JP4972566B2 - Control method and control apparatus for automatic transmission - Google Patents

Description

  The present invention relates to an automatic transmission control method and control apparatus suitable for controlling an automatic transmission used in an automobile.

  An automated manual transmission (hereinafter referred to as “automatic MT”) is a system that automates the operation of a clutch, which is a friction mechanism, and the operation of a synchronous meshing mechanism, which is a gear selection mechanism, using a gear-type transmission used in a manual transmission. Have been developed).

  However, in the control at the time of shifting in the conventional automatic MT (automated manual transmission), the driving torque is interrupted by the release / engagement operation of the clutch, which may give the passenger an uncomfortable feeling.

  In order to avoid such a sense of incongruity due to torque interruption during shifting, two friction transmission mechanisms (clutches) for transmitting input torque to the transmission are disclosed in Japanese Patent Laid-Open Nos. 2000-234654 and 2001-295898. A twin-clutch type automatic MT is known in which drive torque is transmitted alternately by two clutches. In this twin clutch type automatic MT, when shifting is started, the clutch of the next shift stage is gradually engaged while gradually releasing the clutch that was transmitting torque before shifting, and the driving torque is then shifted before shifting. By changing from the gear ratio equivalent to the gear ratio after shifting, the driving torque can be interrupted and smooth shifting can be performed. The twin clutch type automatic MT may be configured using a dry clutch or a wet clutch.

  Further, Japanese Patent No. 3524161 and Japanese Patent No. 3246791 disclose techniques for estimating engine torque and torque converter torque and controlling the automatic transmission based on the estimated torque.

  In addition, an automatic transmission means for automatically setting the gear position based on the driving state and a manual transmission means for setting the gear position selected by manual operation are provided, and the engine speed is set in advance during manual gear shift selection. Japanese Patent No. 3600382 discloses a technique for preventing engine overspeed by performing an upshift when the overspeed determination value is exceeded.

JP 2000-234654 A JP 2001-295898 A Japanese Patent No. 3524161 Japanese Patent No. 3246791 Japanese Patent No. 3600382

  In such an automatic transmission, when manual shift is selected, when the upshift is executed when the engine speed exceeds a preset overspeed determination value, the upshift is prolonged for some reason, and the engine control device Therefore, there has been a problem that a shift shock occurs when the fuel supply of the engine is cut off to prevent engine overspeed.

  An object of the present invention is to provide a control method and a control device for suppressing a shift shock and obtaining a desired shift feeling even when fuel supply for preventing over-rotation is interrupted by an engine control device during an upshift. Is to propose.

  In the present invention, an automatic transmission including a first friction transmission mechanism and a second friction transmission mechanism that perform transmission and interruption of torque generated by an engine to an output shaft by adjusting a pressing load on a friction surface. After the upshift is started, the first friction transmission mechanism is released at a predetermined release speed, and a torque phase for engaging the second friction transmission mechanism at a predetermined engagement speed is executed. Automatic shift for executing an inertia phase for shifting the engine speed from the speed before the shift to the speed after the shift in a predetermined shift time by controlling the generated torque and the transmission torque of the second friction transmission mechanism In the machine control method, when the engine fuel injection is cut off in the torque phase, the first friction transmission mechanism is separated from the predetermined release speed at a faster release speed. Accordingly released, a second frictional transmission mechanism the control method of an automatic transmission to continue the engagement control, as well as a control device for executing this control method.

  According to the present invention, when the fuel injection of the engine is cut off, the first friction transmission mechanism is released according to a faster release speed different from the predetermined release speed, and the second friction transmission mechanism is fastened. By continuing the control, the shift shock can be suppressed and the desired shift feeling can be obtained even when the fuel supply for preventing over-rotation is cut off by the engine control device during the upshift.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.

  First, referring to FIG. 1, a first configuration example showing an embodiment of a shift control method for an automobile according to the present invention will be described.

  FIG. 1 is a first system configuration diagram showing an embodiment of a shift control method for an automobile according to the present invention.

  Engine 7 as a driving force source, an engine speed sensor (not shown) for measuring the number of revolutions of the engine 7, an electronically controlled throttle (not shown) for adjusting the engine torque, and a fuel amount corresponding to the intake air amount A fuel injection device (not shown) and an ignition device (not shown) are provided, and the engine control unit 101 manipulates the intake air amount, the fuel amount, the ignition timing, and the like, so that the torque of the engine 7 can be accurately controlled. It can be controlled. The fuel injection device includes an intake port injection method in which fuel is injected into an intake port or an in-cylinder injection method in which fuel is directly injected into a cylinder. However, an operating range (engine torque and engine speed) required for an engine is known. It is advantageous to use an engine of a system that can reduce fuel consumption and has good exhaust performance. As a driving force source, not only a gasoline engine but also a diesel engine or a natural gas engine may be used.

