JPH09137670A - Drive controlling device for motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely detect cycles of pulse signals. SOLUTION: In the case where rise of a pulse signal is detected 111,Y, the value of a timer T1 is stored 113, the timer T1 is reset 115, and the timer T1 is started 117, then the current routine is completed. With the timer T1 started, rise of the next pulse signal detected and the value of the timer T1 stored in the step 113, cycles of pulse signals based on the rise of the pulse signal can be stored in a memory. In the case where fall of a pulse signal is detected 111,N, the value of a timer T2 is stored 133, the timer T2 is reset 135, and the timer T2 is started 137, then the current routine is completed. With the timer T2 started, rise of the next pulse signal detected, and the value of the timer T2 stored in the step 113, cycles of the pulse signals based on the fall of the pulse signals can be stored in a memory.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor drive control device, and more particularly to reversing the drive of a motor by a predetermined amount when the motor load calculated based on the cycle of a pulse signal is larger than a threshold value. The present invention relates to a motor drive control device that stops by stopping.

[0002]

2. Description of the Related Art Conventionally, a motor drive control device has been applied to, for example, a power window device. When the motor drive control device is applied to the power window device as described above, the motor is used to move the door glass up and down, and for example, the detection of foreign matter trapped between the door glass and the window frame is detected. In order to do so, a pulse signal generator that generates a pulse signal in synchronization with the rotation of the motor is provided.

In the pulse signal generator, as shown in FIG. 13 (a), two sliding contacts 46 and 48 (one of which is connected to a power source are connected to a conductor portion 42 and a non-conductor portion 44 provided on a motor shaft. 13) are brought into contact with each other to generate the pulse shown in FIG. In this case, in order to detect the period of the pulse signal with high accuracy, the contact portions of the sliding contacts 46 and 48 are formed at an acute angle, and the time during which the sliding contacts 46 and 48 are in contact with the conductor portion 42 and the non-conductor portion 44. In which current is flowing between the sliding contacts 46 and 48 such that they are equal to each other as T ₁ (hereinafter referred to as an ON state) and a state in which no current is flowing between the sliding contacts 46 and 48 ( Hereafter, the time ratio of the OFF state) is set to 1: 1.

When a foreign object is sandwiched between the door glass and the window frame, the upward movement of the door glass is prevented and, for example, when the foreign object is sandwiched between the door glass and the window frame in the ON state. The ON time is longer than the OFF time, and the ratio of the ON time and the OFF time is 1: 1.
However, the period of the pulse signal from the pulse signal generator becomes long.

Therefore, the power window device smooths the cycle of the eccentric pulse signal by comparing the moving average value of the cycle of the pulse signal including the cycle of the latest pulse signal and the moving average value adjacent to this moving average value. When the difference exceeds the threshold value, it is determined that the foreign matter is caught, and the motor drive is reversed by a certain amount and stopped.

[0006]

However, FIG.
As shown in (a), when the contact portions of the sliding contacts 46 and 48 deteriorate, the time during which the sliding contacts 46 and 48 are in contact with the conductor portion 42 and the non-conductor portion 44 is T ₃ and T ₄ , respectively. To be different. Therefore, as shown in FIG.
The ratio of the time in the N state and the time in the OFF state deviates from 1: 1. If the ratio of the ON state time to the OFF state time deviates from 1: 1, it is erroneously determined that the motor is rotating irregularly, and it is erroneously determined that the foreign matter is caught even though the foreign matter is not caught. The motor drive is erroneously determined to be overloaded and the drive of the motor is reversed by a certain amount and stopped.

An object of the present invention is to solve the above problems and to provide a motor drive controller capable of accurately detecting the period of a pulse signal.

[0008]

In order to achieve the above object, the invention according to claim 1 is a pulse signal generating means for generating a pulse signal in synchronization with the rotation of a motor, and a pulse generated by the pulse signal generating means. Detecting means for detecting rising and falling of the signal; rising of the latest first pulse signal detected by the detecting means; rising of a second pulse signal continuous to the first pulse signal; and the first Cycle calculating means for calculating the cycle of the pulse signal based on the falling edge of the pulse signal and the falling edge of the second pulse signal, and based on the cycle of the first pulse signal calculated by the cycle calculating means. And a motor load detecting means for detecting a motor load and determining whether or not the motor load detected by the motor load detecting means is larger than a threshold value. That the determining means, determination result by said determining means is and a stopping means for stopping by a predetermined amount inversion driving of the motor when a positive determination.

