JP5192265B2 - Control device for continuously variable transmission - Google Patents

Description

  The present invention relates to a control device for a continuously variable transmission.

  Conventionally, in a continuously variable transmission, when the driver switches the shift lever from the N range to the D range (or R range) at the start, the movement is transmitted to the manual valve by a physical interlocking mechanism, and this manual valve is transmitted to the clutch base. The forward clutch (or reverse clutch) is fastened by displacing the pressure and the piston oil chamber of the forward clutch (or the position where the clutch original pressure and the piston oil chamber of the reverse clutch (brake) are in communication). The engine torque is transmitted to the transmission without permission.

  When the shift lever is switched from the N range to the D range (or R range), the inhibitor switch signal indicates that it is in the D range (or R range), and the movement of the select lever is physically transmitted to the spool of the manual valve. Then, connect the clutch and manual valve. At this time, forward clutch (or reverse clutch) engagement is completed through roughly three phases. The three phases are a precharge phase, a fastening progress phase, and a final fastening phase. In the precharge phase, the hydraulic circuit is filled and the invalid stroke portion of the clutch is eliminated by a high hydraulic pressure command value. In the fastening progress phase, the hydraulic pressure command value is once lowered to a predetermined value after the precharge phase, and then the hydraulic pressure command value is increased at a predetermined increase rate. In the final engagement phase, the hydraulic pressure command value is increased to the maximum value at the time of clutch engagement in a short time after the engagement progress phase.

  For these phases, when the clutch hydraulic pressure is set to open control by the hydraulic pressure command value, the hydraulic pressure command value that is stored as standard in the ATCU ROM at the time of shipment due to changes over time in the clutch, product variations, hydraulic oil temperature, etc. If the reference value (nominal value) is left as it is, problems such as a delay in fastening or a fastening shock due to fastening too early will occur.

  Further, when the driver depresses the accelerator when the clutch is not engaged, the engine rotation speed rapidly increases. In addition, when the manual valve is in communication and the clutch is engaged after the engine speed has suddenly increased, an engagement shock occurs, or momentary large torque is input to the V-belt of the continuously variable transmission, causing belt slippage. It may occur.

Therefore, after switching from the N range to the D range (or R range), the throttle opening is kept idle until the clutch input side rotational speed (turbine rotational speed) reaches a predetermined rotational speed (0 km / h when the vehicle is stopped). There is one that closes to the time and suppresses a rapid increase in engine rotation speed (for example, Patent Document 1).
Japanese Patent Laid-Open No. 2004-267341

  However, the above-described invention requires a sensor for detecting the input rotational speed (turbine rotational speed) of the clutch, and a continuously variable transmission that does not include such a sensor can suppress a rapid increase in engine rotational speed. However, there are problems such as engine blow-off, clutch engagement shock, and belt slippage cannot be suppressed.

  The present invention was devised to solve such problems, and without using a sensor for detecting the input rotational speed of the clutch, the communication state between the manual valve and the clutch is determined, and the engine output regulation is accurately controlled. The purpose is to suppress engine blow, clutch engagement shock, and belt slip.

The present invention relates to a control device for a continuously variable transmission that controls a continuously variable transmission that includes a belt that is wound around a primary pulley and a secondary pulley and whose contact radius changes with the width of the groove. Inhibitor switch that outputs a signal corresponding to the operation position, and a manual that is displaced according to the select lever operation position and supplies hydraulic pressure to one of the forward clutch and the reverse clutch interposed between the primary pulley and the engine. A hydraulic control means for controlling the hydraulic pressure supplied to the forward clutch or the reverse clutch, a primary pulley rotational speed detecting means for detecting the rotational speed of the primary pulley, based on the valve, the output signal of the inhibitor switch and the driving state of the vehicle; Based on the output signal of the inhibitor switch, the select lever operating position is in the non-traveling position. If it is determined that it has been switched to the al travel position, the engine output restricting means for restricting the engine output, after regulating the engine output, when the pulse signal is output from the primary pulley rotation speed detecting means, engine output Engine output restriction release means for releasing the restriction.