  The automatic transmission 50 includes a first clutch 8, a second clutch 9, and a first input shaft 41, which are friction transmission mechanisms that transmit or cut off the power of the driving force source by adjusting the pressing load on the friction surface. , Second input shaft 42, output shaft 43, first drive gear 1, second drive gear 2, third drive gear 3, fourth drive gear 4, fifth drive gear 5, reverse drive gear (not shown), 1 driven gear 11, 2nd driven gear 12, 3rd driven gear 13, 4th driven gear 14, 5th driven gear 15, reverse drive gear (not shown), 1st synchronous mesh mechanism 21, 2nd synchronous mesh A mechanism 22, a third synchronous meshing mechanism 23, a rotation sensor 31, a rotation sensor 32, and a rotation sensor 33 are provided, and the torque of the engine 7 is obtained by engaging and releasing the first clutch 8. Transmitted to the first input shaft 41, it is possible to cut off. The torque of the engine 7 can be transmitted to and cut off from the second input shaft 42 by engaging and releasing the second clutch 9. In the present embodiment, the first clutch 8 and the second clutch 9 are dry single plate clutches.

  The second input shaft 42 is hollow, and the first input shaft 41 passes through the hollow portion of the second input shaft 42 and can be moved relative to the second input shaft 42 in the rotational direction. ing.

  The first drive gear 1, the third drive gear 3, the fifth drive gear 5, and the reverse drive gear (not shown) are fixed to the second input shaft 42, and the second input shaft 42 rotates with respect to the first input shaft 1241. It is free. Further, the second drive gear 2 and the fourth drive gear 4 are fixed to the first input shaft 41, and the second input shaft 42 is configured to be capable of relative movement in the rotational direction. Yes.

  A sensor 31 is provided as means for detecting the rotational speed of the first input shaft 41, and a sensor 32 is provided as means for detecting the rotational speed of the second input shaft 42.

  On the other hand, the output shaft 43 is provided with a first driven gear 11, a second driven gear 12, a third driven gear 13, a fourth driven gear 14, a fifth driven gear 15, and a reverse driven gear (not shown). . The first driven gear 11, the second driven gear 12, the third driven gear 13, the fourth driven gear 14, the fifth driven gear 15, and the reverse driven gear (not shown) are provided rotatably with respect to the output shaft 43. Yes.

  A sensor 33 is provided as means for detecting the rotation speed of the output shaft 43.

  Among these gears, the first drive gear 1, the first driven gear 11, the second drive gear 2, and the second driven gear 12 are engaged with each other. The third drive gear 3 and the third driven gear 13 are engaged with the fourth drive gear 4 and the fourth driven gear 14, respectively. Further, the fifth drive gear 5 and the fifth driven gear 15 are engaged with each other. Further, the reverse drive gear (not shown), the idler gear (not shown), and the reverse driven gear (not shown) are engaged with each other.

  Further, between the first driven gear 11 and the third driven gear 13, the first synchronous gear 11 is engaged with the output shaft 43, or the third driven gear 13 is engaged with the output shaft 43. A meshing mechanism 21 is provided.

  Further, between the second driven gear 12 and the fourth driven gear 14, the third drive gear 12 is engaged with the output shaft 43, or the fourth driven gear 14 is engaged with the output shaft 43. A meshing mechanism 23 is provided.

  Further, the fifth driven gear 15 is provided with a second synchronous meshing mechanism 22 that engages the fifth driven gear 15 with the output shaft 43.

  By controlling the current of a first shift motor (not shown), which is an electric motor provided in the shift actuator 63, by the transmission control unit 100, the first synchronous meshing mechanism via a shift fork (not shown). By controlling the position or load of 21 and engaging with the first driven gear 11 or the third driven gear 13, the rotational torque of the second input shaft 42 is output via the first synchronous meshing mechanism 21 to the output shaft. 43 can be transmitted.

  Further, the transmission control unit 100 controls the current of a second shift motor (not shown), which is an electric motor provided in the shift actuator 64, so that the second synchronous meshing is performed via a shift fork (not shown). By controlling the position or load of the mechanical mechanism 22 and engaging with the fifth driven gear 15, the rotational torque of the second input shaft 42 is transmitted to the output shaft 43 via the second synchronous meshing mechanism 22. be able to.

  Further, the transmission control unit 100 controls the current of a third shift motor (not shown), which is an electric motor provided in the shift actuator 65, so that the third synchronous meshing is performed via a shift fork (not shown). By controlling the position or load of the mechanism 23 and engaging with the second driven gear 12 or the fourth driven gear 14, the rotational torque of the first input shaft 41 is transmitted via the third synchronous mesh mechanism 23. Can be transmitted to the output shaft 43.

  Thus, from the first drive gear 1, the second drive gear 2, the third drive gear 3, the fourth drive gear 4, and the fifth drive gear 5, the first driven gear 11, the second driven gear 12, and the third driven gear. 13, the rotational torque of the transmission input shaft 41 transmitted to the transmission output shaft 43 via the fourth driven gear 14 and the fifth driven gear 15 is a differential gear (not shown) connected to the transmission output shaft 43. To the axle (not shown).

  In addition, the transmission control unit 100 controls the current of a first clutch motor (not shown) that is an electric motor provided in the first clutch actuator 61, so that the pressure plate provided in the first clutch 8. (Not shown) is controlled to control the transmission torque of the first clutch 8.

  In addition, the transmission control unit 100 controls the current of a second clutch motor (not shown) that is an electric motor provided in the second clutch actuator 62, thereby providing a pressure plate provided in the second clutch 9. (Not shown) is controlled to control the transmission torque of the second clutch 9.

