12) is transversely defined through a middle portion of the first member, the chamber receiving the second member therein. The second member is made of metallic sintered material. The second member defines a second axle hole (21), and the second axle hole has a second radius. The first radius of the first axle hole is less than the second radius of the second axle hole. A shaft (30) is rotatably received in the first and second axle holes. When the shaft deviates from a central axis of rotation, the shaft only contacts the first member at the first axle hole.

Abstract: A bearing assembly includes a generally cylindrical main unit (10) made of ceramic material, and two blocks (30) made of sintered metallic material housed in the main unit. The main unit includes a cylindrical sleeve (12), and two opposite protrusions (14) arranged inside the sleeve. Each protrusion defines an inmost first support wall (20), and a through hole (24) that is narrow at a middle portion and flared at opposite ends. A slit (26) is defined in the protrusion between the first support wall and the through hole. The blocks are received in two corresponding cavities (18) defined between the protrusions. Each block defines an inmost second support wall (36). The first and second support walls cooperatively define a bearing bore (22) therebetween for receiving a rotatable shaft. The blocks have good lubricant-retaining characteristics. The highly rigid protrusions can accurately hold the shaft and protect the blocks from excessive abrasion.

Abstract: A bearing device (10) for a motor (12) includes a bearing set (20) and a shaft (14). The bearing set includes first and second bearings (21, 26), which are made of sintered metallic material and ceramic material respectively. An annular recess (24) is defined in one end of the first bearing. The second bearing is received in the recess. Each bearing defines a central hole (22, 27). The central holes have a same diameter. The motor includes a rotor (30), a stator (32), and a bearing sleeve (34). In assembly, one end of the shaft is fixed in a center of the rotor. The second bearing is inserted into the recess. The bearing set is fixed within the bearing sleeve. The stator is fixed around the bearing sleeve. The shaft is rotatably received in the central holes. During operation, the shaft rotates smoothly and stably in the bearing set.

Abstract: A fan includes a frame (10), a stator (22), an impeller (40), and an oil retainer (70). The frame includes a sleeve (14) having a bearing (20) secured therein. The stator surrounds the sleeve, and the impeller surrounds the stator. The impeller includes inner and outer rings (46, 45). The oil retainer includes a large cylinder (72) fittingly received between the rings to form a seal between the large cylinder and the outer ring, and a small cylinder (74) received in the stator. A sealed chamber (49) is thus defined between the large cylinder and the impeller. A shaft (48) is fixedly secured in the impeller, and extends through the oil retainer and the bearing. A gap (50) is defined between the shaft and the small cylinder. In operation, lubricating oil originating from the bearing passes through the gap to the sealed chamber, and flows back to the bearing.

Abstract: A bearing device (10) for a motor (12) includes a bearing set (20) and a shaft (14). The bearing set includes first and second bearings (21, 26), which are made of sintered metallic material and ceramic material respectively. An annular recess (24) is defined in one end of the first bearing. The second bearing is received in the recess. Each bearing defines a central hole (22, 27). The central holes have a same diameter. The motor includes a rotor (30), a stator (32), and a bearing sleeve (34). In assembly, one end of the shaft is fixed in a center of the rotor. The second bearing is inserted into the recess. The bearing set is fixed within the bearing sleeve. The stator is fixed around the bearing sleeve. The shaft is rotatably received in the central holes. During operation, the shaft rotates smoothly and stably in the bearing set.

Abstract: A fan includes a frame (10), a stator (22), an impeller (40), and an oil retainer (70). The frame includes a sleeve (14) having a bearing (20) secured therein. The stator surrounds the sleeve, and the impeller surrounds the stator. The impeller includes inner and outer rings (46, 45). The oil retainer includes a large cylinder (72) fittingly received between the rings to form a seal between the large cylinder and the outer ring, and a small cylinder (74) received in the stator. A sealed chamber (49) is thus defined between the large cylinder and the impeller. A shaft (48) is fixedly secured in the impeller, and extends through the oil retainer and the bearing. A gap (50) is defined between the shaft and the small cylinder. In operation, lubricating oil originating from the bearing passes through the gap to the sealed chamber, and flows back to the bearing.

Abstract: A bearing assembly includes a generally cylindrical main unit (10) made of ceramic material, and two blocks (30) made of sintered metallic material housed in the main unit. The main unit includes a cylindrical sleeve (12), and two opposite protrusions (14) arranged inside the sleeve. Each protrusion defines an inmost first support wall (20), and a through hole (24) that is narrow at a middle portion and flared at opposite ends. A slit (26) is defined in the protrusion between the first support wall and the through hole. The blocks are received in two corresponding cavities (18) defined between the protrusions. Each block defines an inmost second support wall (36). The first and second support walls cooperatively define a bearing bore (22) therebetween for receiving a rotatable shaft. The blocks have good lubricant-retaining characteristics. The highly rigid protrusions can accurately hold the shaft and protect the blocks from excessive abrasion.

Abstract: A retaining device (10) includes a shaft (12), and a fastener (30) attached to an end of the shaft. The shaft comprises a guide portion (14) at an end thereof for guiding the shaft to enter the fastener. An annular groove (16) is defined in a bottom portion of the shaft above the guide portion. The fastener is bent from a single strip of stainless steel material. The fastener is generally an equilateral triangle, and includes three straight sides (31, 32, 33). Two U-shaped resilient portions (34) are respectively formed at two junctions of the sides. A first end portion (35) extends from a free end of one of the sides. A second end portion (36) extends from a free end of another of the sides, parallel to and closely opposing the first end portion. The fastener is snappingly and securely received in the groove of the shaft.

Abstract: A bearing structure includes a cylindrical first member (10), and a second member (20) received in the first member. The first member is made of ceramic sintered material. The first member defines a first axle hole (11), and the first axle hole has a first radius. A chamber (12) is transversely defined through a middle portion of the first member, the chamber receiving the second member therein. The second member is made of metallic sintered material. The second member defines a second axle hole (21), and the second axle hole has a second radius. The first radius of the first axle hole is less than the second radius of the second axle hole. A shaft (30) is rotatably received in the first and second axle holes. When the shaft deviates from a central axis of rotation, the shaft only contacts the first member at the first axle hole.