JP2008278580A - Method and device for inspecting static frictional torque of motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for inspecting the static frictional torque of a motor which can directly observe and evaluate the static frictional torque of the motor. <P>SOLUTION: In a three-phase brushless motor, a specified current is applied to each phase, and a step of breaking the above current is performed so that rotating magnetic fields may be generated in order, and it is determined whether the above motor has reached an angle which accords with the above number of steps. Moreover, two detectors, which have marking and phase differences, can detect the rotational directions and count the amount of revolution from two signals different in phase. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and apparatus for measuring and inspecting a static friction torque of a motor.

  In recent years, motor-applied products such as recording / reproducing apparatuses have been applied to portable applications. For this reason, with the demand for miniaturization of the motor, the generated torque of the motor is also reduced, and the static friction torque at the time of starting the motor cannot be ignored. There is also a phenomenon in which the start-up time varies due to the assembly accuracy of the motor and the variation in torque generated by the magnetic saturation of the motor core. For this reason, depending on the motor, it is necessary to inspect the static friction torque of the motor at the time of startup.

  In the conventional static friction torque inspection method, the starting position of the rotor of the motor is adjusted at a certain minute rotation angle from the reference position, and the motor is started a plurality of times for each starting position of the rotor, The starting time from when the motor is started to when a predetermined speed is reached is measured by the measuring device.

  The configuration and operation will be described with reference to FIG. 6. Reference numeral 71 denotes a motor, which includes a stator 72, a rotor 74, and a rotating shaft 73. A rotary encoder 75 is connected to the rotating shaft 73 of the motor 71, and a measuring device 76 is further connected. The measuring device 76 sends an angle measurement signal to the computer 77 and receives a reset signal from the computer 77. The computer 77 sends an angle command signal to the adjusting device 78. Also, a speed command signal is sent to the motor control device 80. Reference numeral 79 denotes an external output device such as a printer.

  In the system configured as described above, the computer 77 first adjusts the rotor 74 to a predetermined starting position by sending an angle command signal to the adjusting device 78. Next, the motor 71 is rotated until it reaches a predetermined rotation speed by sending a speed command signal to the motor controller 80.

  The measuring device 76 measures the time (start-up time) from when the motor 71 is started to start outputting pulses from the rotary encoder 75 until the rotation speed of the motor 71 becomes constant and the pulse output interval becomes constant. . For such measurement, the activation position is adjusted, for example, every 15 ° from the reference position, and each activation time is measured. And the distribution of the starting time for each starting position is derived.

That is, as can be seen from the above-described configuration and operation, the conventional static friction torque inspection method indirectly inspects the magnitude of the static friction torque of the motor 71 based on the startup time.
JP 60-87681 A

  However, in the above-described conventional configuration, the magnitude of the static friction torque of the motor 71 is indirectly inspected based on the start time, and therefore, at which position the static friction torque is generated and how large it is. Can not be observed, and it has not been directly linked to the investigation of the cause of the failure. In addition, there is a problem in that it cannot be directly evaluated to what extent the countermeasure is taken even if the countermeasure for the defect is taken, and the countermeasure takes time.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a motor static friction torque inspection method and apparatus capable of directly observing and evaluating the motor static friction force.

  In order to solve the above-described conventional problems, a method for inspecting a static friction torque of a motor according to the present invention is a three-phase brushless motor having a rotor portion that rotates with respect to a stator portion, and a predetermined current is applied to U-phase and V-phase A step of cutting off the current, a step of passing a predetermined current through the W phase and the V phase, a step of cutting off the current, and a step of passing a predetermined current through the W phase and the U phase and cutting off the current Applying a predetermined current to the V-phase and the U-phase and cutting off the current; supplying a predetermined current to the V-phase and the W-phase; cutting off the current; Energizing a predetermined current and cutting off the current, so that a rotating magnetic field is sequentially generated in the motor, and when the series of steps is completed, the series of steps is repeated again in the same order as described above, The motor is Is obtained by said determining whether the reached angular that matches the number.

