JP6240955B2 - Motor control device and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a motor control device that controls energization of a coil provided in a motor, and an image forming apparatus including the motor control device.

  As this type of motor control device, for example, there is a configuration described in Patent Document 1 (hereinafter referred to as a conventional motor control device). A conventional motor control device includes a dedicated rotary encoder capable of outputting an A-phase pulse and a B-phase pulse having a phase difference of 90 ° from each other for speed detection. In the speed detection process, every time an edge of the A and B phase pulses is detected, speed calculation is performed from the A and B phase pulses using four types of pulse periods (number of edges). In the speed detection process, a detection speed that matches the current speed among a plurality of detection speeds calculated from the pulse period is set as a speed detection value.

JP 2010-145085 A

  By the way, a motor (typically, a brushless DC motor) is a P-phase (P is a natural number of 2 or more, typically 3) Hall element or Hall IC for detecting the magnetic pole position of the rotor. It is often equipped with. Therefore, if the speed control of the rotor can be performed with the synthesized pulse signal obtained by synthesizing the detection signal from the P-phase hall element or the like, the rotary encoder is eliminated from the conventional motor control device, and between the hall element and the speed control. A single interface can be integrated. Here, the synthetic pulse signal is a signal whose logic is inverted every time the logic of any of the output signals of the P-phase detector changes.

However, the synthesized pulse signal has a variation in the cycle of the synthesized pulse signal due to at least one of the variations described in (1) to (3) below, and the cycle of the synthesized pulse signal is the rotor. May not correlate correctly with the rotation angle.
(1) Variation in mounting position of each Hall element on the substrate (2) Variation in mounting position of the substrate itself (3) Variation in magnetization width of the rotor

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a motor control device capable of reducing elements of variation included in a composite pulse signal, and an image forming apparatus having the motor control device.

In order to achieve the above object, one aspect of the present invention is a motor control device comprising a motor including a mover and a plurality of coils, and a P phase (P is a natural number of 2 or more) provided in the motor. a detector, by driving the motor, and P phase detector each electric phase angle outputs a pulse signal to be different from each other, one of the logic of the output pulse signal of the detector of the P phase change Each time, a signal synthesis unit that generates a signal whose logic is inverted as a synthesized pulse signal, and an interval between two consecutive edges in the synthesized pulse signal generated by the signal synthesis unit are sequentially counted. A variation processing unit for obtaining a period of a pulse signal output from any of the P-phase detectors by adding a predetermined number of edge intervals counted by the counting unit and the counting unit; Based on the period obtained by the serial variation processing unit, a speed control unit for controlling the energization amount of the each of said plurality of coils, wherein the variation unit is a predetermined number counted from the most recent edge interval of the edge The period S0 is obtained by adding the intervals, and the period S- (j-1) is obtained by adding a predetermined number of edge intervals starting from the edge interval before j (j is a natural number of 2 or more) times. Thereafter, N periods S0, S-1,..., S- (N-1) are sequentially obtained and added, and the speed control unit adds the result S0 + S-1 + ... + S- (N-) in the variation processing unit. based on 1), that controls the power supply amount to each of said plurality of coils.

Further, according to a preferred embodiment of the motor control device, the variation processing unit has coefficients a ₀ , a ₋₁ ,... In the _N periods S ₀ , S ₋₁ ,. , A _{− (N−1)} (where a ₀ > a ₋₁ >...> A _{− (N−1)} ) are sequentially multiplied, and then a ₀ × S ₀ , a ₋₁ × S ₋₁ , .., A _{− (N−1)} × S _{− (N−1)} are added, and the speed control unit adds the result a ₀ × S ₀ + a ₋₁ × S ₋₁ ,. _{Based on-(N-1)} * S- _(N-1) , the energization amount to each of the plurality of coils is controlled.

Another form of the motor control device is a motor including a mover and a plurality of coils, and a P-phase (P is a natural number of 2 or more) detector provided in the motor, and driving the motor Therefore, every time the logic of either the P-phase detector that outputs pulse signals having different electrical phase angles or the output pulse signal of the P-phase detector changes, its own logic is inverted. A signal synthesizing unit that generates a signal as a synthesized pulse signal, a counting unit that sequentially counts an interval between two consecutive edges in the synthesized pulse signal generated by the signal synthesizing unit, and a counter that counts A predetermined number of edge intervals are added to obtain a cycle of a pulse signal output from one of the P-phase detectors. Based on the period, a speed control unit for controlling the energization amount of the each of said plurality of coils, wherein the counting unit, the spacing of two rising edges contiguous in composite pulse signal generated by said signal combining unit And the interval between two consecutive falling edges, and the variation processing unit adds the predetermined number of rising edge intervals counted by the counting unit to detect the P phase. The first period of the pulse signal output from one of the detectors is obtained, and further, a predetermined number of falling edge intervals counted by the counting unit are added to output from one of the P-phase detectors. after determining the second period of the pulse signal, the first period and by adding the second period, the speed control unit, the first cycle in the variation processor Based on the addition result of the second period, controlling the power supply amount to each of said plurality of coils.

  Each of the P-phase detectors is typically a Hall element or a rotary encoder.

  According to another aspect of the present invention, there is provided an image forming apparatus including the motor control device according to the preferred embodiment, and prints an image on a sheet. Here, N is different depending on the type of the sheet.

  According to the above, it is possible to provide a motor control device that can reduce the variation element included in the composite pulse signal, and an image forming apparatus including the motor control device.

It is a block diagram which shows the structure of the motor control apparatus which concerns on 1st embodiment. It is a figure which shows the outline | summary of the dispersion | variation process of 1st embodiment. It is a flowchart of the motor drive process of 1st embodiment. It is a flowchart of the dispersion | variation removal process of 1st embodiment. It is a block diagram which shows the structure of the motor control apparatus which concerns on 2nd embodiment. It is a flowchart of the dispersion | variation removal process of 2nd embodiment. It is a block diagram which shows the structure of the motor control apparatus which concerns on 3rd embodiment. It is a figure which shows the outline | summary of the dispersion | variation process of 3rd embodiment. It is a flowchart of the motor drive process of 3rd embodiment. It is a flowchart of the dispersion | variation removal process of 3rd embodiment. It is a block diagram which shows the structure of the motor control apparatus which concerns on 4th embodiment. It is a flowchart of the motor drive process of 4th embodiment. It is a flowchart of the dispersion | variation removal process of 4th embodiment. 1 is a diagram illustrating an overall configuration of an image forming apparatus according to an application example. It is a flowchart which shows the 1st example of a process of the motor control part of an application example. It is a flowchart which shows the 2nd example of a process of the motor control part of an application example.

<< first embodiment >>
Hereinafter, the motor control device according to the first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3B.

  In FIG. 1, the motor control device 1 includes a P-phase brushless DC motor 2, a motor drive unit 3, and a motor control unit 4. Here, P is a natural number of 2 or more, and in the present embodiment, the case where P = 3 will be mainly described.