  Here, for example, in shifting from the first speed state to the second speed state, the first driven gear 11 and the output shaft 43 are engaged by the first synchronous meshing mechanism 21, and the second driven gear 12 and the output shaft 43 are connected to the third gear. The first clutch actuator 61 and the second clutch actuator 62 are controlled from the state in which the second clutch 9 is engaged and the first clutch 8 is released, and the second clutch 9 is gradually moved. This is done by gradually engaging the first clutch 8 while releasing.

  In this embodiment, the first clutch 8 and the second clutch 9 are operated as an electric operation mechanism using an electric motor. However, the clutch is operated using an electromagnetic hydraulic valve, a hydraulic cylinder, or the like. Alternatively, the clutch pressure plate may be controlled by an electromagnetic coil, or another mechanism for controlling the first clutch 8 and the second clutch 9 may be used.

  The first clutch 8 and the second clutch 9 are configured as dry clutches in this embodiment, but may be configured as wet multi-plate clutches.

  From the lever device 106, shift lever positions such as P range, R range, N range, D range (automatic shift mode), M range (manual shift mode), and ranges indicating manual shift upshift operation and downshift operation. A position signal is input to the transmission control unit 100.

  The transmission control unit 100 and the engine control unit 101 transmit / receive information to / from each other by communication means 103.

  FIG. 2 shows the input / output signal relationship between the transmission control unit 100 and the engine control unit 101. The transmission control unit 100 is configured as a control unit including an input unit 100i, an output unit 100o, and a computer 100c. Similarly, the engine control unit 101 is also configured as a control unit including an input unit 101i, an output unit 101o, and a computer 101c. An engine torque command value TTe is transmitted from the transmission control unit 100 to the engine control unit 101 using the communication means 103, and the engine control unit 101 realizes the TTe so that the intake air amount, fuel amount, Control ignition timing and the like (not shown). The engine control unit 101 includes engine torque detection means (not shown) that serves as input torque to the transmission. The engine control unit 101 rotates the engine speed Ne and the engine torque generated by the engine 7. Te is detected and transmitted to the transmission control unit 100 using the communication means 103. As the engine torque detecting means, a torque sensor may be used, or an estimating means based on engine parameters such as the injection pulse width of the injector, the pressure in the intake pipe and the engine speed may be used. Further, the engine control unit 101 is provided with a fuel supply cut-off means for cutting off the fuel supply to prevent over-rotation, and transmits a fuel cut signal Fcut to the transmission control unit 100 using the communication means 103. . Furthermore, an expected output torque estimating means for estimating an expected output torque when the torque reduction for shifting or the fuel supply for preventing over-rotation is not cut off is provided. The expected output torque VTe is transmitted to the machine control unit 100. Here, the expected output torque is calculated by calculating the basic torque generated by the engine from the injection pulse width of the injector, the pressure in the intake pipe, the amount of intake air, and the engine speed, and the friction torque from the water temperature and the signals of the auxiliary devices. Is calculated by subtracting the friction torque from the basic torque. The estimated output torque is preferably estimated without using the fuel amount and the ignition timing in order to estimate the torque value when the torque reduction for shifting and the fuel supply for preventing over-rotation are not shut off.

  Further, the transmission control unit 100 receives the first input shaft rotation speed NiA, the second input shaft rotation speed NiB, and the output shaft rotation speed No from the rotation sensor 31, the rotation sensor 32, and the rotation sensor 33, respectively. In addition, the lever device 106 shows shift lever positions such as P range, R range, N range, D range (automatic shift mode), M range (manual shift mode), and manual shift upshift operation and downshift operation. The range position signal RngPos is inputted, the accelerator pedal depression amount Aps is inputted from the accelerator opening sensor 201, and the ON / OFF signal Brk from the brake switch 202 for detecting whether or not the brake is depressed is inputted.

  Further, the lubricant temperature TEMPlub is input to the transmission control unit 100 from an oil temperature sensor 203 that measures the temperature of the lubricant within the transmission 50.

  Further, the transmission control unit 100 includes a first clutch 8 and a second clutch provided from the first clutch position sensor 61a and the second clutch position sensor 62a provided in the first clutch actuator 61 and the second clutch actuator 62, respectively. A first clutch position RPcl1 and a second clutch position RPcl2 indicating 9 strokes are input.

  Further, the transmission control unit 100 includes a first synchronous mesh from a sleeve 1 position sensor 63a, a sleeve 2 position sensor 64a, and a sleeve 3 position sensor 65a provided in the shift actuator 63, the shift actuator 64, and the shift actuator 65, respectively. The sleeve 1 position RPslv1, the sleeve 2 position RPslv2, and the sleeve 3 position RPslv3, which indicate the stroke positions of the mechanism 21, the second synchronization meshing mechanism 22, and the third synchronization meshing mechanism 23, are input.

  For example, when the driver depresses the accelerator pedal with the shift range set to the D range or the like, the transmission control unit 100 determines that the driver is willing to start and accelerate, and the driver depresses the brake pedal. When it is retracted, it is determined that the driver intends to decelerate and stop, and the engine torque command value TTe, the first clutch target transmission torque TTcl1, the second clutch target transmission torque TTcl2 so as to realize the driver's intention. Set.