According to a second aspect of the present invention, in the first aspect of the present invention, the motor load detection means has a first cycle of a pulse signal calculated by the cycle calculation means and including a cycle of the first pulse signal. It is characterized in that a difference between one moving average value and at least a second moving average value including a pulse signal period earlier than the pulse signal period of the first moving average value is detected as a motor load.

According to a third aspect of the present invention, in the first aspect of the present invention, the motor load detecting means includes a cycle of the pulse signal calculated by the cycle calculating means and a past pulse that does not include the cycle of the pulse signal. It is characterized in that the difference between the signal cycle and the moving average value is detected as a motor load.

Here, the detecting means of the invention according to claim 1 detects the rising and falling edges of the pulse signal generated in synchronization with the rotation of the motor generated by the pulse signal generating means. The cycle calculating means includes the latest rising edge of the first pulse signal detected by the detecting means, the rising edge of the second pulse signal continuous with the first pulse signal, the falling edge of the first pulse signal, and the second pulse. The period of the pulse signal is calculated based on the falling edge of the signal.

As described above, the rising edge of the first pulse signal, the rising edge of the second pulse signal continuous with the first pulse signal, the falling edge of the first pulse signal, and the falling edge of the second pulse signal. Since the period of the pulse signal is calculated based on this, the periods of the three pulse signals can be obtained from the two pulse signals.

The motor load detecting means detects the motor load based on the cycle of the first pulse signal calculated by the cycle calculating means.

Here, the motor load detecting means is the second aspect.
As in the invention described above, the first cycle of the pulse signal calculated by the cycle calculating means and including the cycle of the first pulse signal.
The difference between the moving average value and the second moving average value including the period of the pulse signal at least past the period of the pulse signal of the first moving average value may be detected as the motor load. Since the second moving average value includes at least the period of the pulse signal that is earlier than the period of the pulse signal of the first moving average value, the first moving average value is earlier than the period of the pulse signal of the first moving average value. The moving average value of only the period of the pulse signal, secondly, at least one cycle of the pulse signal of the past and the period of the pulse signal of the first moving average value before the cycle of the pulse signal of the first moving average value. It is a moving average value with the period of the included pulse signal.

Further, the motor load detecting means is, as in the invention described in claim 3, the moving average of the cycle of the pulse signal calculated by the cycle calculating means and the cycle of the past pulse signal not including the cycle of the pulse signal. The difference from the value may be detected as the motor load.

Then, the judging means judges whether or not the motor load detected by the motor load detecting means is larger than a threshold value, and the stopping means determines whether the motor load of the motor is positive when the judgment result by the judging means is a positive judgment. The drive is reversed by a certain amount and stopped.

As described above, at the rising edge of the first pulse signal, the rising edge of the second pulse signal which is continuous with the first pulse signal, the falling edge of the first pulse signal and the falling edge of the second pulse signal. Since the cycle of the pulse signal is calculated based on the pulse signal, the pulse cycle does not change even if the rising and falling times of the first pulse signal and the rising and falling times of the second pulse signal are different. The period of the pulse signal can be calculated accurately, and the period of the pulse signal obtained by this operation should be calculated more than when the period of the pulse signal is calculated based only on the rising or falling of the pulse signal. Therefore, the overload of the motor can be determined in a short time.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a door 12 on the driver's seat side and one door 14 on the rear seat of a vehicle to which the power window device according to the motor drive control device of this embodiment is applied. Inside each door, a window regulator portion for raising and lowering the door glass 20 is arranged.

As shown in FIG. 2, the window regulator portion 16 on the driver's door side is of a so-called wire type, and has a rotating plate 22A attached to the drive shaft of the motor 22.
The wire is wrapped around. The end of this wire is connected to a holding channel 24 that supports the lower end of the door glass 20, and the holding channel 24 is attached to a main guide 26 so as to be vertically movable. As a result, when the motor 22 rotates in the forward and reverse directions, this rotational driving force is transmitted via the wire, and the door glass 20 moves up and down along the glass guide 18. The configuration of the window regulator unit 16 is not limited to such a wire type, but may be an X arm type or a so-called motor self-propelled type in which the motor itself moves along the rack.

