JPH08192656A - Control device of automatic transmission for vehicle - Google Patents

Abstract

PURPOSE: To prevent failure diagnosis of a shift step from being carried out by an error, when a reverse range switch is abnormal. CONSTITUTION: This control unit is constituted so that signal patterns from a vehicle speed sensor differ with the rotational directions of a rotor 11 by devicing the form of the rotor 11. When a CPU 9h judges the advancing direction of a vehicle based on the signal from the vehicle speed sensor 1 and this judged result is inconsistent with the signal from an actual R range SW (reverse range switch) 2b, the R range SW 2b is judged to be abnormal, and the control unit 9 is constituted so that at abnormality of the R range SW 2b, failure diagnosis is prohibited when the vehicle is judged to be reversed from the result of advancing direction judgement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device capable of diagnosing a failure of a drive means for switching a shift stage of an automatic transmission for a vehicle.

[0002]

2. Description of the Related Art A shift lever for setting a shift stage of an automatic transmission for a vehicle has a predetermined vehicle forward range (for example, D range).
A control device for diagnosing the failure of the drive means for switching the shift speed has been conventionally known, and as an example of this, the engine speed at a certain shift speed is within a normal range determined by the vehicle speed at that time. There is one that diagnoses whether or not the drive means is out of order by checking whether or not it is outside.

Further, in this device, when the shift lever is set to the reverse range (R (reverse) range) and the vehicle moves backward, the gear shift does not occur. Therefore, failure diagnosis at this time is prohibited (erroneous diagnosis is prohibited). In addition, the failure diagnosis is prohibited based on the signal from the reverse range switch that is turned on when the shift lever is set to the reverse range.

[0004]

However, according to this prior art, when an abnormality occurs in the reverse range switch,
Although the reverse range switch is turned off despite the fact that the shift lever is actually set to the reverse range and the vehicle is moving backward, the control device does not set the shift lever to the reverse range, that is, the shift lever is set to the reverse range. There is a problem that a malfunction diagnosis is performed by erroneously determining that the predetermined forward range is set, and as a result, a false diagnosis is made that the drive unit of the gear stage is malfunctioning.

In view of the above problems, it is an object of the present invention to prevent erroneous gear stage malfunction diagnosis when the reverse range switch is abnormal.

[0006]

In order to achieve the above object, according to the invention of claim 1, when a shift lever for setting a shift stage of an automatic transmission for a vehicle is set to a predetermined vehicle forward range, Drive means (7,
In a control device for an automatic transmission for a vehicle, which performs the failure diagnosis of 8), a detection that outputs a rotating body (11) that rotates with the rotation of wheels and a series of detection signals that accompany the rotation of the rotating body (11). A vehicle speed sensor (1) including a section (12), wherein the pattern of the series of detection signals differs depending on the rotating direction of the rotating body (11); and the detection signal of the vehicle speed sensor (1). A traveling direction determination means (step 2) for determining the traveling direction of the vehicle based on the pattern.
02-208) and this traveling direction determination means (step 2
02-208), it is characterized by a control device for an automatic transmission for a vehicle configured to prohibit the failure diagnosis when it is determined that the vehicle is moving backward.

According to the second aspect of the invention, when the shift lever for setting the shift speed of the automatic transmission for a vehicle is set to a predetermined vehicle forward range, the drive means (7, 8) for switching the shift speed is broken. In a control device for an automatic transmission for a vehicle for diagnosing, a rotating body (11) rotating with the rotation of wheels, and a detecting section (12) outputting a series of detection signals accompanying the rotation of the rotating body (11). A vehicle speed sensor (1) configured such that the pattern of the series of detection signals differs depending on the rotation direction of the rotating body (11),
A reverse range switch (2b) that outputs a reverse range signal when the shift lever that sets the shift speed of the automatic transmission for a vehicle is set to the reverse range (R) of the vehicle, and the detection from the vehicle speed sensor (1). Based on the signal pattern,
A traveling direction determination means (steps 202 to 208) for determining the traveling direction of the vehicle, and the reverse range switch (2b).
Based on the reverse range signal from, the reverse range determining means (step 211) for determining whether the shift lever is in the reverse range (R) and the traveling direction determining means (steps 202 to 208). For a vehicle configured to prohibit the failure diagnosis when it is determined that the vehicle is moving backward and the shift lever is determined not to be in the reverse range (R) by the reverse range determining means (step 211). It features a control device for an automatic transmission.