  When the range position signal RngPos is in the D range (automatic shift mode), the target gear position is set from the vehicle speed Vsp calculated from the output shaft speed No and the accelerator pedal depression amount Aps, and the range position signal RngPos is M. In the range (manual shift mode), a target shift stage is set according to the driver's upshift operation and downshift operation, and the engine torque command value TTe, target is set to execute the shift operation to the set shift stage. The sleeve 1 position TPslv1, the target sleeve 2 position TPslv2, the target sleeve 3 position TPslv3, the release side clutch target transmission torque TTcl_of, and the engagement side clutch target transmission torque TTcl_on are set, and any of the first clutch 8 and the second clutch 9 is set. Judge whether it is the release side or the engagement side, and release side clutch Target transmission torque TTcl_of, from engagement side clutch target transfer torque TTcl_on, first clutch target transfer torque TTcl1, sets the second clutch target transfer torque TTcl2.

  Further, the transmission control unit 100 realizes the set first clutch target transmission torque TTcl1, second clutch target transmission torque TTcl2, target sleeve 1 position TPslv1, target sleeve 2 position TPslv2, and target sleeve 3 position TPslv3. , Voltages V1_cl1, V2_cl1, V1_cl2, V2_cl2, V1_sft1, V2_sft1, V1_sft2, V2_sft2, applied to the first clutch motor 61b, the second clutch motor 62b, the first shift motor 63b, the second shift motor 64b, and the third shift motor 65b V1_sft3 and V2_sft3 are output.

  The transmission control unit 100 adjusts the voltages V1_cl1 and V2_cl1 applied to the first clutch motor 61b of the first clutch actuator 61 in order to realize a desired first clutch transmission torque, whereby the first clutch motor 61b The current is controlled, and the first clutch 8 is engaged and released.

  Further, the transmission control unit 100 adjusts the voltages V1_cl2 and V2_cl2 applied to the second clutch motor 62b of the second clutch actuator 62 in order to realize a desired second clutch transmission torque, whereby the second clutch motor The current of 62b is controlled, and the second clutch 9 is engaged and released.

  Further, the transmission control unit 100 adjusts the voltages V1_sft1 and V2_sft1 applied to the first shift motor 63b of the shift actuator 63 in order to realize a desired sleeve 1 position, whereby the current of the first shift motor 63b is adjusted. And the first meshing transmission mechanism 21 is engaged and released.

  Further, the transmission control unit 100 adjusts the voltages V1_sft2 and V2_sft2 applied to the second shift motor 64b of the shift actuator 64 in order to realize the desired sleeve 2 position, thereby generating the current of the second shift motor 64b. And the second meshing transmission mechanism 22 is engaged and released.

  Further, the transmission control unit 100 adjusts the voltages V1_sft3 and V2_sft3 applied to the third shift motor 65b of the shift actuator 65 in order to realize the desired sleeve 3 position, thereby generating the current of the third shift motor 65b. And the third meshing transmission mechanism 23 is engaged and released.

  The transmission control unit 100 is provided with a current detection circuit (not shown), and controls the rotational torque of each motor by changing the voltage output so that the current of each motor follows the target current. Yes.

  In this embodiment, as an automatic transmission, a so-called twin-clutch type automatic transmission equipped with two friction transmission mechanisms that transmit or block the power of the driving force source to the output shaft by adjusting the pressing load on the friction surface. Although the transmission is described, it can be applied to various automatic transmissions having a plurality of friction transmission mechanisms that transmit and cut off the power of the driving force source by adjusting the pressing load of the friction surface.

  Next, the specific control contents of the shift control by the automatic transmission control method according to the present embodiment will be described with reference to FIGS.

  FIG. 3 is a flowchart showing an outline of the entire control content of the control method for the automatic transmission according to the embodiment of the present invention.

  The control flow includes step 301 (clutch sharing gain calculation), step 302 (release side clutch torque calculation), and step 303 (engagement side clutch torque calculation).

  The content of FIG. 3 is programmed in the computer 100c of the transmission control unit 100, and is repeatedly executed at a predetermined cycle. In other words, the following steps 301 to 303 are executed by the transmission control unit 100.

  In step 301 (clutch sharing gain calculation), the release side clutch torque sharing gain Gof and the engagement side clutch torque sharing gain Gon are set based on the operating state such as the accelerator opening, the rotation speed, and the shift pattern. Both the release side clutch torque sharing gain Gof and the engagement side clutch torque sharing gain Gon are set in the range of 0 to 1. It is desirable that the release side clutch torque sharing gain Gof and the engagement side clutch torque sharing gain Gon can be set independently.

  Using the sharing gain calculated in step 301 (clutch sharing gain calculation), in step 302 (release side clutch torque calculation) and step 303 (engagement side clutch torque calculation), the release side clutch target torque and the engagement side clutch torque are calculated. The clutch target torque is calculated. Details of step 302 (disengagement side clutch torque calculation) are shown in FIG. 4, and details of step 303 (engagement side clutch torque calculation) are shown in FIG.

  In this embodiment, the torque sharing between the release side clutch and the engagement side clutch in the so-called torque phase is controlled by providing the clutch sharing gain, but instead of step 301, the release side is based on the operating state. A configuration may be adopted in which the torque decrease amount of the clutch and the torque increase amount of the engagement side clutch are set.

  Next, details of step 302 (release side clutch torque calculation) in FIG. 3 will be described with reference to FIG.

  In step 401, it is determined whether or not shifting has started. If the shift is not started, the routine proceeds to step 406, where the release side clutch target torque TTcl_of is terminated as the expected output torque VTe when the torque reduction for the shift or the fuel supply for preventing the overspeed is not shut off. To do. If shifting has started, the process proceeds to step 402.

