Abstract: A dental handpiece is disclosed which has a head housing, a gear shaft having a gear part with gear teeth and a shaft part extending from the gear part, and a dust control seal sealingly fit on the circumferential surface of the shaft part of the gear shaft. The dust control seal is an annular member, and has a seal body, a first lip projecting radially inwardly from the seal body, and a second lip projecting radially inwardly from the seal body above and spaced apart from the first lip, with a space defined between a contact area between the first lip and the shaft part, and a contact area between the second lip and the shaft part.

Abstract: A dental handpiece is disclosed which has a head housing, a gear shaft having a gear part with gear teeth and a shaft part extending from the gear part, and a dust control seal sealingly fit on the circumferential surface of the shaft part of the gear shaft. The dust control seal is an annular member, and has a seal body, a first lip projecting radially inwardly from the seal body, and a second lip projecting radially inwardly from the seal body above and spaced apart from the first lip, with a space defined between a contact area between the first lip and the shaft part, and a contact area between the second lip and the shaft part.

Abstract: The present invention provides eyeglasses including a frame and an arm connectable to the frame. The eyeglasses include a magnetic hinge connecting the arm to the frame. The magnetic hinge includes a first housing having an first inner cavity and a first outer protruding edge having a plurality of extending flanges disposed thereon, a first magnet disposed inside the first housing, a central washer including at least a portion of the central washer having magnetic attraction capabilities, a second housing having a second inner cavity and an inner lip portion radially disposed within the second inner cavity and a second magnet disposed inside the second housing. The magnetic hinge is magnetically held in place by the magnetic attraction between the first magnet and the second magnet via the central washer and the engagement of the extending flanges within the inner lip portion.

Abstract: The present invention provides eyeglasses including a frame and an arm connectable to the frame. The eyeglasses include a magnetic hinge connecting the arm to the frame. The magnetic hinge includes a first housing having an first inner cavity and a first outer protruding edge having a plurality of extending flanges disposed thereon, a first magnet disposed inside the first housing, a central washer including at least a portion of the central washer having magnetic attraction capabilities, a second housing having a second inner cavity and an inner lip portion radially disposed within the second inner cavity and a second magnet disposed inside the second housing. The magnetic hinge is magnetically held in place by the magnetic attraction between the first magnet and the second magnet via the central washer and the engagement of the extending flanges within the inner lip portion.

Abstract: The object of the invention is to provide a structure for eyeglass parts which assures excellent connecting strength between the metal core material and the rubber-like elastic material and is free from easy separation of connection surfaces of both materials. Eyeglass parts such as a temple, lens frame, bridge, and top bar are composed by integrally connecting rubber-like elastic material 10 to metal core material 2. Metal core material 2 of temple body 1 is provided with a plurality of through-holes 6 spaced apart in the lengthwise direction, and rubber-like elastic material 10 injection-molded in such manner as to envelop metal core material 2 is integrally connected to metal core material 2 via through-holes 6.

Abstract: A method and apparatus for drilling glass using a drill and drill bit. The method utilizes a drill bit having a plurality of shaft diameters, and being provided with a plurality of types of abrasives. By providing a coarser abrasive on a narrow portion of the bit, and finer abrasives on a wider portion of the bit, drilling can be accomplished while reducing the incidents of micro fracture in the glass being drilled. Providing an even narrower connection shaft between the two cutting portions of the drill bit further facilitates reduction in micro fractures created during the drilling process.

Abstract: The frame of a pair of multiple-focus spectacles has temples (7) each connected by a vertical swiveling mechanism (8) with a horizontal pivot (30), to a web (5) on the outer side of a forward frame part (4). A retainer built in this mechanism has a pawl (19) adjoining to the frame part (4), and an arcuate row of notches (23, 24, 25) are formed within the temple (7) around the pivot (30) so as to alternatively engage with the pawl (19). A compression spring (27) urges the pawl to be retained in the chosen notch, and the temple (7) can be pulled simply against the spring so that the pawl (19) disengages from one notch (23, 24, 25) and then engages with another notch. Each temple (7) is surely retained either at any downwardly slanted position or at the normal straight position relative to the frame part (4).