  According to the present invention, when the select lever is changed from the non-traveling position to the traveling position and the regulation of the engine output is started, the regulation of the engine output is released when the pulse signal is output by the primary pulley rotation speed detecting means. Thus, it is possible to accurately regulate the engine output and suppress engine blown-off, clutch engagement shock, and belt slip.

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

  FIG. 1 is a diagram illustrating an embodiment of a clutch engagement control device for an automatic transmission according to the present invention.

  The automatic transmission includes a hydraulic pump 10, a torque converter 20, a forward / reverse switching clutch 30, and a CVT transmission unit 40, and is controlled by a control unit 60. The automatic transmission receives a driving force from the engine 70, shifts the driving force, and outputs it to the driving wheels 80.

  The hydraulic pump 10 is driven by the engine 70 to pump oil. The pressure-fed oil is adjusted by the line pressure adjusting device 11. The adjusted hydraulic pressure is further adjusted by the primary pressure adjusting device 12 and the secondary pressure adjusting device 13 and supplied to the primary pulley 41 and the secondary pulley 42, and the primary pulley 41 and the secondary pulley 42 are operated to change speed. . The hydraulic pressure branched by the line pressure adjusting device 11 is sent to the forward clutch piston chamber 32a and the reverse brake piston chamber 33a via the clutch pressure adjusting device (hydraulic control means) 14 and the manual valve 57 to control the clutch engagement. .

  The torque converter 20 is provided between the engine 70 and the forward / reverse switching clutch 30 and transmits the driving force of the engine 70 by the internal oil flow. The torque converter 20 has a lockup mechanism for eliminating a rotational difference between the pump impeller and the turbine runner.

  The forward / reverse switching clutch 30 includes a planetary gear 31 that switches a power transmission path between the engine side and the CVT transmission unit side, a forward clutch 32, and a reverse brake 33. The forward clutch 32 is connected to the forward clutch piston, and is fastened to the planetary gear 31 by the hydraulic pressure (forward clutch pressure) supplied to the forward clutch piston chamber 32a when the vehicle moves forward. The reverse brake 33 is connected to the reverse brake piston and is fastened to the planetary gear 31 by the force of hydraulic pressure (reverse brake pressure) supplied to the reverse brake piston chamber 33a when the vehicle reverses. Further, no hydraulic pressure is supplied at the neutral position (neutral or parking), and both the forward clutch 32 and the reverse brake 33 are released. When the forward clutch 32 is engaged with the planetary gear 31, forward rotation is output, and when the reverse brake 33 is engaged with the planetary gear 31, reverse rotation is output.

  The forward clutch 32 and the reverse brake 33 are exclusively engaged, and at the time of forward movement, the forward clutch pressure is supplied to fasten the forward clutch 32, and the reverse brake pressure is connected to the drain to release the reverse brake 33. . On the other hand, during reverse travel, the forward clutch pressure is connected to the drain to release the forward clutch 32, and the reverse brake pressure is supplied to engage the reverse brake 33. In the neutral position, the forward clutch pressure and the reverse brake pressure are connected to the drain, and both the forward clutch 32 and the reverse brake 33 are released.

  The CVT transmission unit 40 includes a primary pulley 41, a secondary pulley 42, and a V belt 43.

  The primary pulley 41 is an input shaft side pulley that inputs the driving force of the engine 70. The primary pulley 41 has a fixed conical plate 41a that rotates integrally with the input shaft 41c, a V-shaped pulley groove that is disposed opposite to the fixed conical plate 41a, and a hydraulic pressure that acts on the primary pulley (hereinafter referred to as the primary pulley). And a movable conical plate 41b that can be displaced in the axial direction by "primary pressure". The rotation speed (input rotation) of the primary pulley 41 is detected by a primary pulley rotation speed sensor (primary pulley rotation speed detecting means) 41d.

