The present disclosure relates generally to the field of tissue removal and more particularly to methods and devices for use in medical applications involving selective tissue removal. One exemplary method includes the steps of providing a tissue cutting instrument capable of distinguishing between target tissue to be removed and non-target tissue, urging the instrument against the target tissue and the non-target tissue, and allowing the instrument to cut the target tissue while automatically avoiding cutting of non-target tissue. Various tools for carrying out this method are also described.

The invention relates mainly to an assembly comprising: a combustion engine ring gear having a plurality of teeth, the said ring gear being defined by a modulus and a pressure angle, a starter comprising a pinion (31) able to engage with the said ring gear of the said combustion engine, the said pinion (31) having a plurality of teeth (42) is defined by a modulus (Mp) and a pressure angle (alpha_p), characterized in that a pinion product which is the product of the modulus (Mp) of the said pinion (31) and the cosine of the pressure angle (alpha_p) of the said pinion (31) is greater than a ring-gear product equal to the product of the modulus of the said ring gear and the cosine of the pressure angle of the said ring gear.

The invention relates mainly to an assembly comprising: a combustion engine ring gear having a plurality of teeth, the said ring gear being defined by a modulus and a pressure angle, a starter comprising a pinion (31) able to engage with the said ring gear of the said combustion engine, the said pinion (31) having a plurality of teeth (42) is defined by a modulus (Mp) and a pressure angle (alpha_p), characterized in that a pinion product which is the product of the modulus (Mp) of the said pinion (31) and the cosine of the pressure angle (alpha_p) of the said pinion (31) is greater than a ring-gear product equal to the product of the modulus of the said ring gear and the cosine of the pressure angle of the said ring gear.

A balance shaft structure includes a balance shaft including a balance weight, a driven gear to rotate the balance shaft by being engaged with a drive gear, a scissors mechanism, whose position in an axial direction is regulated, including a scissors gear to reduce backlash between the drive gear and the driven gear and an axially urging member to urge the scissors gear toward the driven gear in the axial direction, a first regulating portion to regulate an axially inner position of the scissors mechanism, and a second regulating portion fixed to the balance shaft on a side close to the shaft end part of the balance shaft beyond the first regulating portion and configured to regulate an axially outer position of the scissors mechanism.

A wave gear apparatus comprises a spline having top, bottom, exterior, and interior surfaces. A plurality of spline teeth extend from the interior surface toward a center axis. A wave generator is rotatably disposed in the spline. A belt extends about the wave generator. The belt includes a plurality of belt teeth extending radially outwardly from the belt whereby a total number of the belt teeth is less than a total number of the spline teeth. An output member defines a recess receiving the wave generator and the belt whereby, in response to a rotational movement from the wave generator, the output member rotates in a direction same or opposite of the wave generator. A vehicle lifting system including the wave gear apparatus is also disclosed herein.

A drive transmission device includes a first gear, a cam configured to rotate in interrelation with rotation of the first gear and capable of changing a state of two members between a pressed state and a pressure-released state, a pressing member configured to press the cam, and a second gear configured to transmit drive to the first gear in engagement with the first gear. At least one of the first and second gears includes first teeth provided at positions corresponding to an engaging region in which the first gear is engaged with the second gear when the state of the two members is changed from the pressure-released state to the pressed state and includes second teeth provided at positions corresponding to a region other than the engaging region. Tooth thicknesses of the first teeth are thicker than tooth thicknesses of the second teeth.

A drive transmission device includes a first gear, a cam configured to rotate in interrelation with rotation of the first gear and capable of changing a state of two members between a pressed state and a pressure-released state, a pressing member configured to press the cam, and a second gear configured to transmit drive to the first gear in engagement with the first gear. At least one of the first and second gears includes first teeth provided at positions corresponding to an engaging region in which the first gear is engaged with the second gear when the state of the two members is changed from the pressure-released state to the pressed state and includes second teeth provided at positions corresponding to a region other than the engaging region. Tooth thicknesses of the first teeth are thicker than tooth thicknesses of the second teeth.

The present disclosure relates to an apparatus for operating a main shaft of a machine tool, the apparatus including: an input unit configured to transmit power for operating the main shaft; an output unit disposed in parallel with the input unit and configured to operate the main shaft with the power from the input unit; and a transmission unit disposed in parallel with the input unit and the output unit so as to be capable of rectilinearly reciprocating between the input unit and the output unit and configured to transmit the power from the input unit to the output unit, wherein the main shaft is capable of operating in a high-speed mode, a low-speed mode, or a C-axis mode in accordance with the rectilinear reciprocation of the transmission unit.

A hydraulic type scissors gear removes factors that generate a backlash due to reduction of tension of existing springs by generating a relative motion between gears using oil pressure. The hydraulic type scissors gear includes: a first gear having an operation chamber and supplied with oil in the operation chamber; a second gear coaxially disposed on a side of the first gear to be rotate relative to the first gear; and a piston configured to rotate the second gear by applying force that pushes the second gear in a rotational direction opposite to a rotational direction of the first gear by being moved in the operation chamber by oil pressure supplied to the operation chamber.

A gear drive system is provided having a first gear and a second gear. The second gear has a first peripheral portion and a second peripheral portion. A first set of gear teeth can be defined peripherally over the first peripheral portion and/or the second peripheral portion. The first peripheral portion and/or the second peripheral portion can be more resilient, resulting in a first backlash between the first set of gear teeth and the teeth of the first gear, less than a second backlash between the second set of gear teeth and the teeth of the first gear. Each gear tooth of the second gear can have a gear tooth spacing between adjacent gear teeth. The gear tooth spacing over the first peripheral portion and/or the second peripheral portion can be less than the gear tooth spacing at portions other than the first peripheral portion and/or the second peripheral portion.