JP2006230090A - Motor driving device and analog electronic clock - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify the construction of a motor driving device and make it possible to smooth the rotation of a motor. <P>SOLUTION: A control circuit 103 determines that the direction of rotation of the motor 105 due to vibration is positive in the cases where the detection signal Sr detected by a rotation detection circuit 106 is lower than a first reference level Vcomp1, within a first reference time after the motor 105 is rotationally driven by a normal driving pulse P1, and is lower than the first reference level Vcomp1 and higher than a second reference level Vcomp2 within a second reference time after the first reference time. Then, the control circuit rotationally drives the motor 105 with the same driving timing as the timing of driving by a corrected driving pulse P21, using an intermediate driving pulse P22 whose energy is larger than that of the normal driving pulse P1 and smaller than that of the corrected driving pulse P21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a motor driving device and an analog electronic timepiece in which a display hand is driven to rotate by the motor driving device.

Conventionally, an analog electronic timepiece has been used in which display hands such as an hour hand and a minute hand are driven to rotate by a motor driving device. The motor drive device includes a step motor that rotationally drives the display hand, and a control unit that rotationally drives the step motor.
The step motor includes a rotor housing through hole and a stator having a positioning portion that determines a stop position of the rotor, a rotor rotatably disposed in the rotor housing through hole, and a coil wound around the stator. And have. By alternately supplying drive pulses having different polarities from the drive circuit to the coils, magnetic fluxes having different polarities are alternately generated in the stator, thereby causing a step motor (in other words, a rotor) to be rotated at a predetermined degree by 180 degrees. The rotor is rotated in the direction (positive direction), and the rotor is stopped at a position corresponding to the positioning portion.

The rotational drive of the step motor requires power saving and certainty of the rotational drive. For this reason, in a normal state where the motor rotates normally, the rotor is rotated by a drive pulse of a predetermined energy (for example, a drive pulse having a predetermined width (normal drive pulse)). When the rotor does not rotate, it is driven so as to forcibly rotate by supplying a driving pulse (corrected driving pulse) having higher energy (for example, a wider pulse width) than the normal driving pulse (corrected driving method).
In the conventional correction driving method, when the detection signal (induced voltage) generated by the rotation of the rotor of the step motor is smaller than a predetermined level threshold voltage, the motor is determined to be non-rotating and a correction driving pulse is supplied. The motor is rotated. Thereby, while being able to save electric power, it is comprised so that the said rotor can be rotated reliably (refer patent document 1).

  However, when the rotor does not rotate 180 degrees, the detection signal falls below the threshold voltage and is driven with the correction drive pulse, and the rotor vibrates near the initial stationary position until just before the correction drive pulse is supplied. In addition, if the correction drive pulse is supplied when the rotor vibrates in the one direction, the rotational energy of the rotor becomes excessive, the rotor rotates more than 180 degrees, rotates 360 degrees, and the next It may rotate to the rest position. In this case, driving with the normal driving pulse or the correction driving pulse in the next cycle may cause the rotor to be sucked and cannot be rotated, resulting in a delay in moving the needle or unevenness in the moving operation. There is a problem that the hand movement operation is not constant and the display hand does not move smoothly.

  In order to solve this problem, a motor that detects that the rotation direction of the rotor due to vibration is a predetermined direction and rotates the rotor using a correction drive pulse that is narrower than the correction drive pulse. A drive device has been developed (see Patent Document 2). According to the invention described in Patent Document 2, since the rotor is rotated using a correction drive pulse with less energy, it is possible to prevent the drive energy from being excessive, and thus it is possible to prevent occurrence of a situation in which the rotor rotates 360 degrees. can do. In addition, power saving can be achieved.

  However, since the motor drive device supplies a narrow correction drive pulse when it is detected that the rotor is rotating in the one direction, the correction drive pulse is generated according to the generation timing of the detection signal. The supply timing fluctuates, and the rotor rotation timing fluctuates each time. Therefore, since the needle movement timing of the display needle is not constant, there is a problem that the needle movement of the display needle is not smooth and uneven movement of the needle occurs. In addition, since the drive timing varies, the circuit configuration becomes complicated and there is a problem that downsizing is difficult.

