JP4845013B2 - Position measuring device - Google Patents

Description

The present invention counts the pulse edge of one of the pulses output from a pulse generator that outputs two sine wave pulses out of phase in accordance with the drive amount, and moves or moves the position of the driven member. In particular, a position measuring device suitable for use with a vehicle sliding door in which a hatch back door of an automobile or the like or a sliding door provided on a side surface of a vehicle is opened and closed by a driving source such as a motor. About.

  Conventionally, a door opening / closing device that automatically opens and closes a rear door (hatchback door) of a vehicle, or a sliding door that can slide in the front-rear direction is attached to the side of a vehicle body such as an automobile. 2. Description of the Related Art An automatic opening / closing device for a sliding door for a vehicle that is opened and closed by a driving source is known.

  This device operates a door opening / closing operator provided near the driver's seat or the door handle, or operates a wireless remote controller from outside the vehicle, and activates a drive source by a control device installed in the vehicle, The hatchback door and slide door are automatically opened and closed or moved to open and close.

  In these hatchback doors and sliding doors for vehicles, when a door in a fully closed position is driven in the opening direction by a drive source, the door is driven after the door lock mechanism is released, and the opened door is closed. In this case, the door is driven in the closing direction and locked in the fully closed position. The door opening / closing operation is driven by a drive source such as a motor, and the opening / closing operation is controlled based on door position data output from the position detection device. The position data of the sliding door is calculated by the position detection device based on the output pulse of a pulse generator such as an encoder or Hall IC provided in a driving source such as a motor or operating in conjunction with the movement of the door. .

Therefore, if this position data is incorrect, there is a possibility that the door lock control and the opening / closing operation control may be defective and the door mechanism may be damaged, and the door may not be opened or closed. For example, in the automatic door opening / closing control device described in Patent Document 1, the position data of the actual closed position of the sliding door and the closed position calculated by the position detection device while controlling the driving device and adjusting the pressing strength of the sliding door, etc. And is consistent. The aligned position data is stored and used as subsequent control data. In the invention described in Patent Document 2, in a motor speed control device that controls the motor speed by detecting the motor speed using an encoder with a two-phase pulse output, a duty imbalance amount and a predetermined position between the two-phase pulses are determined. The stationary phase error is converted into the number of pulses from the phase difference to correct the pulse count error.
JP 2001-254567 A Japanese Patent Laid-Open No. 10-90293

  However, as in the invention described in Patent Document 1, even if the actual position of the slide door and the position data are aligned and stored correctly, an abnormality occurs in the pulse output from the drive source during the operation of the slide door. Or, when noise is picked up due to a momentary power interruption or the like, a pulse abnormality may occur.

  If the position data is erroneously counted due to the occurrence of these abnormal pulses, the data of the position detection device becomes incorrect, and a deviation occurs between the actual door position and the position data of the position detection device. When such a shift occurs, the door opening / closing control unit cannot correctly control the door opening / closing mechanism. For example, if the power supply is repeatedly interrupted, pulsed noise is generated in the encoder output, and erroneous counting may occur due to noise edges.

  An object of the present invention is to provide a position measuring device capable of preventing erroneous pulse counting due to a momentary power interruption or the like.

Means and effects for solving the problems

In order to solve the above-described problem, the position measuring device according to claim 1 is configured to output either one of the phase-shifted A-phase and B-phase sine wave pulses according to the driving amount. In a position measurement device that measures the movement amount or movement position of a driven member by counting the pulse edges of the pulse, when the interval between the rising or falling edges of the A-phase pulse and the B-phase pulse is less than a predetermined value , depending on the order of the a-phase pulse edges or the B-phase pulse edges appear in succession, Bei give a count correction unit stops the pulse count, or to correct the count value,
The count correction unit monitors a continuous pulse edge interval, and determines an abnormality when the continuous pulse edge interval is a predetermined value or less; and
A correction control unit that corrects the count value according to the generation order of the continuous pulse edges determined to be abnormal according to a predetermined algorithm stored in advance when the edge monitoring unit determines that the abnormality is present;
When the two consecutive pulse edges determined to be abnormal change from the pulse edge of the non-counting phase to the pulse edge of the phase to be counted, the correction control unit stops counting by the adjacent pulse edge and performs two consecutive When the pulse edge to be changed changes from the pulse edge of the phase to be counted to the pulse edge of the non-count phase, the count value by the pulse edge determined to be abnormal is returned to the previous count value .