According to a third aspect of the present invention, in the vehicle automatic transmission control device according to the first or second aspect, the rotating body (11) of the vehicle speed sensor (1) is made of a magnetic material, and On the outer circumference of the rotating body (11), convex portions (11a to 1a) having different lengths in the rotation direction are provided.
1d) or concave portions (11e to 11h) are alternately formed, and the detection portion (12) of the vehicle speed sensor (1) is provided so as to face the concave and convex portions (11a to 11h) and the concave and convex portions (11a). .About.11 h), the magnetic sensor is configured to output a signal according to a change in magnetic flux with rotation.

The reference numerals in parentheses of the above means indicate the correspondence with the concrete means of the embodiments described later.

[0010]

According to the control device for an automatic transmission for a vehicle according to the present invention, the traveling direction determining means determines the traveling direction of the vehicle based on the pattern of the detection signal from the vehicle speed sensor. Is surely done. Therefore, when the traveling direction determination means determines that the vehicle is moving backward, that is, by prohibiting the failure diagnosis when the vehicle is actually moving backward, the reverse range switch may be abnormal but normal. However, it is possible to prevent erroneous diagnosis of the failure of the drive means for switching the shift speed.

Further, in the present invention, since the traveling direction judging means is constructed to make the judgment based on the signal of the existing vehicle speed sensor, it is not necessary to provide a separate sensor for making the judgment. Further, according to the control device for an automatic transmission for a vehicle of claim 2, when the traveling direction determination means determines that the vehicle is moving backward, and the reverse range determination means determines that the shift lever is in the reverse range. That is, if an abnormality occurs in the reverse range switch, the failure diagnosis is prohibited. As a result, when the reverse range switch is abnormal, the failure diagnosis is prohibited when the vehicle is moving backward, so that it is possible to prevent erroneous failure diagnosis of the drive unit that switches the shift speed.

According to the third aspect of the present invention, since the recesses or protrusions formed on the outer circumference of the rotating body of the vehicle speed sensor have different lengths in the rotating direction of the rotating body, the recesses or protrusions face each other. The pattern of a series of detection signals (signals corresponding to changes in magnetic flux) output by the magnetic sensor (detection unit) that is provided as described above differs depending on the rotation direction of the rotating body. As described above, in the present invention, the pattern of the series of detection signals output from the detection unit can be made different depending on the rotating direction of the rotating body only by devising the shape of the rotating body as described above.

[0013]

Embodiments of the present invention will now be described with reference to FIGS. FIG. 1 shows the overall configuration of this embodiment. In FIG. 1, 1 is a vehicle speed sensor that detects the vehicle speed from the rotational speed of the wheels, 2 is a position switch that outputs a range signal according to the setting range of a shift lever (not shown) that sets the shift stage of the automatic transmission, 3 Is a throttle sensor that detects the amount of depression of the accelerator, 4 is a water temperature sensor that detects the engine cooling water temperature, 5 is an intake air temperature sensor that detects the intake air temperature, 6 is an intake pipe pressure sensor that detects the intake pipe pressure, and 13 is the engine It is an engine rotation speed sensor that detects the rotation speed. Further, 7 and 8 are solenoids that output the shift speed of the automatic transmission.

A transmission control unit 9 includes a waveform shaping circuit 9a for shaping the detection signal from the vehicle speed sensor 1, an input interface (I / F) 9b to which a signal from the position switch 2 is input, and each of the above sensors. A / D converter 9 for A / D converting signals from 3 to 6
c, ROM 9d, RAM 9e, and the above 9a to
Based on the signal from 9c, a predetermined calculation described later is performed,
This is a well-known one that includes a CPU 9h that controls a current supplied to the solenoids 7 and 8 via drive circuits 9f and 9g.