When the door glass 20 is lifted by the motor 22, the peripheral edge portion of the door glass 20 is a rubber weather strip (not shown) in the frame 12A of the door 12.
And the opening of the frame 12A is closed. Also,
When the door glass 20 is moved downward by the rotational driving of the motor 22, the opening of the frame 12A of the door 12 is opened.

The motor 22 includes the door 12 shown in FIG.
Power window master switch 3 attached to 14
0 and the door switch 32 are operated. The door switch 32 is attached to the door 14 other than the driver seat side, and the power window master switch 30 is
It is attached to the door armrest portion 12B of the driver-side door 12. The power window master switch 30 may be attached at any other position as long as it can be easily operated by the driver sitting in the driver's seat.

The power window master switch 30 includes an auto / manual switch 34 for operating the motor 22 of the door 12 automatically or manually and a door switch 36 (mainly for manually operating the motor 22 of each door 14). (Three in the first embodiment)
Is arranged.

The auto / manual switch 34 can be operated in two stages in both directions, and when operating in one stage, the motor 22 of the door 12 is driven only during operation (manual operation), and by operating in two stages, the switch can be operated from the switch. Even if the hand is released, the motor 2 is operated until the door glass 20 reaches a predetermined position.
2 is driven (automatic operation).

The motor 22 is driven when the power window master switch 30 or the door switch 32 is operated to rotate the rotary plate 22A (shown in FIG. 2) in either forward or reverse directions to raise the door glass 20. Or let it fall.

FIG. 3 shows a control circuit 50 for controlling the driving of the motor 22 by operating the power window master switch 30 and the door switch 32. The control circuit 50 is driven by the power supply from the power supply circuit 51. The control circuit 50 includes a computer, a CPU (central processing unit), a RAM, a ROM and an input / output port connected to the CPU via a system bus. The CPU is the entire power window device. The ROM is pre-stored with a program corresponding to a control routine which will be described later. Also, RAM
Functions as a CPU work area. Although FIG. 3 shows the motor 22 for raising and lowering the door glass 20 of the door 12 on the driver's side, the motor 22 for raising and lowering the door glass 20 of the other doors 14 is also the same. It is connected.

As shown in FIG. 3, the control circuit 50 includes a power window master switch 30 or a door switch 3.
2 is connected to the signal line 52 from each switch, and the power window master switch 30 or the door switch 3 is connected.
A drive current for rotating the motor 22 in the forward and reverse directions is supplied according to the operation state of No. 2.

Both ends of the motor 22 whose drive is controlled by the control circuit 50 are closed relay switches 58.
And common terminals 58A, 59A of the open relay switch 59
And the respective first contacts 58B and 59B are connected to the power supply line. Also, the second contacts 58C, 59C
Are each grounded via a resistor R ₀ . In addition,
The contacts of the close relay switch 58 and the open relay switch 59 are switched by the coils 60 and 62, and the motor 22 rotates in the forward and reverse directions by exciting one of the coils 60 and 62.

The motor shaft of the motor 22 is provided with a pulse signal generator 38 for generating pulses in synchronization with the rotation of the motor. As shown in FIG. 4, the pulse signal generator 38 includes a motor shaft 22A and a rotating portion 38A that rotates in synchronization with the rotation of the motor shaft 22A. The rotating portion 38A is provided with a conductor portion 42 formed of a conductor on one half of the peripheral surface and a non-conductor portion 44 formed of a non-conductor on the other half. The rotating portion 38A is provided with a first pulse electrode terminal (sliding contact) 46 and a second pulse electrode terminal (sliding contact) 48 so as to contact the conductor portion 42 and the non-conductor portion 44. A power supply circuit 51 is connected to the first pulse electrode terminal 46, and a control circuit 22 is connected to the second pulse electrode terminal 48.