  In this aspect, when it is determined that the pulse is abnormal when the pulse edge interval is equal to or smaller than a predetermined value, correction processing is performed according to the order of the pulse edges that appear successively. Accordingly, by storing correction values in accordance with the characteristics of abnormal pulses such as instantaneous power interruption, it is possible to correct the counts due to these abnormal pulses.

In addition, in this aspect, the feature of the abnormal pulse is simply stored and not only corrected when matched, but also by storing a predetermined correction algorithm that matches the feature pattern of the abnormal pulse. Correction processing is performed based on an algorithm. This makes it possible to perform correction processing more quickly and easily.

Furthermore, this aspect exemplifies an example of an algorithm for correcting a count by abnormal pulse edges that have occurred twice in succession when a power supply is instantaneously interrupted. For example, when +1 is counted at the first pulse edge of two consecutive abnormal pulses, the count value is corrected to be decremented by -1 at the pulse edge of the subsequent non-counting phase, and conversely at the first pulse edge. When −1 is counted, correction is performed so that the count value is incremented by 1 at the pulse edge of the subsequent non-counting phase. This makes it possible to correct (correct) an incorrect count value due to an instantaneous power interruption.

The position measuring apparatus according to claim 2 , further comprising: counting a pulse edge of the phase to be counted immediately before by the correction processing of the correction control unit when the pulse edge is determined to be abnormal for four consecutive times. When the operation is stopped, the correction process is stopped at the subsequent pulse edge of the non-counting phase. This mode is an example of an algorithm for correcting a part of two consecutive pulse edges in order to correct a count due to abnormal pulse edges that occurred four consecutive times at the time of instantaneous power interruption. When the correction process is performed by the preceding abnormal pulses generated continuously, the correction process for counting +1 or -1 is stopped under a predetermined condition. Thereby, it is possible to more accurately correct the count error at the time of instantaneous power interruption.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram schematically showing the configuration of an open / close control device for a vehicle sliding door that is opened and closed by a drive unit 11 such as a motor. In the figure, the sliding door opening / closing control device 10 includes a sliding door 50, a driving unit 11, a driving circuit 12, a door opening / closing control unit 13, a position measuring unit 14, and a transmission mechanism 30. Further, at the position where the slide door 50 is closed, a closed position sensor unit 15 such as a limit switch for detecting that the slide door 50 is in the closed position and a closed position latch unit 16 for maintaining the slide door in the closed position are provided. If necessary, an open position sensor unit 17 such as a limit switch and an open position latch unit 18 for maintaining the slide door in the open position can be provided at the fully open position.

  The slide door 50 is driven in the left-right direction by a drive unit 11 such as a motor via a transmission mechanism such as a belt 30. The drive unit 11 is provided with an encoder 19 and the like provided on the rotating shaft, and outputs pulses of two phases, A phase φ1 and B phase φ2, which are shifted from the encoder 19 by ¼ cycle. The pulse generator 19 only needs to generate a pulse in synchronization with the movement of the door, and is not necessarily provided on the rotating shaft of the drive unit 11.

  The opening / closing control unit 13 controls the driving circuit 12 in accordance with the door opening command and the door closing command to control the operation of the driving unit 11, thereby opening and closing the sliding door 50, the latch units 16 and 18, and a lock mechanism (see FIG. (Not shown) and the like are controlled. The opening / closing control unit 13 performs opening / closing of the sliding door 50, latch activation / release, lock activation / release, and the like based on the position data from the position measurement unit 14, the data from the closed position sensor unit 15, the open position sensor 17, and the like. Take control.

  When the drive unit 11 is driven, as shown in FIG. 1, the A phase φ1 and the B phase φ2 which are pulse sine waves whose phases are shifted by 90 degrees are output from the encoder 19. The position measuring unit 14 recognizes the position of the sliding door by counting the rising edge or falling edge of the phase.