  The secondary pulley 42 transmits the driving force transmitted by the V belt 43 to the driving wheel 80 via an idler gear or a differential gear. The secondary pulley 42 has a fixed conical plate 42a that rotates integrally with the output shaft 42c, a V-shaped pulley groove disposed opposite to the fixed conical plate 42a, and a hydraulic pressure (hereinafter referred to as hydraulic pressure) that acts on the secondary pulley. And a movable conical plate 42b that can be displaced in the axial direction according to "secondary pressure"). In addition, the pressure receiving area of the secondary pulley and the pressure receiving area of the primary pulley are the same or almost the same. The speed of rotation (output rotation) of the secondary pulley 42 is detected by a secondary pulley rotation speed sensor 42d. Note that the vehicle speed is calculated from the rotational speed of the secondary pulley 42.

  The V belt 43 is wound around the primary pulley 41 and the secondary pulley 42, and transmits the driving force input to the primary pulley 41 to the secondary pulley 42.

  The primary pulley rotation speed sensor 41d faces an output gear (not shown) attached to the primary pulley 41. Teeth are formed at equal intervals on the outer periphery of the output gear. For this reason, the output waveform detected by the primary pulley rotation speed sensor 41d is a pulse having an equal pitch at a constant vehicle speed. That is, the primary pulley rotation speed sensor 41 d is configured by a pulse sensor that outputs a pulse signal synchronized with the rotation of the primary pulley 41.

  When the position of the select lever 51 is in the N range (non-traveling position) and the vehicle is stopped, rotation from the engine 70 is not transmitted to the primary pulley 41, so the primary pulley 41 rotates. Not. Therefore, the primary pulley rotation speed sensor 41d does not output a pulse signal. However, when the position of the select lever 51 is changed from the N range to, for example, the D range (traveling position), forward clutch pressure is supplied to fasten the forward clutch 32, and the engine 70 is connected to the output side of the forward clutch 32. Torque is transmitted gradually from. Then, torque is transmitted to the primary pulley 41, and the primary pulley 41 rotates. As a result, the primary pulley rotation speed sensor 41 d outputs a pulse signal to the control unit 60.

  The control unit 60 inputs the signals of the primary rotational speed sensor 41d and the secondary rotational speed sensor 42d, calculates the current gear ratio from these signals, and controls the primary pressure and the secondary pressure so that the desired gear ratio is obtained. . Further, a clutch pressure command signal is output to the clutch pressure adjusting device 14 by a signal from the inhibitor switch 56 to control the forward / reverse switching clutch 30.

  FIG. 2 is a diagram showing the structure of the transmission.

  The select lever 51 is rotatable around a fulcrum 51a. The select lever 51 is connected to a wire 52. The other end of the wire 52 is connected to the link 53. The link 53 performs a rotational motion around the fulcrum 53a. The other end of the link 53 is connected to the slider 54. The slider 54 connects the switch 56a of the inhibitor switch 56 via a connecting rod 55a. The switch 56a enables conduction between the power supply terminal 56b and any one of the D range terminal 56c, the N range terminal 56d, and the R range terminal 56e. The slider 54 connects the manual valve 57 via a connecting rod 55b.

  When the driver operates the select lever 51 as indicated by the arrow, the link 53 rotates as indicated by the arrow via the wire 52. Then, the slider 54 moves as indicated by an arrow. Then, the switch 56a is moved in accordance with the movement of the slider 54, and the power supply terminal 56b is electrically connected to any one of the D range terminal 56c, the N range terminal 56d, and the R range terminal 56e. At the same time, the manual valve 57 moves in accordance with the movement of the slider 54 to control the hydraulic pressure supplied to the forward / reverse switching clutch 30.

  At this time, for example, although the power supply terminal 56b and the D range terminal 56c are electrically connected by the operation of the select lever 51, the manual valve 57 and the forward clutch are not in communication with each other, but the forward clutch 32 is not connected. May not be able to supply hydraulic pressure.

  At this time, although the clutch is not engaged, the driver has selected the D range, so the accelerator pedal may be subsequently depressed. Then, since the clutch is in a non-coupled state, the driving force of the engine is not transmitted to the driving wheels, and the engine is blown away.

