JP3997394B2 - Control device for automatic transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for an automatic transmission that controls engagement / disengagement of a starting frictional engagement element that is engaged / disengaged when starting a vehicle.
[0002]
[Prior art]
Conventionally, a fluid transmission device that transmits the rotation of the engine to the transmission mechanism, a transmission mechanism that transmits the rotation of the engine via the fluid transmission device, and a plurality of friction engagement elements that switch gear stages of the transmission mechanism; In an automatic transmission having a hydraulic servo device that engages and disengages each friction engagement element by supplying and discharging an output hydraulic pressure corresponding to an electric signal applied to the solenoid valve, a solenoid is used to ensure a gear position as commanded. In addition to detecting electrical failures such as valve disconnection and short circuit, it is also possible to detect malfunctions caused by sticking of a valve body of a solenoid valve or biting of foreign matter. For example, when a command to switch to one gear stage is issued, even after the time necessary for engagement of the friction engagement elements to be engaged to establish the gear stage has elapsed, the vehicle speed or the transmission mechanism When the output rotational speed of the engine is less than a predetermined value and the input rotational speed to the transmission mechanism is detected to be greater than or equal to the predetermined value, it is determined that there is a neutral failure in which the transmission mechanism is fixed in the neutral state. A machine failure detection apparatus is described in Japanese Patent Application Laid-Open No. 11-280884.
[0003]
[Problems to be solved by the invention]
In the above-described conventional apparatus, since the detection of the neutral failure becomes accurate, it is effective in identifying the failure frictional engagement element. However, for example, when a command for engaging the starting clutch is sent out when the accelerator is stepped on at the time of starting, the valve body of the solenoid valve of the hydraulic servo device that engages and disengages the starting clutch sticks and the starting clutch When the hydraulic pressure is not supplied to the hydraulic drive unit, the engine speed increases, and in this state, the stick of the valve body of the solenoid valve is released, and if hydraulic pressure is supplied from the hydraulic servo device to the hydraulic drive unit of the clutch, the starting clutch The problem of sudden engagement and the occurrence of a large shock cannot be resolved.
[0004]
In view of such circumstances, an object of the present invention is to provide an automatic transmission that can prevent a sudden frictional engagement of a starting frictional engagement element and a large shock when a neutral failure occurs.
[0005]
[Means for Solving the Problems]
  In order to solve the above problems, the structural feature of the invention according to claim 1 is that a speed change mechanism to which rotation from an engine is input and a frictional engagement element for starting that is engaged when starting the vehicle. Output hydraulic pressure according to the electrical signal supplied to the solenoid valveIs supplied and dischargedIn a control device for an automatic transmission comprising a hydraulic servo device that engages and disengages a friction engagement element and an engine load detection device that detects a load state of the engine, the friction engagement element is engaged.A means for determining whether or not an output hydraulic pressure corresponding to the electrical signal is supplied despite the electrical signal being output to the solenoid valve, and the electrical signal being output to the solenoid valve, electoronic signalsWhen it is determined that the output hydraulic pressure corresponding to theThe engine load state detected by the engine load detection device isJudgment whether or not a predetermined high load stateMeans toIn the case of a predetermined high load state, The solenoid valve,Sends a command to release the frictional engagement elementMeans,It is to have.
  The structural feature of the invention according to claim 2 is that, when the engine load state detected by the engine load detection device is not a predetermined high load state, the friction engagement element is opened to the solenoid valve. It has a means for not sending a command.
[0006]
  Claim 3The structural features of the invention according to the present invention are as follows: a speed change mechanism in which the rotation of the engine is transmitted via a fluid transmission device; a starting friction engagement element that is engaged when starting the vehicle; and a solenoid valve Output hydraulic pressure according to the electrical signalIs supplied and dischargedIn a control device for an automatic transmission comprising a hydraulic servo device that engages and disengages a friction engagement element and an engine load detection device that detects a load state of the engine, the friction engagement element is engaged.A means for determining whether or not an output hydraulic pressure corresponding to the electrical signal is supplied despite the electrical signal being output to the solenoid valve, and the electrical signal being output to the solenoid valve, electoronic signalsWhen it is determined that the output hydraulic pressure corresponding to theThe engine load state detected by the engine load detecting means isJudgment whether or not it is in a predetermined high load stateMeans toIn the case of a predetermined high load state, The solenoid valve,Sends a command to release the frictional engagement elementAnd a load state of the engine detected by the engine load detecting device according to a command to release the friction engagement elementWhen the specified low load state is reached from the high load stateThe solenoid valve,Sends a command to engage the friction engagement elementMeans,It is to have.