Further, the method for inspecting the static friction torque of the motor of the present invention includes a step of supplying a predetermined current to the U phase and cutting off the current in a three-phase brushless motor having a rotor portion rotating with respect to the stator portion; Applying a predetermined current to the phase and cutting off the current; and passing a predetermined current to the W phase and cutting off the current so that a rotating magnetic field is sequentially generated in the motor; When the above steps are completed, a series of steps is repeated again in the same order as described above, and it is determined whether the motor has reached an angle that matches the number of steps. The static friction torque inspection apparatus of the present invention is connected to a test motor having a rotor portion rotating with respect to a stator portion, and includes a power source means for generating a predetermined exciting current to be given to the motor, The switching means for sequentially switching the excitation current so that the motor rotates, the control means for controlling the switching of the order and timing so that the rotor part of the motor rotates at least once, and the rotational position of the rotor part of the motor And a rotor rotational position detecting means for detecting the above.

  Alternatively, the apparatus for inspecting static friction torque of the motor of the present invention is connected to a test motor having a rotor portion rotating with respect to a stator portion, and a power source means for generating a predetermined excitation current to be given to the motor, and the motor Switching means for sequentially switching the excitation current so as to rotate, control means for controlling switching of order and timing so that the rotor part of the motor rotates at least once, and detecting a rotational position of the rotor part of the motor Rotor rotation position detection means and rotor rotation amount determination means for determining whether the rotation amount of the rotor is a rotation amount corresponding to the number of switching performed by the control means are provided.

  Alternatively, the static friction torque inspection apparatus for a motor according to the present invention includes a spindle portion including a rotor portion and a bearing portion before being assembled to the motor, a cradle to which the bearing portion of the spindle portion is attached, and the cradle. A rotating means provided so as to freely rotate with respect to the rotating means, a connecting means fixed to the rotating means, and connected so that the rotor part and the rotating means of the spindle part rotate synchronously, and the rotation A multi-pole magnetized magnet fixed to the means; a stator wound with a coil that is opposed to the magnet and generates a rotating magnetic field that rotates the rotating means; and the wound around the stator. Power supply means for generating an excitation current to be applied to the coil, switching means for sequentially switching the excitation current so that the rotating means rotates, and an order so that the rotor of the motor rotates at least once. And control means for controlling the switching of the timing, in which characterized in that a rotor rotation position detecting means for detecting a rotational position of the rotor portion or the rotating means of the spindle unit.

  Alternatively, the static friction torque inspection apparatus for a motor according to the present invention includes a spindle portion including a rotor portion and a bearing portion before being assembled to the motor, a cradle to which the bearing portion of the spindle portion is attached, and the cradle. A rotating means provided so as to freely rotate with respect to the rotating means, a connecting means fixed to the rotating means, and connected so that the rotor part and the rotating means of the spindle part rotate synchronously, and the rotation A multi-pole magnetized magnet fixed to the means; a stator wound with a coil that is opposed to the magnet and generates a rotating magnetic field that rotates the rotating means; and the wound around the stator. Power supply means for generating an excitation current to be applied to the coil, switching means for sequentially switching the excitation current so that the rotating means rotates, and an order so that the rotor of the motor rotates at least once. Control means for controlling switching of imming; rotor rotation position detection means for detecting the rotation position of the rotor part of the spindle part or the rotation means; and the amount of rotation of the rotor part of the spindle part or the rotation means is the control means. And a rotor rotation amount determination means for determining whether the rotation amount corresponds to the number of switching performed in step (b).

  Alternatively, the present invention is characterized in that the inspection is started after the excitation current is once supplied in the same excitation pattern as the excitation pattern given first before the control means starts the inspection.

  Further, in the motor static friction torque inspection method, the exciting current applied to the motor by the power source means and the switching means is a rectangular wave.

  Alternatively, in the method for inspecting the static friction torque of the motor, the excitation current applied to the motor by the power source means and the switching means is a sine wave.

  Further, the power supply means is a current source for controlling the supply current, and the switching means includes a low impedance holding means for keeping the load of the power supply means at a small impedance in a state where the power supply means and the motor are not connected. It is characterized by.

  Alternatively, the power supply means is a current source that controls supply current, and the power supply means includes a power supply control means that instructs the power supply means not to flow current when the motor is not connected to the power supply means by the switching means. It is what.

  Furthermore, in the present invention, the rotor rotational position detecting means can detect two signals having a phase difference and a marking capable of detecting a signal more than twice the number of excitation patterns required for at least one rotation applied to the rotor. And the judging means counts the direction of rotation and the amount of rotation from the two detected signals having different phases.