  In this state, the driver may push the select lever 51 further in the D direction, or the select lever 51 may be further moved in the D direction by the engine roll when the engine is idling, and the manual valve 57 may be in the D range.

  In such a case, since the INH signal of the D range is sent from the inhibitor switch 56 at the time of the first operation of the select lever, the INH signal does not change even if it is pushed further in the D direction after the air blows. Therefore, normal select control cannot be performed. However, the actual clutch pressure is supplied by moving the manual valve 57, and the clutch is engaged. However, since the engine is in a state where the engine is increased to a high rotational speed by air blowing, a large engagement shock may occur when the clutch is engaged, and slipping may occur in the V-belt 43.

  In order to suppress such a phenomenon, there is a control method for restricting the engine output when the select lever 51 is changed from the N range to the D range. In the present invention, the engine output is accurately regulated.

  Next, clutch hydraulic pressure control performed by the clutch pressure adjusting device 14 will be described with reference to the flowchart of FIG.

  In step S1, the inhibitor switch 56 reads the current INH signal.

  In step S2, it is determined whether a flag (hereinafter referred to as an ND switching flag) F_nd indicating whether or not the select lever 51 has been switched from the N range to the D range is off. If the ND switching flag F_nd is off, the process proceeds to step S3. If the ND switching flag F_nd is on, the process proceeds to step S7. In the first determination of this control, the ND switching flag F_nd is off, and the process proceeds to step S3.

  In step S3, the previous control INH signal is read and compared with the current INH signal read in step S1. Then, it is determined whether or not the select lever 51 has been switched from the N range to the D range. If the select lever 51 is switched from the N range to the D range, the process proceeds to step S4. If the select lever 51 is not switched from the N range to the D range, the process proceeds to step S29.

  In step S4, the ND switching flag F_nd is turned on. Also, the phase flag F_phase is set to zero indicating the initialization phase.

  In step S5, the precharge pressure P_pc, precharge time T_pc, engagement initial pressure P_start, first ramp increase rate ΔP_r1, first ramp time T_r1, second ramp increase rate ΔP_r2, and second ramp time T_r2 are read from the ROM of the control unit 60. Read the nominal value of.

  In step S6, the learning correction amount P_offset is read from the control unit 60. The learning correction amount P_offset is stored in a storage area of a non-volatile rewritable memory such as an EEPROM. When the correction amount is not learned, the learning correction amount P_offset is zero.

  In step S2, if the ND switching flag F_nd is on, it is determined in step S7 whether the current phase is an initialization phase. Here, it is determined whether or not the phase flag F_phase is zero indicating the initialization phase. When the phase flag F_phase is zero, the process proceeds to step S8, and when the phase flag F_phase is not zero, the process proceeds to step S10.

  In step S8, since the ND switching flag F_nd is on and the nominal value is read, the phase flag F_phase is set to 1 to indicate the transition to the precharge phase.

  In step S9, a first timer tm_1 for determining the elapsed time of the precharge phase is initialized to zero.

  In step S10, it is determined whether the current phase is a precharge phase. Here, it is determined whether or not the phase flag F_phase is 1 indicating the precharge phase. If the phase flag F_phase is 1, the process proceeds to step S11. If the phase flag F_phase is not 1, the process proceeds to step S17.

  In step S11, it is determined whether or not the first timer tm_1 has reached the precharge time T_pc read in step S5. If the first timer tm_1 has not reached the precharge time T_pc, the process proceeds to step S12. If the first timer tm_1 has reached the precharge time T_pc, the process proceeds to step S14.

  In step S12, the precharge pressure P_pc read in step S5 is set as the clutch hydraulic pressure command value P_target. The precharge pressure P_pc is the maximum pressure of the clutch hydraulic pressure command value, and thereby the invalid stroke of the forward clutch 32 can be quickly reduced.

  In step S13, the first timer tm_1 is incremented.

  In step S11, when the first timer tm_1 has reached the precharge time T_pc, the precharge phase has ended. Therefore, in step S14, the phase flag F_phase is set to 2 indicating the fastening progress phase.