[0007]
  Claim 4The structural features of the invention according toAny one of Claims 1 thru | or 3In the automatic transmission control device according to claim 1,The means for determining whether or not the output hydraulic pressure according to the electrical signal is supplied is selected when a traveling range is selected,An electrical signal to engage the frictional engagement elementDespite the output to the solenoid valve, the electric signalIt is to determine whether or not the output hydraulic pressure is supplied.
[0008]
  Claim 5The structural features of the invention according toAny one of Claims 1 thru | or 4In the automatic transmission control device according to claim 1,The means for determining whether or not the output hydraulic pressure corresponding to the electrical signal is supplied.An electrical signal for engaging the friction engagement element is selected when the travel range is selected from the state where the non-travel range is selected.Despite the output to the solenoid valve, the electric signalIt is to determine whether or not the output hydraulic pressure is supplied.
[0009]
  Claim 6The structural features of the invention according toAny one of Claim 1 thru | or 5In the control apparatus for an automatic transmission described in (1), the engine load detection device detects an engine load state by detecting an input side rotational speed of the friction engagement element.
[0010]
  Claim 7The structural features of the invention according toAny one of Claim 1 thru | or 5In the control apparatus for an automatic transmission described in (1), the engine load detecting device detects a load state of the engine by detecting a throttle opening.
[0011]
  Claim 8The structural features of the invention according toAny one of Claim 1 thru | or 7In the automatic transmission control device according to claim 1,The means for determining whether or not the output hydraulic pressure according to the electric signal is supplied isEngage the frictional engagement elementAn electrical signal was output to the solenoid valveAfter a predetermined timeAccording to the electrical signalOutput hydraulic pressure is suppliedNotIt is to determine whether or not.
[0012]
[Operation and effect of the invention]
  In the invention according to claim 1 configured as described above, when a command to engage the starting frictional engagement element is sent, the solenoid valve is actuated and the hydraulic servo device generates the output hydraulic pressure as the frictional engagement element. The hydraulic engagement part is fed and discharged to engage the friction engagement element. At this time, if the valve body of the solenoid valve sticks, for example, and the hydraulic servo device does not output the output hydraulic pressure and the friction engagement element for starting does not engage, the engine speed increases and the friction engagement element If the rotational speed of the input side becomes high and the stick of the solenoid valve disc is released and the hydraulic servo device supplies hydraulic pressure to the hydraulic drive unit of the friction engagement element, the friction engagement element is suddenly engaged. Although a big shock is generated, in the present invention,Despite outputting an electrical signal to the solenoid valve,Output hydraulic pressure is not suppliedsometimesWhen the engine is in a predetermined high load state,For startCommand to release the frictional engagement elementTo the solenoid valveSince the engine is delivered, it can be prevented that the starting frictional engagement element is suddenly engaged and a large shock is generated when the engine is in a high load state.
  In the invention according to claim 2 configured as described above, when the load state of the engine is not a predetermined high load state, a large shock is generated even if the frictional engagement element for starting is suddenly engaged. Therefore, a command to open the friction engagement element is not sent to the solenoid valve.
[0013]
  Configured as aboveClaim 3In this invention, when a command to engage the starting frictional engagement element is sent, the solenoid valve is activated and the hydraulic servo device supplies / discharges the output hydraulic pressure to / from the hydraulic drive unit of the frictional engagement element. Engage the frictional engagement elements. At this time, if the valve body of the solenoid valve sticks, for example, and the hydraulic servo device does not output the output hydraulic pressure and the friction engagement element for starting does not engage, the engine speed increases and the friction engagement element If the rotational speed of the input side becomes high and the stick of the solenoid valve disc is released and the hydraulic servo device supplies hydraulic pressure to the hydraulic drive unit of the friction engagement element, the friction engagement element is suddenly engaged. Although a big shock is generated, in the present invention,Despite outputting an electrical signal to the solenoid valve,Output hydraulic pressure is not suppliedsometimesWhen the engine is in a predetermined high load state,For startCommand to release the frictional engagement elementTo the solenoid valveA command to engage the frictional engagement element for starting when the high load state is changed to the predetermined low load state.To the solenoid valveSince it is delivered, it is possible to prevent a sudden frictional engagement of the starting frictional engagement element with a high input side rotational speed and to generate a large shock. When temporary troubles such as such are resolved, return to normal control is allowed.
[0014]
  Configured as aboveClaim 4In the invention according to the present invention, the driving range is selected and the electric power for engaging the starting frictional engagement element is selected.Judgment whether output hydraulic pressure corresponding to the electrical signal is not supplied even though an air signal is output to the solenoid valveThe solenoid valve of the hydraulic servo device that engages and disengages the starting frictional engagement element that causes the vehicle not to start even when the travel range is selected and the accelerator is stepped on. It is possible to respond quickly and accurately to the stick of the valve body.