  The three-phase brushless DC motor 2 includes a magnet 21 as a mover (more specifically, a rotor), a U-phase coil 22U, a V-phase coil 22V and a W-phase coil 22W constituting a stator, and a three-phase brushless DC motor 2 Detectors h1, h2, and h3 and a mounting substrate 23 are provided.

  The magnet 21 has, for example, a disk shape and is supported so as to be rotatable with respect to a bracket (not shown) via a bearing or the like. The magnet 21 is alternately magnetized with N and S poles in the circumferential direction. In the present embodiment, the magnet 21 has six pairs of N poles and S poles, that is, a total of twelve poles. More specifically, each pole is magnetized to have a magnetization width of 30 °, but the actual magnetization width varies.

  The coils 22U to 22W are fixedly arranged on a bracket (not shown) at a predetermined interval in the rotation direction of the magnet 21.

  The detectors h <b> 1 to h <b> 3 are typically Hall ICs, and are attached to a bracket (not shown) so as to be disposed immediately below the magnet 21 in a state of being mounted on the mounting substrate 23, for example. Each of the detectors h1 to h3 outputs pulse signals p1 to p3 representing the change in polarity of the magnetic field caused by the rotation of the magnet 21 as Hi and Lo. Here, in this embodiment, since the number of poles is twelve, each detector h1 to h3 outputs pulse signals p1 to p3 for six cycles per one rotation of the magnet 21. As shown in FIG. 2, if one cycle of each of the pulse signals p1 to p3 is defined as an electrical angle of 360 °, the pulse signals p2 and p3 are shifted by 120 ° and 240 ° electrical angles with respect to the pulse signal p1. Thus, the motor control device 1 is designed. However, actually, the mounting positions of the detectors h1 to h3 on the mounting board 23 and / or the mounting positions of the mounting board 23 on the brackets vary. Furthermore, as described above, since the magnetization width varies, the deviation of the electrical angles of the pulse signals p1 and p2, the deviation of the electrical angles of the pulse signals p2 and p3, and the deviation of the electrical angles of the pulse signals p3 and p1. Is not strictly 120 °.

  The motor driving unit 3 typically includes a signal processing unit 31, a coil driving unit 32, and a signal synthesis unit 33.

  Pulse signals p <b> 1 to p <b> 3 are input to the signal processing unit 31. The signal processing unit 31 detects the rotation angle of the magnet 21 from the input pulse signals p <b> 1 to p <b> 3 at a predetermined time interval, and passes the detected rotation angle to the coil driving unit 32. The signal processing unit 31 further passes the input pulse signals p <b> 1 to p <b> 3 as they are to the signal synthesis unit 33 for the variation removal process described later.

  The coil drive unit 32 includes a plurality of switching elements, and these switching elements are interposed between the external power supply circuit 5 and the coils 22U to 22W. The coil driving unit 32 switches the on / off state of the built-in switching element according to the rotation angle obtained from the signal processing unit 31, and thereby changes the direction of the current flowing through the coils 22U to 22W. Moreover, the coil drive part 32 adjusts the energization amount supplied to the coils 22U-22W from the power supply circuit 5 according to the energization amount obtained from the speed control part 43 mentioned later.

  Output pulse signals p <b> 1 to p <b> 3 of the signal processing unit 31 are input to the signal synthesis unit 33. Each time the logic of any of the input pulse signals p1 to p3 changes, the signal synthesizer 33 generates a signal whose logic is inverted and outputs it as a synthesized pulse signal q as shown in FIG. When there are six pairs of magnetic poles as in the present embodiment, a composite pulse signal q having eighteen cycles is output per one rotation of the magnet 21. As described above, since the electrical angle between the pulse signals p1 to p3 is not exactly 120 °, variation occurs in each cycle of the synthesized pulse signal q.

  The motor control unit 4 includes, for example, a cycle counting unit 41, a variation processing unit 42, and a speed control unit 43.

The cycle counting unit 41 sequentially counts intervals (that is, cycles) T between the rising edges of the input combined pulse signal q using a clock having a frequency sufficiently higher than that of the combined pulse signal q, and passes it to the variation processing unit 42. Hereinafter, the latest edge interval T is T ₀ , the edge interval T counted immediately before is T _−1, and the edge interval T counted twice before is T ₋₂ . Similarly, the edge interval T counted i times before is defined as T _-i . Here, i is a non-negative integer and is 0, 1,.

Next, an outline of variation removal by the variation processing unit 42 will be described. The variation processing unit 42 is configured to be able to hold the latest P edge intervals T ₀ , T ₋₁ ,... T _{− (P−1)} obtained from the cycle counting unit 41. Variation processing unit 42, each time the latest edge interval T ₀ from the cycle counting unit 41 is input, the latest edge interval T back from ₀ past P number of edge interval T _0, T _-1, ... T - ₍ Add _P-1) (see Table 1 below). In the case of P = 3, as illustrated in FIG. 2, an addition value of three consecutive edge intervals T ₀ , T ₋₁ , T ₋₂ is obtained. Next, the variation processing unit 42 obtains an average value obtained by dividing the obtained addition value by P as the variation-removed period S ₀ . When the edge interval T ₋₁ is input, the average value of the edge intervals T ₋₁ , T ₋₂ , T ₋₃ is used. When the edge interval T ₋₂ is input, the edge intervals T ₋₂ , T ₋₃ , T ₋ are input. The average value of ₄ is obtained as the cycles S ₋₁ and S _{−2 from which} variation has been removed. As described above, in this embodiment, every time the variation processing unit 42 receives the edge interval T ₀ of the composite pulse signal q, (T ₋₂ + T ₋₁ + T ₀ ) / P is set as the variation-removed cycle S _0. The obtained cycle S ₀ is passed to the speed control unit 43.

In the case of P = 2, as described in Table 1 above, the average of the most recent past two edges interval T ₀ back from the edge interval T _0, T _-1 is taken, if the P = 4 The average of the past four edge intervals T ₀ , T ₋₁ , T ₋₂ , T ₋₃ is taken backward from the latest edge interval T ₀ .

The speed control unit 43 sequentially receives the variation-removed period S ₀ from the variation processing unit 42. In addition to this, a rotational speed (unit: rps, for example) designated by a higher-level control unit (not shown) is also input. Speed control unit 43 obtains the current rotational speed of the motor 2 from the most recent period S _0. Then, the amount of current supplied from the power supply circuit 5 to the coil drive unit 32 (specifically, the duty ratio) is controlled so that the current rotation speed becomes the designated rotation speed.

<< Specific Processing Procedure of First Embodiment >>
Next, with reference to FIG. 3A and FIG. 3B, a specific processing procedure of the motor control unit 4 will be described by taking the case of P = 3 as an example.