  In step S15, the second timer tm_2 for determining the elapsed time of the fastening progress phase is initialized to zero.

  In step S16, the clutch hydraulic pressure command value P_target is set to the total value of the engagement initial value P_start read in step S5 and the learning correction amount P_offset read in step S6.

  When the sign of the learning correction amount P_offset read out in step S6 is negative, the clutch hydraulic pressure command value P_target is set to a value smaller than the engagement initial value P_start.

  By adding (subtracting) the learning correction amount P_offset to the engagement initial value P_start, it is possible to suppress clutch engagement delay, engagement shock, and the like caused by clutch deterioration over time, variation among products, hydraulic oil temperature, and the like. .

  If it is determined in step S10 that the phase flag F_phase is not 1, it is determined in step S17 whether or not the current phase is a fastening progress phase. Here, it is determined whether or not the phase flag F_phase is 2 indicating the fastening progress phase. If the phase flag F_phase is 2, the process proceeds to step S18. If the phase flag F_phase is not 2, the process proceeds to step S24.

  In step S18, it is determined whether or not the second timer tm_2 has reached the first ramp time T_r1 read in step S5. If the second timer tm_2 has not reached the first ramp time T_r1, the process proceeds to step S19. If the second timer tm_2 has reached the first ramp time Tr_1, the process proceeds to step S21.

  In step S19, the clutch hydraulic pressure command value P_target is calculated by adding the first ramp increase rate ΔP_r1 read in step S5 to the clutch hydraulic pressure command value P_target 'in the previous control.

  Here, when it is determined that the current phase is the fastening progress phase, one time is determined from either the fastening initial value P_start or the value obtained by adding (subtracting) the learning correction value P_offset to the fastening initial value P_start. The clutch hydraulic pressure command value P_target increases at the rate of the first ramp increase rate ΔP_r1 for each control cycle.

  In step S20, the second timer tm_2 is incremented.

  If the second timer tm_2 has reached the first ramp time Tr_1 in step S18, the fastening progress phase has ended. Therefore, in step S21, the phase flag F_phase is set to 3 indicating the final engagement phase.

  In step S22, a third timer tm_3 for determining the elapsed time of the final engagement phase is initialized to zero.

  In step S23, the clutch hydraulic pressure command value P_target is calculated by adding the second ramp increase rate ΔP_r2 to the clutch hydraulic pressure command value P_target 'in the previous control.

  At this time, since the forward clutch 32 has already started torque transmission, in order to quickly complete the engagement of the forward clutch 32, the second ramp increase rate ΔP_r2 larger than the first ramp increase rate ΔP_r1 Increase the clutch command oil pressure P_target.

  If it is determined in step S17 that the phase flag F_phase is not 2, it is determined in step S24 whether the third timer tm_3 has reached the second ramp time T_r2 read out in step S5. If the third timer tm_3 has not reached the second ramp time T_r2, the process proceeds to step S25. If the third timer tm_3 has reached the second ramp time T_r2, the process proceeds to step S27.

  In step S25, the clutch hydraulic pressure command value P_target is calculated by adding the second ramp increase rate ΔP_r2 to the clutch hydraulic pressure command value P_target 'in the previous control.

  In step S26, the third timer tm_3 is incremented.

  If it is determined in step S24 that the third timer tm_3 has reached the second ramp time T_r2, it is determined in step S27 that the forward clutch 32 has been engaged, and the ND switching flag F_nd is turned off.

  In step S28, the clutch hydraulic pressure command value P_target is set to the normal clutch engagement pressure.

  If it is determined in step S3 that the select lever 51 has not been switched from the N range to the D range, it is determined in step S29 whether or not the select lever 51 is in the D range. The process proceeds to S30, and if the select lever 51 is in the N range, the process proceeds to Step S31.

  In step S30, the clutch hydraulic pressure command value P_target is set to the normal clutch engagement pressure.

  In step S31, the clutch hydraulic pressure command value P_target is set to the minimum pressure. The minimum pressure is, for example, 0 MPa. As a result, the forward clutch 32 is maintained in the released state.