  This will be described in more detail with reference to FIG. FIG. 5 is a diagram for explaining the principle of pulse counting of A-phase and B-phase pulses when the drive unit is driven in the positive direction. The rotational direction of the drive unit, that is, the moving direction of the sliding door can be known from the states of the A phase (pulse Aφ1) and the B phase (pulse Bφ2). As shown in FIG. 5, when the A phase is 90 degrees ahead of the B phase, the rotation is in the positive direction, the rising and falling edges of the B phase are counted, and the count number is used as position data. The case will be described. In this case, the rising edge of the B phase appears when the A phase is at the high level (hereinafter referred to as “H level”), and the B phase when the A phase is at the low level (hereinafter referred to as “L level”). When the falling edge of appears, it can be seen that the A phase has advanced by 90 degrees from the B phase first, so that it is understood that the rotation is in the positive direction. Therefore, in this case, every time a B-phase edge is detected, the cumulative count is incremented by one. As the pulse count increases, the amount of movement in the positive direction increases.

  Conversely, when the B phase rises when the A phase is at the L level and the B phase falls when the A phase is at the H level, it can be seen that the phase of the B phase has advanced further. It turns out that it is rotating to the direction (refer FIG. 1). Therefore, in this case, every time a B-phase edge is detected, the cumulative count is decremented by 1 (decrement).

  In this way, the position measurement unit 14 generates the cumulative count number while counting (incrementing or decrementing) the pulse number. The cumulative count number indicates the amount obtained by subtracting the forward direction drive amount and the reverse direction drive amount of the drive unit 11, so that it indicates the drive amount of the drive unit, that is, the position of the slide door. Therefore, by associating the accumulated count value with the actual position of the sliding door, it can be used as the position data of the sliding door.

  For example, the slide door is set to the closed position with the count number “0”, and the count number increases each time the door is opened. When the count number is 10,000, the fully open position is obtained. Conversely, when the door is closed from the fully opened position, the cumulative count is decremented when moving from the count number 10000 in the closing direction, and becomes zero when the slide door is closed.

  When the A-phase and B-phase pulses appear normally, the A-phase and B-phase are 90 degrees out of phase, so the A-phase edge interval and the B-phase edge interval should be constant. However, when noise or the like occurs, the interval between the pulse edges becomes non-uniform. The normal pulse edge interval becomes shorter as the drive speed (rotational speed) of the drive device becomes faster. However, since the maximum speed of the drive device is limited, the shortest pulse edge interval in the normal case can be predicted.

  For example, when an instantaneous power interruption occurs, an error may occur in the encoder pulse count. FIG. 6 shows the immunity waveform used for the power interruption test. An inductive load shedding test was performed by applying such an immunity waveform.

  The position measuring apparatus of the present invention corrects the pulse count when a pulse abnormality occurs due to such a momentary power interruption or the like so that the pulse count value (position data) can be kept normal. This will be described with reference to FIG. FIG. 2 is a functional block diagram showing an embodiment of the position measuring apparatus of the present invention. A counting unit 21, an edge detection unit 22, and a count correction unit 23 are provided. The count correction unit 23 further includes a correction control unit 26, an abnormality detection unit 27, and an algorithm storage unit 28. The output from the pulse encoder 19 is input to the counting unit 21 and the edge detection unit 22. The edge detector 22 detects the pulse edges of both the A-phase pulse and the B-phase pulse. The pulse edge detected by the edge detection unit 22 is output to the abnormality detection unit 27. The abnormality detection unit 27 determines that there is an abnormality when the interval between successive pulse edges is equal to or less than a predetermined value (including simultaneous cases). If determined to be abnormal, the correction control unit 26 is notified of the abnormal state. When notified of the abnormal state, the correction control unit 26 refers to the algorithm storage unit 28 to execute correction processing according to the order of appearance of the pulse edges determined to be in the abnormal state. Correct the numerical value.