  In FIG. 3A, the variation processing unit 42 executes Steps A01 to A05. The period calculation result is reset at A01, the held values of the built-in buffers B [0] to B [2] are cleared at A02, the built-in buffer counter C is initialized at A03, and the enable flag at A04 F is turned off, an edge to be detected is set at A05, and an interrupt is permitted. Here, the edge setting is to set whether to count between rising edges or falling edges of the composite pulse signal q. When the setting of various variables is completed by A01 to A05, the speed control unit 43 controls the coil driving unit 32 to start the rotation of the motor 2 (that is, the magnet 21) (step A06). In addition, the order of A01-A05 is not restricted above, You may change suitably.

After execution of A05, the process of FIG. 3B can be interrupted during the process of FIG. 3A. That is, after the rotation of the motor is started, the synthesized pulse signal q is started to be input from the signal synthesis unit 33 to the period counting unit 41. The cycle counting unit 41 starts counting the edge interval T ₀ set between A05 out of the rising edges and the falling edges, and passes it to the variation processing unit. Each time the variation processing unit 42 receives the edge interval T ₀ , the variation processing unit 42 generates an interrupt and performs the processing of FIG. 3B.

In FIG. 3B, the variation processing unit 42 stores the latest edge interval T ₀ obtained from the cycle counting unit 41 in the buffer B [C] (C is the current value of the buffer counter C) (step B01).

  Next, the variation processing unit 42 determines whether or not C <2 when F = 0 (that is, the permission flag F is off) (step B02).

If the determination is No, the variation processing unit 42 sets the permission flag F to 1 (that is, ON) (step B03), and further calculates (T ₋₂ + T ₋₁ + T ₀ ) / 3 to eliminate variation. Period S ₀ is obtained (step B04). This step B04 is not performed until the values of the edge intervals T ₀ , T ₋₁ , T ₋₂ are stored in the buffers B [0] to B [2] after the rotation of the motor 2 is started. Further, at the time of start-up or speed change (acceleration or deceleration) where the change in the rotation speed of the motor 2 is large, the variation of the rotation speed of the motor 2 is tracked without delay rather than the variation removal. Even if the values of the edge intervals T ₀ , T ₋₁ , and T ₋₂ are held in the buffers B [0] to B [2], the variation is removed until the rotation speed of the motor 2 reaches substantially constant. It is also a practical process to avoid it.

Conversely, if it is determined as Yes at B02, the variation processing unit 42, the latest edge interval T _0, it is used as a period S ₀ (step B05).

  After steps B04 and B05, the variation processing unit 42 changes the value of the buffer counter C to (C + 1)% 3 (step B06), and ends the process of FIG. 3B. Note that% B06 in FIG. 3B is an operator for calculating the remainder. The meaning of the operator% is the same in the second and subsequent embodiments.

Here, FIG. 3A is referred again. When the speed control unit 43 obtains the cycle S ₀ from the variation processing unit 42 after starting the rotation of the motor 2 (that is, after A06), the speed control unit 43 obtains the rotational speed V by dividing the predetermined coefficient α by the cycle S _0. (Step A07).

  Next, the speed control unit 43 compares the rotation speed (that is, the target value) Vm designated by the host control unit with the calculated rotation speed V (step A08).

  As a result of the comparison, if Vm = V, the speed control unit 43 maintains the duty ratio of the current supplied to each of the coils 22U to 22W in speed control by PWM (pulse width modulation) or the like (step A09). On the other hand, if Vm <V, the duty ratio is decreased (step A10), and if Vm> V, the duty ratio is increased (step A11).

  Next to A09 to A11, the speed control unit 43 determines whether or not to end the process of FIG. 3A (step A12), and returns to A07 if determined No.

  On the other hand, if the determination is Yes, the interrupt is prohibited (step A13), and the motor control unit 4 ends the process of FIG. 3A.

<< Effects of First Embodiment >>
As described above, in each cycle of the pulse signals p1 to p3, (1) variation in mounting position of the corresponding detectors h1 to h3 on the mounting board 23 and (2) mounting of the mounting board 23 itself to the bracket Variation due to position variation does not occur. However, in this embodiment, in order to unify the interface between the motor driving unit 3 and the motor control unit 4, the cycle of the composite pulse signal q varies due to (1) and (2). End up. In order to reduce the influence of the variation, in this embodiment, the variation processing unit 42 obtains the latest P edge intervals T ₀ ,..., T _{− (P−1} ) every time the latest edge interval T ₀ is obtained. ₎ Is added. In the example of FIG. 2, such an added value coincides with the cycle of the pulse signal p3, and therefore variations due to (1) and (2) do not substantially occur. Therefore, there is no variation caused by (1) and (2) in the period S ₀ obtained from this added value. Further, as illustrated in FIG. 2, the previous cycle S ₋₁ is obtained by adding the edge intervals T ₋₁ , T ₋₂ , and T ₋₃ , and the previous cycle S ₋₂ is the edge interval T ₋₂ , It is obtained from the added value of T- ₃ and T- ₄ . Since these added values also coincide with the periods of the pulse signals p2 and p1, variations caused by (1) and (2) do not occur in the periods S _-1 and S _-2 obtained from the respective values. As described above, according to the motor control device 1, the interface between the motor driving unit 3 and the motor control unit 4 can be unified, and the period S ₀ that does not substantially include the above-described variation element can be obtained. it can. Since the speed control unit 43 controls the rotation speed of the motor 2 based on such a cycle S ₀ , the rotation fluctuation of the motor 2 can be suppressed.

<< Appendix 1 >>
The detectors h1 to h3 may be Hall elements or rotary encoders instead of the Hall ICs. However, in the case of a Hall element, an analog signal is output, so it is necessary to convert it to a binary signal.

<< Appendix 2 >>
The magnetizing direction of the magnet 21 is not limited to the circumferential direction, and may be another known direction. Further, the number of poles is not limited to twelve poles, and other values may be used.

<< Appendix 3 >>
Regarding the speed control of the motor 2 by the speed control unit 43, the energization amounts of the coils 22U to 22W are controlled by PWM. However, the present invention is not limited to this, and speed control may be performed by applying PI (proportional integration), PID (proportional integration differentiation), and these.

<< Appendix 4 >>
In the above embodiment, the rotary motor 2 is exemplified. However, the present invention is not limited to this, and the motor 2 may be a linear type.

  Note that the supplementary notes 1 to 4 are similarly applied to the second and subsequent embodiments.

<< Second Embodiment >>
Next, with reference to FIGS. 4-5, the motor control apparatus which concerns on 2nd embodiment of this invention is explained in full detail.

  In FIG. 4, the motor control device 1 </ b> A is different from the motor control device 1 of FIG. 1 in that a variation processing unit 42 </ b> A is provided instead of the variation processing unit 42. Other than that, there is no difference between the motor control devices 1A and 1. Therefore, in FIG. 4, the same reference numerals are assigned to the components corresponding to the configuration shown in FIG. 1, and the descriptions thereof are omitted.

  In addition to (1) and (2) described in the first embodiment, there are (3) variations in the magnetization width of the magnet 21 as factors of variation in the composite pulse signal q. In the present embodiment, an object is to reduce the influence of variations caused by (3).