  In step S32, the forward clutch pressure is controlled by the clutch pressure adjusting device 14 so that the clutch hydraulic pressure command value P_target set by the above control is obtained.

  By the above control, when the select lever 51 is changed from the N range to the D range, the forward clutch pressure is supplied and the forward clutch 32 is engaged according to the clutch hydraulic pressure command value P_target.

  Next, engine output restriction control will be described with reference to the flowchart of FIG.

  In step S101, it is determined whether the engine output restriction flag F_eng_lim is on. When the engine output restriction flag F_eng_lim is off, the process proceeds to step 102, and when the engine output restriction flag F_eng_lim is on, the process proceeds to step S110. At the time of the first determination after starting this control, since the engine output restriction flag F_eng_lim is off, the process proceeds to step S102.

  In step S102, it is determined whether the ND switching flag F_nd has been changed from off to on. This determination is made based on whether or not the select lever 51 has been switched from the N range to the D range in step S3 of the flowchart shown in FIG. 3, and whether or not the ND switching flag F_nd is turned on in step S4. . If the ND switching flag F_nd is changed from off to on, the process proceeds to step S103. If the ND switching flag F_nd is maintained in the off or on state, the current determination control is terminated. .

  In step S103, the engine output restriction flag F_eng_lim is turned on, and the pulse detection flag F_pulse is turned off. Note that the initial value after activation of the control unit 60 is both off.

  In step S104, the reference output restriction value Rev_lim and the restriction release change rate ΔRev_lim are read from the control unit 60. The reference output restriction value Rev_lim is a restriction value for setting the engine output to an output equivalent to an idle. In this embodiment, the reference output restriction value Rev_lim is a restriction value for setting the engine rotation speed to an engine rotation speed equivalent to an idle. Further, the regulation release change rate ΔRev_lim is a preset value, and when the select lever 51 is changed from the N range to the D range, when the forward clutch 32 is engaged, a rapid increase in the engine speed is prevented, This is a change amount that increases the command engine output restriction value Rev_lim_target so that the driver does not feel uncomfortable.

  In this embodiment, the engine speed is regulated as a method for regulating the engine output, but the engine torque may be regulated instead.

  In step S105, the reference output restriction value Rev_lim is set as the initial value of the command engine output restriction value Rev_lim_target. As a result, when the select lever 51 is changed from the N range to the D range, an output equivalent to the idle is instructed as the command engine output restriction value Rev_lim_target. Therefore, it is possible to suppress idling of the engine 70 (step S105 constitutes engine output restriction means).

  In step S106, a signal is read from the primary pulley rotation speed sensor 41d.

  In step S107, it is determined whether or not a pulse signal is output from the primary pulley rotation speed sensor 41d. If a pulse signal is output from the primary pulley rotation speed sensor 41d, the process proceeds to step S108. If no pulse signal is output from the primary pulley rotation speed sensor 41d, the current determination control is terminated.

  When the manual valve 57 and the forward clutch 32 communicate with each other and the forward clutch 32 starts to be engaged, torque is transmitted to the primary pulley 41 and the primary pulley 41 rotates. Therefore, the communication state between the manual valve 57 and the forward clutch 32 can be determined by determining whether or not a pulse signal is output from the primary pulley rotation speed sensor 41d.

  In step S108, when a pulse signal is output from the primary pulley rotation speed sensor 41d, the pulse detection flag F_pulse is turned on.

  In step S109, the restriction release change rate ΔRev_lim is added to the command engine output restriction value Rev_lim_target ′ at the time of the previous determination control. As a result, the command engine output restriction value Rev_lim_target is increased. That is, the regulation of engine output is gradually relaxed, and the upper limit value of the engine speed increases. Further, the current command engine output restriction value Rev_lim_target is stored in the control unit 60 (step S109 constitutes an engine output restriction release means).