Japanese Patent Publication No. 61-15385 Paragraphs [0014] to [0024] of Japanese Patent Laid-Open No. 2004-45082, FIG. 1, FIG. 3, and FIG.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a motor driving device that can simplify the configuration and can smoothly rotate the motor.
Another object of the present invention is to provide an analog electronic timepiece capable of simplifying the configuration and smoothly moving the hands of the display hands.

  According to the present invention, the detecting means for detecting a detection signal generated at a level corresponding to the rotation of the motor, the driving means for rotationally driving the motor, and in the normal state, the driving means moves the motor in one direction by the normal driving pulse. And when the detection signal is smaller than the first reference level, it is determined that the motor has not rotated, and the motor is driven with a correction drive pulse having energy larger than that of the normal drive pulse. And a control unit configured to control the driving unit to forcibly rotate in the one direction. The control unit detects the detection signal detected after the rotation driving by the normal driving pulse. When less than one reference level, when the rotation direction of the motor due to vibration is in the one direction, the energy is higher than the normal drive pulse. The drive means is controlled to rotate the motor in the one direction at a timing that has a predetermined relationship with the drive timing of the correction drive pulse, using an intermediate drive pulse that has a large gap and energy that is smaller than the correction drive pulse. A motor driving device is provided.

  When the detection signal detected after the rotation drive by the normal drive pulse is smaller than the first reference level, the control means corrects the energy larger than the normal drive pulse when the rotation direction of the motor due to vibration is in one direction. The driving means is controlled so as to rotationally drive the motor in the one direction at a timing having a predetermined relationship with the driving timing by the correction driving pulse by using an intermediate driving pulse whose energy is smaller than that of the driving pulse.

  Here, the control means has a second reference time after which the detection signal is smaller than the first reference level within the first reference time after the rotational drive by the normal drive pulse and after the first reference time. In this case, when the level is lower than the first reference level and higher than the second reference level, it is determined that the rotation of the motor due to vibration is in the one direction, and the correction driving pulse is used using the intermediate driving pulse. The driving means may be controlled so as to drive the motor to rotate at a timing that is in a predetermined relationship with the driving timing.

Further, the control means may be configured to control the drive means using the intermediate drive pulse so as to rotationally drive the motor at the same timing as the drive timing by the correction drive pulse.
Further, the control means drives the motor to rotationally drive the motor using the correction driving pulse when the detection signal is smaller than the second reference level within the first reference time and the second reference time. You may comprise so that a means may be controlled.

In addition, according to the present invention, there is provided a step motor for rotationally driving the display hand, and a motor drive device that performs a time measuring operation based on a time signal serving as a time reference and controls the rotation of the step motor. In the analog electronic timepiece in which the time is displayed by the display hands by rotationally driving the step motor by the motor driving device, any one of the motor driving devices is used as the motor driving device. An analog electronic timepiece is provided.
The motor drive device rotationally drives display hands such as an hour hand by rotating the motor.

According to the motor driving device of the present invention, it is possible to smoothly rotate the motor. In addition, since the configuration can be simplified, it is possible to reduce the circuit scale when an integrated circuit is formed. Further, power saving can be achieved.
In addition, according to the analog electronic timepiece according to the invention, it is possible to smoothly move the display hands. In addition, since the configuration can be simplified, it is possible to reduce the circuit scale when an integrated circuit is formed. Further, power saving can be achieved.

Hereinafter, a motor driving device and an analog electronic timepiece according to an embodiment of the present invention will be described.
FIG. 1 is a block diagram showing a motor drive device according to an embodiment of the present invention and an analog electronic timepiece using the motor drive device. An example of an analog electronic wristwatch is shown as an analog electronic timepiece.