In order to solve this problem, the variation processing unit 42A includes a ring buffer including buffers B [0], B [1],... B [(P + N−2)]. In the buffers B [0], B [1],... B [(P + N−2)], the latest (P + N−1) edge intervals T ₀ , T ₋₁ ,. _{-(P + N-2)} is retained. Here, N is a predetermined natural number and is set as a denominator in step C04 described later. In response to the input of the latest edge interval T ₀ , the variation processing unit 42A traces the past P edge intervals T ₀ , T ₋₁ ,... T _{− (P−1)} from the latest edge interval T ₀ . The average value is obtained as a period S ₀ from which the variations (1) and (2) are removed. Furthermore, past P number of edge interval T _-1 back from the previous edge interval T _-1, T _-2, ... The average value of T _-P, (1), the period S removal of the dispersion of (2) _{Get as -1} . Similarly, the variation processing unit 42A traces back the previous P edge intervals T _{− (j−1)} , T _−j ,... T _{− (P + )} from the edge interval T _{− (j−1)} j times before. The average value of _j-2) is obtained as a period S- _{(j-1) from} which the variations of the above (1) and (2) are removed ₍ see Table 2 below). Here, j is 1, 2,... N. Further, if the period S- _(j-1) represents that the change in polarity of the magnetic field caused by the magnetic pole pair with the magnet 21 is detected by a certain detector, the period S _-j represents the magnetic field generated by the adjacent magnetic pole pair. The change in polarity is detected by the adjacent detector. Further, the variation processing unit 42A calculates the average value of S ₀ , S ₋₁ ,... S _{− (N−1)} as the cycle S _AVE0 after variation removal.

For example, in the case of P = 3 and N = 2, as shown in FIG. 2, from the edge intervals T ₀ , T ₋₁ , T ₋₂ and the edge intervals T ₋₁ , T ₋₂ , T ₋₃ , the period S ₀ and period S ₋₁ can be obtained. Thereafter, the average value of the periods S ₀ and S ₋₁ is calculated as the period S _AVE0 (= (S ₀ + S ₋₁ ) / 2). The variation processing unit 42 passes the average value S _AVE0 obtained in this way to the speed control unit 43.

  In the second embodiment, the case where P = 3 and N = 2 has been described with reference to the above table 2. However, when P and N are other values, the corresponding columns in the above table 2 are displayed. Please refer.

<< Specific Processing Procedure of Second Embodiment >>
Next, with reference to FIG. 5, the specific processing of the motor control unit 4 will be described by taking the case of P = 3 and N = 2 as an example. The basic motor driving process is the same as that described above with reference to FIG. 3A, and thus the description thereof is omitted here.

Each time the edge interval T ₀ is input from the period counting unit 41, the variation processing unit 42A interrupts the process of FIG. 3A and performs the process of FIG. In FIG. 5, the variation processing unit 42A stores the edge interval T ₀ obtained from the cycle counting unit 41 in the buffer B [C] (C is the current value of the buffer counter C) (step C01).

  Next, the variation processing unit 42 determines whether F = 0 and C <3 (step C02).

If determined No, the variation processing unit 42 sets the permission flag F to 1 (step C03), and further calculates the following formula (2) to obtain the average value S _AVE0 (step C04). In step C04, as in step B04 described above, after the rotation of the motor 2 is started, the edge intervals T ₀ , T ₋₁ , T ₋₂ , T ₋₃ are set in the buffers B [0] to B [3]. Not done until the value is stored.

Conversely, if it is determined Yes in step C02, the variation processing unit 42A, it is the latest edge interval T _0, used in the motor driving process (step B05).

  After steps C04 and C05, the variation processing unit 42 changes the value of the buffer counter C to (C + 1)% 4 (step C06), and ends the process of FIG.

<< Effects of Second Embodiment >>
As described above, the variation processing unit 42A extracts a plurality of periods (periods S ₀ , S _−1, etc.) of the pulse signals p1 to p3 from the combined pulse signal q to obtain an average value S _AVE0 . Here, the plurality of extracted periods represent changes in the polarity of the magnetic field caused by different magnetic pole pairs in the magnet 21. Therefore, by taking these averages, the variation in (3) is reduced. Since the rotation speed of the motor 2 is controlled by such an average value S _AVE0 , it is possible to suppress the rotation fluctuation of the motor 2.

Further, as is clear from the above, in the present embodiment, the variation processing unit 42A does not obtain a plurality of cycles from the same pulse signal (for example, the pulse signal p3). Rather, the variation processing unit 42A obtains a period (for example, period S ₀ , S _-1, etc.) that is close in time from each of a plurality of pulse signals (for example, pulse signals S2, S3, etc.). The average value S _AVE0 is calculated. Therefore, the variation processing unit 42A only needs to hold a relatively small number of cycles of the synthesized pulse signal q as compared with the case of obtaining a plurality of cycles from a single pulse signal. As a result, since the necessary number of edge intervals T ₀ are aligned at an early stage, it is possible to suppress a decrease in performance of the rotation control of the motor 2.

<First modification>
In the second embodiment, the average value S _AVE0 is a simple average, but is not limited _thereto, and may be a weighted average. More specifically, the variation processing unit 42A further _performs a weighted average value S _{AVE0 of} a ₀ × S ₀ , a ₋₁ × S ₋₁ ,... A _{− (N−1)} × S _{− (N−1).} Is calculated. Since the weight the most recent period S _0, coefficients _{a 0, a -1, ...,} a - (N-1) _{is, a 0> a -1> ...} > a - a _(N-1) . For example, when P = 3 and N = 2, it is necessary to set the coefficients a ₀ and a ₋₁ . _Assuming that a ₀ = 2 and a ₋₁ = 1, the weighted average value S _AVE0 is expressed by the following equation (3).

<< Third embodiment >>
Next, with reference to FIGS. 6-8B, the motor control apparatus which concerns on 3rd embodiment of this invention is explained in full detail.

  In FIG. 6, the motor control device 1B is different from the motor control device 1 of FIG. 1 in that it includes a cycle count unit 41B and a variation processing unit 42B instead of the cycle count unit 41 and the variation processing unit 42. To do. Other than that, there is no difference between the motor control devices 1B and 1. Therefore, in FIG. 6, the same reference numerals are assigned to the components corresponding to the configuration shown in FIG. In the present embodiment, the case of P = 3 will be described in order to simplify the description.

Period count section 41B, a composite pulse signal with a sufficiently high frequency clock than q, sequentially counts the edge intervals T _'0 of the composite pulse signal q. Here, the edge interval T ′ ₀ is the interval between two consecutive edges in the composite pulse signal q, and more specifically, the interval from the rising edge to the falling edge, or from the falling edge to the rising edge. Is the interval. The cycle counting unit 41B sequentially transfers the obtained edge interval T ′ ₀ to the variation processing unit 42B.