The vehicle speed sensor 1 includes a rotating body 11 made of a magnetic body which rotates with the rotation of wheels, and the rotating body 11.
And an electromagnetic pickup 12 that generates an AC voltage signal according to a change in magnetic flux due to rotation. A plurality of different lengths (in this embodiment, 4
Convex portions 11a to 11d are alternately formed, and thereby four concave portions 11e to 11h having different lengths are alternately formed. In addition, as the rotating body, N
A permanent magnet such as i, 13% Al-Fe, or Ni-Cu-Co ferrite is used.

A first unevenness composed of 11a and 11e,
The second unevenness made up of 11b and 11f, the third unevenness made up of 11c and 11g, and the fourth unevenness made up of 11d and 11h are formed at 90 ° intervals. 20% of the irregularities, the convex portions 11b occupy 40% of the second irregularities, the convex portions 11c occupy 60% of the third irregularities, and the convex portions 11d occupy 80% of the fourth irregularities. That is, the recessed portion 11e has 80% of the first unevenness, the recessed portion 11f has 60% of the second unevenness, the recessed portion 11g has 40% of the third unevenness, and the recessed portion 1
1 h occupies 20% of the fourth unevenness.

Then, a series of detection signals output from the pickup 12 in accordance with the rotation of each of the concave and convex portions is waveform-shaped by the waveform shaping circuit 9a and becomes a pulse voltage signal having a pattern as shown in FIG. . Here, FIG.
Nos. 1 to 4 are signals corresponding to the above-mentioned first to fourth irregularities, respectively. When this signal has a pattern of →→→→, it means that the vehicle is moving forward, and conversely →→→.
The pattern → is different from the previous pattern when the vehicle is moving backward.

The series of signals are input to the interrupt port of the CPU 9h, and the CPU 9h generates an interrupt at the rising or falling of the pulse signal and activates the interrupt processing. This interrupt processing will be described later with reference to FIG. The position switch 2 is a neutral switch 2a that is turned on to output a signal when the shift lever is set to the parking range (P) and the neutral range (N), and the shift lever is set to the reverse range (reverse range). The reverse range switch (hereinafter referred to as the R range SW) 2b that is turned on to output a signal, the second range switch 2c that is turned on to output a signal when the shift lever is set to the second range, and the shift lever are The low range switch 2d is turned on to output a signal when the low range is set.

Next, the basic shift processing in this embodiment will be described with reference to the flowchart of FIG. Here, FIG. 3A is a main routine of the shift process, and FIG.
Shows a subroutine showing the details of step 10 and step 40 in FIG. As shown in FIG. 3A, first, at step 10, the shift point is calculated with reference to the map at the time of upshift. Specifically, as shown in FIG. 3B, at step 11, a map of shift points is selected from the current shift stage. Then, in step 12, the shift point is calculated from the throttle opening detected by the throttle sensor 3.

Then, in step 20, it is determined whether or not the vehicle speed (SPD) detected by the vehicle speed sensor 3 crosses (exceeds) the shift point, and if it does, an upshift is executed in step 30. Therefore, the energizing currents of the solenoids 7 and 8 are controlled. If it does not cross, the shift point is calculated in step 40 with reference to the map at the time of downshift.

Specifically, in step 11 of FIG. 3B, a map of shift points is selected from the current shift stage, and in step 12, the shift point is calculated from the throttle opening. Then, in the next step 50, it is determined whether or not the SPD crosses (falls below) the shift point. If it is determined that the SPD has crossed, the downshift is executed in step 60. If it is determined that the crossing has not occurred, nothing is done. Exit to END.

Next, the interrupt processing will be described with reference to the flowchart of FIG. Note that FIG. 4 is a flowchart of an interrupt routine performed when the pulse signal (FIG. 2) rises or falls. First, at step 101, it is determined whether or not the interrupt processing this time is performed by the falling signal based on a switching flag described later. That is, the electromagnetic pickup 12 is the rotating body 1.
It is determined whether or not the passage of the falling edge falling from the convex portion 1 to the concave portion is detected. If NO is determined, that is, if the passage of the rising edge rising from the concave portion to the convex portion is detected, the present interrupt time T _OFF (n) is fetched and stored in the RAM 9e.