  In FIG. 1, an electronic timepiece includes an oscillation circuit 101 that outputs a reference clock signal of a predetermined frequency, a frequency divider circuit 102 that divides the output signal of the oscillation circuit 101 and outputs a time signal that serves as a reference for timekeeping operation, and a control circuit. 103, a drive circuit 104 as a drive means for rotationally driving the step motor 105 in response to a drive control signal from the control circuit 103, a rotation detection as a detection means for detecting a detection signal generated by the step motor 105 and the step motor 105 A circuit 106, a train wheel 107 that is rotationally driven by a step motor 105, and a display hand 108 such as an hour, minute, and second that is rotationally driven by the train wheel 107 are provided. The control circuit 103, the drive circuit 104, and the rotation detection circuit 106 constitute a motor drive device.

  The control circuit 103 is configured to perform various kinds of control including processing described later by an IC logic circuit (not shown). Alternatively, the control circuit 103 is constituted by a central processing unit (CPU) and a memory (both not shown), and a program stored in advance in the memory is executed by the CPU, whereby various processes such as those described later are performed. It is configured to perform control. The control circuit 103 constitutes a time measuring means for measuring time using the time signal from the frequency dividing circuit 102, a control means for controlling each component of the electronic timepiece and the whole, and the rotation of the step motor 105 together with the drive circuit 104. A rotation control means for controlling driving is configured.

FIG. 2 is a front view of the step motor 105 used in the analog electronic timepiece according to the embodiment of the present invention, and the configuration itself is a known step motor.
In FIG. 2, a step motor 105 includes a stator 201 made of a magnetic material, a coil 202 wound around the stator 201, and a two-pole rotor rotatably disposed in a through hole 204 provided in the stator 201. 203. The stator 201 is formed with saturable portions 205 and 206 and inner notches 207 and 208 for determining the stop position of the rotor 203.

  When a rectangular wave drive pulse is supplied between the terminals a and b of the coil 202 and a current i flows in the direction of the arrow in FIG. 2, a magnetic flux is generated in the stator 201 in the direction of the arrow. As a result, the saturable portions 205 and 206 are first saturated, and then the rotor 203 is moved in a predetermined direction (the arrow direction (positive direction) in FIG. ) To 180 degrees. Thereafter, by alternately supplying drive pulses having different polarities to both terminals a and b of the coil 202, the same operation is performed, and the rotor 502 rotates in the predetermined direction by a predetermined angle (180 degrees). To do.

FIG. 3 is a timing diagram for explaining the operation of the motor drive device and the analog electronic timepiece according to the embodiment of the present invention. FIG. 4 is a flowchart showing processing of the motor drive device and the analog electronic timepiece according to the embodiment of the present invention, and is a flowchart mainly showing processing of the control circuit 103.
Hereinafter, the operation of the motor driving device according to the present embodiment and the electronic timepiece using the motor driving device will be described in detail with reference to FIGS.

  First, the control circuit 103 performs a time measuring operation using the time signal from the frequency dividing circuit 102, and outputs a drive control signal for controlling the motor 105 to be rotationally driven by the normal drive pulse P1 to the drive circuit 104. (Step S401 in FIG. 4). Here, the normal driving pulse is not a driving pulse (for example, a correction driving pulse or a demagnetizing pulse) used for driving in an emergency, but for rotating the motor 105 at a normal time when the motor 105 performs a normal rotating operation. This is a drive pulse having a predetermined pulse width to be used.

  In response to the drive control signal from the control circuit 103, the drive circuit 104 outputs a normal drive pulse P1 shown in FIG. 3A to the motor 105 to drive the motor 105 to rotate. The rotor 203 of the motor 105 rotates in a predetermined direction (a positive direction that is an arrow direction in FIG. 2) by a predetermined angle (180 degrees in the present embodiment) by the normal drive pulse P1. The motor 105 rotationally drives the display hand 108 via the train wheel 107. Thereby, the time according to the time signal is displayed by the display hand 108 at any time.

On the other hand, at the first reference time DT from time t1 to time t2 after driving by the normal drive pulse P1, the rotation detection circuit 106 detects a detection signal Sr having a signal level corresponding to the rotation of the motor 105, and the control circuit 103 By comparing the detection signal Sr with the first reference signal level Vcomp1, it is determined whether the motor 105 has rotated (step S402).
In step S402, when the detection level of the detection signal Sr is equal to or higher than the first reference signal level Vcomp1, the control circuit 103 determines that the motor 105 has rotated, and drives the next cycle with the normal drive pulse P1.