Next, an outline of variation removal by the variation processing unit 42B will be described with reference to FIG. The variation processing unit 42B has two buffer groups Ba and Bb. The buffer group Ba is composed of buffers Ba [0], Ba [1], Ba [2]. For example, the last three edge intervals Ta between falling edges in the synthesized pulse signal q, that is, the edge interval Ta. ₀ , Ta ₋₁ ,... Ta ₋₂ can be held. The buffer group Bb is composed of buffers Bb [0], Bb [1],... Bb [2]. For example, the edge interval Tb between rising edges in the composite pulse signal q is the nearest P, that is, the edges. The intervals Tb ₀ , Tb ₋₁ ,... Tb ₋₂ can be held. Variation processor 42B receives the latest edge interval T _'0 from the cycle counting unit 41, if it is at an odd number, by using the values held in the buffer group Ba, between the falling edge of the pulse signal p1~p3 The added value of the period S _0a , that is, the edge intervals T _0a , T _−1a , and T _−2a is calculated (see FIG. 7). On the other hand, if the received edge interval T ′ ₀ is an even number, the period S _0b between the rising edges of the pulse signals p1 to p3, that is, the edge intervals T _0b , T ₋ is used using the held value of the buffer group Bb. An added value of _1b and T _−2b is calculated (see FIG. 7). After that, the variation processing unit 42B obtains (S _0a + S _0b ) / 6 as the cycle S ₀ after variation removal.

<< Specific Processing Procedure of Third Embodiment >>
Next, a specific processing procedure of the motor control unit 4 will be described with reference to FIGS. 8A and 8B.

  First, in FIG. 8A, the variation processing unit 42B executes Steps D01 to D05. The period calculation result is reset at D01, the held values of the buffers Ba [0] to Ba [2] and Bb [0] to Bb [2] of both systems are cleared at D02, and the built-in distribution counter D is reset at D03. Is initialized. In D04, the permission flag F is turned off. At D05, both edges are set as used edges and interrupts are permitted. When the setting of various variables is completed in steps D01 to D05, the speed control unit 43 starts the rotation of the motor 2 (step D06). Note that the order of D01 to D05 may be changed as appropriate.

After executing D05, the variation processor 42B, each time from the period counting unit 41B edge interval T _'0 is input, interrupt the processing of FIG. 8A, it performs the processing in FIG. 8B. In FIG. 8B, the variation processing unit 42B calculates the indexers Ca and Cb represented by the following expressions (4) and (5) (step E01).
Ca = ((D + 1)% 6) / 2 (4)
Cb = (D% 6) / 2 (5)
Here, D is the current value of the distribution counter D. The value of the counter D is incremented by 1 every time the edge interval T ′ ₀ arrives at the variation processing unit 42B in step E13 described later. The operator% indicates the calculation of the remainder. Note that although the division operator / is used in the expressions (4) and (5), these are integer operations, and the part after the decimal point is rounded down.

  Here, Table 3 below shows the calculation results of the indexers Ca and Cb with respect to the value D of the distribution counter.

As can be seen from Table 3 above, the values of the indexers Ca and Cb are incremented by 1 each time one period of the composite pulse signal q (that is, T ′ ₀ × 2) is counted, and 0 → 1 It is common in that it circulates → 2 → 0 →…. However, the value of the indexer Ca is incremented by 1 with a delay of a half cycle with respect to the value of the indexer Cb.

  Next, the variation processing unit 42 determines whether or not the current value of the distribution counter D is an even number (step E02).

When it is determined Yes, the variation processing unit 42 executes the first half of the variation removal processing using the buffer group Bb (step E03). More specifically, the period S _0b is obtained from the following equation (6).
S _0b = Bb [0] + Bb [1] + Bb [2] (6)

Next, the variation processing unit 42B adds the latest value of the edge interval T ′ ₀ to the held value of the buffer Ba [Ca] (Ca is the current value of the indexer Ca). Variation processor 42B further buffer Bb [Cb], overwriting the value of the latest edge interval T _'0 (step E04).

Next, the variation processing unit 42B executes the second half of the variation removal processing (step E05). More specifically, the held values of the buffers Ba [0] to Ba [2] are added to S _0b obtained by the previous equation (6) (see the following equation (7)).
_S0a + _S0b = _S0b + Ba [0] + Ba [1] + Ba [2] (7)

Here, in this embodiment, the variation removal process is divided into the first half (step E03) and the second half (step E05), and at step E04 between these, predetermined buffers Ba [Ca], Bb [Cb ] Has been updated. As described above, the variation removal process is divided into the first half and the second half. If step E04 is executed before steps E03 and E05, the buffer Bb [Cb] is overwritten with the latest edge interval T ′ ₀ . This is because a necessary value is deleted. In order to prevent this, step E03 is executed prior to step E04, and the period S _0b is obtained and saved before the buffer Bb [Cb] is overwritten. In contrast, the step E05, it is necessary to add the latest edge interval T _'0 to the buffer Ba [Ca], is executed after the step E04. Hereinafter, specific processing in the case of D = 6 will be described.

When D is 6, to obtain S _0a + S _0b , it is necessary to add what is input as the latest edge interval T ′ ₀ at the timing of the colored portion in Table 3. Here, for example, the buffer Bb [0] holds the added value of the two edge intervals T ′ ₀ obtained at the timing of D = 0, 1. The other buffer Bb [1] has an addition value of two edge intervals T ′ ₀ obtained when D is 2 or 3, and the other buffer Bb [2] has an addition value when D is 4 or 5. The added value of the two edge intervals T ′ ₀ is held. In this way, the buffer group Bb holds the total value of the edge intervals T ′ ₀ obtained when D is 0 to 5, and similarly, the buffer group Ba is obtained when D is 1 to 6. The total value of the obtained edge intervals T ′ ₀ is held. In steps E03 to E05, the total value of the holding values of the buffer groups Ba and Bb is calculated.

Here, when D is 6, if the latest edge interval T ′ ₀ is substituted into the buffer Bb [0], the stored value of the buffer Bb [0] written when D is 0 or 1 is lost. Resulting in. Therefore, when D is 6, the added value S _0b is calculated before substituting the edge interval T′0 into the buffer Bb [0], and the buffer Bb [0] written when D is 0 or 1 is calculated. ] Must be saved. When D is 0, what should be saved is the holding value of the buffer Bb [0], but if the holding values of the buffers Bb [1] and Bb [2] are saved, D is 8 or 10 In some cases, the variation removal process need not be divided into the first half and the second half.

On the other hand, with respect to Ba [0], when D is 6, only the value for the half cycle overwritten when D is 5 is held, so the latest edge interval T ′ ₀ must be added. Therefore, it does not become a value for one cycle of the synthesized pulse signal q. Therefore, after adding the latest edge interval T ′ ₀ in step E04, the second half of the variation removal processing is executed in step E05.

In the case of No in step E02, the variation processing unit 42 uses the buffer group Ba to obtain the period S _0a from the first half of the variation removal processing, that is, the following equation (8) (step E06).
S _0a = Ba [0] + Ba [1] + Ba [2] (8)

Next, the variation processing unit 42B adds the latest value of the edge interval T ′ ₀ to the held value of the buffer Bb [Cb] (Cb is the current value of the indexer Cb), and further adds the value to the buffer Ba [Ca]. The value of the latest edge interval T ′ ₀ is overwritten (step E07).

