JP2014095641A - Motor device, driving device for motor, and clock - Google Patents

Abstract

To stably start and stop a sweep motor.
When a start instruction is given, a control circuit 15 supplies alternating pulsed excitation currents I01 and I02 to a drive coil 13 via a drive circuit 14, and generates a pulsed alternating magnetic field in a stator 11. Occur. A drive torque is generated by the action of this alternating magnetic field and the magnet of the rotor 12, and the rotor 12 rotates. The control circuit 15 supplies the excitation currents I01 and I02 to the drive coil 13 at least a predetermined number of times Nmin or more, even when an instruction to stop in a short time after starting, and the excitation current I02. Is finally supplied and stopped, so that the rotational position of the rotor 12 at the time of stop is stabilized, and the next start-up is stabilized.
[Selection] Figure 1

Description

  The present invention relates to a motor device, a motor driving device and a driving method, and a timepiece using them.

  There are two types of timepieces, one that drives the hands stepwise and the other that sweeps the hands. When sweeping the pointer, a sweep motor having a large inertia and a smooth movement is used.

  Since the inertia of the sweep motor is large, even if the application of the drive pulse is stopped, the sweep motor does not stop immediately but has a characteristic that the rotor continues to rotate for a certain time (see Patent Document 1).

  For example, in a state where the sweep motor is stably driven by the first drive pulse current P1 and the second drive pulse current P2 as shown in FIG. 3, at a predetermined timing after applying the second drive pulse current P2. When the application is stopped, the rotor rotates a number of times based on its own inertial force, and then stops in the state shown in FIG.

  When the rotor is driven normally, the rotor rotates with a predetermined inertial force. Therefore, if the application and stop timing of application of the second drive pulse current P2 is constant in the normally driven state, the rotor always stops in the state shown in FIG.

  However, when driving is stopped in a state where the inertial force of the rotor has not reached a predetermined value, such as when a stop is instructed in a short time after the start of hand movement, for example, the second driving pulse current P2 is applied. Even if the application is stopped at a predetermined timing later, the state shown in FIG. 1 may not be obtained.

  In such a case, even if the initial pulse current P0 is applied to try to rotate the rotor again, the rotor does not stop at the correct position, so it cannot immediately rotate in synchronization with the drive pulse current. While the first drive pulse current P1 and the second drive pulse current P2 are continuously applied, the rotation is started in synchronization with the applied pulse.

  In this way, the sweep motor has a problem that the rotor stop position is not fixed, and this causes a problem that when it is instructed to start, it cannot immediately start rotating in synchronization with the drive pulse. In order to avoid such a problem, various drive controls for rotating the rotor in a predetermined direction are performed.

JP-A-11-2899796

  In recent electronic timepieces, control for temporarily stopping or restarting the hand movement is also performed for power saving and silent operation.

For this reason, there is a case where the start of the hand movement and the stop of the hand movement are instructed continuously. In such a case, the rotor may not be stopped at a normal position as described above. If the rotor has not stopped at the normal position, even if the next operation is instructed, the rotor cannot immediately rotate in synchronization with the drive pulse, so the time lag between the instruction operation timing and the start timing of the operation is large. Become. If this time lag becomes large, for example, even if the start of hand movement is instructed in accordance with the time signal, the start of the hand movement will be delayed, making it difficult to set the time of the clock.
Similar problems may occur with respect to driving other than the timepiece.

  The present invention has been made in view of the above circumstances, and even if a stop is instructed in a short time after the start, the motor device, the drive device, and the drive method that can be rotated immediately in synchronization with the drive current at the next start It is another object of the present invention to provide a watch using them.

In order to achieve the above object, a motor device according to a first aspect of the present invention includes:
A stator,
A rotor,
A coil wound around the stator;
Drive means for driving the rotor by generating torque in the rotor by supplying an alternating drive current to the coil and generating an alternating magnetic field in the stator in response to a start instruction and a stop instruction And comprising
In response to the start instruction, the drive means supplies a drive current to the coil a predetermined number of times or more regardless of the timing of the stop instruction.

  For example, the drive means stores the minimum number of times of supply Nmin, and the drive means counts the number N of times that the drive current is supplied to the coil, and the stop instruction is given when N <Nmin. However, the drive current is supplied to the coil at least Nmin times.

  For example, the driving means alternately supplies a driving current in a first direction of the coil and a second direction opposite thereto, and finally supplies the driving current in the second direction, and then supplies the driving current. To stop.