In step S402, if the detection level of the detection signal Sr does not reach the first reference signal level Vcomp1, the control circuit 103 determines that the motor 105 has not rotated.
In this case, the control circuit 103 detects the detection signal Sr, the first reference signal level Vcomp1, and the first reference signal level Vcomp1 at the second reference time DT2 from the time t2 to the time t3 after the first reference time DT has elapsed. The rotation direction of the motor 105 due to vibration is determined by comparing the second reference level Vcomp2 with a low level (step S403).

First, in step S403, the control circuit 103 determines that the motor 105 has rotated when the detection signal Sr equal to or higher than the first reference signal level Vcomp1 is generated, and drives the next cycle with the normal drive pulse P1. Do.
In step S403, if the signal level of the detection signal Sr does not reach the first reference signal level Vcomp1 and is equal to or higher than the second reference signal level Vcomp2, the rotation direction of the motor 105 due to vibration is the one direction ( It is determined that the drive energy is excessive in the rotational drive by the correction drive pulse P21, and the energy is larger than the normal drive pulse P1 and smaller than the correction drive pulse P21 (in this embodiment, the pulse width). Is a timing that has a predetermined relationship with the drive timing (the timing at which the pulse generation time is fixed at time t3) using the intermediate drive pulse P22 (which is wider than the normal drive pulse P1 and narrower than the correction drive pulse P21). In this embodiment, the motor 105 is moved at the same timing). It is driven to rotate in direction (step S404). As a result, the motor 105 is rotated by a predetermined angle (180 degrees) in the one direction (positive direction) without being excessively rotated by the intermediate drive pulse P22.

  In step S403, if the signal level of the detection signal Sr does not reach the second reference signal level Vcomp2, the control circuit 103 determines that the vibration of the motor 105 is small and that the drive by the correction drive pulse P21 does not cause excessive energy. At time t3, the motor 105 is rotationally driven by the correction drive pulse P21 (step S405). As a result, the motor 105 is rotated by a predetermined angle (180 degrees) in the one direction (positive direction) without being excessively rotated by the correction drive pulse P21.

  In the above embodiment, the drive pulses P1, P21, and P22 are configured to have the same voltage and different pulse widths. However, since the drive energies are different from each other, the pulse widths are the same and the voltage values are the same. Various changes can be made, such as making the energy different by changing them. That is, it is only necessary that the magnitude of the energy of each drive pulse satisfies the relationship of normal drive pulse P1 <intermediate drive pulse P22 <correction drive pulse P21.

  As described above, the motor drive device according to the present embodiment includes the rotation detection circuit 106 that detects the detection signal Sr generated at a level corresponding to the rotation of the motor 105, the drive circuit 104 that rotationally drives the motor 105, In the normal state, the drive circuit 104 controls the motor 105 to rotate in one direction by the normal drive pulse P1, and determines that the motor 105 has not rotated when the detection signal Sr is smaller than the first reference level Vcomp1. And a control circuit 103 for controlling the drive circuit 104 to forcibly drive the motor 105 in the one direction with the correction drive pulse P21 having energy larger than that of the normal drive pulse P1. 103 indicates that the detection signal Sr detected after the rotational drive by the normal drive pulse P1 is the first reference level. If it is smaller than Vcomp1, when the rotational direction of the motor 105 due to vibration is in the one direction, the correction drive is performed using the intermediate drive pulse P22 that has a larger energy than the normal drive pulse P1 and a smaller energy than the correction drive pulse P21. The drive circuit 104 is configured to rotate the motor 105 in the one direction at a timing that has a predetermined relationship with the drive timing t3 by the pulse P21.