Then, in the next step 107, the switching flag is switched to terminate the interrupt processing. By thus switching the switching flag in step 107, the determination result in step 101 can be switched alternately for each interrupt process. That is, it is possible to determine YES when the electromagnetic pickup 12 detects the passage of the falling edge, and to determine NO when it detects the passage of the rising edge.

If YES is determined in step 101, the current interrupt time T _ON is determined in step 103.
(n) is fetched and stored in the RAM 9e. Then, in step 104, the pulse width tP (n) is calculated from the difference between the current interrupt time T _ON (n) and the previous interrupt time T _ON (n-1). Then, in step 105, the falling edge interrupt time T _ON (n) of this time and R in the previous step 102
Rising edge interrupt time T stored in AM9e
_The duty ratio tD (n) is calculated by dividing the difference from _OFF (n) by the pulse width tP (n).

Next, at step 106, P (n-3) ← P (n-
2), P (n-2) ← P (n-1), P (n-1) ← P (n), P (n) ←
Like tP (n), the latest 4 pulse widths are stored in the RAM 9e, and D (n-1) ← D (n), D (n) ← tD.
The latest two duty ratios are stored in the RAM 9e as shown in (n). Then, after the processing of step 107 is performed, the interrupt processing is ended.

Next, the abnormality determination processing of the R range SW2b will be described with reference to the flowchart of FIG. First, at step 201, the vehicle speed is calculated from the latest 4 pulse widths. Next, in steps 202 to 208,
Based on the latest 2 duty ratios D (n) and D (n-1),
By determining which of the latest two pulses is from (1) to (2) of FIG. 2, it is determined whether the vehicle is moving forward or backward.

Specifically, first, at step 202, D
It is determined whether (n) is 50% or more. If YES is determined in this step, the latest pulse (pulse having a duty ratio of D (n)) is any one of the following, and therefore the next step 20
This determination is made at 3. That is, in step 203, D
It is determined whether or not (n) is 70% or more. If YES is determined, NO is determined.

Similarly, when NO is determined in step 202, the latest pulse is any of the above, and therefore this determination is made in the next step 204. That is, in step 204, it is determined whether D (n) is 30% or more. If YES is determined, NO is determined. In this way, when it is determined in steps 202 to 204 which of the latest pulses is to, this time, in steps 205 to 208, the pulse (duty ratio one pulse before the latest pulse (duty ratio) is determined. Is a pulse of D (n-1)).

Specifically, for example, step 205
Then, it is determined whether D (n-1) is less than 30%.
Here, D (n) at this time is as described above, and as can be seen from FIG. 2, since the pulse one time before is either of the above, the pulse one time before is
If YES is determined in 05, NO is determined. Similarly, in steps 206 to 208 as well, it is determined which of the above-mentioned one-time pulse is.

As described above, by judging which of the above-mentioned latest two pulses is, it is possible to know whether the pattern of this pulse is a pattern of →→→→ or a pattern of →→→→. This makes it possible to determine whether the vehicle is moving forward or backward. If it is determined that the vehicle is moving backward according to this pattern, step 2
At 09, a traveling direction determination flag (described later) is set,
When it is determined that the vehicle is moving forward, the traveling direction determination flag is reset in step 210.

Then, in the next step 211, it is determined whether or not the R range SW2b is turned on based on the signal from the R range SW2b. If YES is determined, it is determined in step 212 whether the vehicle is moving backward based on the traveling direction determination flag. Conversely, N
Even when it is determined to be O, it is determined whether the vehicle is moving backward based on the traveling direction determination flag.

Then, if YES is determined in step 212 or NO is determined in step 216, the signal from the R range SW 2b and the above step 20.
Since there is no contradiction with the result of the vehicle traveling direction determination in 2 to step 208, the R range SW2b is considered to be normal, and the R range SW flag (described later) is set in step 213 to exit to END. .

