Abstract: A balance for a horological movement includes rigid portions consisting of a hub defining the pivot axis of the balance, a felloe, four arms connecting the felloe to the hub, and including four slots for receiving and gripping in position an inertia-block, each slot being delimited by an arm and by an elastic arm including a first end integral with the arm, and a second distal end free in relation to the hub, to the arm, and to the felloe sector. The balance includes two pairs of inertia-blocks, each pair of inertia-blocks having different masses to ensure different adjusting powers, a first pair of inertia-blocks for a basic adjustment, and second pair of inertia-blocks for a precise adjustment.

Abstract: A balance wheel-spring system including a balance wheel that oscillates about a balance wheel shaft and a spring, one inner spiral of which is fixed to the balance wheel shaft or to a collet mounted integrally with the shaft and one outer spiral of which is fixed to a stud integral with a bridge. The balance wheel includes a hub, a rim, an arm connecting the hub to the rim, a front face which includes a countersink and a rear face, the arm including a housing receiving and retaining a flyweight, and the spring being mounted opposite the front face of the balance wheel. The flyweight is mounted on the arm on the rear face of the balance wheel, the distance between the bottom of the countersink of the front face of the balance wheel and the spring is a predetermined interval between 0.05 mm and 1.50 mm.

Abstract: A balance wheel-spring system including a balance wheel that oscillates about a balance wheel shaft and a spring, one inner spiral of which is fixed to the balance wheel shaft or to a collet mounted integrally with the shaft and one outer spiral of which is fixed to a stud integral with a bridge. The balance wheel includes a hub, a rim, an arm connecting the hub to the rim, a front face which includes a countersink and a rear face, the arm including a housing receiving and retaining a flyweight, and the spring being mounted opposite the front face of the balance wheel. The flyweight is mounted on the arm on the rear face of the balance wheel, the distance between the bottom of the countersink of the front face of the balance wheel and the spring is a predetermined interval between 0.05 mm and 1.50 mm.

Abstract: A method adjusting oscillation frequency of a sprung balance assembly formed at random from balance springs and balance wheels. A production mechanism is set to limit a sample standard deviation of a single batch of balance springs to a predetermined maximum value, and to limit a sample standard deviation of a single batch of balance wheels to a predetermined maximum value within a given unbalance tolerance. The mean of the balance population is classified according to the mean of the balance springs, to obtain a difference corresponding to a maximum inertia decrease value of the balances, between extreme gaussian distribution values of balances and of balance springs. A random balance spring sample is taken from the single batch of balance springs and a random balance from among the single batch of balances. The inertia of the balance is adjusted according to a torque value of the balance spring sample.

Abstract: A method of improving pivoting of a wheel set for a scientific instrument, including an arbor pivoting or oscillating about an axis, in which: static balancing of the wheel set is performed to bring the center of gravity onto the axis; a desired value is determined for resulting unbalance moment of the wheel set about the axis, corresponding to a predetermined divergence between a first principal longitudinal axis of inertia of the wheel set, and the axis; at a predetermined speed about the axis, the resulting unbalance moment is measured with regard to the axis; and an adjustment of the resulting unbalance moment is made within a given determined tolerance with regard to the desired value, and performed by machining both sides of a median plane including the two secondary axes of inertia of the wheel set.

Abstract: Balance with inertia adjustment for timepieces, including a hub defining the pivot axis of the balance, a rim, a web extending between a lower plane and an upper plane on either side of a median plane, the web including at least one arm connecting the rim to the hub, the arm including a housing configured to receive and hold in place at least one inertia block. According to the invention, the inertia block has a front face and a rear face and is integrated in the balance arm, so that the front face and rear face are substantially in the upper plane and the lower plane.

Abstract: A method of improving the pivoting of a wheel set for a scientific instrument, including an arbor pivoting or oscillating about a wheel set axis, is provided. A static balancing of this wheel set is performed to bring the center of gravity onto this axis. A desired value is determined for the resulting unbalance moment of this wheel set about this axis, corresponding to a predetermined desired divergence between a first principal longitudinal axis of inertia of this wheel set, and this axis. This wheel set is set in rotation at a predetermined speed about this wheel set axis, and the resulting unbalance moment is measured with regard to this axis. An adjustment is made to the value of the resulting unbalance moment of this wheel set about this axis within a given determined tolerance with regard to this desired value.

Abstract: Balance with inertia adjustment for timepieces, including a hub defining the pivot axis of the balance, a rim, a web extending between a lower plane and an upper plane on either side of a median plane, the web including at least one arm connecting the rim to the hub, the arm including a housing configured to receive and hold in place at least one inertia block. According to the invention, the inertia block has a front face and a rear face and is integrated in the balance arm, so that the front face and rear face are substantially in the upper plane and the lower plane.

