Classifications

• • G—PHYSICS
  • G04—HOROLOGY
  • G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
  • G04C13/00—Driving mechanisms for clocks by master-clocks
  • G04C13/08—Slave-clocks actuated intermittently
  • G04C13/10—Slave-clocks actuated intermittently by electromechanical step advancing mechanisms
  • G04C13/11—Slave-clocks actuated intermittently by electromechanical step advancing mechanisms with rotating armature
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K37/00—Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors
  • H02K37/10—Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors of permanent magnet type
  • H02K37/12—Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors of permanent magnet type with stationary armatures and rotating magnets
  • H02K37/14—Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors of permanent magnet type with stationary armatures and rotating magnets with magnets rotating within the armatures
  • H02K37/16—Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors of permanent magnet type with stationary armatures and rotating magnets with magnets rotating within the armatures having horseshoe armature cores

Definitions

• Quartz watches which include a stepping motor are equipped with an analog display whose motor is intended to drive the hands and possibly a date ring as well as, sometimes, an indicator of the days of the week.
• an analog display whose motor is intended to drive the hands and possibly a date ring as well as, sometimes, an indicator of the days of the week.
• it is therefore important that its motor advances exactly one step at each pulse it receives from the divider controlled by the quartz.
• it must overcome the resistances which are periodically offered to it by the accessory mechanisms (date ring, indicator of the days of the week) and not move, for example following shocks, during intervals between pulses.
• the magnetic couples which keep it at rest and which move it forward must for this purpose be strong enough.
• the electrical energy available in such a watch which is supplied by a miniature battery, is reduced.
• the watch engine must therefore work with the best possible performance.
• the pivoting of the motor rotor must be very free in order to avoid friction losses.
• the geometry of the rotor and stator poles must be very precise, since the slightest deviation immediately causes a significant drop in engine torque.
• Claim 1 defines a set of elements which are found individually in various known motors, but which, in combination, constitute a reliable motor for a quartz watch and whose component parts can, moreover, be connected in series without requiring subsequent adjustments.
• the single bearing of the rotor in fact, protects the motor from the defect of motors whose rotor is pivoted in two bearings while allowing a lower construction.
• Claim 2 ensures the mounting of the motor on the frame of the movement of the watch without disturbing the relative positions of the rotor and the stator of the motor.
• Fig. 1 is a plan view thereof
• Fig. 2 a diametral section.
• the motor shown comprises a shaft 1, which has come in one piece manufacture with a pinion 2,. formed at one of its extremi ⁇ ties.
• a ring 3 is driven onto the shaft 1. It carries the inner rolling path 4 of the balls 5 of a ball bearing, which constitutes the single bearing of the shaft 1 and therefore of the rotor 6 of the engine.
• the outer raceway 7 of the balls 5 is formed on a ring 8, which constitutes the fixed body of the bearing of the rotor 6.
• a washer 9, made of a material with high magnetic coercion power, is finally driven out on the end of the shaft 1 opposite the pinion 2. This washer 9 is magnetized diametrically, as indicated by the line in phantom lines in FIG. 1.
• the ring 8 is forcibly engaged in a bore 10 of the plate 11 of the movement of the watch. It carries a collar 12 which extends above the plate 11.
• a ferromagnetic bar 13 has an opening 14 through which it can be engaged with gentle friction, but without play, on the collar 12.
• This bar 13 constitutes the stator of the motor.
• the described engagement of the opening 14 on the flange 12 has the effect of perfectly centering the stator on the axis of the motor rotor.
• This stator is held axially in place on the plate 11 of the watch movement by the frame 15 of a coil 16, which receives the output pulses from the divider (not shown).
• a single fixing screw 17 of the armature 15 and the stator 13 on the plate 11 has been shown in the drawing, but it is quite clear that a second identical screw could be provided at the other end of the bar 13.
• the screw 17 is engaged in a threaded stud 18, mounted in the plate 11.
• a hole 19, of larger diameter than the stud 18, is drilled in the bar 13, so as to provide a rough centering of the stator relative to the rotor axis.
• Two diametrically opposite recesses 20 are formed in the bar 13, so that in the absence of excitation of the coil 16, the rotor 6 is oriented so that its magnetic axis takes the position presented by the dashed line in FIG. 1.
• the next pulse transmitted to the coil 16 will have the effect of producing a magnetization of the bar 13 such that a north pole will appear to the left of the rotor 6.
• This pulse will therefore rotate the rotor 6 by 135 ° in the direction of watch hands.
• the bar 13 is demagnetized.
• the rotor 6 therefore rotates another 45 ° in the same direction, until its magnetic axis has taken up the potion shown in phantom in FIG. 1, the south pole is this time at the top.
• the pinion 2 is engaged with a first mobile 21 of the gear train actuating this mechanism.

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Electromechanical Clocks (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4239160

Family Applications (1)

Country Status (3)

Families Citing this family (4)

Family Cites Families (13)

• 1982
  • 1982-04-26 WO PCT/CH1982/000058 patent/WO1982003928A1/en not_active Application Discontinuation
  • 1982-04-26 JP JP50128782A patent/JPS58501015A/ja active Pending
  • 1982-04-26 EP EP19820901108 patent/EP0077342A1/de not_active Withdrawn

Non-Patent Citations (1)

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