[0015]
  Configured as aboveClaim 5In the invention according to the present invention, the travel range is selected from the state in which the non-travel range is selected, and the starting frictional engagement element is engaged.Although the electrical signal is output to the solenoid valve, the electrical signalOutput hydraulic pressure according toJudge whether or notBecause I tried toA hydraulic servo apparatus that engages / disengages a starting frictional engagement element that causes a situation in which the vehicle does not start even when the driving range is selected from the state in which the non-driving range is selected and the accelerator is depressed. It can respond quickly and accurately to the stick of the valve body of the solenoid valve.
[0016]
  Configured as aboveClaim 6In the invention according to the above, the load state of the engine can be detected with a simple configuration by detecting the input side rotational speed of the friction engagement element.
[0017]
  Configured as aboveClaim 7In the invention according to the above, by detecting the throttle opening, the load state of the engine can be accurately detected with a simple configuration.
[0018]
  Configured as aboveClaim 8In the invention according toSaidEngage the frictional engagement elementOutput electrical signal to the solenoid valveAfter a predetermined time has passedAccording to the electrical signalOutput hydraulic pressure is suppliedNotTherefore, it is possible to accurately determine whether or not a predetermined output hydraulic pressure is supplied.
[0019]
Embodiment
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a skeleton diagram showing an example of an automatic transmission 10 controlled by a control device for an automatic transmission according to the present invention. The automatic transmission 10 is a torque as a fluid transmission device in which an unillustrated engine is rotationally connected. The transmission 11 is composed of a forward 6-speed and a reverse 1-speed transmission mechanism 12 in which output rotations of the converter 11 and the torque converter 11 are transmitted to the input shaft 20. The torque converter 11 includes a pump impeller 13, a turbine runner 14, a stator 15, and a stator 15, a one-way clutch 17 that supports and supports the case 16 of the speed change mechanism 12 in only one direction, and an inner race of the one-way clutch 17 in the case 16. A stator shaft 18 to be fixed is provided. A lockup clutch 19 directly connects the pump impeller 13 and the turbine runner 14.
[0020]
A speed change planetary gear G that is a main part of the speed change mechanism 12 is of a double pinion type and directly meshes with the large and small diameter sun gears S2 and S3 and the large diameter sun gear S2 and meshes with the small diameter sun gear S3 via the pinion P3. The long pinion P2 and the carrier C2 (C3) for supporting the pinion P3 and the ring gear R2 (R3) engaged with the long pinion P2 and connected to the output shaft 21 are configured. The large-diameter sun gear S2 is connected to the first brake B-1, the carrier C2 (C3) is connected to the input shaft 20 via the second clutch C-2, and the one-way clutch F-1 supported by the case 16 And connected in parallel to the brake B-2.
[0021]
The speed reduction planetary gear G1 of the speed change mechanism 12 is a single pinion type, the ring gear R1 is connected to the input shaft 20, the sun gear S1 is fixed to the case 16 and receives a reaction force, and the pinion meshed with the ring gear R1 and the sun gear S1 is supported. The carrier C1 is connected to the small-diameter sun gear S3 via the first clutch C-1, and is also connected to the large-diameter sun gear S2 via the third clutch C3.
[0022]
The relationship between the engagement and release of each clutch, brake and one-way clutch of the automatic transmission 10 and each gear stage is as shown in the engagement table of FIG. In the engagement table, ◯ indicates engagement, no mark indicates release, and Δ indicates engagement only during engine braking. FIG. 3 is a velocity diagram showing the relationship between the shift speed achieved by engagement of each clutch, brake and one-way clutch, and the rotation speed ratio of each element of the planetary gears G and G1 at that time.
[0023]
As is apparent from FIGS. 2 and 3, the first speed (1st) is achieved by the engagement of the clutch C-1 and the automatic engagement of the one-way clutch F-1. The rotation of the carrier C1 whose rotation of the input shaft 20 has been decelerated by the reduction planetary gear G1 is input to the small-diameter sun gear S3 of the transmission planetary gear G by the clutch C-1, and the carrier C2 (C3) whose reverse rotation is prevented by the one-way clutch F-1. ) Receives the reaction force, and the ring gear R2 (R3) is decelerated and rotated at the maximum reduction ratio and output to the output shaft 21.
[0024]
The second speed (2nd) is achieved by engagement of the clutch C-1 and the brake B-1. The rotation of the carrier C1 in which the rotation of the input shaft 20 is decelerated by the reduction planetary gear G1 is input to the small-diameter sun gear S3 of the transmission planetary gear G via the clutch C-1, and the rotation is prevented by the engagement of the brake B-1. The diameter sun gear S2 receives the reaction force, and the ring gear R2 (R3) is decelerated to the second speed and output to the output shaft 21. The reduction ratio at this time is smaller than the first speed (1st) as shown in FIG.