Next, the variation processor 42B as the second half of the variation removing process, the S _0a obtained in Equation (8), adds the value held in the buffer Bb [0] ~Bb [2] ( step E08, the following equation (See (9)).
S _0a + S _0b = S _0a + Bb [0] + Bb [1] + Bb [2] (9)

  Next, the variation processing unit 42B determines whether F = 0 (that is, the permission flag F is off) and D <6 (step E09).

If the determination is No, the variation processing unit 42B sets the permission flag F to 1 (that is, ON) (step E10), and further performs variation removal, that is, performs (S _0a + S _0b ) / 6 to eliminate variation. A completed cycle S ₀ is obtained (step E11).

On the other hand, when it is determined Yes in step E09, the variation processing unit 42B obtains the cycle S ₀ using the latest edge interval T ′ ₀ × 2 (step E12).

  After steps E11 and E12, the variation processing unit 42 increments the distribution counter D by 1 (step E13), and ends the process of FIG. 8B.

  Here, referring to FIG. 8A again. In FIG. 8A, the processing after step D7 is the same as the processing at step A07 in FIG.

<< Effects of Third Embodiment >>
As described above, according to the present embodiment, as illustrated in FIG. 7, the period S _0a represents one period of the pulse signal p2, and the period S _0b represents one period of the pulse signal p3. From the periods S _0a and S _0b , the variations of the above (1) and (2) are removed as described in the first embodiment. The period S ₀ is calculated from a plurality of periods (periods S ₀ , S _−1, etc.) of the pulse signals p1 to p3. Here, the plurality of extracted periods represent changes in the polarity of the magnetic field caused by different magnetic pole pairs in the magnet 21. Therefore, by taking these averages, the variation in (3) is reduced.

In the present embodiment, as shown in FIG. 7, the period S ₀ can be calculated if seven edge intervals T ′ ₀ are obtained. Therefore, the response of the motor 2 is compared with the second embodiment. Alternatively, servo characteristics can be improved. In the second embodiment, the edge interval T ₀ to the edge interval T ₋₃ of the composite pulse signal q, that is, the edge interval T ′ ₀ for eight times is required.

<< 4th embodiment >>
Next, with reference to FIGS. 9-10B, the motor control apparatus which concerns on 4th embodiment of this invention is explained in full detail.

  9, the motor control device 1C is different from the motor control device 1 of FIG. 1 in that it includes a cycle count unit 41C and a variation processing unit 42C instead of the cycle count unit 41 and the variation processing unit 42. To do. Other than that, there is no difference between the motor control devices 1C, 1. Therefore, in FIG. 9, the same reference numerals are assigned to the components corresponding to the configuration shown in FIG. 1, and the description thereof is omitted. In the present embodiment, the case where P = 3 will be described.

Period count unit 41C, like the cycle counting unit 41B, the edge interval T _'0 of a composite pulse signal q sequentially counts, and passes to the variation processor 42C.

Next, an outline of variation removal processing by the variation processing unit 42C will be described. The variation processing unit 42 </ b> C is configured to be able to hold the latest seven edge intervals T ′ ₀ , T ′ ₋₁ ,... T ′ ₋₆ obtained from the cycle counting unit 41. Each time the latest edge interval T ′ ₀ is input from the period counting unit 41C, the variation processing unit 42C traces back from the latest edge interval T ′ ₀ to the last seven edge intervals T ′ ₀ , T ′ _−1. ,..., T ′ ₋₆ are substituted into the following equation (10) to obtain the variation-removed cycle S ₀ .

S ₀ = {T ₀ + 2 × (T ₋₂ + T ₋₃ + T ₋₄ + T ₋₅ + T ₋₆ ) + T ₋₁ } / 6 (10)

<< Specific Processing Procedure of Fourth Embodiment >>
Next, a specific processing procedure of the variation processing unit 42C will be described with reference to FIGS. 10A and 10B.

  First, in FIG. 10A, the variation processing unit 42C executes Steps F01 to F05. In F01, the cycle calculation result is reset, in F02, the held values of the buffers B [0] to B [6] are cleared, and in F03, the buffer counter C is initialized. In F04, the permission flag F is turned off. In F05, both edges are set as used edges and interrupts are permitted. When the setting of various variables is completed in steps F01 to F05, the speed control unit 43 starts the rotation of the motor 2 (step F06). Note that the order of F01 to F05 may be changed as appropriate.

After execution of the F05, the variation processor 42C, each time from the period counting unit 41C edge interval T _'0 is input, interrupt the processing of FIG. 10A, it performs the process of FIG 10B. In FIG. 10B, the variation processor 42C, the buffer B [C] (C is the current value of the buffer counter C) stores the latest edge interval T _'0 obtained from the cycle counting unit 41C (Step G01) .

  Next, the variation processing unit 42C determines whether F = 0 (that is, the permission flag F is off) and C <6 (step G02).

If the determination is No, the variation processing unit 42 sets the permission flag F to 1 (that is, ON) (step G03), and further calculates the following equation (11) that provides the same result as the above equation (10). Te, obtains the period S ₀ of already variations removal (step G04).

Conversely, when it is determined Yes in step G02, the variation processing unit 42C calculates the latest edge interval T ′ ₀ × 2 and obtains the period S ₀ (step G05).

  After steps G04 and G05, the variation processing unit 42C changes the value of the buffer counter C to (C + 1)% 7 (step G06), and ends the process of FIG. 10B.

<< Effects of Fourth Embodiment >>
As described above, according to the present embodiment, the same effects as those of the third embodiment can be obtained by simpler processing.

《Application example》
Next, the image forming apparatus 6 to which the motor control device 1A is applied will be described in detail with reference to FIGS.

  First, in the figure or in the following description, the lowercase letters a, b, c, and d described after the reference numerals mean yellow (Y), magenta (M), cyan (C), and black (Bk). This is a subscript. For example, the photosensitive drum 138a means a yellow photosensitive drum 138.

<< Configuration and operation of image forming apparatus >>
In FIG. 11, an image forming apparatus 6 is, for example, a copying machine, a printer, a facsimile machine, or a multifunction machine having these functions. For example, a full-color image is converted into a sheet Sh (for example, an electrophotographic system and a tandem system). Paper or OHP film). In such an image forming apparatus 6, in addition to the motor control device 1 </ b> A, roughly, a supply unit 7, a registration roller unit 8, an image forming unit 9, a fixing device 10, a discharge roller unit 11, and a discharge unit. And a tray 12.

  The supply unit 7 generally includes a supply tray and a supply roller. The supply tray is configured so that unprinted sheets Sh can be stacked. The supply roller rotates under the control of the motor control device 1A, thereby picking up sheets Sh from the supply tray one by one and sending them out to the conveyance path FP indicated by the broken line in FIG. This sheet Sh is conveyed toward the registration roller unit 8 on the conveyance path FP. Here, the detailed configuration of the motor control device 1A is as shown in FIG. Therefore, in the following description, FIG. 4 may be referred to.