  According to the method and apparatus for inspecting the static friction torque of the motor of the present invention, it is possible to surely capture a motor having a problem in which the static friction force varies greatly depending on the rotor rotational position.

  Embodiments of a method and apparatus for inspecting a motor's static friction torque according to the present invention will be described below in detail with reference to the drawings.

(Embodiment 1)
1 and 2 show a configuration diagram of a motor static friction torque inspection method and apparatus and a timing of energization between motor terminals according to the first embodiment of the present invention.

  The structure of this static friction torque inspection method and apparatus will be described with reference to FIGS. Reference numeral 7 denotes a motor to be measured. A rotor disk 8 is attached to the rotor portion of the motor 7 by screwing or a magnet clamp. The rotor disk 8 is provided with a reference position marking 9 for detecting the rotation reference position and an encoder marking 10 for detecting the position and speed. These markings may be provided directly on the rotor portion of the motor 7. A sensor 11 reads the encoder marking 10 to detect the position and speed, or reads the reference position marking 9 to detect the reference position. Reference numeral 3 denotes a switching means for driving the motor, and reference numeral 2 denotes a power supply means for supplying power to the switching means 3. Reference numeral 5 denotes rotor position detection means for reading a signal from a marking placed on the rotor disk 8 by a sensor, and reference numeral 6 denotes rotor rotation amount determination means for processing the signal from the rotor position detection means 5 to determine the rotor rotation amount. Reference numeral 1 denotes control means which controls the power supply means 2, switching means 3, and low impedance holding means 4 (described later) by signals from the rotor position detection means 5 and the rotor rotation amount detection means 6.

  In the configuration diagram of FIG. 1, the power supply means 2 operates so as to transmit a current output command 50 from the control means 1 to the power supply means 2 and to output an excitation current 51 corresponding thereto. The current output command 50 determines a unique numerical value for each model. Here, the power source means 2 is preferably a current source. Of course, the power supply means 2 may be a voltage source, a voltage output command may be given instead of the current output command 50, and an excitation current according to the impedance of the motor may be flowed. It was found that inspection accuracy can be improved because it can be managed accurately.

  The switching means 3 that receives the switching command 52 from the control means 1 is connected so that the exciting current 51 flows to the terminals (U, V, W) of the motor 7. The rotor or rotor disk 8 rotates and stops at a position where the magnetic balance between the rotating side and the stationary side in the motor 7 can be obtained by the excitation current 51 flowing in the motor 7.

  As shown in FIG. 2, the switching command 52 is transmitted to the switching means 3 by the control means 1 so that the rotor or the rotor disk 8 generates a rotating magnetic field and the rotor rotates accordingly. The command given to the switching means 3 rotates the motor at a relatively low speed like a stepping motor. Although there are various switching patterns for generating a rotating magnetic field, in FIG. 2, energization is performed in the order of (U−V) → (V−W) → (W−U). In addition, a pattern of (U−V) → (W−V) → (W−U) → (V−U) → (V−W) → (U−W) is also conceivable.

When such switching is performed, a timing at which the excitation current 51 does not flow to the motor 7 is provided. This is because, when energized with a certain excitation pattern, when the rotor moves from the current magnetic stable point to the next magnetic stable point, the rotor settles at that position, so it is attracted to the stable point. If the vibration is not sufficiently settled, the next excitation pattern must not be energized. This is because if the next excitation pattern is energized during settling vibration, the static friction force and the dynamic friction force cannot be distinguished, and the loss torque cannot be accurately evaluated. At this time, when the power supply means 2 is in a constant current source operation, since the exciting current 51 is zero, the power supply means 2 operates to supply the maximum current, and the output terminal voltage rises. Next, when the excitation current 51 is commanded, the resistance value when the motor 7 is connected to the power supply means 2 is usually a low impedance of about 0.1 to 100Ω, so that the excitation current 51 does not flow. As a result, the state changes to a state of flowing through the motor 7, so that an excessive surge-like excitation current 51 flows and is not a set current. In order to prevent this new problem, the low impedance holding means 14 is operated so that the load of the current means 2 always has a low impedance while the switching means 6 does not pass the exciting current 51 to the motor 7.
As a result, the exciting current 51 is supplied to the motor 7 so that there is no excessive surge current and the rotor or rotor disk 8 rotates once.