  Here, the control circuit 103 determines that the detection signal Sr is smaller than the first reference level Vcomp1 within the first reference time (time t1 ≦ t <time t2) after the rotation drive by the normal drive pulse P1, and the first reference time. In a second reference time later than that (time t2 ≦ t <time t3), the rotation of the motor 105 due to vibration does not reach the first reference level Vcomp1 and is higher than the second reference level Vcomp2. The drive circuit 104 is controlled to rotate the motor 105 at a timing having a predetermined relationship with the drive timing t3 based on the correction drive pulse P21 by using the intermediate drive pulse P22.

  Therefore, since the drive energy does not become excessive, the motor 105 can be made smooth. Further, since the intermediate drive pulse P22 is supplied at a fixed timing that has a predetermined relationship with the correction drive pulse P21, the configuration can be simplified, and the circuit scale when integrated into an integrated circuit can be reduced. Become. In addition, there is an effect that power saving can be achieved.

  Further, the analog electronic timepiece according to the embodiment of the present invention performs a time measuring operation based on a step motor 105 for rotationally driving the display hand 108 and a time signal serving as a time reference, and rotates the step motor 105. In an analog electronic timepiece having a time display with a display hand 108 by rotationally driving a step motor 105 by the motor drive device, the motor described above is used as the motor drive device. It is characterized by comprising a driving device.

  Therefore, it is possible to move the display needle 108 smoothly. In addition, since the configuration can be simplified, it is possible to reduce the circuit scale when an integrated circuit is formed, and miniaturization is possible. In addition, there is an effect that power saving can be achieved.

  The present invention can be applied to various motor drive devices having a configuration including a stator, a coil wound around the stator, and a rotor rotatably held in the stator. Further, it can be applied not only to an electronic wristwatch but also to various analog electronic timepieces such as an electronic table clock.

1 is a block diagram of an analog electronic timepiece according to an embodiment of the present invention. It is a block diagram of the step motor used by embodiment of this invention. FIG. 4 is a timing diagram of the analog electronic timepiece according to the embodiment of the invention. It is a flowchart which shows the process of the analog electronic timepiece which concerns on embodiment of this invention.

Explanation of symbols

101... Oscillation circuit 102. Rotation detection circuit 107 ... train wheel 108 ... display hand

Claims (5)

Detection means for detecting a detection signal generated at a level corresponding to the rotation of the motor, drive means for rotationally driving the motor, and in a normal state, the drive means rotationally drives the motor in one direction by a normal drive pulse. And when the detection signal is smaller than the first reference level, it is determined that the motor has not rotated, and the motor is forcibly forced by the correction drive pulse having a larger energy than the normal drive pulse. A motor drive device having control means for controlling the drive means so as to be rotationally driven,
When the detection signal detected after the rotational drive by the normal drive pulse is smaller than the first reference level, the control means has the normal drive pulse when the rotational direction of the motor by vibration is in the one direction. The drive means is configured to rotationally drive the motor in the one direction at a timing having a predetermined relationship with the drive timing by the correction drive pulse, using an intermediate drive pulse having a larger energy than that of the correction drive pulse. The motor drive device characterized by controlling.   The control means has the detection signal smaller than the first reference level within a first reference time after rotational driving by the normal drive pulse, and within a second reference time after the first reference time. When the level is smaller than the first reference level and larger than the second reference level, it is determined that the rotation of the motor due to vibration is in the one direction, and the driving timing based on the correction driving pulse is determined using the intermediate driving pulse. The motor driving apparatus according to claim 1, wherein the driving unit is controlled to rotate the motor at a timing having a predetermined relationship with the motor.   The said control means controls the said drive means so that the said motor may be rotationally driven at the same timing as the drive timing by the said correction drive pulse using the said intermediate drive pulse. Motor drive device.   The control means controls the drive means to rotationally drive the motor using the correction drive pulse when the detection signal is smaller than the second reference level within the first reference time and the second reference time. 4. The motor driving device according to claim 2, wherein the motor driving device is controlled. A step motor for rotationally driving the display hand, and a motor drive device that performs a time measuring operation based on a time signal serving as a time reference and controls the rotation of the step motor, and the step by the motor drive device. In an analog electronic timepiece that displays the time with the display hands by rotating the motor,
An analog electronic timepiece comprising the motor driving device according to any one of claims 1 to 4 as the motor driving device.

Images