  For example, at the time of start-up, the driving means passes a current for position adjustment in a first direction whose energy is smaller than that of the driving current to the coil, and then the driving current in the second direction and the driving current in the first direction. Current is passed alternately.

For example, the drive current and the position adjustment current are composed of pulsed currents.
The rotor may include an inertia ring for imparting inertia to the rotor.

In order to achieve the above object, a timepiece according to the second aspect of the present invention includes:
The motor device described above, a second hand, and a transmission means for transmitting the rotational force of the rotor of the motor device to the second hand.

In order to achieve the above object, a motor drive device according to a third aspect of the present invention provides:
A drive device that drives a rotor by generating a magnetic field in a stator by supplying a drive current to a coil of a step motor to generate torque in the rotor,
In response to the start instruction, the drive current is supplied to the coil a predetermined number of times or more, regardless of the timing of the stop instruction.
It is characterized by that.

In order to achieve the above object, a motor driving method according to a fourth aspect of the present invention includes:
A driving method for driving a rotor by generating a magnetic field in a stator by supplying a driving current to a coil of a step motor to generate torque in the rotor,
In response to the start instruction, the drive current is supplied to the coil a predetermined number of times or more, regardless of the timing of the stop instruction.
It is characterized by that.

  According to the present invention, at the time of stopping, the position of the rotor is stably stopped at a fixed position. Therefore, the probability of starting normally is high at the next start.

It is a figure which shows the structure of the sweep motor which concerns on embodiment, and its drive circuit. (A)-(c) is a figure explaining the structure of the rotor of the sweep motor which concerns on embodiment. It is a wave form diagram of the drive current supplied to a drive coil. It is a top view which shows the state which incorporated the sweep motor in the movement. It is sectional drawing which shows the state which integrated the sweep motor in the movement. It is a flowchart of operation | movement of a control circuit.

  Hereinafter, a motor device, a motor driving device and a driving method according to embodiments of the present invention, and a timepiece using them will be described.

  As described in the background art section, with a conventional sweep motor, when it is stopped in a short time after startup, there may be a problem that the motor does not rotate normally when restarted. As a result of the inventor's verification, it has been found that this is one of the causes that the stop position of the rotor is not stable because the number of drive pulses applied at the time of hand movement is too small. Therefore, in this embodiment, control is performed so that the drive pulse is applied a predetermined number of times or more so that the stop position of the rotor is stabilized.

  As shown in FIG. 1, the motor device 1 according to the present embodiment includes a stator 11, a rotor 12, a drive coil 13, a drive circuit 14, and a control circuit 15. In the present embodiment, the clockwise rotation in FIG. 1 is forward rotation, and the left rotation is reverse rotation.

  The stator 11 constitutes a magnetic path of an alternating magnetic field applied to the rotor 12, and includes a rotor accommodation hole 11 a that accommodates the rotor 12. A pair of notches 11b are formed in the rotor housing hole 11a so as to face each other. The pair of notches 11b is formed at a position where a line connecting them intersects the direction of the alternating magnetic field flowing through the stator 11 at a predetermined angle (for example, 10 to 80 °).

  The rotor 12 is composed of a disk-shaped permanent magnet magnetized in two poles, and is housed in the rotor housing hole 11a of the stator 11 so as to be rotatable about the rotating shaft 12c. More specifically, as shown in FIGS. 2A to 2C, the rotor 12 is formed by laminating a magnet 121, an inertia ring 122, and a gear 123 coaxially, and is integrally formed around the rotation shaft 12 c. It is arranged to be rotatable. The magnet 121 is formed in a disc shape and is magnetized in two poles. The inertia ring 122 has a constant weight and is used for smooth rotation of the rotor 12. Thereby, the motor apparatus 1 functions as a sweep motor. The gear 123 transmits the rotation of the rotor 12 to the pointer through the train wheel.

  In the non-excited state, the rotor 12 normally stops in a state where the magnetic pole boundary line coincides with the line connecting the notches 11b by the detent torque generated by the action of the notches 11b. This position is defined as a detent position.

  The drive coil (excitation coil) 13 is wound around the stator 11 and is subjected to an alternating magnetic field according to a first excitation (drive) current I01 supplied alternately and a second excitation (drive) current I02 flowing in the opposite direction. Is generated.

  The drive circuit 14 is connected to one end and the other end of the drive coil 13, and according to the control of the control circuit 15, as shown in FIGS. 3A and 3B, the first excitation current I01 and the first excitation current I01. The second excitation current I02 flowing in the opposite direction to is alternately supplied to the drive coil 13.

