JPH0694860B2 - Gear shift reduction device for automatic transmission - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift shock reducing device for an automatic transmission with respect to an engine provided in a vehicle or the like.

(Prior Art) An automatic transmission provided in an automobile or the like is configured by combining a torque converter including a pump impeller, a turbine runner, a stator, and the like, and a multistage gear-type transmission mechanism connected to the turbine runner of the torque converter. The ones that have been done are widely used. In such an automatic transmission, a hydraulic control device having a hydraulic circuit section as a main component is usually attached, and the hydraulic control device controls engagement of hydraulically operated friction engagement elements such as clutches and brakes in a transmission mechanism. The combined state is switched, whereby the gear shifting operation is performed.

When the gear shift operation is performed in the automatic transmission, the engine speed changes in accordance with the change in the gear ratio in the automatic transmission, although the vehicle speed hardly changes due to the inertia of the vehicle. A torque fluctuation occurs on the output shaft of the machine, and the acceleration of the vehicle body changes due to the torque fluctuation of the output shaft, which causes a so-called shift shock. As a measure for reducing such a shift shock, for example, the operating hydraulic pressure supplied to the friction engagement element is controlled so that the friction engagement element in the speed change mechanism is smoothly released and fastened. It is conceivable that, however, if this is done, the friction engagement element may be left in the sliding state for a longer period of time, and the friction engagement element may be seized or worn more severely.

Therefore, for example, as disclosed in Japanese Patent Application Laid-Open No. 62-131831, when the shift operation in the automatic transmission is performed, the ignition timing of the engine is retarded to temporarily reduce the engine output. Techniques for reducing shift shock are known.

(Problems to be Solved by the Invention) When the shift shock is reduced by the engine torque reduction control as described above, in the shift of the automatic transmission, the relationship between the vehicle speed and the throttle opening, etc. When the shift condition obtained according to the change in the operating state of is satisfied, a shift signal is output to shift the automatic transmission to a predetermined shift stage, and even if the solenoid valve of the hydraulic system is switched and operated, Depending on the type of shift, it takes different time until the gear is changed, that is, before the shift shock occurs.If the torque reduction control is not performed at the timing corresponding to this, the shift shock increases or the acceleration performance increases. Will be reduced. Also, the degree of occurrence differs depending on the type of shift, that is, the shift-down shift or the shift-up shift.
If the torque reduction control corresponding to this is not performed, it is impossible to effectively reduce the shift shock by minimizing the reduction of the engine output.

However, when the gear shifting operation is continuously performed for a short period of time, the shift shock mitigation control until then is stopped according to the gear shifting signals that are sequentially generated, and the mitigation control according to the gear shifting type by the new gear shifting signal is performed. In either case, it corresponds to the actual occurrence of the shift shock, whether it is performed or the shift shock mitigation control for the previous shift operation is continued when the shift signal continues for a very short period. There is a problem that the controlled control cannot be performed.

That is, for example, when a new shift signal for the 3-2nd gear is generated following the shift signal for downshifting to the 4th-3rd gear and the interval between both signals is relatively long, the shift to the 4th-3rd gear is performed. After the completion, the gear shift is further performed to the second speed, and a two-stage gear shift shock occurs. However, when the interval between both signals is extremely short, the automatic transmission may shift to the shift from the third speed to the second speed by the next shift signal before the shift operation from the fourth speed to the third speed is completed. Become.
At this time, the gear shift shock is small at this stage without being substantially shifted to the third gear, and a gear shift shock occurs in which the gear shifts from the fourth gear to the second gear suddenly. Therefore,
The occurrence timing and magnitude of the shift shock differ depending on the interval of the shift signal, and the shift shock is generated by the shift type of 4-3 speed or 3-2 speed depending on the input order of the shift signal or only the previous shift signal. Accurate mitigation of shift shock cannot be achieved only by shock mitigation control.

Therefore, in view of the above circumstances, the present invention provides a shift shock reducing device for an automatic transmission that appropriately reduces shift shock by controlling engine torque reduction corresponding to continuously generated shift signals. The purpose is.

(Means for Solving the Problems) In order to achieve the above object, a shift shock reducing device for an automatic transmission according to the present invention has a basic configuration shown in FIG.
The automatic transmission B, to which the drive output of the engine A is input, shifts to a predetermined shift stage in response to a shift signal. When shifting the automatic transmission B, the ignition timing of the engine A is retarded. Shock control means C for reducing the engine torque by mitigating the shift shock accompanying the shift operation
To provide.

Further, a shift signal detecting means D for detecting the generation interval of the shift signal of the automatic transmission A is provided, and the signal of this shift signal detecting means D is received and when the shift signal is generated, the shift signal of the previous shift signal is generated. It is determined whether the interval is within the setting range.If it is within the setting range, it is considered that the previous shift has not been substantially performed, and if it is above the setting range, the shift from the shift stage in which the previous shift has been completed is completed. Shift type identification means E to be regarded as
To provide. Then, the control characteristic setting means F which receives the signal from the shift type specifying means E and starts the torque reduction control by the shock control means C with a characteristic different depending on the shift type.
It is configured to include.