Next, the control routine of this embodiment will be described with reference to the flowchart shown in FIG. When the first pulse electrode terminal 46 and the second pulse electrode terminal 48 contact the conductor portion 42, the voltage from the power supply circuit 51 becomes a pulse signal, and the first pulse electrode terminal 46, the conductor portion 42, and the second pulse electrode. It is input to the control circuit 22 via the terminal 48.
When the first pulse electrode terminal 46 and the second pulse electrode terminal 48 are in contact with the conductor portion 42 (see point A in FIG. 7A), the pulse signal rises 54 as shown in FIG. 7B. Is detected. On the other hand, the first pulse electrode terminal 46 and the second pulse electrode terminal 48 move from the conductor portion 42 to the non-conductor portion 4
When it contacts 4, the voltage from the power supply circuit 51 is cut off.
When the first pulse electrode terminal 46 and the second pulse electrode terminal 48 are in contact with the non-conductor portion 44 from the conductor portion 42 (see FIG. 7).
7B, the trailing edge 56 of the pulse signal is detected as shown in FIG. 7B.

The routine starts at each of the rise 54 and the fall 56 of the pulse signal thus detected, and in step 102, the period of the pulse signal is detected. The details of the pulse signal cycle detection processing will be described later.

In step 104, the first moving average value A is calculated. Here, the first moving average value A will be described. The control circuit 50 stores n (here, 100) periods of the pulse signals detected by executing this routine. Then, the first moving average value A is the cycle of a plurality of pulse signals including the cycle (101st) of the pulse signal obtained in step 102 (three (99, 99,
It is a moving average value of the 100th and 101st pulse signals).

In the next step 106, the second moving average value B is calculated. The second moving average value B is at least the first
Is the moving average value of the period of the pulse signal including the period of the pulse signal that is earlier than the period of the pulse signal of the moving average value, and is the moving average value of the periods of the 89th, 90th and 91st pulse signals in this embodiment. .

At step 108, the difference C is obtained by subtracting the second moving average value B from the first moving average value A.

In step 110, it is judged whether or not the difference C is larger than the threshold value Th. If the difference C is larger than the threshold value Th, it can be judged that an overload has occurred.
In step 12, the motor is reversed by a certain amount and stopped, and then step 11
Proceed to 4. If the difference C is not larger than the threshold Th, the process proceeds to step 114.

In step 114, the cycle of the oldest pulse signal (the cycle of the first pulse signal, each time this routine is executed, is changed to the cycle of the second, third, ... ), The cycle of the pulse signal detected this time (the cycle of the 101st pulse signal) is stored, and this routine ends.

Next, the routine for detecting the cycle of the pulse signal (step 102) will be described with reference to the flow chart shown in FIG.

In step 111, it is judged whether or not the rising edge 54 of the pulse signal is detected. If the rising edge 54 of the pulse signal is detected, in step 113,
The timer T ₁ value is stored, and in step 115, the timer T ₁ is stored.
(Soft timer) is reset, the timer T ₁ is started in step 117, and this routine is finished. In this way, the timer T ₁ is started in step 117, the rising edge of the next pulse signal is detected, and the value of the timer T ₁ is stored in step 113. Therefore, as shown in FIG. The time from 54 to the next rising edge 54 of the pulse signal can be stored, and the period of each of the pulse signals P ₁ , P _3, ... Can be stored.

If the determination in step 111 is negative, steps 133 to 137 are executed, but in steps 133 to 137, if the rising edge of the pulse signal is changed to the falling edge and T ₁ is replaced with T ₂ , respectively. Since each corresponds to steps 113 to 117, detailed description thereof will be omitted. By storing the timer T ₂ value in step 133, the time from the fall 56 of the pulse signal to the fall 56 of the next continuous pulse signal can be stored, as shown in FIG. 7B. Therefore, each cycle of the pulse signals P ₂ , P _4, ... Can be stored.

As described above, according to this embodiment, the first
Even if the contact time between the pulse electrode terminal and the second pulse electrode terminal deteriorates and the time ratio of the ON state and the OFF state deviates from 1: 1, one cycle of the pulse signal is obtained if no foreign matter is caught. Does not change, the time from the rise of the pulse signal to the rise of the next continuous pulse signal and the time from the fall of the pulse signal to the fall of the next continuous pulse signal do not change, and the pulse signal The cycle can be detected.