  On the other hand, an encoder marking 10 is installed on the rotor or the rotor disk 8, and two signals having a phase difference are obtained from the encoder marking 10 by the sensor 11, and these signals are counted by the rotor position detecting means 5. Thus, the rotor position and the rotor rotation direction can be grasped. Further, a reference position marking 9 is provided so that the reference position of the rotor or the rotor disk 8 can be grasped.

  It is desirable to set the number of pulses of the encoder marking 10 to be twice or more the number of positions per circumference where the rotor or rotor disk 8 is positioned by the excitation current 51. Thus, it can be accurately known whether the rotor or the rotor disk 8 has moved to the next stop position. In a case where the number of positions per one circumference where the rotor or rotor disk 8 is positioned is less than twice, the amount of position information detected by the sensor 11 is small, and the rotor or rotor disk 8 moves to the next stop position. There is a case where I don't even know. In that case, even if the rotor or the rotor disk 8 makes one turn, it is not detected that it makes one turn.

  The rotor rotation amount / direction counted by the rotor position detection means 5 is transmitted to the rotor rotation amount determination means 6. On the other hand, excitation rotation amount information 53 corresponding to the switching command 52 commanded from the control unit 1 to the switching unit 3 is transmitted to the rotor rotation amount determination unit 6. The counted rotor rotation amount / direction and the excitation rotation amount information 53 are compared, and it is determined whether or not the rotor has rotated according to the switching command 5. If the rotation amount corresponding to the switching command 52 is detected, it can be determined that the static friction torque of the inspection motor 7 is not more than a predetermined value and there is no problem. On the other hand, if the rotation amount corresponding to the switching command 52 is not detected, the inspection motor 7 has a portion where the static friction torque is large, and the torque generated by the excitation current 51 does not exceed that portion and is out of step. Can be determined.

  FIG. 2 shows energization timing for applying an excitation current to the motor terminal. At the timing of energization between the motor terminals, before starting the inspection, the U-V of the pattern to be excited first is energized in advance for the length of the ON time 15 or more at the time of inspection, and the rotor or rotor when starting the inspection The position of the disk 8 is set to the position of this first excitation pattern. Thus, the inspection can be started from a magnetically stable point, and the inspection accuracy can be increased. Next, energization is performed in the order of UV, VW, and WU so that the rotor or the rotor disk 8 rotates sequentially. Here, the ON time 15 that is the time during which each energization pattern is energized is constant, and the OFF time 16 that is the time during which all energization patterns are not energized is also constant.

In the above configuration, the excitation current 51 is set to the minimum level required for the motor 7 to start, and the ON time and OFF time that the rotor or the rotor disk 8 can sufficiently follow if the motor is normal are set. When the switching command 52 for rotating the rotor or rotor disk 8 once is instructed, the rotor or rotor disk 8 of the normal motor 7 rotates once. The rotor or rotor disk 8 of the motor 7 in a defective state that takes a long time to start, such as a large static frictional force with respect to the starting torque, does not reach one rotation, and from some rotation position to the next stop position I can't move.
As a result, it is possible to inspect and determine a motor having a problem that the static friction force varies greatly depending on the rotor rotation position without omission.

  In the first embodiment, when the load of the power supply means 2 is not connected, the low impedance holding means 4 is connected. However, instead of the low impedance holding means 4, the power supply means 2 has the maximum current. By reducing the current output command 50 to zero so that no operation is performed, the cost can be reduced and the reliability against failure can be improved.

  Further, when the switching means 3 of the first embodiment performs an amplifier operation so that the exciting current 51 supplied to the motor 7 is not a rectangular wave as shown in FIG. In addition to reducing the influence of inertia, it is possible to inspect and measure the motion followability of the rotor 7 at a substantially continuous rotational position.

  Further, the rotor rotation amount determination means 6 of the first embodiment is eliminated, and the rotor position detection means 5, the sensor 11, and the reference position marking 9 are arranged at one location of the rotor 17 as shown in FIG. 18, it is possible to use a simple and inexpensive device by visually confirming that the rotor 18 moves once, and by reducing the inertia by eliminating the load on the rotor, shorter ON and OFF times can be set. Inspection can be performed in a short time.

