Dental handpieces, motors, couplers and other dental instruments and methods having multiple very small, high output, LEDs in a single lamp assembly to facilitate incorporation of a plurality of wavelengths emitted from these devices to allow dentists to select between the benefits of multiple wavelength light outputs to the working area in a single device.

When the compressed air is not applied, an inclined surface, which is positioned at an upstream side with respect to the supply direction of the compressed air, of the lip part is in contact with the inclined surface of the inner ring. When the compressed air is applied, a contact area between the inclined surface, which is positioned at the upstream side with respect to the supply direction of the compressed air, of the lip part and the inclined surface of the inner ring becomes smaller, as compared to when the compressed air is not applied.

A zero-suckback device for a disposable high-speed turbine dental drill handpiece includes two units respectively installed at two ends of the head of the handpiece. On one side of the handpiece head where a drill pin is installed, one unit consists of an elastic shaft sealing casing which is centrally embedded with a central framework made of hard substances and a non-elastic shaft sealing casing, and a lip portion of the elastic shaft sealing casing fits a wind wheel shaft with a tapered end. On the cover side of the handpiece head and between a button housing and a head housing, an O-shaped sealing ring is installed, and a one-way ball valve is installed at the center of the button housing. Suckback prevention measures are adopted at both sides of the handpiece head, so matters sucked back can be controlled to be a very low level, nearly zero.

The rolling bearing includes: an outer ring having an outer ring raceway surface on an inner peripheral surface; an inner ring having an inner ring raceway surface on an outer peripheral surface; rolling elements rotatably arranged between the outer ring raceway surface and the inner ring raceway surface; and a seal member that is fixed to a seal attachment groove formed in an axially end portion of the outer ring by a snap ring and seals an axially end portion of a bearing internal space between the outer ring and the inner ring, in which an outer diameter of the seal member is larger than an outer diameter of the snap ring in the seal attachment groove, and in which a radially outer end portion of the seal member is sandwiched between an inner peripheral surface of the seal attachment groove and an outer peripheral surface of the snap ring.

The rolling bearing includes: an outer ring having an outer ring raceway surface on an inner peripheral surface; an inner ring having an inner ring raceway surface on an outer peripheral surface; rolling elements rotatably arranged between the outer ring raceway surface and the inner ring raceway surface; and a seal member that is fixed to a seal attachment groove formed in an axially end portion of the outer ring by a snap ring and seals an axially end portion of a bearing internal space between the outer ring and the inner ring, in which an outer diameter of the seal member is larger than an outer diameter of the snap ring in the seal attachment groove, and in which a radially outer end portion of the seal member is sandwiched between an inner peripheral surface of the seal attachment groove and an outer peripheral surface of the snap ring.

The aim of the invention disclosed herein is to control and regulate the stiffness and flexibility of an endodontic file exploiting its super-elastic and shape-memory characteristics. This result is achievable thanks to temperature-induced phase transformations of the file performed by a proper heating and cooling system managed by a control system in a handpiece. Different designs of the apparatus implementing the proposed solution are disclosed.

The overload protection device used on a high-speed dental handpiece includes a valve body, a piston, an elastic member, and a valve plug. The valve body is provided with an air chamber and an air intake passage in communication with each other. The piston is arranged in the air chamber. The valve plug is arranged at an end of the air chamber away from the air intake passage and is connected with the valve body. The elastic member is arranged between the piston and the valve plug. An outer surface of the valve body is provided with a plurality of air discharging holes which is in communication with the air chamber. The piston is capable of opening or closing the air discharging holes when moving vertically within the air chamber. The present invention further discloses a high-speed dental handpiece with an overload protection device.

The overload protection device used on a high-speed dental handpiece includes a valve body, a piston, an elastic member, and a valve plug. The valve body is provided with an air chamber and an air intake passage in communication with each other. The piston is arranged in the air chamber. The valve plug is arranged at an end of the air chamber away from the air intake passage and is connected with the valve body. The elastic member is arranged between the piston and the valve plug. An outer surface of the valve body is provided with a plurality of air discharging holes which is in communication with the air chamber. The piston is capable of opening or closing the air discharging holes when moving vertically within the air chamber. The present invention further discloses a high-speed dental handpiece with an overload protection device.

Flow-driven dental instrument (1), comprising a grip part (2), a head part (3), a media line (4), and a fastening means (8), wherein the grip part (2) is constructed in the form of a sleeve with two ends and a media connection (5) is disposed on the first end. At the second end, the head part (3) projects at least partially into the grip part (2). A first end of the media line (4) is connected to the head part (3) and the media line (4) extends from the head part (3) through the grip part (2) to the media connection (5). The fastening means (8) comprises a sleeve (9) having an external thread and a nut (10) having an internal thread, wherein the sleeve (9) is connected to the outer wall of the media line (4) in a material-locking manner and, at least in a direction toward the head part (3), the nut is held in the grip part (2) in a fixed position.

Flow-driven dental instrument (1), comprising a grip part (2), a head part (3), a media line (4), and a fastening means (8), wherein the grip part (2) is constructed in the form of a sleeve with two ends and a media connection (5) is disposed on the first end. At the second end, the head part (3) projects at least partially into the grip part (2). A first end of the media line (4) is connected to the head part (3) and the media line (4) extends from the head part (3) through the grip part (2) to the media connection (5). The fastening means (8) comprises a sleeve (9) having an external thread and a nut (10) having an internal thread, wherein the sleeve (9) is connected to the outer wall of the media line (4) in a material-locking manner and, at least in a direction toward the head part (3), the nut is held in the grip part (2) in a fixed position.