[0025]
The third speed (3rd) is achieved by engagement of the clutch C-1 and the clutch C-3. The rotation of the input shaft 20 is decelerated by the speed reduction planetary gear G1, and the rotation of the carrier C1 is simultaneously input to the small diameter sun gear S3 and the large diameter sun gear S2 by the clutches C-1 and C-3. R2 (R3) is rotated at the same rotational speed as the carrier C1 and is output to the output shaft 21.
[0026]
The fourth speed (4th) is achieved by engagement of the clutch C-1 and the clutch C-2. The rotation of the input shaft 20 is directly input to the carrier C2 (C3) of the transmission planetary gear G by the clutch C-2, and the rotation of the carrier C1 decelerated by the reduction planetary gear G1 is shifted by the clutch C-1. Input to the sun gear S3 of the planetary gear G, the ring gear R2 (R3) is decelerated to an intermediate rotational speed between the input shaft 20 and the carrier C1 and output to the output shaft 21.
[0027]
The fifth speed (5th) is achieved by engagement of the clutch C-2 and the clutch C-3. The rotation of the input shaft 20 is directly input to the carrier C2 (C3) of the transmission planetary gear G by the clutch C-2, and the rotation of the input shaft 20 is reduced by the reduction planetary gear G1, and the rotation of the carrier C1 is the clutch C of the transmission planetary gear G. -3 is input to the sun gear S2, and the ring gear R2 (R3) is rotated to the fifth speed and output to the output shaft 21.
[0028]
The sixth speed (6th) is achieved by engagement of the clutch C-2 and the brake B-1. The rotation of the input shaft 20 is directly input to the carrier C2 (C3) of the transmission planetary gear G by the clutch C-2, and the sun gear S2 whose rotation is prevented by the engagement of the brake B-1 receives a reaction force, and the ring gear R2 ( R3) is rotated to the sixth speed and output to the output shaft 21.
[0029]
Reverse (R) is achieved by engagement of clutch C-3 and brake B-2. The rotation of the carrier C1 whose rotation of the input shaft 20 has been decelerated by the deceleration planetary G1 is input to the sun gear S2 of the transmission planetary gear G via the clutch C-3, and the rotation of the carrier C2 blocked by the engagement of the brake B-2. (C3) receives the reaction force, and the ring gear R2 (R3) is reversed and output to the output shaft 21.
[0030]
In the automatic transmission 10, the first clutch C-1 is a starting frictional engagement element that is engaged when the traveling range D is selected and the vehicle starts when moving forward. Here, the starting frictional engagement element is a concept including a clutch or a brake that is engaged when the travel range D for forward travel or the travel range R for reverse travel is selected. In addition, when the travel range is selected, the vehicle stops in the first speed state by the braking force of the brake, and when the neutral control is performed and the clutch C-1 is released, the second speed is selected from the first speed. Therefore, when the brake is released at the start, the brake B1 prevents the reverse rotation of the output shaft 21 even if a reverse force is applied to the vehicle on the uphill, so that the vehicle does not move backward, and the clutch C-1 Is engaged and the driving force is transmitted, the vehicle is switched to the first speed and the vehicle starts smoothly. When engine braking is required, the brake B-2 is engaged, the carrier C2 (C3) is prevented from rotating forward, and the rotation from the output shaft 21 is the sun gear S3, the clutch C-1, the deceleration planetary G1, the torque It is transmitted to the engine via the converter 11 and the engine brake is applied.