  Moreover, in FIG. 2 of this Embodiment 1, although demonstrated with the two-phase excitation pattern which excites 2 phases simultaneously like the three excitation patterns of UV, VW, and WU, (UV ) → (W−V) → (W−U) → (V−U) → (V−W) → (U−W) is also available. Further, a one-phase excitation pattern such as COM-U, COM-V, and COM-W may be used. Needless to say, any excitation pattern that rotates the rotor or the rotor disk 8 may be used.

  Further, although the signal having the two phase differences is used by the sensor 11 according to the first embodiment, it is needless to say that the rotation position information such as an absolute value encoder or a resolver can be used so that the movement amount and direction can be understood.

  Note that the sensor 11 that detects the state of the reference position marking 9 and the encoder marking 10 according to the first embodiment is for detecting an optical change in the reflection amount with a black and white pattern, optical change such as transmission / cutoff, unevenness, etc. This is a mechanism for detecting a mechanical change of the magnetic field or detecting a magnetic change of a magnetic pole or the like.

(Embodiment 2)
FIG. 5 shows a configuration diagram of a motor static friction torque inspection method and apparatus according to Embodiment 2 of the present invention. In FIG. 5, 21 is a control means, 22 is a power supply means, 60 is a power output command, 61 is an excitation current, 62 is a switching command, 23 is a switching means, 25 is a stator, and 26 is wound around the stator. , 27 is a rotor part, 28 is a bearing part, 29 is a spindle motor part in which the rotor part 27 and the bearing part 28 are assembled and the rotor part 27 rotates freely, and 30 is a receiver for holding and fixing the bearing part 28. The base 31 is a rotor magnet mounted on the rotor 27, 32 is a connecting means for connecting the rotating means 33 described later so that it can rotate in synchronization with the rotor 27, and 33 is a rotating means on which the connecting means 32 is mounted. , 34 is a bearing interposed between the rotating means 33 and the cradle 30 so that the rotating means 33 can freely rotate, and 35 is mounted on the rotating means 33 so as to be opposed to the stator 25 and is disposed on the rotor magnet 31. A magnet with an integral multiple of the pole number, 36 is a rotor position detecting means for knowing the rotational position of the rotor portion 27 (marking).

  The difference from the configuration of the first embodiment is that the sensor 11 for detecting the encoder marking 9, the rotor position detecting means 5, the rotor rotation amount determining means 6 and the low impedance holding means 4 are eliminated. Only the rotor position detection means (marking) 36 without the encoder marking 9 is replaced with the stator 25, the coil 26, the spindle motor unit 29, the cradle 30, the connection means 32, the rotation means 33, the bearing 34 and the magnet 35. The point of replacing with is different.

The power supply means 22 operates so as to transmit the power supply output command 60 from the control means 21 to the power supply means 22 and to output the excitation current 61 corresponding thereto. The switching unit 23 that has received the switching command 62 from the control unit 21 is connected so that the exciting current 61 flows to the terminal of the coil 26. The rotating means 33 rotates and stops at a position where the stator 25 and the magnet 35 are magnetically balanced by the exciting current 61 flowing in the coil 26. At this time, for example, if the connecting means 32 is made of a magnetic material and is opposed to the rotor magnet 31 through an appropriate gap, the connecting means 32 and the rotor magnet 31 are magnetically coupled in a non-contact manner, and the rotating means 33 and the rotor 27 are connected. Move synchronously. Even when there is no gap, since the coupling means 32 and the rotor magnet 31 are magnetically coupled, the rotation means 33 and the rotor 27 move in the same manner. Of course, the rotating means 33 and the rotor part 27 may be mechanically coupled by the connecting means 32 with the shaft centers aligned with high accuracy.
The coupling means 32 is made of a magnet having the same number of magnetic poles as the rotor magnet 31 of the rotor portion 27 or an uneven ferromagnetic material having the same number of magnetic poles. Of course, you may comprise with a magnetic material without an unevenness | corrugation.

The control means 21 switches so that the rotor portion 27 of the normal spindle motor portion 29 follows sufficiently and switches the excitation current 61 corresponding to the minimum torque required for starting to rotate the rotor portion 27 once. The command 62 is transmitted to the switching means 23. The rotor position detector 36 provided in the rotor unit 27 visually recognizes the rotor position and determines whether to make one rotation.
Of course, the rotor position detecting means 36 may be detected by a sensor.