On the other hand, if NO in step 212 or YES in step 216, there is a contradiction between the signal from the R range SW 2b and the result of the vehicle traveling direction determination. , R range SW2b is considered to be abnormal, the R range SW flag is reset in step 214, the R range flag WRL (described later) is set to 0 in step 215, and the process goes to END.

Next, the gear stage failure diagnosis processing of this embodiment will be described with reference to FIGS. 6 and 7. Here, in FIG.
Flowchart of failure diagnosis necessity determination performed every ms,
FIG. 7 is a flowchart of a failure diagnosis information storage process performed every 64 ms. First, step 501 to step 5
At 07, it is determined whether or not the normality of the solenoids 7 and 8 can be performed at step 524, which will be described later.
Thereafter, in step 509, it is determined whether or not the abnormality detection of the solenoids 7 and 8 may be performed in step 522, which will be described later, and further, steps 511 to 5 are performed.
At 18, it is determined whether or not it is a condition under which failure diagnosis of the solenoids 7 and 8 can be performed.

Specifically, at step 501, each flag (WNSW, WRL, X2L, XL) to be set to 1 when each of the position switches 2a to 2d is turned on.
By determining whether or not L) is all 0, it is determined whether or not the shift lever is set to the D range. Further, in step 502, it is determined whether or not the delay time CNDD after the neutral switch 2a is turned off is a predetermined time (for example, 2 seconds) or more.

In step 503, it is determined whether the engine cooling water temperature THW detected by the water temperature sensor 4 is within the normal range. In step 504, the EFI (not shown) connected to the CPU 9h via a communication path is connected. It is determined whether the CPU for the electronically controlled fuel injection device) is normal. In step 505, it is checked whether or not the solenoids 7 and 8 are broken or short-circuited. In step 506, the battery voltage supplied to the CPU 9h is checked. In step 507, the KCS advance learning value (AKG (RAM
Value)) is within the control range.

Then, the above steps 501 to 50
If it is determined to be all YES in step 7, it is considered that the above-described normality determination may be performed in step 523 (FIG. 7), and the normality determination flag is set in step 508.
Further, if even one of steps 501 to 507 is determined to be NO, it is regarded as a condition in which the above-mentioned normality determination cannot be performed, and the process directly goes to END without doing anything.

Then, in step 509, the intake air temperature sensor 5
It is checked whether the intake air temperature (THA) detected by is within the normal range, and if it is within the normal range, it is considered that the above abnormality detection may be performed in step 521 (FIG. 7), and in step 510. Set the abnormality detection flag.
If it is not within the normal range, it is regarded as a condition in which the above abnormality detection cannot be performed, and nothing is done, and the process directly goes to END.

Then, in steps 511 to 516, the number of revolutions of the vehicle speed sensor 1, the throttle opening detected by the throttle sensor 3, the intake pipe pressure (PM) detected by the intake pipe pressure sensor 6, the shift stage, after the shift output. Of the R range SW set in step 213 or step 214 in step 517, if the delay time and other related diagnostics (fault diagnosis) are not detected. Based on the flag, it is determined whether to proceed to step 518 or step 519. In addition, steps 511 to 516
If even one of them becomes NG, do nothing and exit to END.

If NO is determined in step 517, that is, if the R range SW2b is normal, the failure diagnosis flag is set in step 519, assuming that the failure diagnosis of the solenoids 7 and 8 may be performed. . See also YE
If it is determined to be S, that is, if the R range SW2b is abnormal, in step 518, the above steps 209 and 210 are performed.
Based on the traveling direction determination flag set in step 5, it is determined whether to proceed to step 519 or exit END without doing anything.

On the other hand, the failure diagnosis processing shown in the flowchart of FIG. 7 is performed every 64 ms. In this processing, first, in step 520, the failure diagnosis is performed based on the failure diagnosis flag set in step 519. Judge whether it is good or not, and if it is not good, do nothing and exit to END.
If it is determined that the failure diagnosis may be performed, in step 521, it is determined whether or not the abnormality detection of the solenoids 7 and 8 may be performed based on the abnormality detection flag set in step 510. .