[0031]
Next, the hydraulic servo device 26 that outputs the output hydraulic pressure supplied to and discharged from the hydraulic drive unit of the clutch C-1 will be described with reference to FIG. 25 is a manual valve that is manually switched to neutral N (non-traveling range), parking P (non-traveling range), forward travel range D, and reverse travel range R by the driver operating the shift lever. The line pressure is supplied. When the manual valve 25 is shifted to the travel range D, the input of the amplifying valve 27 of the hydraulic servo device 26 that outputs the output hydraulic pressure supplied to the hydraulic drive unit of the clutch C-1 is input to the port D communicated with the port PL. The port 28 and the line pressure port 30 of the switching valve 29 are connected to each other. 31 is a solenoid modulator valve to which the line pressure from the oil pump is supplied via the pressure reducing valve. The output hydraulic pressure controlled to a predetermined pressure is the input port 33 of the linear solenoid pressure regulating valve 32 and the port of the switching valve 29 of the hydraulic servo device 26. 34. The linear solenoid pressure adjusting valve 32 operates in response to a control current that is a control signal supplied from a control device to be described later and moves the valve body 36 until it balances the spring force of the compression spring 37. The control hydraulic pressure that is controlled to a predetermined pressure flowing in from 33 is reduced, and a control hydraulic pressure that decreases as the control current from the control device increases is generated at the output port 38. The output port 38 of the linear solenoid pressure regulating valve 32 is connected to the control port 39 of the amplification valve 27 and is connected to the switching port 40 of the switching valve 29. The amplifying valve 27 is a compression spring 41 in which the axial force due to the control hydraulic pressure of the linear solenoid pressure regulating valve 32 that acts on the large-diameter end surface of the valve body 40 when the valve body 40 is supplied from the control port 39 acts on the small-diameter end surface of the valve body 40. The output hydraulic pressure Pc corresponding to the control hydraulic pressure of the linear solenoid pressure regulating valve 32 is output, which is moved to a position where the spring force of the motor and the axial force due to the feedback hydraulic pressure are balanced, and the line pressure supplied to the input port 28 decreases as the control current increases. Then, it is supplied from the output port 42 to the input port 43 of the switching valve 29. When the valve body 45 is shifted to the right half position in the drawing, the switching valve 29 connects the input port 43 to the output port 44 and supplies the output hydraulic pressure Pc from the amplification valve 27 to the hydraulic drive unit of the clutch C-1. When the valve body 45 is shifted to the left half position in the figure, the line pressure port 30 is connected to the output port 44, and the line pressure from the port D of the manual valve 25 is supplied to the hydraulic drive unit of the clutch C-1. The clutch C-1 is maintained in the engaged state by the line pressure.
[0032]
The control device for the automatic transmission will be described based on the block diagram shown in FIG. The control device 50 having a built-in CPU includes an engine-side rotation speed sensor 51 that detects an engine-side rotation speed Ne of the torque converter 11 to which the engine rotation is transmitted, and a rotation of the input shaft 20 to which the output rotation of the torque converter 11 is input. The input shaft rotational speed sensor 52 that detects the number Ni, the throttle opening sensor 53 that detects the accelerator depression amount Ss, the vehicle speed sensor 55 that detects the rotational speed Nv of the output shaft 21, and the manual valve 25 are shifted to the traveling range D. Each detection signal is input from a range position sensor 56 or the like that sends out a signal Dr indicating whether or not the control signal is executed, a control program is executed based on these detection signals, and a control current as a control signal is supplied to the linear solenoid of the hydraulic servo device 26. The pressure is output to the pressure regulating valve 32. Since the rotational speed Ni of the input shaft 20 is decelerated by the reduction planetary gear G1 and inputted from the carrier C1 to the clutch C-1, the rotational speed Ni of the input shaft 20 becomes the input side rotational speed of the clutch C-1.
[0033]
Next, the operation of the control device for the automatic transmission according to the present invention will be described with reference to the flowchart of the control program shown in FIG. When the manual valve 25 is shifted to the neutral N by the shift lever, the control device 50 sets the maximum control current Imax that makes the output oil pressure Pc 0 to release the clutch C-1, and the linear solenoid 35 of the hydraulic servo device 50. To supply. As a result, the valve body 36 of the linear solenoid pressure regulating valve 32 and the valve body 40 of the amplification valve 27 are shifted to the left half position in FIG. 4, and the output port 38 and the output port 42 are communicated with the tank so that the output hydraulic pressure Pc becomes zero. Become. In the switching valve 29, the control hydraulic pressure supplied from the pressure regulating valve 32 to the switching port 40 becomes zero, so that the sum of the control hydraulic pressure and the spring force of the compression spring 46 is a predetermined pressure supplied from the solenoid modulator valve 31 to the port 34. The valve body 45 is shifted to the right half position in the figure, the hydraulic drive part of the clutch C-1 is communicated with the tank, and the clutch C-1 is released. The driver shifts the manual valve 25 to the traveling range D, releases the brake pedal, and depresses the accelerator to start. When the control device 50 determines that the manual valve 25 has been shifted from the neutral N to the travel range D (step 61), the control device 50 performs ND control to engage the first clutch C-1 so that an engagement shock does not occur. Then, the first speed is established (step 62). That is, in order to quickly close the gap between the clutch plates of the first clutch C-1, the control current I supplied to the linear solenoid SLC-1 of the hydraulic servo device 26 for the first clutch C-1 is reduced in a pulse shape. After supplying the pulsed initial hydraulic pressure to the hydraulic drive section of the first clutch C-1, the hydraulic drive section is increased to a position where the control current is slightly increased and the first clutch C-1 starts to slip due to the contact of the clutch plate. The stroke pressure necessary to move the piston is supplied, then the control current I is gradually decreased to gradually increase the output hydraulic pressure Pc, and the first clutch C-1 is engaged so as not to generate a shock. Thereafter, the control current is reduced to 0, and the first clutch C-1 is maintained in the engaged state by the line pressure.
