The invention relates to a display system for a timepiece, said system comprising a mobile arranged to be driven by a drive source by means of first teeth provided on the mobile. According to the invention, the mobile comprises at least second teeth including a teeth module of less than 0.05 mm, said second teeth being arranged so as to drive a display member either directly or indirectly.

The invention relates to a display system for a timepiece, said system comprising a mobile arranged to be driven by a drive source by means of first teeth provided on the mobile. According to the invention, the mobile comprises at least second teeth including a teeth module of less than 0.05 mm, said second teeth being arranged so as to drive a display member either directly or indirectly.

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 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.

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.

A pipe machining apparatus includes a frame, a tool support mounted on a tool carrier which is mounted on the frame, and a gearing arrangement for rotating the frame, and a motor for rotating the gearing arrangement. The gearing arrangement includes a toothed pinion gear, a toothed backlash adjustment gear which is moveable relative to the pinion gear and being capable of being fixed in position relative to the pinion gear by a locking assembly, and a toothed bull gear affixed to the tool carrier. The teeth of the bull gear are capable of being engaged with the teeth of the pinion gear and with the teeth of the backlash adjustment gear, the bull gear to minimize backlash.

A pipe machining apparatus includes a frame, a tool support mounted on a tool carrier which is mounted on the frame, and a gearing arrangement for rotating the frame, and a motor for rotating the gearing arrangement. The gearing arrangement includes a toothed pinion gear, a toothed backlash adjustment gear which is moveable relative to the pinion gear and being capable of being fixed in position relative to the pinion gear by a locking assembly, and a toothed bull gear affixed to the tool carrier. The teeth of the bull gear are capable of being engaged with the teeth of the pinion gear and with the teeth of the backlash adjustment gear, the bull gear to minimize backlash.

Provided is an elastically actuating device including an actuator configured to generate a rotary force, a gear part connected to the actuator and configured to transfer the rotary force from the actuator to an outside, and an elastic member including one end fastened to a ground and the other end connected to the gear part, and an elastic member including one end fastened to a ground and another end connected to the gear part, disposed outside the actuator to cover the actuator from the one end to the other end, and deformed in response to the gear part rotating relative to the actuator.

Provided is an elastically actuating device including an actuator configured to generate a rotary force, a gear part connected to the actuator and configured to transfer the rotary force from the actuator to an outside, and an elastic member including one end fastened to a ground and the other end connected to the gear part, and an elastic member including one end fastened to a ground and another end connected to the gear part, disposed outside the actuator to cover the actuator from the one end to the other end, and deformed in response to the gear part rotating relative to the actuator.

The invention relates to a device (4) for positioning meshing teeth (3, 8, 9) of a gear drive without any play, comprising a gear assembly (5), which gear assembly (5) comprises a main gear (6) having first teeth (8) and a gear (7) that is rotatable relative thereto in the circumferential direction having second teeth (9), and the main gear (6) comprises a hub part (10) on which the rotatable gear (7) is disposed, and a tolerance compensating element (12) comprising a shaft part (13) and a compensating part (14) is disposed radially underneath the main gear (6), and the compensating part (14) is connected to the shaft part (13) and to the hub part (10) of the main gear (6) so that the main gear (6) is connected exclusively via the compensating part (14) to the shaft part (13), and the compensating part (14) is made at least partially from a rubber elastic material.