  In step 402, it is determined whether or not a fuel cut for preventing over-rotation is being executed. When the fuel cut signal Fcut is 1 (execution of fuel cut), the routine proceeds to step 405 where the release side clutch target torque TTcl_of is set to 0 and the process is terminated. When the fuel cut signal Fcut is 0 (no fuel cut is executed), the routine proceeds to step 403.

  In step 403, it is determined whether or not there is a fuel cut experience for preventing over-rotation during the currently executing shift execution period. If the fuel cut signal Fcut has become 1 (fuel cut execution) during the currently executing shift execution period, the routine proceeds to step 405, where the release side clutch target torque TTcl_of is set to 0 and the process ends. When the fuel cut signal Fcut has never been 1 (fuel cut execution), the routine proceeds to step 404 where the release side clutch target torque TTcl_of is calculated by multiplying the engine torque Te by the release side clutch torque sharing gain Gof. finish.

  As described in Steps 402, 403, and 405, it is desirable that the release side clutch target torque TTcl_of is set to 0 after the fuel cut signal Fcut becomes 1 (execution of fuel cut). If it occurs, after the fuel cut signal Fcut becomes 1 (execution of fuel cut), for example, the release side clutch target torque TTcl_of is reduced to 0 with a predetermined slope within a range where no release shock occurs, or to a predetermined value It is good also as a structure which reduces to 0 with a predetermined | prescribed inclination after making it reduce in steps.

  Further, in this embodiment, the release side clutch torque sharing gain Gof is provided to control the release side clutch. However, in the case where the release side clutch torque reduction amount is set in step 301 in FIG. After the fuel cut signal Fcut becomes 1, a more rapid torque decrease amount different from the torque decrease amount set in step 301 is set, and the release side clutch target torque TTcl_of is set to 0 stepwise. You may comprise as follows. Further, when a clutch release shock occurs, the release side clutch target torque TTcl_of may be reduced stepwise to a predetermined value and then gradually reduced to 0 by another torque reduction amount.

  Furthermore, the target engine speed is set, the speed feedback control is executed by the disengagement clutch so that the engine speed matches the target speed, and the feedback correction amount is added to the disengagement clutch target torque TTcl_of. Even in such a configuration, when the fuel cut signal Fcut becomes 1, it is desirable that the release side clutch target torque TTcl_of be quickly set to 0.

  In this embodiment, the predicted output torque VTe is used, but a target engine torque signal based on the accelerator pedal opening, the engine speed, etc. is used, torque reduction for gear shifting, and fuel supply are performed. In the shut-off period, a torque signal that maintains the value of the estimated engine torque Te is used. The torque signal may be used.

  In this way, a shock is prevented from being generated by quickly releasing the release-side clutch when the fuel supply is interrupted to prevent over-rotation.

  Next, details of step 303 (engagement side clutch torque calculation) in FIG. 3 will be described with reference to FIG.

  In step 501, it is determined whether or not shifting has started. When the shift is not started, the process proceeds to Step 506, where the engagement side clutch target torque TTcl_on is set to 0 and the process is ended. If shifting has started, the process proceeds to step 502.

  In step 502, it is determined whether or not a fuel cut for preventing over-rotation is being executed. When the fuel cut signal Fcut is 1 (execution of fuel cut), the routine proceeds to step 505, where the torque output for shifting is reduced or the predicted output torque VTe when the fuel supply for preventing over-rotation is not shut off is used. By multiplying the expected output torque VTe by a shared gain Gon1 that determines the release speed when the fuel cut occurs, the engagement side clutch target torque TTcl_on is calculated and the process ends. It is desirable that the sharing gain Gon1 is set so as to quickly increase to the expected output torque VTe within a range in which the engagement shock does not occur. When the fuel cut signal Fcut is 0 (fuel cut is not executed), the routine proceeds to step 503.

  In step 503, it is determined whether or not there is a fuel cut experience for preventing over-rotation during the currently executing shift execution period. If the fuel cut signal Fcut has become 1 (fuel cut execution) during the currently executing shift execution period, the routine proceeds to step 505, where the engagement side clutch target torque is obtained by multiplying the expected output torque VTe by the sharing gain Gon1. TTcl_on is calculated and the process ends. If the fuel cut signal Fcut has never been 1 (fuel cut execution), the routine proceeds to step 504, where the engagement side clutch target torque TTcl_on is calculated by multiplying the expected output torque VTe by the engagement side clutch torque sharing gain Gon. And exit.

  Thus, by calculating the engagement side clutch target torque TTcl_on using the expected output torque VTe when the fuel is not cut, it is possible to prevent a shock from occurring when the fuel supply is cut off to prevent overspeed, and Prevents engine speed from rising when the fuel supply is shut off.

  Here, instead of step 505, the engine torque Te before the occurrence of fuel cut is stored according to the value of the fuel cut signal Fcut, and the stored engine torque Te is multiplied by the engagement-side clutch torque sharing gain Gon. Thus, the engagement side clutch target torque TTcl_on may be calculated.