[0034]
However, when the valve bodies 36 and 40 of the linear solenoid pressure regulating valve 32 or the amplification valve 27 stick, even if the control current I is decreased, the control hydraulic pressure corresponding to the control current I is applied to the output port 38 of the linear solenoid pressure regulating valve 32. It is not generated, or the amplifying valve 27 does not supply the output hydraulic pressure Pc corresponding to the control current I to the clutch C-1 via the switching valve 29, so that the clutch C-1 is not engaged. In this case, after supplying the control current I to the linear solenoid 35, the control device 50 outputs an output corresponding to the control current I even if a predetermined time required to complete the engagement of the clutch C-1 elapses. It is detected that the hydraulic pressure is not supplied, and it is determined that the clutch C-1 is not engaged. If the engine-side rotational speed Ne increases when the clutch C-1 is not engaged, the rotational speed Ni of the input shaft 20 via the torque converter 11, that is, the input-side rotational speed of the clutch C-1 increases. In this state, when the stick of the valve body 36 or 40 is released and the hydraulic servo valve 26 outputs the output pressure Pc, the clutch C-1 is suddenly engaged and a large shock is generated.
[0035]
In the present embodiment, in order to prevent the occurrence of this large shock, when the control device 50 completes the ND control (step 63), the automatic transmission 10 operates at the first speed (1st), the second speed (2nd), or the second speed. It is determined whether or not it is in the third speed (3rd) state (step 64). The first speed is selected when starting in the normal automatic shift mode, but the second speed or the third speed may be selected when starting on a low μ road in the manual shift mode. It is determined whether the speed is one of the third speed. If it is at any gear, it is determined whether or not the output hydraulic pressure Pc corresponding to the command to engage the first clutch C-1 is supplied from the hydraulic servo device 26 to the hydraulic drive unit of the clutch C-1. (Step 65). That is, after the time required for engagement of the clutch C-1 has elapsed and ND control has been completed, when the rotational speed Nv of the output shaft 21 of the transmission mechanism 12 is equal to or less than a certain value, the input side of the clutch C-1 It is checked whether or not the rotational speed Ni of the input shaft 20 that is the rotational speed is equal to or greater than a threshold value set for each of the first to third speeds. If it is equal to or greater than the threshold value, it is determined that the output hydraulic pressure Pc corresponding to the command to engage the first clutch C-1 is not supplied to the hydraulic drive unit of the clutch C-1, and the clutch C-1 is not engaged. The If the output hydraulic pressure Pc is being supplied, the program ends (step 71).
[0036]
When the output hydraulic pressure Pc is not supplied, whether the rotational speed Ni of the input shaft 20 detected by the input shaft rotational speed sensor 52 functioning as an engine load detecting device that detects the load state of the engine is equal to or greater than a predetermined value A Determination is made (step 66). The predetermined value A is a value set to determine the high load state of the engine, and is a value that cannot be detected if the clutch C-1 is normally engaged. For example, the value may be set so that the driver can experience the engine blow-up, or the gear ratio when the rotational speed Ni of the input shaft 20 is normal, such as the rotational speed Nv × gear ratio + α of the output shaft 21. You may set to the value when it deviates from the predetermined value more than. If it is greater than or equal to the predetermined value A, it is determined that the engine is in a predetermined high load state, the current applied to the linear solenoid 35 of the linear solenoid pressure regulating valve 32 is maximized, and the output hydraulic pressure Pc of the hydraulic servo device 26 is set to zero. The clutch C-1 is released, and the timer T starts counting (steps 67 and 68). Thus, in the state where the input side rotational speed of the clutch C-1 is higher than the predetermined value A, the sticks of the valve bodies 36 and 40 of the linear solenoid pressure regulating valve 32 or the amplification valve 27 are released, and the hydraulic servo valve 26 is moved to the clutch C. The output pressure Pc is output to the −1 hydraulic drive unit, and it is possible to prevent the clutch C-1 from being suddenly engaged and generating a large shock. The throttle opening sensor 53 may be an engine load detection device that detects the engine load state, and when the accelerator depression amount Ss is equal to or greater than a predetermined amount, it may be determined that the engine is in a predetermined high load state. .