  The first excitation current I01 includes an initial pulse (position adjustment pulse) current P0 having a narrow pulse width first, and then a first drive pulse current P1 having a constant period. The initial pulse current P0 has a narrower pulse width than the first drive pulse current P1, and by itself, it is not possible to generate a torque sufficient to completely rotate the rotor 12, but the rotor 12 is reversed by the generated torque. The pulse current has a function of moving to a position having a large potential energy. On the other hand, the first drive pulse current P1 is a pulse current that generates torque for rotating the rotor 12 alone. The second drive pulse current P2 has the same current value and pulse width as the first drive pulse current P1, and is 180 ° out of phase with the first drive pulse current P1.

  The control circuit 15 functions as a means for driving the motor together with the drive circuit 14, includes a start switch 15 a and a stop switch 15 b, and supplies a control signal to the drive circuit 14, thereby first exciting the drive coil 13. A current I01 and a second excitation current I02 are passed.

  The control circuit 15 stores the value (minimum drive pulse current number) Nmin in the internal memory. Even if the stop switch 15b is operated immediately after the start switch 15a is operated and the start (start of movement) is instructed, the control circuit 15 operates the drive pulse current. The drive circuit 14 is controlled so that P1 and P2 are combined and Nmin pulses or more are supplied to the drive coil 13.

  The minimum number of drive pulse currents Nmin is obtained by actually operating a watch incorporating the motor device 1 under various operating conditions, and by experimentally determining a stop value of rotation at a predetermined position when drive pulse application is stopped. Is done. The conditions include, for example, posture (normal posture and prone position), second hand shaft load (pointer weight, pointer direction, unbalance, etc.), drive voltage, and the like. The minimum drive pulse current number Nmin is preferably small, but may be set in consideration of a certain safety factor. Further, it may be obtained by logical calculation or the like.

  In addition, the control circuit 15 finally controls the drive circuit 14 so that the second drive pulse current P2 flows through the drive coil 13 at the time of stop.

  By these actions, the rotor 12 is stably stopped at a desired position every time.

  The motor device 1 having the above configuration is incorporated in the movement illustrated in FIG. As shown in FIGS. 4 and 5, the gear 123 of the rotor 12 meshes with the intermediate gear 21, and the rotation of the rotor 12 is transmitted to the second hand wheel 23 via the intermediate gears 21 and 22 to drive the second hand. To do. Further, the rotation of the second hand wheel 23 is transmitted to the minute hand wheel 24 to drive the minute hand, and the rotation of the minute hand wheel 24 is transmitted to the hour hand wheel 25 to drive the hour hand.

  Incidentally, the rotating shaft 12c of the rotor 12 is formed with parallel portions 12d and 123d, and the magnet 121 and the inertia ring 122 are respectively formed with small holes. When the magnet 121 is stacked on the rotary shaft 12c, the parallel portion 12d of the rotary shaft 12c and the parallel portion 121d of the small hole of the magnet 121 are in contact with each other, thereby determining the position of the magnet 121 in the rotational direction with respect to the rotary shaft 12c. At the same time, when the inertia ring 122 is stacked on the rotating shaft 12c, the parallel portion 123d and the parallel portion 122d of the oblong hole of the inertia ring 122 come into contact with each other, so that the position of the inertia ring 122 in the rotation direction with respect to the rotating shaft 12c is changed. It is determined. Therefore, the rotating shaft 12c, the magnet 121, and the inertia ring 122 are positioned in a fixed positional relationship in the rotation direction when they are stacked.

  A holding hole 400 is formed in the inertia ring 122. When the rotor 12 is assembled into the movement, the holding hole 400 is used to position and incorporate the holding hole 400 so as to be positioned in the rotational direction as shown in FIG. It is. This position is the detent position of the rotor 12 shown in FIG.

  In the present embodiment, the rotor 12 is magnetized after being incorporated into the movement. When magnetized, if the position of the rotor 12 is not the detent position, the rotor 12 tries to rotate toward the detent position. At that time, the rotor 12 rotates in the forward direction and the reverse direction. There is. Although not described in detail in this embodiment, due to the tooth profile, when the rotation continues in the reverse direction, the gear 123 of the rotor 12 and the intermediate gear 21 may be clogged, resulting in malfunction.

  In the present embodiment, the rotor 12 is prevented from rotating in the reverse direction by performing magnetization in a state where the rotor 12 is previously positioned at the detent position shown in FIG.