  FIG. 3 and FIG. 4 show an example of a correction algorithm in the case where the A-phase B-phase pulse falls from high to low in a state of being almost simultaneously or slightly shifted due to an instantaneous power interruption or the like. In the figure, “→” indicates a case where the pulse edges shown on the left and right sides are generated from the left to the right for a short period of time or substantially simultaneously, and “˜” indicates that the pulse edge is spaced at a predetermined time interval or more. The case where the pulse edge shown to the left and right generate | occur | produces is shown. Further, “+” indicates a plus 1 count, and “−” indicates a −1 count. “X” means correction for stopping the count, and “correction” means that correction is performed to return the value counted at the B-phase edge of the abnormal pulse edge to the value immediately before the count (−1 or +1). To do. “*” Means that correction is stopped.

  The basic correction algorithm shown in FIG. 3 and FIG. 4 performs correction and other irregular processes at the timing of the subsequent pulse edge of two consecutive abnormal pulse edges. When two consecutive pulse edges change from a pulse edge of a non-count waveform (A phase) to a pulse edge of a count waveform (B phase), even if the subsequent pulse edge is a count pulse, When counting is stopped (B phase counting is stopped) and two consecutive pulse edges change from the pulse edge of the count waveform (B phase) to the pulse edge of the non-count waveform (A phase), the count value is immediately before that. The count value is returned to -1 (-1 or -1 is counted).

  FIG. 3A shows a case in which two falling pulse edges of the A phase and the B phase are continuous at a short interval or at the same time due to a momentary power interruption, and two rising edges are continued at a certain interval, and then at the pulse edge, +1 The case where is detected is shown.

  (1) in FIG. 3A shows a correction algorithm when the pulse edge changes from B → A to B → A. First, since the B phase appears, +1 is counted, and the A phase appears continuously in a short time, so that the previous +1 is corrected downward (to -1). Next, after a little time has elapsed, the B phase appears, so further counting is performed (+1), and the next A phase is corrected (-1). Thus, the final pulse count becomes 0, and the instantaneous interruption pulse does not affect the count value.

  (2) in FIG. 3A shows a case where the B phase is a long instantaneous interruption pulse and a relatively short A phase instantaneous interruption pulse is included in the B phase instantaneous interruption pulse. In this case, the edges appear in the order of B → AA → B. In this case as well, the B phase is counted (+1) and the A phase is corrected. Since the next abnormal two consecutive pulse edges are A → B, they are not counted even in the B phase. (3) shows the case where the A phase appears first (A → BA → B). In this case, since the non-count pulse A phase appears first, none of the B phases are counted. (4) is the opposite of (2) and is the case where the B phase is short. If the A phase appears first, the B phase is not counted, and if the B phase appears first, the correction is made (-1) when the A phase appears.

  FIG. 3B shows a case where the falling and rising pulse edges of the A phase and the B phase appear at a short interval or simultaneously four times due to a short power interruption. In this case, some special modifications are added to the above-described two continuous pulse correction algorithm. The correction means that when the count pulse edge immediately before the occurrence of the abnormality is not counted by the abnormality correction algorithm, the subsequent non-count pulse edge in the abnormal state is not corrected by −1 (correction stop). .

  Examples are shown in (5) and (7) of FIG. In (5), B → A → B → A continues with a short pulse edge interval. The first B → A and the next A → B are the same as the two consecutive algorithms. However, since the last B → A does not count the B phase, this special condition is met and A Do not correct by phase. Similarly, in the case of (7), in the second B → A of A → B → A → B, since the count is not performed in the B phase, the correction is not performed in the A phase. Note that (6) and (8) in FIG. 3 (b) are the same algorithm as in the case of two consecutive, and will not be described.

  As described above, by correcting the occurrence of an incorrect pulse count by a predetermined algorithm according to the abnormal pulse pattern peculiar to the instantaneous power interruption, an erroneous count due to the instantaneous power interruption can be corrected correctly. It becomes possible. As a result, the correct count value can be maintained even in the case of instantaneous power interruption.