[0037]
  Then, if the engine-side rotational speed Ne is high but the vehicle does not start for a while, the driver releases the accelerator, and the engine-side rotational speed Ne decreases. Thus, when it is determined that the rotational speed Ni of the input shaft 20 has become equal to or less than the predetermined value A (step 69), a command to engage the clutch C-1 is sent (step 70), and the clutch C-1 The control current I supplied to the linear solenoid SLC-1 of the hydraulic servo device 26 is controlled as described above to supply the output hydraulic pressure Pc to the hydraulic drive unit of the first clutch C-1, and the first clutch C-1 Engage so that shock does not occur. Thereafter, the control current is reduced to 0, the first clutch C-1 is maintained in the engaged state by the line pressure, and the control program is terminated (step 71). Even if the set time TO of the timer T elapses (step 72), if the rotational speed Ni of the input shaft 20 does not become a predetermined value or less, processing such as switching to the failure mode and turning on the abnormal lamp is performed (step 73). ). Step66When the rotational speed Ni of the input shaft 20 is determined to be equal to or less than the predetermined value A, a command to engage the clutch C-1 is sent (step70) End the control program. In Steps 69 and 70, when it is determined that the rotational speed Ni of the input shaft 20 has become equal to or less than the predetermined value A, a command to engage the clutch C-1 is sent. In order to prevent the clutch C-1 from being released in steps 66 and 67 and causing hunting when the rotational speed Ni exceeds a predetermined value, the clutch C-1 is detected when the rotational speed Ni becomes A-β in step 69. Hysteresis may be provided so as to engage.
[0038]
By controlling as described above, the stick suddenly disappears in a situation where the starting clutch is not engaged by the solenoid valve stick and the engine is blown up by the accelerator operation even though the driver has entered the driving range D. Even when the clutch C-1 is engaged, it can be prevented that the clutch C-1 is suddenly engaged and a large shock is generated.
[0039]
In addition to the case of starting at any one of the first to third speeds, the clutch C-1 for starting after switching, such as 5-3 shift (shift from 5th speed to 3rd speed), 6-2 shift, etc. Is engaged, the stick of the valve body 36, 40 of the linear solenoid pressure regulating valve 32 or the amplification valve 27 is released while the rotational speed Ni of the input shaft 20, that is, the input rotational speed of the clutch C-1 is high. Then, the output pressure Pc is output from the hydraulic servo valve 26 to the hydraulic drive unit of the clutch C-1, and the clutch C-1 may be suddenly engaged to generate a large shock. Also, start before and after switching, such as 1-2, 2-1, 1-3, 3-1, 2-3, 3-2, 2-4, 4-2, 3-4, 4-3 speed change. Even when the clutch C-1 is engaged, the control hydraulic pressure corresponding to the control current I is not already generated at the output port 38 of the linear solenoid pressure regulating valve 32 by the stick of the valve body 36 or the like before switching. When the output hydraulic pressure Pc is not supplied to the hydraulic drive unit of the clutch C-1 and the clutch C-1 is not engaged, the stick of the valve body 36 is released by a new switching command, and the hydraulic servo valve 26 releases the clutch. The output pressure Pc is output to the hydraulic drive unit of C-1, and the clutch C-1 may be suddenly engaged to generate a large shock. In order to prevent the occurrence of a large shock in the case of these specific shifts, in step 64, in addition to determining whether or not the speed is the first to third speeds, it is also determined whether or not these are specific shifts. May be. Since there is a vehicle speed during shifting, it is determined whether or not the output hydraulic pressure Pc corresponding to the command to engage the first clutch C-1 is supplied from the hydraulic servo device 26 to the hydraulic drive unit of the clutch C-1. In addition, after the time required for the engagement of the clutch C-1 has elapsed and the shift control is completed, the rotational speed Ni of the input shaft 20 of the transmission mechanism 12 is changed to the rotational speed Nv of the output shaft 21 after the shift. It is checked whether or not the value obtained by adding a predetermined value to the value obtained by multiplying the gear ratio is equal to or greater than the threshold value. It may be determined that the clutch C-1 is not engaged without being supplied to the hydraulic drive unit of C-1.
[0040]
In the above embodiment, the case where the forward travel range D is selected from the neutral N has been described. However, the forward travel range D from the parking P, the reverse travel range R from the neutral N, the reverse travel range R from the parking P, or the reverse travel. The present invention can be applied when the forward travel range D is selected from the range R or the reverse travel range R is selected from the forward travel range D. Among them, when the travel range is selected from the non-travel range, it can be applied particularly effectively, and even when the stick of the valve element 36 suddenly returns as described above when starting from the stop state, It is possible to prevent the occurrence of shock due to the sudden engagement of the coupling element.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram of an automatic transmission controlled by a control device for an automatic transmission according to the present invention.