  Alternatively, while the fuel supply is shut off (period in which the fuel cut signal Fcut is 1), the value of the engagement-side clutch target torque TTcl_on is maintained until the fuel supply cutoff is canceled (the fuel cut signal Fcut is 0), and the fuel supply cutoff is released. Later, the engagement side clutch target torque TTcl_on may be calculated by multiplying the engine torque Te by the engagement side clutch torque sharing gain Gon again.

  If the clutch is configured to handle the inertia torque for changing the engine speed from the rotation speed before the shift to the rotation speed after the shift, add the inertia torque to the calculation result of Steps 504 and 505. It is desirable that the engagement side clutch target torque TTcl_on be calculated.

  Further, a target engine speed is set, and the rotational speed feedback control is executed by the engagement side clutch so that the engine speed matches the target speed, and the feedback correction amount is added to the engagement side clutch target torque TTcl_on. Even in such a configuration, it is desirable that the feedback control be continued so that the feedback correction amount does not change suddenly or becomes excessively corrected while the fuel supply is cut off (period in which the fuel cut signal Fcut is 1). For example, when the rotational speed feedback control is configured by proportional correction, integral correction, and differential correction, the update of integral correction is stopped and the fuel supply cut-off is canceled (fuel cut-off) while the fuel supply is cut off (period when the fuel cut signal Fcut is 1). Alternatively, the integration correction may be updated again after the signal Fcut becomes 0).

  In this embodiment, the predicted output torque VTe is used, but a target engine torque signal based on the accelerator pedal opening, the engine speed, etc. is used, torque reduction for gear shifting, and fuel supply are performed. In the shut-off period, a torque signal that maintains the value of the estimated engine torque Te is used. The torque signal may be used.

  Next, the first control example of the upshift when configured as shown in FIGS. 3 to 5 will be described with reference to FIG.

  FIG. 6 is a time chart of the upshift when the engine speed at the time of gear shift execution does not reach a high speed and the engine control unit 101 does not shut off the fuel supply for preventing overspeed.

  In FIG. 6, FIG. 6A shows the expected output torque VTe when the solid line indicates the engine torque Te, and the broken line indicates the torque reduction for shifting or the fuel supply for preventing overspeed is not shut off. . FIG. 6B shows the fuel cut signal Fcut. FIG. 6C shows the release side clutch target torque TTcl_of. FIG. 6D shows the engagement side clutch target torque TTcl_on. FIG. 6E shows the engine speed Ne. Ne_p represents the rotational speed corresponding to the gear position before the shift, and Ne_n represents the rotational speed corresponding to the gear position before the gear shift.

  Before the time t1, the vehicle is in a steady running state, and as shown in FIG. 6C, the torque generated by the engine 7 is transmitted by the disengagement side clutch.

  When a shift command is generated at time t1, the engagement side set in step 301 in FIG. 3 is gradually decreased based on the release side clutch torque sharing gain Gof set in step 301 in FIG. 3 while gradually decreasing the release side clutch target torque TTcl_of. Based on the clutch torque sharing gain Gon, the engagement side clutch target torque TTcl_on is gradually increased, and the torque is transferred from the release side clutch to the engagement side clutch. The disengagement side clutch target torque TTcl_of becomes 0, and the torque generated by the engine 7 is transmitted by the engagement side clutch target torque TTcl_on in FIG. finish. From time t1 to time t2 is a so-called torque phase.

  When the switching of the clutch torque is completed at time t2, an operation of shifting the engine speed Ne from the engine speed Ne_p before the shift to the engine speed Ne_n after the shift is started. As shown in FIG. 6D, the engagement-side clutch target torque TTcl_on maintains the expected output torque VTe, and as shown in FIG. 6A, the engine torque gradually decreases and then gradually increases after a predetermined time. Thus, the engine speed Ne converges to the engine speed Ne_n after the shift. The speed change ends at time t3 when the engine speed Ne converges to the engine speed Ne_n after the speed change. Time t2 to time t3 is a so-called inertia phase.

  Next, a second control example of the upshift when configured as shown in FIGS. 3 to 5 will be described with reference to FIG.

  FIG. 7 is a time chart of the upshift when the engine speed at the time of gear change is high and the engine control unit 101 cuts off the fuel supply to prevent overspeed after the start of gear shift. .

  7A, 7B, 7C, 7D and 7E are the same as FIGS. 6A, 6B, 6C, 6D and 6E. .

  Before time t1, the vehicle is in a steady running state, and as shown in FIG. 7C, the torque generated by the engine 7 is transmitted by the disengagement side clutch.

  When a shift command is generated at time t1, the engagement side set in step 301 in FIG. 3 is gradually decreased based on the release side clutch torque sharing gain Gof set in step 301 in FIG. 3 while gradually decreasing the release side clutch target torque TTcl_of. Based on the clutch torque sharing gain Gon, the engagement side clutch target torque TTcl_on is gradually increased, and the torque is transferred from the release side clutch to the engagement side clutch.

  At time t1 ', the engine control unit 101 cuts off the fuel supply to prevent over-rotation, the fuel cut signal Fcut becomes 1, and the engine torque Te decreases rapidly. At this time, the release-side clutch target torque TTcl_of becomes 0 by the processing of steps 401 to 406 shown in FIG. Further, by the processing of steps 501 to 506 in FIG. 5, the engagement side clutch target torque TTcl_on continues to increase to the expected output torque VTe based on the shared gain Gon1 at the time of fuel cut occurrence. The clutch torque at time t2 when the disengagement side clutch target torque TTcl_of becomes 0 and the expected output torque VTe expected to be generated by the engine 7 is transmitted by the engagement side clutch target torque TTcl_on of FIG. The replacement of is completed.