  If it is determined in step S101 that the engine output restriction flag F_eng_lim is on, in step S110, it is determined whether or not the ND switching flag F_nd is changed from on to off. If the ND switching flag F_nd is changed from on to off, the process proceeds to step S112. If the ND switching flag F_nd is not changed from on to off, the process proceeds to step S111.

  The ND switching flag F_nd is turned off when the switching from the N range to the D range is normally completed, or when the select lever 51 is further changed from the D range to the N range during the switching control.

  In step S111, it is determined whether the pulse detection flag F_pulse is on. If the pulse detection flag F_pulse is on, the process proceeds to step S109, and the restriction release change rate ΔRev_lim is added to the previously determined command engine output restriction value Rev_limi_target 'to gradually release the restriction. On the other hand, if the pulse detection flag F_pulse is off, the process proceeds to step S106 and the above control is repeated.

  In step S112, since the ND switching flag F_nd has been changed from on to off, the engine output restriction flag F_eng_lim is set to off.

  In step S113, the pulse detection flag F_pulse is turned off.

  In step S114, the command engine output restriction value Rev_lim_target is set to the maximum value of the engine speed. Thereby, it is possible to prevent the actual engine rotation speed from becoming higher than the engine rotation speed regulated by this control. The engine rotation speed may not be restricted.

  With the above control, the communication state between the manual valve 57 and the forward clutch 32 can be accurately determined based on the pulse signal output from the primary pulley rotational speed sensor 41d, and the select lever 51 is moved from the N range to the D range. It is possible to accurately regulate the engine output when the range is changed.

  Next, changes in the engine speed and the like will be described with reference to the time charts of FIGS. FIG. 5 is a time chart showing changes in engine speed and the like when the present invention is not used. FIG. 6 is a time chart showing changes in engine rotational speed and the like when the present invention is used.

  When the present invention is not used, that is, when the sensor for detecting the input side rotational speed of the clutch is not used, the select lever is changed from the N range to the D range at time t1, and from the N range by the INH signal from the inhibitor switch. When the change to the D range is detected, the engine output restriction is started, and the engine rotation speed becomes a rotation speed equivalent to an idle.

  Then, at time t2 when the fixed time has elapsed from time t1, the engine output restriction is gradually relaxed, and the engine speed gradually increases. However, when the clutch actual pressure is deviated to a lower side with respect to the clutch hydraulic pressure command value, that is, when the communication timing of the manual valve and the forward clutch is later than the preset communication timing (broken line in FIG. 5). ) Is insufficient in clutch transmission torque capacity. In such a state, if the engine output restriction is gradually released, the engine rotation speed increases and the engine may be blown even though the forward clutch engaging force is small. Further, when the forward clutch is subsequently engaged, a clutch engagement shock may occur, and the V belt may slip.

  When the present invention is used, if it is determined at time t1 that the ND switching flag F_nd is changed from off to on by the INH signal from the inhibitor switch 56, the command engine output restriction value Rev_lim_target is set as the reference output restriction value Rev_lim. The engine rotation speed is set to a rotation speed equivalent to idle.

  When a pulse signal is output from the primary pulley rotational speed sensor 41d at time t2, it is determined that the manual valve 57 and the forward clutch 32 are in communication and the forward clutch pressure is supplied, and the command engine output restriction is determined. The value Rev_lim_target is increased from the reference output restriction value Rev_lim at a ratio of the reference cancellation change rate ΔRev_lim.

  As described above, even when the sensor for detecting the input side rotational speed of the clutch is not provided, the communication state between the manual valve 57 and the forward clutch 32 can be established by using the pulse signal output from the primary pulley rotational speed sensor 41d. It can be determined accurately.

  Further, even when the actual clutch pressure is shifted to a lower side with respect to the clutch hydraulic pressure command value P_target (broken line in FIG. 6), the command is output after the pulse signal is output from the primary pulley rotation speed sensor 41d at time t3. The engine output restriction value Rev_lim_target is increased from the reference output restriction value Rev_lim at a ratio of the reference cancellation change rate ΔRev_lim.