  Although FIGS. 3A and 3B show the correction algorithm when +1 is detected at the pulse edge, the same correction processing is performed when −1 is detected at the pulse edge. However, in this case, since the count is reversed, when −1 is detected at the pulse edge, +1 is performed in the correction process for returning to the previous state. The correction processing algorithm in this case is shown in FIGS. The correction process of FIG. 4 is different from the case of FIG. 3 in that −1 is counted at the B-phase pulse edge and +1 is counted as the correction process, and the other points are exactly the same. do not do.

  By the correction as described above, an incorrect count value due to a power supply interruption can be corrected to a correct value. However, an error in the count value may not be corrected due to irregular and random noise. In such a case, it is desirable that the position data be recovered and corrected by the following processing.

  For example, when the count value (position data) is deviated in a more open direction than the actual slide position due to noise or the like, the open / close control unit 13 is actually in the closed or half-door state. May recognize that the sliding door 50 is open based on erroneous position data from the position measuring unit 14. In this case, even if a door opening command is issued, the door cannot be opened.

  Therefore, when such a pulse count abnormality is found, the opening / closing control unit 13 forcibly corrects the pulse count value (position data) of the position measurement unit to a correct value. That is, when the closed position sensor unit 15 provided at the closed position of the slide door 50 detects that the slide door is closed, the position data of the position measuring unit 14 is a predetermined position indicating a predetermined closed position. If the current position data is not within the range, it is assumed that an error has occurred in the current position data, and the position measurement unit data is forcibly reset to the closed position data. As a result, the count value and the position of the slide door 50 can be matched, so that it is possible to return to the correct control.

It is a block diagram which shows typically the structure of the opening / closing control apparatus of the sliding door for vehicles which opens and closes by drive parts, such as a motor. It is a functional block diagram showing one embodiment of a position measuring device of the present invention. Book An example of a correction algorithm when the A-phase and B-phase pulses fall from high to low in a state where they are almost simultaneously or slightly shifted due to an instantaneous power interruption is shown. An example of a correction algorithm in the case where −1 is counted when the A-phase and B-phase pulses are almost simultaneously or slightly shifted due to a momentary power interruption and falls from high to low is shown. It is a figure explaining the principle of the pulse count of an A-phase and a B-phase pulse when a drive part is driven to the positive direction. The immunity waveform used for the power interruption test is shown. A case where the fall time is thus shifted is schematically shown in the form of a sine wave pulse.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sliding door opening / closing control apparatus 11 Drive part 12 Drive circuit 13 Opening / closing control part 14 Position measurement part 15 Closed position sensor part 16 Closed position latch part 17 Open position sensor part 21 Counting part 22 Edge detection part 26 Correction control part 27 Abnormality detection part 28 Algorithm storage

Claims (2)

The amount of movement or movement of the driven member is counted by counting the pulse edges of one of the pulses output from the pulse generator that outputs the A-phase and B-phase sine wave pulses out of phase according to the driving amount. In a position measuring device for measuring a position, according to the sequence of A-phase pulse edges or B-phase pulse edges that appear continuously when the interval between the rising or falling edges of the A-phase pulse and the B-phase pulse is equal to or less than a predetermined value. Te, Bei give a count correction unit stops the pulse count, or to correct the count value,
The count correction unit monitors a continuous pulse edge interval, and determines an abnormality when the continuous pulse edge interval is a predetermined value or less; and
A correction control unit that corrects the count value according to the generation order of the continuous pulse edges determined to be abnormal according to a predetermined algorithm stored in advance when the edge monitoring unit determines that the abnormality is present;
When the two consecutive pulse edges determined to be abnormal change from the pulse edge of the non-counting phase to the pulse edge of the phase to be counted, the correction control unit stops counting by the adjacent pulse edge and performs two consecutive When the pulse edge to be changed changes from the pulse edge of the phase to be counted to the pulse edge of the non-count phase, the count value by the pulse edge determined to be abnormal is returned to the previous count value. 2. The position measuring device according to 2. Furthermore, when the pulse edge is determined to be abnormal for four consecutive times and the count of the pulse edge of the previous phase to be counted is stopped by the correction processing of the correction control unit, the subsequent non-count phase position measuring device according to claim 1, characterized that you cancel the correction process in the pulse edge.

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