  If it rotates normally once, it can be determined that it is a spindle motor part that has a minimum torque required for starting and is a static frictional force that does not hinder starting. It can be determined that there is a problem and the activation time does not fit within the standard, or that the activation does not occur. Normally, the static frictional force of the motor is generated in the bearing portion 28 and the spindle motor portion 29, so that it is possible to capture the finished motor product (see FIG. 3) in advance without assembling it. Assembly man-hour loss can be reduced.

  Further, when the power supply means 22 is in constant current operation, the current output command 60 is a command for setting the exciting current 61 to zero while at least the switching means 23 does not connect the power supply means 22 and the coil 26. Thereby, it is possible to prevent an excessive surge current from being generated when the excitation current 61 is supplied to the coil 26 again.

  Similarly to the first embodiment, by providing the marking, the sensor, the rotor position detecting means, and the rotor rotation amount determining means, it is possible to make the determination without visually counting and determining the rotor position.

  INDUSTRIAL APPLICABILITY The motor rotor frictional force inspection method and apparatus according to the present invention is useful as a measurement method for failure analysis such as not performing smooth rotation as an inspection of motor start-up failure, and in particular, the length of a bearing, etc. Suitable for inspection and analysis measurement of hydrodynamic bearing spindle motor with small dimensions.

Configuration diagram of motor rotor static frictional force inspection method and apparatus according to Embodiment 1 of the present invention Schematic diagram of energization timing between motor terminals of motor rotor static friction force inspection method and apparatus in Embodiment 1 of the present invention Spindle motor structure Installation explanatory diagram of rotor position detection means in Embodiment 1 of the present invention Configuration of Motor Rotor Static Friction Force Inspection Method and Apparatus in Embodiment 2 of the Present Invention Configuration diagram of conventional motor start-up time inspection method and apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control means 2 Power supply means 3 Switching means 4 Low impedance holding means 5 Rotor position detection means 6 Rotor rotation amount determination means 7 Motor 8 Rotor or rotor disk 9 Reference position marking 10 Encoder marking 11 Sensor 15 ON time 16 OFF time 17 Rotor part 18 Rotor position detection means (marking)
DESCRIPTION OF SYMBOLS 21 Control means 22 Power supply means 23 Switching means 25 Stator 26 Coil 27 Rotor part 28 Bearing part 29 Spindle motor part 30 Base 31 Rotor magnet 32 Connecting means 33 Rotating means 34 Bearing 35 Magnet 36 Rotor position detection means (marking)
50 Power supply output command 51 Excitation current 52 Switching command 53 Excitation rotation amount information 60 Power supply output command 61 Excitation current 62 Switching command

Claims (12)