Abstract: The invention relates to a system of assembling a member, made of a first material, in the aperture of a part made of a second material having no plastic domain, using an intermediate portion made of a third material, mounted between said member and said part, According to the invention, the intermediate portion is accommodated against a shoulder of the part and is laterally locked in a resilient manner by at least one resilient locking device of the part to secure together the unit comprising the member-intermediate portion-part. The invention concerns the field of timepieces.

Abstract: A method of improving pivoting of a wheel set for a scientific instrument, including an arbor pivoting or oscillating about a wheel set axis, the method including: static balancing of the wheel set to bring the center of gravity onto the axis; determining a desired value for the resulting unbalance moment of the wheel set about the axis, corresponding to a predetermined desired divergence between a first principal longitudinal axis of inertia of the wheel set, and the axis; setting the wheel set in rotation at a predetermined speed about the wheel set axis, the resulting unbalance moment is measured with regard to the axis; and adjusting a value of the resulting unbalance moment of the wheel set about the axis within a given determined tolerance with regard to the desired value.

Abstract: A balance set for a timepiece, with inertia adjustment for adjusting inertia and/or balancing and/or oscillation frequency of the balance, with a balance including an insert inserted into a recess of a felloe connected to a hub by a joining surface. The balance includes on the felloe thereof an elastic holding mechanism including two antagonistic elastic lips which, when stressed, allow insertion of the insert into the recess and which, when released, prevent removal of the insert from the recess. A sprung balance or a timepiece can incorporate such a balance.

Abstract: A method of improving pivoting of a wheel set for a scientific instrument, including an arbor pivoting or oscillating about an axis, in which: static balancing of the wheel set is performed to bring the center of gravity onto the axis; a desired value is determined for resulting unbalance moment of the wheel set about the axis, corresponding to a predetermined divergence between a first principal longitudinal axis of inertia of the wheel set, and the axis; at a predetermined speed about the axis, the resulting unbalance moment is measured with regard to the axis; and an adjustment of the resulting unbalance moment is made within a given determined tolerance with regard to the desired value, and performed by machining both sides of a median plane including the two secondary axes of inertia of the wheel set.

Abstract: The invention relates to a system of assembling a member, made of a first material, in the aperture of a part made of a second material having no usable plastic domain, using an intermediate portion (7, 27, 47, 67, 87) made of a third material, mounted between said member and said part. According to the invention, the part is accommodated against a first level (6) of the intermediate portion and is resiliently locked on a second level of the intermediate portion by the member in order to secure together the unit comprising the member—intermediate portion—part. The invention concerns the field of timepieces.

Abstract: The invention relates to a system of assembling a member, made of a first material, in the aperture of a part made of a second material having no plastic domain, using an intermediate portion made of a third material, mounted between said member and said part, According to the invention, the intermediate portion is accommodated against a shoulder of the part and is laterally locked in a resilient manner by at least one resilient locking device of the part to secure together the unit comprising the member-intermediate portion-part. The invention concerns the field of timepieces.

Abstract: The invention relates to a system of assembling a member, made of a first material, in the aperture of a part made of a second material having no usable plastic domain, using an intermediate portion (7, 27, 47, 67, 87) made of a third material, mounted between said member and said part. According to the invention, the part is accommodated against a first level (6) of the intermediate portion and is resiliently locked on a second level of the intermediate portion by the member in order to secure together the unit comprising the member-intermediate portion-part. The invention concerns the field of timepieces.

Abstract: A method adjusting oscillation frequency of a sprung balance assembly formed at random from balance springs and balance wheels. A production mechanism is set to limit a sample standard deviation of a single batch of balance springs to a predetermined maximum value, and to limit a sample standard deviation of a single batch of balance wheels to a predetermined maximum value within a given unbalance tolerance. The mean of the balance population is classified according to the mean of the balance springs, to obtain a difference corresponding to a maximum inertia decrease value of the balances, between extreme gaussian distribution values of balances and of balance springs. A random balance spring sample is taken from the single batch of balance springs and a random balance from among the single batch of balances. The inertia of the balance is adjusted according to a torque value of the balance spring sample.

Abstract: A balance set for a timepiece, with inertia adjustment for adjusting inertia and/or balancing and/or oscillation frequency of the balance, with a balance including an insert inserted into a recess of a felloe connected to a hub by a joining surface. The balance includes on the felloe thereof an elastic holding mechanism including two antagonistic elastic lips which, when stressed, allow insertion of the insert into the recess and which, when released, prevent removal of the insert from the recess. A sprung balance or a timepiece can incorporate such a balance.