  The registration roller unit 8 includes, for example, a pair of two rollers. The roller pairs are in contact with each other to form a registration nip, and are configured to be rotatable. While the roller pair is stopped, the sheet Sh from the supply unit 7 hits the registration nip and stops temporarily. Thereafter, the roller pair starts to rotate for secondary transfer, and sends the sheet Sh to the secondary transfer area (details will be described later).

  The image forming unit 9 generally includes image forming units 131a to 131d, an exposure device (sometimes referred to as a print head unit) 132, an intermediate transfer belt 133, a driving roller 134, a driven roller 135, and a primary transfer. Rollers 136a to 136d and a secondary transfer roller 137 are included.

  The image forming units 131a to 131d are arranged on a frame (not shown) of the image forming apparatus 6 so as to be linearly arranged from left to right. The image forming unit 131a includes a photosensitive drum 138a of a corresponding color. Around the photosensitive drum 138a, at least a charger 139a and a developing device 140a are provided in this order from the upstream side to the downstream side in the rotation direction (that is, the sub-scanning direction). Similarly, the image forming units 131b to 131d also include at least photosensitive drums 138b to 138d, chargers 139b to 139d, and developing devices 140b to 140d.

  In the image forming unit 9, the chargers 139a to 139d are typically chargers using corona discharge (corotron or scorotron), or chargers using proximity discharge (charging roller or charging brush). These chargers 139a to 139d uniformly charge the peripheral surfaces of the rotating photosensitive drums 138a to 138d (charging process). The exposure device 132 can typically use a so-called laser scanning method or an LED array method. When the exposure device 132 receives image data of each color from the control circuit 8 described later, the exposure device 132 generates light beams Ba to Bd modulated with the image data for each color. The exposure device 132 sequentially scans the peripheral surfaces of the photosensitive drums 138a to 138d charged by the chargers 139a to 139d for each line in the main scanning direction for each line (exposure process). By the above charging / exposure process, electrostatic latent images of corresponding colors are formed on the peripheral surfaces of the photosensitive drums 138a to 138d.

  In the image forming unit 9, the developing devices 140a to 140d supply toners of corresponding colors to the electrostatic latent images formed on the photosensitive drums 138a to 138d (development process). By this development process, Y, M, C, and Bk toner images are formed on the peripheral surfaces of the photosensitive drums 138a to 138d. Here, in the following description, the process from the charging process to the development process may be referred to as an image forming process.

  The intermediate transfer belt 133 is an endless belt stretched between the driving roller 134 and the driven roller 135 so that the outer peripheral surface of the intermediate transfer belt 133 is in contact with the upper end portions of the photosensitive drums 138a to 138d. It is configured to rotate in the direction shown.

  The primary transfer rollers 136a to 136d are arranged so as to press the outer peripheral surface of the intermediate transfer belt 133 and push the inner peripheral surface of the intermediate transfer belt 133 into the photosensitive drums 138a to 138d by a certain amount. Hereinafter, a portion where the intermediate transfer belt 133 and the photosensitive drums 138a to 138d are in contact is referred to as a primary transfer region. A primary transfer voltage having a polarity opposite to that of the toner is applied to each of the primary transfer rollers 136a to 136d. As a result, the toner images on the photosensitive drums 138a to 138d are transferred onto the intermediate transfer belt 133. This process is hereinafter referred to as a primary transfer process. Here, by appropriately adjusting the rotational speed and arrangement of the intermediate transfer belt 133 and the photosensitive drums 138a to 138d, the toner images of the respective colors are sequentially transferred to the same area on the outer peripheral surface of the intermediate transfer belt 133. As a result, a full-color composite toner image is formed on the intermediate transfer belt 133. Such a composite toner image is conveyed to a secondary transfer region described later while being held on the intermediate transfer belt 133 by the rotation of the intermediate transfer belt 133.

  The secondary transfer roller 137 is disposed so as to face the drive roller 134 from the lateral direction with the intermediate transfer belt 133 stretched and supported by the drive roller 134 and the like, and is pushed into the intermediate transfer belt 133 on the transport path FP. Arranged to be. As a result, the intermediate transfer belt 133 and the secondary transfer roller 137 form a secondary transfer nip (in other words, a secondary transfer region). The sheet Sh is fed into the secondary transfer area from the registration roller unit 8. A secondary transfer voltage is applied to the secondary transfer roller 137. As a result, the composite toner image on the intermediate transfer belt 133 is transferred onto the sheet Sh sent to the secondary transfer area. This process is hereinafter referred to as a secondary transfer process. The sheet Sh is sent out from the secondary transfer nip toward the fixing device 10.

  The fixing device 10 typically includes two rotating bodies that are in contact with each other to form a fixing nip. The sheet Sh fed to the fixing nip is heated by one rotating body and rotated by the other. Pressurize with your body. By this fixing process, the synthetic toner image on the sheet Sh is fixed. The fixing device 10 sends the sheet Sh as a printed matter Sh toward the discharge roller unit 11 provided on the downstream side of the transport path FP with respect to the fixing device 10.

  The discharge roller unit 11 rotates under the control of the motor control device 1A. Printed matter Sh sent out by the fixing device 10 is introduced into the discharge roller portion 11. The discharge roller unit 11 sends the introduced printed material Sh to the discharge tray 12.

<< Detailed Operation of Image Forming Apparatus >>
Next, a specific processing flow of the image forming apparatus 6 shown in FIG. 11 will be described with reference to FIG. When receiving the print job, the motor control unit 4 acquires the type of the sheet Sh included in the arrived print job (step H01). In the present embodiment, it is assumed that three types of thin paper, plain paper, and thick paper are defined as types.

Next, the motor control unit 4 determines whether or not the acquired type is thin paper (step H02). If Yes, N in step C04 in FIG. 5 is set to the largest value N _max (for example, 4). (Step H03). Thereafter, the motor control unit 4 executes the process of FIG. 3A. During execution of FIG. 3A, the motor control unit 4 executes the interrupt process of FIG. 5 every time the edge interval T ₀ is input (step H04).

On the other hand, if it is determined No in step H02, the motor control unit 4 determines whether the acquired type is plain paper (step H05). If Yes, N in step C04 in FIG. 5 is an intermediate value. N _mid (for example, 3) is set (step H06). Thereafter, the motor control unit 4 executes the process of FIG. 3A, and executes the interrupt process of FIG. 5 in response to the input of the edge interval T ₀ (step H04).

On the other hand, if NO is determined in step H05, the motor control unit 4 regards the acquired type as cardboard, and sets N in step C04 in FIG. 5 to a minimum value N _min (for example, 2) (step H07). ). Thereafter, the motor control unit 4 executes the process of FIG. 3A, and executes the interrupt process of FIG. 5 in response to the input of the edge interval T ₀ (step H04).

<Effects of application examples>
As described above, according to this application example, N is set to be larger as the sheet Sh is thinner. As a result, with respect to the thin sheet Sh that is easily affected by the rotational fluctuation of the motor 2, N is increased to control the rotational fluctuation of the motor 2 to be small.