Further, either the time from the rise of the pulse signal to the rise of the next continuous pulse signal or the time from the fall of the pulse signal to the fall of the next continuous pulse signal, for example, the rise of the pulse signal When the time from the pulse signal to the next continuous rising edge of the pulse signal is detected, as shown in FIG. 7C, pulse signals S ₁ , S ₂ ,
The cycle of ... Is detected. On the other hand, according to the present embodiment, the time from the rising of the pulse signal to the rising of the next consecutive pulse signal and the time from the falling of the pulse signal to the falling of the next consecutive pulse signal are each continuous. since it is detected Te, pulse signal P ₂ with the pulse signal P _1, P ₃ ··· and reference fall relative to the rise of the pulse signal shown in FIG. 7 (b), P ₄ ··· Each cycle of is detected. Therefore, according to this embodiment, the period of the pulse signal can be detected three times as shown in FIG. 7B before the period of the pulse signal is detected twice as shown in FIG. 7C. Therefore, it is possible to judge in a short time whether or not a foreign substance is caught.

As described above, in this embodiment, the pulse signal generator sets the ratio of the ON state time and the OFF state time to 1: 1.
However, the present invention is not limited to this, and the ON state time is shorter than the OFF state time and the OFF state time is shorter than the ON state time. Good.

That is, in the example shown in FIG. 8A, the conductor portion 44 is partially provided on one side of the rotating portion 38A.
The non-conductor portion 44 inserted in a direction (X direction) intersecting with the rotation direction of the first pulse electrode terminal 46 and the second pulse electrode terminal 48 is provided. Are arranged in the X direction. As a result, the second pulse electrode terminal 48 is always in contact with the conductor portion 42, and the first pulse electrode terminal 46 is in contact with the conductor portion 42 per revolution of the motor for a shorter time than the non-conductor portion 44. Therefore, as shown in FIG.
The time in the N state is shorter than the time in the OFF state.

Further, in the example shown in FIG. 8B, the rotating portion 3
8A is provided with a non-conductor portion 44 in which a conductor portion 44 is partially inserted in a direction (X direction) intersecting the rotation direction of the rotating portion 38A, and each of the first pulse electrode terminal 46 and the second pulse electrode terminal 48 is provided. The contact points of are arranged in the X direction. As a result, the contact time of the first pulse electrode terminal 46 and the second pulse electrode terminal 48 with the conductor portion 42 per one rotation of the motor is shorter than the contact time with the non-conductor portion 44. Therefore, as shown in FIG. 9, the time in the ON state is shorter than the time in the OFF state.

In both of the examples shown in FIGS. 8A and 8B, the ON state time is shorter than the OFF state time as shown in FIG. 9, but the continuous pulse signal rises and rises. Since the time between the falling edges is the same, it is possible to accurately detect the period of the pulse signal, and it is possible to determine in a short time whether or not a foreign substance is caught.

The conductor portion 4 shown in FIGS. 8 (a) and 8 (b) is used.
2 is a non-conductor, and the non-conductor part 44 is a conductor,
The time in the OFF state may be shorter than the time in the ON state.

Further, in the above-mentioned embodiment, the predetermined threshold value is used, but the present invention is not limited to this, and changes with a delay and follow the change of the motor load. You may make it use the threshold value.

That is, a constant voltage is supplied from the power supply circuit 51 to the motor 22, and the rotation speed of the motor 22 for raising the door glass 20 corresponds to the motor load.
The rotation speed of the motor 22 corresponds to the cycle of the pulse signal generated by the pulse signal generator 38. Therefore, the cycle of the pulse signal corresponds to the motor load.

By the way, the rotation speed of the motor 22 for raising the door glass 20 is constant if there is no pulsation or the like. Therefore, the period of the pulse signal from the pulse signal generator 38 is also constant.

However, pulsation is generally generated in the motor. Therefore, the motor load due to this pulsation changes, and the cycle of the pulse signal changes. Therefore, the threshold value is set high so as not to erroneously detect that a foreign object is caught when the foreign object is not caught by the variation of the period of the pulse signal.

Furthermore, the coefficient of friction of the regulator mechanism for moving the door glass, etc., increases due to variations in each power window device, changes over time, temperature, etc., and along with this, the period of the pulse signal due to the above-mentioned pulsation. The threshold value is set higher to prevent erroneous detection due to the increased amount of change in the motor load.

When the threshold value is set high in this way, the motor load that can detect the entrapment of foreign matter becomes high. In other words, the threshold value is set high even if foreign matter is caught when the friction coefficient of the regulator mechanism is small and the motor load accompanying normal movement of the door glass is small. Even if it is, it is determined that it is not overload, and the motor load that is determined to be overload increases.