In the three-phase brushless motor having a rotor portion that rotates with respect to the stator portion,
Applying a predetermined current to the U-phase and the V-phase, and cutting off the current;
Applying a predetermined current to the W-phase and shutting off the current;
Applying a predetermined current to the W-phase and shutting off the current;
Applying a predetermined current to the V-phase and the U-phase, and cutting off the current;
Applying a predetermined current to the V-phase and the W-phase, and cutting off the current;
Applying a predetermined current to the U-phase and the W-phase, and cutting off the current;
Is performed so that a rotating magnetic field is sequentially generated in the motor, and when the series of steps is completed,
A method for inspecting the static friction torque of the stator portion and the rotor portion, wherein a series of steps is repeated again in the same order as described above to determine whether the motor has reached an angle that matches the number of steps. In the three-phase brushless motor having a rotor portion that rotates with respect to the stator portion,
Applying a predetermined current to the U phase and cutting off the current;
Applying a predetermined current to the V phase and cutting off the current;
Applying a predetermined current to the W phase and cutting off the current;
Is performed so that a rotating magnetic field is sequentially generated in the motor, and when the series of steps is completed,
A method for inspecting the static friction torque of the stator portion and the rotor portion, wherein a series of steps is repeated again in the same order as described above to determine whether the motor has reached an angle that matches the number of steps. A test motor having a rotor portion rotating with respect to the stator portion is connected,
Power supply means for generating a predetermined excitation current to be applied to the motor;
Switching means for sequentially switching the excitation current so that the motor rotates;
Control means for controlling switching of order and timing so that the rotor portion of the motor rotates at least once;
An apparatus for inspecting static friction torque between a stator portion and a rotor portion of the motor, comprising: a rotor rotational position detecting means for detecting a rotational position of the rotor portion of the motor. A test motor having a rotor portion rotating with respect to the stator portion is connected,
Power supply means for generating a predetermined excitation current to be applied to the motor;
Switching means for sequentially switching the excitation current so that the motor rotates;
Control means for controlling switching of order and timing so that the rotor portion of the motor rotates at least once;
Rotor rotation position detection means for detecting the rotation position of the rotor portion of the motor;
A static friction torque inspection device for a stator portion of the motor and a rotor portion, comprising: a rotor rotation amount determination unit that determines whether the rotation amount of the rotor is a rotation amount corresponding to the number of switching performed by the control unit. A spindle part composed of a rotor part and a bearing part before being assembled to the motor;
A cradle to which the bearing portion of the spindle portion is attached;
A rotating means provided to freely rotate with respect to the cradle;
A connecting means fixed to the rotating means and connected so that the rotor part of the spindle part and the rotating means rotate synchronously;
A multipole magnetized magnet fixed to the rotating means;
A stator wound with a coil facing the magnet and generating a rotating magnetic field for rotating the rotating means;
Power supply means for generating an excitation current to be applied to the coil wound around the stator;
Switching means for sequentially switching the excitation current so that the rotating means rotates;
Control means for controlling switching of order and timing so that the rotor of the motor rotates at least once;
An apparatus for inspecting a static friction torque between a bearing part of the spindle part and the rotor part, comprising a rotor part of the spindle part or a rotor rotational position detecting means for detecting a rotational position of the rotating means. A spindle part composed of a rotor part and a bearing part before being assembled to the motor;
A cradle to which the bearing portion of the spindle portion is attached;
A rotating means provided to freely rotate with respect to the cradle;
A connecting means fixed to the rotating means and connected so that the rotor part of the spindle part and the rotating means rotate synchronously;
A multipole magnetized magnet fixed to the rotating means;
A stator wound with a coil facing the magnet and generating a rotating magnetic field for rotating the rotating means;
Power supply means for generating an excitation current to be applied to the coil wound around the stator;
Switching means for sequentially switching the excitation current so that the rotating means rotates;
Control means for controlling the switching of the order and timing so that the rotor of the motor rotates at least once;
A rotor rotational position detecting means for detecting a rotational position of the rotor part of the spindle part or the rotating means;
A rotor rotation amount determination means for determining whether the rotation amount of the rotor portion of the spindle portion or the rotation means is a rotation amount corresponding to the number of switching performed by the control means; Static friction torque inspection device.   3. The static friction between the stator portion and the rotor portion according to claim 1, wherein the inspection is started after an excitation current is once supplied with the same excitation pattern as the first applied excitation pattern before the inspection is started. Torque inspection method.   The static friction torque of the stator portion and the rotor portion of the motor or the spindle portion of the motor according to claim 3, wherein the exciting current applied to the motor by the power source means and the switching means is a rectangular wave. A static friction torque inspection device for a bearing portion and a rotor portion.   7. The static friction between the stator portion and the rotor portion of the motor or the bearing of the spindle portion according to claim 3, wherein the exciting current applied to the motor by the power source means and the switching means is a sine wave. And frictional torque inspection device for rotor and rotor. A low-impedance holding means for keeping the load of the power supply means at a small impedance in a state where the power supply means and a test motor are not connected by the switching means; A static friction torque inspection device for a stator portion and a rotor portion of the motor according to claim 3. The power supply means is a current source for controlling supply current, and includes power supply control means for instructing the power supply means not to flow current when the power supply means and a test motor are not connected by the switching means. The static friction torque inspection device for the stator portion and the rotor portion of the motor according to claim 3. The rotor rotational position detecting means comprises two detectors having a marking number and a phase difference capable of detecting a signal more than twice the number of excitation patterns required for at least one rotation applied to the rotor. 7. The rotor rotation position determination means counts the rotation direction and the rotation amount from two detected signals having different phases, and the stator portion and the rotor portion of the motor according to claim 4 and 6, respectively. Static friction torque inspection device.