  Next, the operation of the motor device 1 having the above configuration and a timepiece incorporating the motor device 1 will be described with reference to the flowchart of FIG.

  When the start switch 15a of the control circuit 15 is operated, the control circuit 15 starts the hand movement process shown in FIG. 6, and first, as shown in FIG. 3A, the initial pulse (position adjustment) of the first excitation current I01 is performed. The driving circuit 14 is controlled so as to supply the current pulse P0 to the driving coil 13 (step S1). By this control, an initial pulse current P 0 with a small energy flows in the positive direction from the drive circuit 14 to the drive coil 13, and a positive magnetic field is generated in the stator 11. The generated magnetic field is applied to the magnet 121 of the rotor 12, and the rotor 12 rotates in the reverse direction in a range where the magnetic field does not rotate completely.

  Further, the control circuit 15 initializes the supplied drive pulse current number N stored in the internal memory to 0 (step S1).

  Subsequently, the control circuit 15 stops the application of the initial pulse current P0 and supplies the second drive pulse current P2 of the second excitation current I02 to the drive coil 13 as shown in FIG. The drive circuit 14 is controlled (step S2). By this control, the second drive pulse current P2 flows from the drive circuit 14 to the drive coil 13 in the reverse direction, a reverse magnetic field is generated in the stator 11 and applied to the magnet 121 of the rotor 12 to generate drive torque. To do. The rotor 12 rotated in the reverse rotation direction by the initial pulse current P0 is applied with a force rotating in the normal rotation direction to return to the detent position. By applying the second drive pulse current P2 for driving in the forward rotation direction in this state, the rotor 12 can be reliably rotated forward from the stationary state.

  This rotation is transmitted from the gear 123 to the second hand wheel 23 via the intermediate gears 21 and 22, and the second hand also rotates. However, the second hand moves smoothly due to the inertia of the inertia ring 122 and the like.

  In addition, the control circuit 15 increments the number N of supplied drive pulse currents stored in the internal memory by 1 (step S2).

  Subsequently, it is determined whether or not the hand movement is continuing (stop is not instructed) (step S3). If it is continuing (step S3; Yes), the first drive pulse of the first excitation current I01 is determined. The drive circuit 14 is controlled so as to supply the current P1 to the drive coil 13 (step S4). By this control, the first drive pulse current P1 in the positive direction flows from the drive circuit 14 to the drive coil 13, a magnetic field in the positive direction is generated in the stator 11, and is applied to the magnet 121 of the rotor 12 to generate drive torque. To do. As a result, the rotor 12 further rotates, and the pointer also rotates. Further, the control circuit 15 increments the supplied drive pulse current number N stored in the internal memory by 1 (step S4).

  Subsequently, it is determined whether or not the hand movement is continuing (stop is not instructed) (step S5). If it is continuing (step S5; Yes), the process returns to step S2 and the same operation is repeated. .

  On the other hand, when it is determined in step S5 that stop of the hand movement is instructed (step S5; No), the control circuit 15 supplies the drive coil 13 with the second drive pulse current P2 of the second excitation current I02. Thus, the drive circuit 14 is controlled (step S6). As a result, the rotor 12 further rotates, and the pointer also rotates. Further, the control circuit 15 increments the number N of supplied drive pulse currents stored in the internal memory by 1 (step S6).

  Further, after supplying the second drive pulse current P2 in step S6 and when it is determined in step S3 that stop of the hand movement is instructed (step S3; No), the control circuit 15 counts the total number of supplied drive pulse currents. It is determined whether N is equal to or greater than the minimum drive pulse current number Nmin stored in the internal memory (step S7).

  When it is determined that the total number N of supplied drive pulse currents is less than the minimum drive pulse current number Nmin (step S7; No), the total number N of supplied drive pulse currents is equal to or greater than the minimum drive pulse current number Nmin. The drive pulse currents P1 and P2 are continuously output until the determination is made (steps S8 and S9).

  Finally, when it is determined in step S7 that the total number N of supplied drive pulse currents is equal to or greater than the minimum drive pulse current number Nmin (step S7; Yes), the current hand movement process is terminated.