Therefore, if a threshold value that changes with a delay and follows the change of the motor load is used, the threshold value should be set to a high constant value so as not to be judged as an overload due to the change amount of the motor load due to pulsation. Even if it is not, it is possible to properly judge whether it is overload or not. It is possible to obtain the effect that the applied motor load can be reduced.

By the way, in step 114 of the main routine (FIG. 5), the cycle of the pulse signal detected this time is stored instead of the cycle of the oldest pulse signal. Therefore, the cycle of n pulse signals including the cycle of the pulse signal detected this time is stored. Therefore, if the third moving average value of the cycle of the n pulse signals is calculated and stored after step 114, when the main routine is executed next time, the step between step 108 and step 110 is performed. In, the threshold value shown in FIG. 10 can be fetched based on the stored third moving average value and used as the threshold value in step 110. It should be noted that this threshold value is a change amount that exceeds the change amount (noise) of the cycle of the pulse signal caused by the pulsation described above and that can be determined not to be overload. As shown in FIG. 10, the relationship between the third moving average value and the threshold value is not limited to be stored as a map, and a data table storing the third moving average value and the threshold value in association with each other. May be used to obtain the threshold value from the third moving average value by a complementary method, and a relational expression indicating the relationship between the third moving average value and the threshold value may be stored to store the third moving average value. The threshold value may be obtained based on the average value and this relational expression.

Since the third moving average value for fetching the threshold does not include the cycle of the pulse signal captured this time (the cycle of the latest pulse signal), the threshold is the motor load ( It changes with a delay and following the change of the pulse signal period).

As described above, the present invention is as follows by using the threshold value which changes with delay and follow the change of the motor load.

A pulse signal generating means for generating a pulse signal in synchronization with the rotation of the motor, a detecting means for detecting the rising and falling edges of the pulse signal generated by the pulse signal generating means, and a change in the motor load. Setting means for setting a threshold that changes with delay and following
The latest rising edge of the first pulse signal detected by the detecting means and the second rising pulse that follows the first pulse signal.
Cycle calculating means for calculating the cycle of the pulse signal based on the rising edge of the pulse signal, the falling edge of the first pulse signal, and the falling edge of the second pulse signal; Motor load detecting means for detecting a motor load based on the cycle of the first pulse signal, and determining whether or not the motor load detected by the motor load detecting means is larger than a threshold value set by the setting means. A motor drive control device comprising: a determination unit for performing a predetermined amount, and a stop unit for reversing and stopping the driving of the motor by a predetermined amount when the determination result by the determination unit is a positive determination.

It should be noted that the motor load detection means includes a first moving average value of the cycle of the pulse signal calculated by the cycle calculating means and including the cycle of the first pulse signal, and at least the first moving average value. The difference from the second moving average value including the period of the pulse signal in the past from the period of the pulse signal of is detected as the motor load.

Further, the setting means may set the threshold value based on the third moving average value of the pulse signal period excluding the first pulse signal period. Since the period of the first pulse signal is excluded in this way, the first moving average value changes in response to a change in the motor load, but changes following it.

In the above-described embodiment, 100 detected pulse signal periods are stored, but the value is not limited to 100. Also, the first and second moving average values are moving average values of the period of three pulse signals, but this value is not limited to three and may be other than three, and different numbers of pulse signals may be used. It may be a moving average value of the period.

Next, a second embodiment of the present invention will be described. The configuration of this embodiment is the same as that of the above-described first embodiment, and the description thereof is omitted.

Next, the control routine of this embodiment will be described with reference to the flow chart shown in FIG. As described above, this routine is started each time the rising edge 54 and the falling edge 56 of the pulse signal are detected, and in step 102, the period P _n of the pulse signal is detected. The process of detecting the cycle of the pulse signal P _n is performed by the above-described first
Since it is the same as the embodiment described above, the description thereof will be omitted.

At the next step 124, the moving average value P ₀ is calculated. Here, the moving average value P ₀ will be described. The control circuit 50 executes n cycles of the pulse signal detected by executing this routine (16 cycles in this embodiment, 1 cycle in this case).
(Not limited to 6). The moving average value P ₀ is the period of a plurality of past pulse signals that does not include the period of the pulse signal P _n obtained in step 102 (16 (P _n-16 , P _n-15 , ... P _n-1 )) is a moving average value.

At step 126, the moving average value P ₀ is subtracted from the pulse signal P _n to obtain the difference C.