  When the switching of the clutch torque is completed at time t2, an operation of shifting the engine speed Ne from the engine speed Ne_p before the shift to the engine speed Ne_n after the shift is started. As shown in FIG. 6D, the engagement-side clutch target torque TTcl_on maintains the expected output torque VTe, and the engine speed Ne converges to the engine speed Ne_n after the shift.

  At time t2 ′, the engine control unit 101 returns from the fuel supply cutoff to prevent overspeed, the fuel cut signal Fcut becomes 0, and the engine torque Te increases rapidly. The engagement side clutch target torque TTcl_on maintains the expected output torque VTe as shown in FIG. The speed change ends at time t3 when the engine speed Ne converges to the engine speed Ne_n after the speed change.

  As shown in FIGS. 3 to 5, when the engine fuel injection is shut off, the release side clutch is quickly released, and the engagement side clutch is configured to continue the engagement control, thereby preventing engine overspeed. For this reason, it is possible to prevent the occurrence of shift shocks when the engine fuel supply is shut off and when the engine is shut off, and to prevent the engine speed from rising when the engine fuel supply is shut off. The feeling can be prevented from being lowered.

  Next, a third control example of upshift when configured as shown in FIGS. 3 to 5 will be described with reference to FIG.

  FIG. 8 is a time chart of the upshift when the engine speed at the time of executing the shift is high and the engine control unit 101 cuts off the fuel supply for preventing the overspeed before starting the shift. is there.

  8 (A), (B), (C), (D), and (E) are the same as FIGS. 6 and 7 (A), (B), (C), (D), and (E). It is the same.

  Before the time t1 ′, the vehicle is in a steady running state, and as shown in FIG. 8C, the torque generated by the engine 7 is transmitted by the disengagement side clutch.

  At time t1 ', the engine control unit 101 cuts off the fuel supply to prevent over-rotation, the fuel cut signal Fcut becomes 1, and the engine torque Te decreases rapidly. At this time, the release side clutch target torque TTcl_of maintains the expected output torque VTe by the processing of steps 401 to 406 shown in FIG. Further, the engagement-side clutch target torque TTcl_on is kept at 0 by the processing of Steps 501 to 506 in FIG.

  When a shift command is generated at time t1, the release side clutch target torque TTcl_of becomes 0 by the processing of steps 401 to 406 shown in FIG. 4, and the engagement side clutch target torque TTcl_on becomes 0 by the processing of steps 501 to 506 of FIG. The expected output torque increases to VTe. The clutch torque at time t2 when the disengagement side clutch target torque TTcl_of becomes 0 and the expected output torque VTe expected to be generated by the engine 7 is transmitted by the engagement side clutch target torque TTcl_on of FIG. The replacement of is completed.

  When the switching of the clutch torque is completed at time t2, an operation of shifting the engine speed Ne from the engine speed Ne_p before the shift to the engine speed Ne_n after the shift is started. As shown in FIG. 8D, the engagement-side clutch target torque TTcl_on maintains the expected output torque VTe, and the engine speed Ne converges to the engine speed Ne_n after the shift.

  At time t2 ′, the engine control unit 101 returns from the fuel supply cutoff to prevent overspeed, the fuel cut signal Fcut becomes 0, and the engine torque Te increases rapidly. The engagement side clutch target torque TTcl_on maintains the expected output torque VTe as shown in FIG. The speed change ends at time t3 when the engine speed Ne converges to the engine speed Ne_n after the speed change.

  With this configuration, even if the engine fuel supply is shut off to prevent engine over-rotation before the start of shifting, and is restored from the shut-off after starting the shifting, the engine fuel injection is performed before starting the shifting. When shut off, the disengagement clutch maintains the engaged state and is released immediately after the start of shifting, and the engagement clutch immediately executes the engagement control, thus shutting off the engine fuel supply to prevent engine overspeed. , It is possible to prevent the occurrence of a shift shock when the shut-off is restored, and to prevent the engine speed from rising when the engine fuel supply is shut off, thereby preventing the shift feeling from being lowered.

  When a predetermined inclination is provided to the release side clutch in the section from time t1 to time t2 in FIG. 8, the release curve of the release side clutch target torque TTcl_of in the section from time t1 to time t2 in FIG. It is desirable that the engagement curve of the engagement-side clutch target torque TTcl_on or both the release curve of the release-side clutch target torque TTcl_of and the engagement curve of the engagement-side clutch target torque TTcl_on be convex downward.

  In each embodiment, the first clutch 8 and the second clutch 9 are described as dry clutches, but may be configured as wet multi-plate clutches. When a wet multi-plate clutch is used, for example, before changing the clutch torque executed from time t1 to time t2 in FIG. 6, hydraulic oil is supplied to the hydraulic chamber of the engagement side clutch and engagement of the engagement side clutch is started. So-called precharge control is required to make the state immediately before. Therefore, when the wet multi-plate clutch is used, it is desirable to configure the determination in step 401 in FIG. 4 and step 501 in FIG. 5 not as a shift start determination but as a completion determination of precharge control.