FIG. 2 is an engagement table of clutches and brakes at each gear position of the automatic transmission.
FIG. 3 is a speed diagram showing a rotation speed ratio of each element of the planetary gear at each speed stage of the automatic transmission.
FIG. 4 is a diagram showing a hydraulic servo device that engages and disengages a clutch C-1.
FIG. 5 is a block diagram showing a control device for an automatic transmission.
FIG. 6 is a flowchart of a control program.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Automatic transmission, 11 ... Torque converter (fluid transmission device), 12 ... Transmission mechanism, 20 ... Input shaft, 21 ... Output shaft, 25 ... Manual valve, 26. ..Hydraulic servo device, 27 ... amplification valve, 29 ... switching valve, 32 ... linear solenoid pressure regulating valve, 35 ... linear solenoid, 36, 40 ... valve, 50 ... control Device: 51 ... Engine side rotational speed sensor, 52 ... Input shaft rotational speed sensor, 53 ... Throttle opening sensor, 55 ... Vehicle speed sensor, 56 ... Range position sensor, C-1 ..First clutch (starting friction engagement element)

Claims (8)

A speed change mechanism to which rotation from the engine is input, a friction engagement element for starting that is engaged when starting the vehicle, and an output hydraulic pressure corresponding to an electric signal supplied to the solenoid valve is supplied and discharged, and the friction In a control device for an automatic transmission comprising a hydraulic servo device that engages and disengages an engagement element and an engine load detection device that detects a load state of the engine,
Means for determining whether or not an output hydraulic pressure corresponding to the electric signal is supplied despite the fact that an electric signal for engaging the friction engagement element is output to the solenoid valve;
When it is determined that the output hydraulic pressure corresponding to the electrical signal is not supplied despite the electrical signal being output to the solenoid valve, the engine load state detected by the engine load detection device is a predetermined high load. means for determining whether a state,
A control device for an automatic transmission , comprising: means for sending a command to release the friction engagement element to the solenoid valve in a predetermined high load state. The engine has a means for not sending a command to open the friction engagement element to the solenoid valve when the engine load state detected by the engine load detection device is not a predetermined high load state. Item 2. The automatic transmission control device according to Item 1. A transmission mechanism to which the rotation of the engine is transmitted via a fluid coupling, a friction engagement element for starting to be engaged when starting the vehicle, the output hydraulic pressure corresponding to the electrical signal supplied to the solenoid valve In a control device for an automatic transmission, comprising: a hydraulic servo device that feeds and discharges the friction engagement element; and an engine load detection device that detects an engine load state
Means for determining whether or not an output hydraulic pressure corresponding to the electric signal is supplied despite the fact that an electric signal for engaging the friction engagement element is output to the solenoid valve;
When it is determined that the output hydraulic pressure corresponding to the electrical signal is not supplied despite the electrical signal being output to the solenoid valve, the engine load state detected by the engine load detecting means is a predetermined high load. means for determining whether a state,
Means for sending a command to release the frictional engagement element to the solenoid valve in the case of a predetermined high load state ;
When the engine load state detected by the engine load detection device changes from a high load state to a predetermined low load state in response to a command to release the friction engagement element, the friction engagement is applied to the solenoid valve. Means for sending a command to engage the element ;
A control device for an automatic transmission, comprising: The means for determining whether or not the output hydraulic pressure according to the electric signal is supplied is selected even when the traveling range is selected and the electric signal for engaging the friction engagement element is output to the solenoid valve. 4. The control apparatus for an automatic transmission according to claim 1 , wherein it is determined whether or not an output hydraulic pressure corresponding to the electric signal is supplied. Means for outputting hydraulic pressure corresponding to the electrical signal to determine whether or not supplied, driving range from a state in which the non-driving range is selected is selected, the electrical signal that engages the friction engagement element 5. The automatic transmission control according to claim 1 , wherein it is determined whether or not an output hydraulic pressure corresponding to the electrical signal is supplied in spite of the output to the solenoid valve. 6. apparatus. 6. The automatic shift according to claim 1, wherein the engine load detection device detects an engine load state by detecting an input side rotational speed of the friction engagement element. 7. Machine control device. 6. The control device for an automatic transmission according to claim 1, wherein the engine load detection device detects a load state of the engine by detecting a throttle opening. Means for outputting hydraulic pressure corresponding to the electrical signal to determine whether or not supplied, after outputting an electrical signal to engage the frictional engagement element to the solenoid valve, corresponding to the electric signal after a predetermined time has elapsed The control apparatus for an automatic transmission according to any one of claims 1 to 7, wherein it is determined whether or not the output hydraulic pressure is not supplied.

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