<< Appendix 1 >>
In the application example described above, N is set to a different value for each of thin paper, plain paper, and thick paper. However, the present invention is not limited to this, and as shown in FIG. 13, N is set to a relatively large value for thin paper and plain paper, and N is set to a relatively small value for thick paper. It doesn't matter.

<< Appendix 2 >>
In the application example, the case where the processes of FIGS. 3A and 5 are implemented has been described. However, the present invention is not limited to this, and the motor drive control and variation removal processing described in the third embodiment and the fourth embodiment may be implemented.

  The motor control device according to the present invention and the image forming apparatus provided with the motor control device can reduce the variation element included in the composite pulse signal, and are suitable for a copying machine, a printer, a facsimile, and a multifunction machine having these functions. .

1, 1A, 1B, 1C Motor control device 2 Motor 21 Magnet 22U, 22V, 22W Coil 23 Mounting board h1, h2, h3 Detector 3 Motor drive unit 31 Signal processing unit 32 Coil drive unit 33 Signal synthesis unit 4 Motor control unit 41, 41B, 41C Period counting unit 42, 42A, 42B, 42C Variation processing unit 43 Speed control unit 6 Image forming apparatus

Claims (7)

A motor including a mover and a plurality of coils;
A P-phase detector (P is a natural number of 2 or more) provided in the motor, and a P-phase detector that outputs pulse signals having different electrical phase angles from each other by driving the motor;
A signal synthesizer that generates a signal whose logic is inverted every time the logic of any of the output pulse signals of the P-phase detector changes, as a synthesized pulse signal;
A counting unit that sequentially counts the interval between two consecutive edges in the combined pulse signal generated by the signal combining unit;
A variation processing unit for obtaining a cycle of a pulse signal output from any of the P-phase detectors by adding a predetermined number of edge intervals counted by the counting unit;
A speed control unit that controls the energization amount to each of the plurality of coils based on the period obtained by the variation processing unit;
The variation processing unit calculates a period S0 by adding a predetermined number of edge intervals starting from the latest edge interval, and further calculating a predetermined number starting from j (j is a natural number of 2 or more) previous edge intervals. Are obtained by sequentially adding N periods S0, S-1,..., S- (N-1).
The speed control unit is a motor control device that controls the energization amount to each of the plurality of coils based on the addition result S0 + S-1 +... + S− (N−1) in the variation processing unit. A motor including a mover and a plurality of coils;
A P-phase detector (P is a natural number of 2 or more) provided in the motor, and a P-phase detector that outputs pulse signals having different electrical phase angles from each other by driving the motor;
A signal synthesizer that generates a signal whose logic is inverted every time the logic of any of the output pulse signals of the P-phase detector changes, as a synthesized pulse signal;
A counting unit that sequentially counts the interval between two consecutive edges in the combined pulse signal generated by the signal combining unit;
A variation processing unit for obtaining a cycle of a pulse signal output from any of the P-phase detectors by adding a predetermined number of edge intervals counted by the counting unit;
A speed control unit that controls the energization amount to each of the plurality of coils based on the period obtained by the variation processing unit;
The counting unit sequentially counts the interval between two consecutive rising edges and the interval between two consecutive falling edges in the combined pulse signal generated by the signal combining unit,
The variation processing unit
By adding a predetermined number of rising edge intervals counted by the counting unit, a first period of a pulse signal output from any of the P-phase detectors is obtained, and
The second period of the pulse signal output from one of the P-phase detectors is obtained by adding a predetermined number of falling edge intervals counted by the counting unit, and then the first period and Adding the second period;
The speed control unit is a motor control device that controls an energization amount to each of the plurality of coils based on an addition result of the first cycle and the second cycle in the variation processing unit. A motor including a mover and a plurality of coils;
A P-phase detector (P is a natural number of 2 or more) provided in the motor, wherein the electric phase angles differ from each other by driving the motor, and a plurality of cycles are included in one rotation of the motor. A P-phase detector that outputs a pulse signal;
A signal synthesizer that generates a signal whose logic is inverted every time the logic of any of the output pulse signals of the P-phase detector changes, as a synthesized pulse signal;
A counting unit that sequentially counts the interval between two consecutive edges in the combined pulse signal generated by the signal combining unit;
A variation processing unit for obtaining a cycle of a pulse signal output from any of the P-phase detectors by adding a predetermined number of edge intervals counted by the counting unit;
A speed control unit that controls the energization amount to each of the plurality of coils based on the period obtained by the variation processing unit;
The variation processing unit calculates a period S0 by adding a predetermined number of edge intervals starting from the latest edge interval, and further calculating a predetermined number starting from j (j is a natural number of 2 or more) previous edge intervals. Are obtained by sequentially adding N periods S0, S-1,..., S- (N-1).
It said speed control unit, based on the addition result S0 + S-1 + ... + S- (N-1) in the variation processor, that controls the power supply amount to each of said plurality of coils, motors control device. The variation processing unit applies coefficients a0, a-1,..., A- (N-1) (where a0> a) to the N periods S0, S-1,. -1>...> A- (N-1)) and then a0.times.S0, a-1.times.S-1, ..., a- (N-1) .times.S- (N-1). Add,
The speed control unit applies to each of the plurality of coils based on the addition result a0 × S0 + a−1 × S−1,..., + A− (N−1) × S− (N−1) in the variation processing unit. The motor control device according to claim 1 or 3 , which controls an energization amount. A motor including a mover and a plurality of coils;
A P-phase detector (P is a natural number of 2 or more) provided in the motor, wherein the electric phase angles differ from each other by driving the motor, and a plurality of cycles are included in one rotation of the motor. A P-phase detector that outputs a pulse signal;
A signal synthesizer that generates a signal whose logic is inverted every time the logic of any of the output pulse signals of the P-phase detector changes, as a synthesized pulse signal;
A counting unit that sequentially counts the interval between two consecutive edges in the combined pulse signal generated by the signal combining unit;
A variation processing unit for obtaining a cycle of a pulse signal output from any of the P-phase detectors by adding a predetermined number of edge intervals counted by the counting unit;
A speed control unit that controls the energization amount to each of the plurality of coils based on the period obtained by the variation processing unit;
The counting unit sequentially counts the interval between two consecutive rising edges and the interval between two consecutive falling edges in the combined pulse signal generated by the signal combining unit,
The variation processing unit
By adding a predetermined number of rising edge intervals counted by the counting unit, the period of the pulse signal output from any of the P-phase detectors is obtained,
Said counted falling edge interval was by a predetermined number added by the counting unit, Ru seek period of the pulse signal outputted from one of the detectors of the P phase, motors control device. Each of the detectors of the P phase, a Hall element or a rotary encoder, motor control device according to any one of claims 1-5. An image forming apparatus that includes the motor control device according to claim 1 and that prints an image on a sheet, wherein N is different depending on a type of the sheet. Forming equipment.