If YES is determined in this step 521, that is, if it is a condition that both abnormality detection and normality determination can be performed, first, in step 522, the engine speed detected by the engine speed sensor 13 is within the abnormal range. Determine if there is. If it is determined to be abnormal, step 52
Go to 5. In this step 525, the number of times determined to be YES in step 522 is counted. If the number of times counted is less than 5, the process goes to END, and when it reaches 5, the solenoids 7 and 8 are abnormal in step 526. The abnormal flag indicating that is is set.

If NO in step 522, it is then determined in step 524 whether the engine speed is within the normal range. Then, if it is determined to be within the normal range, the process proceeds to step 525. In this step 525, the number of times determined to be YES in step 524 is counted, and if the number of times counted is less than 5, EN
When the routine goes to D and reaches 5 times, in step 526, the normality flag indicating that the solenoids 7 and 8 are normal is set. The normal flag and the abnormal flag are
The RAM 9e is set in a standby RAM area in which the stored contents are held even if the ignition switch is turned off.

On the other hand, if NO is determined in step 521, the process proceeds to step 523, and it is determined based on the normality determination flag set in step 508 whether or not the condition is normal. If YES is determined, the process proceeds to step 524, and if NO is determined, the process directly ends in END. It should be noted that each step in each of the flowcharts of FIGS. 3 to 7 described above constitutes means for realizing each function.

As described above in detail, in this embodiment, the convex portions 11a to 1a formed on the outer periphery of the rotating body 11 of the vehicle speed sensor 1 are used.
Since the lengths of the recesses 1e to 11h in the rotation direction are different from each other, the pattern of a series of signals detected by the electromagnetic pickup 12 can be changed depending on the rotation direction of the rotating body 11. Therefore, based on the pattern of this signal, step 202 to step 2
At 08, the traveling direction of the vehicle is determined. As a result of this determination, when the vehicle is moving backward, it is determined as NO at step 518 and step 519 is bypassed to prohibit the failure diagnosis of the solenoids 7 and 8. By step 5
It is possible to prevent erroneous determination in step 26.

Further, in this embodiment, the above steps 202-
When the vehicle traveling direction determined in step 208 and the on / off state of the R range SW2b determined in step 211 conflict, it is determined that the R range SW2b is abnormal, and it is determined YES in step 517. In step 518, if the vehicle is moving backward, it is determined to be NO in step 518 and the failure diagnosis is prohibited. Therefore,
When the R range SW2b is abnormal, it is possible to prevent the failure diagnosis from being erroneously performed even when the vehicle is moving backward.

When the R range SW2b is abnormal, the R range flag WRL may become 1 even though it is actually the D range. In this case, step 5
If NO is determined in 01, the problem that the failure diagnosis of the solenoids 7 and 8 is not performed in the D range is desired. Therefore, in this embodiment, in order to prevent the above problems,
When it is determined that the R range SW2b is abnormal, the R range flag WRL is forcibly set to 0 in step 215.

When the actual range is set to the R range and the vehicle is moving backward, it is judged in step 202 to step 208 that the vehicle is moving backward, and based on this judgment result, step 518 is executed. Therefore, the failure diagnosis is prohibited and the failure diagnosis is prohibited. (Other Embodiments) In the above embodiment, the shapes of the convex portions 11a to 11d and the concave portions 11e to 11h of the rotating body 11 of the vehicle speed sensor 1 are different from each other. Alternatively, the outer peripheral shape of the rotating body 11 may be a concave-convex shape with equal intervals. At this time, for example, a plurality of the electromagnetic pickups 12 are provided so as to be displaced in the rotation direction of the rotating body 11, and the rotation direction of the rotating body 11, that is, the traveling direction of the vehicle is determined based on the phase shift of the detection signals from the respective pickups 12. Configure so that it can be judged.

In step 526, when the solenoids 7 and 8 are diagnosed to be abnormal, the abnormality flag is set. Based on this abnormality flag, the vehicle occupant is notified via a predetermined notification means (for example, a lamp). You may notify that. Further, in the above-described embodiment, the vehicle speed sensor 1, the R range SW 2b, the traveling direction determination means as in steps 202 to 208, and step 211.
A means for determining whether or not the R range SW2b is turned on, that is, a backward range determining means for determining whether or not the R range is the R range based on a signal from the R range SW2b.