1 is a system configuration diagram showing an embodiment of an automatic transmission control method according to the present invention. FIG. 1 is a block diagram showing an input / output signal relationship between a transmission control unit 100 and an engine control unit 101 used in a system configuration showing an embodiment of an automatic transmission control method according to an embodiment of the present invention. It is a flowchart which shows the outline of the control content of the control method of the automatic transmission by one Embodiment of this invention. It is a flowchart which shows the processing content of the releasing side clutch torque calculation shown in FIG. It is a flowchart which shows the processing content of the engagement side clutch torque calculation shown in FIG. It is a time chart which shows the 1st shift control example of the control method of the automatic transmission by one embodiment of this invention. It is a time chart which shows the 2nd example of shift control of the control method of the automatic transmission by one embodiment of this invention. It is a time chart which shows the 3rd shift control example of the control method of the automatic transmission by one embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st drive gear 2 2nd drive gear 3 3rd drive gear 4 4th drive gear 5 5th drive gear 7 Engine 8 1st clutch 9 2nd clutch 11 1st driven gear 12 2nd driven gear 13 3rd driven gear 14 4th driven gear 15 5th driven gear 21 1st synchronous meshing mechanism 22 2nd synchronous meshing mechanism 23 3rd synchronous meshing mechanism 31 1st input shaft rotation sensor 32 2nd input shaft rotation sensor 33 Output shaft rotation sensor 41 Transmission first input shaft 42 Transmission second input shaft 43 Output shaft 50 Automatic transmission 61 First clutch actuator 62 Second clutch actuator 63 First shift actuator 64 Second shift actuator 65 Third shift actuator 100 Transmission control Unit 101 Engine control unit 103 Communication means 106 Lever 201 accelerator opening degree sensor 202 brake switch

Claims (6)

A control method for an automatic transmission including a first friction transmission mechanism and a second friction transmission mechanism that perform transmission and interruption of torque generated by an engine to an output shaft by adjusting a pressing load on a friction surface. Then, after the upshift is started, a torque phase for releasing the first friction transmission mechanism at a predetermined release speed and engaging the second friction transmission mechanism at a predetermined engagement speed is executed, and the generated torque of the engine and the second A control method for an automatic transmission that executes an inertia phase for shifting the rotational speed of the engine from the rotational speed before the shift to the rotational speed after the shift in a predetermined shift time by controlling the transmission torque of the friction transmission mechanism of
After the start of upshifting, when the engine fuel injection is cut off in the torque phase to prevent over-rotation of the engine, the first friction transmission mechanism is separated from the predetermined release speed. A method for controlling an automatic transmission, which is released according to a rapid release speed, and wherein the second friction transmission mechanism continues the engagement control in the torque phase and the inertia phase.   The method for controlling an automatic transmission according to claim 1, wherein an estimated output torque when the fuel injection of the engine is not cut off is estimated, and the fuel injection of the engine is cut off during the torque phase or the inertia phase. A control method for an automatic transmission that continues the engagement control by controlling the transmission torque of the second friction transmission mechanism using the predicted output torque.   2. The method for controlling an automatic transmission according to claim 1, wherein an estimated output torque when the fuel injection of the engine is not cut off is estimated, and the fuel of the engine is prevented before the upshift starts to prevent over-rotation of the engine. When injection is interrupted, the first friction transmission mechanism is maintained in the engaged state using the predicted output torque, and after the upshift starts, the first friction transmission mechanism is separated from the predetermined release speed. A control method for an automatic transmission that releases at a faster release speed and increases the transmission torque of the second friction transmission mechanism using the predicted output torque. A control device for an automatic transmission having a first friction transmission mechanism and a second friction transmission mechanism that perform transmission and interruption of torque generated by an engine to an output shaft by adjusting a pressing load on a friction surface. Then, after the upshift is started, a torque phase for releasing the first friction transmission mechanism at a predetermined release speed and engaging the second friction transmission mechanism at a predetermined engagement speed is executed, and the generated torque of the engine and the second A control device for an automatic transmission that executes an inertia phase for shifting the rotational speed of an engine from a rotational speed before a shift to a rotational speed after a shift in a predetermined shift time by controlling a transmission torque of the friction transmission mechanism of
After the start of upshifting, when the engine fuel injection is interrupted in the torque phase to prevent engine overspeed, the first friction transmission mechanism is released more rapidly than the predetermined release speed. The automatic transmission control device according to claim 1, wherein the second friction transmission mechanism is controlled so as to continue the engagement control in the torque phase and the inertia phase.   5. The control apparatus for an automatic transmission according to claim 4, wherein when the engine fuel injection is not cut off, an estimated output torque is estimated, and the engine fuel injection is cut off in the torque phase or the inertia phase. A control apparatus for an automatic transmission, wherein the control is performed so as to continue the engagement control by controlling the transmission torque of the second friction transmission mechanism using the predicted output torque.   5. The control apparatus for an automatic transmission according to claim 4, wherein an estimated output torque when the fuel injection of the engine is not shut off is estimated, and the engine fuel injection is performed to prevent over-rotation of the engine before the start of the upshift. Is interrupted, the first friction transmission mechanism is maintained in the engaged state using the predicted output torque, and after the upshift starts, the first friction transmission mechanism is separated from the predetermined release speed. A control device for an automatic transmission, which is controlled to release at a rapid release speed and to increase the transmission torque of the second friction transmission mechanism using the predicted output torque.

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