  According to such a hand movement method, at least Nmin drive pulse currents P1 and P2 are supplied to the drive coil 13 in one hand movement process, so the rotor 12 rotates with a designed inertial force. As a result, after the application of the predetermined drive pulse to the rotor 12 is completed, the rotor 12 stops after being rotated by a predetermined number of revolutions. In the present embodiment, the supplied final drive pulse current is the second drive pulse current P2, as shown in FIG. Accordingly, the rotor 12 rotates only once after the application of the second drive pulse is completed, and then always stops at the detent position shown in FIG. This is the initial position of the rotor 12 at the end of driving. Therefore, the problem that the motor device 1 does not immediately synchronize with the drive pulse at the next start-up is less likely to occur. Thereby, at least Nmin drive magnetic fields are applied to the rotor 12, and the rotor 12 stops at least (Nmin + 1) / 2 rotations.

  Thus, in this embodiment, even if the stop of the hand movement is instructed, the supply of the drive pulse is not stopped immediately, but is stopped after at least Nmin drive pulse currents P1 and P2 are supplied. The rotor 12 rotates with a predetermined inertial force. Therefore, if the hand movement is stopped after supplying this drive pulse current for Nmin, the rotor 12 stops after rotating a predetermined number of times, so the stop position of the rotor is stabilized. Therefore, the rotor 12 can start rotating immediately in synchronization with the drive pulse when the next movement is instructed.

  In the above embodiment, the start switch 15a and the stop switch 15b are arranged and the start and stop of the hand movement are instructed by the switch operation. However, the start and stop of the hand movement is indicated by another arbitrary signal. You may instruct. For example, an illuminance sensor, a posture sensor, and the like may be arranged, and the operation status of the timepiece may be determined from the output of these sensors to determine start / stop.

  Further, although the motor in which the rotor 12 is magnetized to two poles is illustrated, four or more poles may be used.

  In the above-described embodiment, an example in which the initial pulse current (position adjustment pulse current) is supplied has been described. However, this may not be provided.

  The inertia ring 122 may have other shapes or may not be provided.

  In addition, the above-described hardware configuration and flowchart are examples, and can be arbitrarily changed and modified.

  In addition, a computer program that causes a processor that functions as a control circuit to execute the above-described processing may be distributed via a recording medium or the like, supplied to the processor, and executed.

DESCRIPTION OF SYMBOLS 1 Motor apparatus 11 Stator 11a Rotor accommodation hole 11b Notch 12 Rotor 12c Rotating shaft 13 Drive coil 14 Drive circuit 15 Control circuit 15a Start switch 15b Stop switch 21, 22 Intermediate gear 23 Second hand wheel 24 Minute hand wheel 25 Hour hand wheel 121 Magnet 122 Inertial ring 123 Gear

Claims (9)

A stator,
A rotor,
A coil wound around the stator;
In response to a start instruction and a stop instruction, an AC drive current is supplied to the coil to generate an AC magnetic field in the stator, thereby generating torque in the rotor and driving the rotor. And comprising
In response to the start instruction, the drive means supplies a drive current to the coil a predetermined number of times or more, regardless of the timing of the stop instruction.
The motor apparatus characterized by the above-mentioned. The drive means stores a minimum supply number Nmin,
The drive means counts the number N of times the drive current is supplied to the coil, and supplies the drive current to the coil at least Nmin times even when the stop instruction is given at the stage of N <Nmin.
The motor device according to claim 1. The drive means alternately supplies a drive current in the first direction of the coil and a second direction opposite thereto, and finally supplies the drive current in the second direction, and then stops supplying the drive current. To
The motor device according to claim 1, wherein the motor device is a motor device. At the time of start-up, the driving means passes a current for position adjustment in a first direction having energy smaller than that of the driving current to the coil, and subsequently outputs a driving current in the second direction and a driving current in the first direction. Alternately
The motor device according to claim 1, 2, or 3. The drive current and the position adjustment current are composed of a pulse current.
The motor device according to claim 4. The rotor comprises an inertia ring for imparting inertia to the rotor;
The motor device according to claim 1, wherein the motor device is a motor device. A motor device according to any one of claims 1 to 6;
A second hand,
A transmission means for transmitting the rotational force of the rotor of the motor device to the second hand;
With a watch. A drive device that drives a rotor by generating a magnetic field in a stator by supplying a drive current to a coil of a step motor to generate torque in the rotor,
In response to the start instruction, the drive current is supplied to the coil a predetermined number of times or more, regardless of the timing of the stop instruction.
The motor drive device characterized by the above-mentioned. A driving method for driving a rotor by generating a magnetic field in a stator by supplying a driving current to a coil of a step motor to generate torque in the rotor,
In response to the start instruction, the drive current is supplied to the coil a predetermined number of times or more, regardless of the timing of the stop instruction.
The motor drive method characterized by the above-mentioned.

Images