  Thus, even when the clutch actual pressure is deviated to a lower side with respect to the clutch hydraulic pressure command value P_target, the communication state between the manual valve 57 and the forward clutch 32 can be accurately determined. Since the command engine output restriction value Rev_lim_target is increased according to the communication state between the manual valve 57 and the forward clutch 32, the transmission torque capacity of the clutch does not become insufficient. Therefore, it is possible to suppress the idling shock caused by the engine 70 being blown, the sudden engagement of the forward clutch 32, and the slippage of the V belt 43.

  In this embodiment, the case where the select lever 51 is changed from the N range to the D range has been described. However, the above control can be performed even when the select lever 51 is changed from the N range to the R range. The above control can also be performed when an L range, an S range, a 2 range, and the like are provided.

  The effect of the embodiment of the present invention will be described.

  When a pulse signal is output from the primary pulley rotation speed sensor 41d, the command engine output restriction value Rev_limi_target is increased at a rate of the restriction release change rate ΔRev_lim. As a result, even when a sensor for detecting the input rotational speed of the clutch is not provided, the communication state between the manual valve 57 and the forward clutch 32 can be accurately determined, and the engine output can be regulated accurately. Therefore, idling of the engine 70, clutch engagement shock, and slipping of the V-belt 32 can be suppressed (corresponding to claim 1).

  If it is determined by the inhibitor switch 56 that the select lever 51 has been changed from the N range to the D range, the command engine output restriction value Rev_lim_target is set to a reference output restriction value Rev_lim that is an engine rotation speed equivalent to an idle, whereby the engine 70 It is possible to suppress idling, clutch engagement shock, and slip of the V-belt 32 (corresponding to claim 2).

  When a pulse signal is output from the primary pulley rotation speed sensor, the command engine output restriction value Rev_limi_target is increased at a rate of the restriction release change rate ΔRev_lim, so that the engine rotation speed rapidly increases even after the forward clutch 32 starts to be engaged. Ascent, clutch engagement shock, and slip of the V-belt 32 can be suppressed (corresponding to claim 3).

It is a schematic block diagram of the V belt type continuously variable transmission of embodiment of this invention. It is a schematic block diagram which shows the structure of the transmission of embodiment of this invention. It is a flowchart explaining clutch oil pressure control of the embodiment of the present invention. It is a flowchart explaining the engine output restriction | limiting control of embodiment of this invention. It is a time chart which shows the change of the engine speed when not using this invention. It is a time chart which shows the change of the engine speed at the time of using this invention.

Explanation of symbols

10 Hydraulic pump 14 Clutch pressure adjusting device (hydraulic control means)
20 Torque converter 30 Forward / reverse switching clutch 32 Forward clutch 33 Reverse brake 41 Primary pulley 41d Primary pulley rotational speed sensor (primary pulley rotational speed detecting means)
42 Secondary pulley 43 V belt 56 Inhibitor switch 57 Manual valve 60 Control unit

Claims (2)

In a continuously variable transmission control device that controls a continuously variable transmission including a belt that is wound around a primary pulley and a secondary pulley, and a contact radius of the pulley changes according to a groove width.
An inhibitor switch that outputs a signal according to the select lever operating position;
A manual valve that is displaced according to the operation position of the select lever and supplies hydraulic pressure to one of a forward clutch or a reverse clutch interposed between the primary pulley and the engine;
Hydraulic control means for controlling the hydraulic pressure supplied to the forward clutch or the reverse clutch based on the output signal of the inhibitor switch and the driving state of the vehicle;
Primary pulley rotation speed detection means for detecting the rotation speed of the primary pulley;
Engine output regulating means for regulating engine output when it is determined that the select lever operating position is switched from the non-traveling position to the traveling position based on the output signal of the inhibitor switch;
A continuously variable transmission comprising: engine output restriction release means for releasing restriction of the engine output when a pulse signal is output from the primary pulley rotation speed detection means after the engine output is restricted; Machine control device.   2. The continuously variable transmission control device according to claim 1, wherein the engine output restricting means sets the engine rotation speed to a rotation speed equivalent to an idle.