At step 128, it is determined whether the difference C is larger than the threshold Th. The threshold value Th is a function stored in advance corresponding to the moving average value P ₀ as shown in FIG. 12, and is stored as a map. Therefore, in step 128, the threshold value Th is fetched from this map based on the moving average value P _0, and it is determined whether or not the difference C is larger than this threshold value Th. The present invention is not limited to the case of storing as a map, is stored in a data table may be calculated threshold Th by complementation method based on the moving average value P _0, the moving average value P ₀ and the threshold The relational expression indicating the relation with the value Th is stored,
Based on this relational expression and the moving average value P ₀ , the threshold value Th
May be requested.

When the difference C is larger than the threshold Th,
It can be determined that it is overloaded, and in step 130, the motor is reversed by a certain amount and stopped, and the process proceeds to step 132. If the difference C is not larger than the threshold Th, the process proceeds to step 132.

In step 132, the cycle of the oldest pulse signal (P _n-16 , each time this routine is executed,
P _n-15 , P _n-14 , ...), the cycle P _n of the pulse signal detected this time is stored, and this routine ends.

In the above-described first and second embodiments, the pulse signal generator having two sliding contacts is used, but the present invention is not limited to this, and a motor shaft is provided. The provided rotary encoder may be used as the pulse signal generating means.

[0069]

As described above, the present invention has the effect that the period of the pulse signal can be accurately obtained and the overload of the motor can be determined in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram showing mounting positions of a power window master switch and a door switch.

FIG. 2 is an explanatory view showing a structure for raising and lowering a door glass of a power window device.

FIG. 3 is a block diagram showing a control system of a power window device to which the motor drive control device of the first embodiment is applied.

FIG. 4 is a diagram showing details of a pulse signal generator.

FIG. 5 is a flowchart showing a main routine of this embodiment.

FIG. 6 is a flowchart showing a subroutine of step 102 of the main routine.

FIG. 7 is an explanatory diagram illustrating a principle of detecting a cycle of a pulse signal.

FIG. 8 is a modification of the pulse signal generator.

FIG. 9 is an explanatory diagram illustrating a principle of detecting a cycle of a pulse signal from a pulse signal generator of a modified example.

FIG. 10 is a diagram showing a relationship between a third moving average value according to a modified example of the present embodiment, a variation amount of a period of a pulse signal, and a threshold value.

FIG. 11 is a flowchart showing a main routine of the second embodiment.

FIG. 12 is a map showing a relationship between a moving average value and a threshold value.

FIG. 13 is an explanatory diagram illustrating a conventional principle of detecting a cycle of a pulse signal.

FIG. 14 is an explanatory diagram illustrating the principle that the periods of ON and OFF pulse signals differ when the sliding contact deteriorates.

[Explanation of symbols]

 22 control circuit 38 pulse signal generator 42 conductor part 44 non-conductor part 46 first pulse electrode contact 48 second pulse electrode contact 51 power supply circuit

Claims (3)

[Claims] 1. A pulse signal generating means for generating a pulse signal in synchronization with rotation of a motor, a detecting means for detecting rising and falling edges of a pulse signal generated by the pulse signal generating means, and the detecting means. The detected latest rising edge of the first pulse signal and the second rising edge that is continuous with the first pulse signal.
Cycle calculating means for calculating the cycle of the pulse signal based on the rising edge of the pulse signal, the falling edge of the first pulse signal, and the falling edge of the second pulse signal; A motor load detecting means for detecting a motor load based on the cycle of the first pulse signal; a judging means for judging whether or not the motor load detected by the motor load detecting means is larger than a threshold value; A motor drive control device comprising: a stop unit that reverses and stops the drive of the motor by a predetermined amount when the result of the determination by the unit is a positive determination. 2. The motor load detection means includes a first moving average value of a cycle of a pulse signal calculated by the cycle calculating means and including a cycle of the first pulse signal, and at least the first moving average value. The motor drive control device according to claim 1, wherein a difference between the pulse signal cycle and the second moving average value including a cycle of the pulse signal in the past is detected as a motor load. 3. The motor load detection means is a moving average value of the cycle of the first pulse signal calculated by the cycle calculation means and the cycle of past pulse signals not including the cycle of the first pulse signal. 2. The motor drive control device according to claim 1, wherein a difference between and is detected as a motor load.