Therefore, if the traveling direction determining means determines that the vehicle is moving backward and the reverse range determining means determines that the shift lever is not in the R range, an abnormality in the R range SW2b can be detected. . Similarly, when the traveling direction determination means determines that the vehicle is moving forward and the reverse range determination means determines that the shift lever is in the R range, an abnormality in the R range SW2b can be detected. .

Further, in the above-mentioned embodiment, the detecting section is constituted by the electromagnetic pickup 12, but it may be constituted by the MRE (magnetoresistive element).

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

FIG. 2 is a pulse waveform diagram of a vehicle speed sensor signal after waveform shaping in the above embodiment.

FIG. 3A is a flowchart of a shift process of the above embodiment, and FIG. 3B is a flowchart showing details of step 10 and step 40 in FIG.

FIG. 4 is a flowchart showing an interrupt process of the above embodiment.

FIG. 5 is a flowchart of an abnormality determination process of the R range SW2b of the above embodiment.

FIG. 6 is a flow chart of determination of necessity of failure diagnosis according to the above-described embodiment.

FIG. 7 is a flowchart of a failure diagnosis process of the above embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vehicle speed sensor, 2 ... Position switch, 2b ... R range SW, 7, 8 ... Solenoid (transmission), 9 ... Control unit, 11 ... Rotating body, 11a-11d ... Convex part, 11e
~ 11h ... Recessed portion, 12 ... Electromagnetic pickup (detection portion)

Claims (3)

[Claims] 1. A control device for an automatic transmission for a vehicle, wherein when a shift lever for setting a shift speed of the automatic transmission for a vehicle is set to a predetermined vehicle forward range, a failure diagnosis of drive means for switching the shift speed is performed. A rotating body that rotates with the rotation of the wheels, and a detection unit that outputs a series of detection signals accompanying the rotation of the rotating body,
A vehicle speed sensor configured such that the pattern of the series of detection signals varies depending on the rotation direction of the rotating body, and a traveling direction determination unit that determines the traveling direction of the vehicle based on the pattern of the detection signals from the vehicle speed sensor. And a control device for an automatic transmission for a vehicle configured to prohibit the failure diagnosis when the traveling direction determination means determines that the vehicle is moving backward. 2. A control device for an automatic transmission for a vehicle, wherein when a shift lever for setting a shift speed of the automatic transmission for a vehicle is set in a predetermined vehicle forward range, a failure diagnosis of drive means for switching the shift speed is performed. A rotating body that rotates with the rotation of the wheels, and a detection unit that outputs a series of detection signals accompanying the rotation of the rotating body,
When the vehicle speed sensor is configured such that the pattern of the series of detection signals differs depending on the rotation direction of the rotating body, and the shift lever that sets the gear position of the automatic transmission for a vehicle is set to the vehicle reverse range, the reverse range is set. A reverse range switch that outputs a signal, based on the pattern of the detection signal from the vehicle speed sensor, a traveling direction determination unit that determines the traveling direction of the vehicle, and based on the reverse range signal from the reverse range switch, A reverse range determination means for determining whether or not the shift lever is in the reverse range, the forward direction determination means for determining that the vehicle is moving backward, and the reverse range determination means for determining that the shift lever is reverse When it is determined that the vehicle is not in the range, the automatic change for vehicle is configured so that the failure diagnosis is prohibited. Speed control device. 3. The vehicle speed sensor is configured such that a rotating body of the vehicle speed sensor is made of a magnetic material, and convex portions or concave portions having different lengths in the rotation direction are alternately formed on an outer periphery of the rotating body. 2. The detection unit of 1 is provided so as to face the convex portion or the concave portion, and is composed of a magnetic sensor that outputs a signal according to a change in magnetic flux due to the rotation of the convex portion or the concave portion. Alternatively, the control device for the automatic transmission for a vehicle according to the item 2.