(Operation) In the gear shift shock reducing device as described above, regarding the torque reduction control of the engine at the time of gear shifting of the automatic transmission, the control characteristic such as the delay time from the shift signal to the start of the torque reduction control or the torque reduction amount is set. When controlling according to the shift type, the shift signal generation interval is detected by the shift signal detecting means, and when the shift signal is generated, it is determined whether or not the interval from the previous shift signal is within the set range. If it is within the set range, it is regarded as an interlaced shift in which the previous shift has not been substantially performed, and if it is above the set range, it is regarded as a shift from the shift stage in which the previous shift has been completed, and the control characteristic setting means. Thus, the torque reduction control by the shock control means is started with different characteristics depending on the type of shift, and the shift shock is appropriately alleviated.

(Examples) Examples of the present invention will be described below with reference to the drawings. FIG. 2 shows a schematic configuration of a shift shock reducing device for an automatic transmission in an example of a FF type vehicle.

Intake air is supplied to each cylinder 2 of the engine 1 (four cylinders) through an intake passage 4 in which a throttle valve 3 is arranged. The air-fuel mixture supplied into the cylinders 2 is actuated by an ignition system composed of a spark plug 5, a distributor 6, an ignition coil 7, an ignition control unit 8, etc.
The exhaust gas is ignited and burned in a predetermined order in the exhaust passage 9
Is discharged to. Then, the combustion of the air-fuel mixture causes the crankshaft 1a (FIG. 3) as the output shaft of the engine 1 to rotate,
The engine torque obtained from the crankshaft 1a is the automatic transmission 10, the differential gear unit 11, the axle.
It is transmitted to the front wheels 13 (driving wheels) via a power transmission path formed by 12 and the like.

As shown in FIG. 3, the automatic transmission 10 has a torque converter.
14 and a multi-stage gear type speed change mechanism 20, and further, a hydraulic circuit section that forms an operating hydraulic pressure used for controlling the operation thereof.
30 (see Fig. 2) is attached.

The torque converter 14 includes a pump impeller 14a, a turbine runner 14b, a stator 14c, and a case 21, and a crankshaft 1a of the engine 1 to which the pump impeller 14a is connected to a pump drive shaft 16 through an oil pump.
15 are connected. The turbine runner 14b is connected to the speed change mechanism 20 via a hollow turbine shaft 17 and is connected to the crankshaft 1a via a lockup clutch 22, and a one-way clutch is provided between the stator 14c and the case 21. 19, the stator 14c is configured to rotate in the same direction as the pump impeller 14a and the turbine runner 14b.

The speed change mechanism 20 is provided with a planetary gear unit 24 for obtaining a speed change stage of four forward gears and one reverse gear. This planetary gear unit 24 consists of a small sun gear 25 and a large sun gear 2
6, having a long pinion gear 27, a short pinion gear 28 and a ring gear 29. A forward clutch 31 for forward traveling and a coasting clutch 33 are provided in parallel between the small-diameter sun gear 25 and the turbine shaft 17, and the small-diameter sun gear
A one-way clutch 32 is interposed between 25 and the forward clutch 31. Large diameter sun gear 26 and turbine shaft 17
A reverse clutch 35 for reverse traveling is provided between the vehicle and the vehicle, a 2-4 brake 36 is provided, and a 3-4 clutch 38 is provided between the long pinion gear 27 and the turbine shaft 17. ing. The long pinion gear 27 is engaged with and disengaged from the transmission case 42 by a low reverse brake 44 via a carrier 39 and a one-way clutch 41. The ring gear 29 has an output shaft 45.
And the torque of the output shaft 45 is transmitted to the differential gear unit 11 via an idler (not shown) or the like.

In the multi-stage gear type speed change mechanism 20 having the above structure, the forward clutch 31, the coasting clutch 33, the reverse clutch 35, the 2-4 brake 36, the 3-4 clutch 38 and the low reverse brake 44 are appropriately selected and operated. , P range (parking range), R range (reverse range), N range (neutral range), F range (forward range), D range (drive range), 2 range and 1 range It is possible to obtain the first to fourth speeds. Table 1 shows the operating relationships of the clutches 31, 33, 38, 35 and the brakes 36, 44 for obtaining the ranges and the shift stages, and the operating states of the one-way clutches 32, 41 when the ranges and the shift stages are obtained. Shown in.

Each clutch 31,33,38,35 with the operating relationship as shown in Table 1.
The hydraulic pressure that operates the brakes 36 and 44 is formed in the hydraulic circuit unit 30.

Further, an engine control unit 100 and a shift control unit 200 are provided to control the operation of the engine 1 and the automatic transmission 10 as described above.

The engine control unit 100 includes a distributor 6
Speed sensor 51 and crank angle sensor 52 provided in the
Detection signals Sn and Sc representing the engine speed and crank angle obtained from the engine temperature, and detection signals Sw and Sk representing the cooling water temperature Tw and knocking intensity of the engine 1 obtained from the water temperature sensor 53 and the knocking sensor 54 provided in the engine block 1b. , A detection signal St obtained from a throttle opening sensor 55 arranged in association with the throttle valve 3,
The detection signal Sb obtained from the intake negative pressure sensor 56 arranged downstream of the throttle valve 3 in the intake passage 4 is supplied, as well as other detection signals Sx required for controlling the engine 1. .

The engine control unit 100 sets an effective ignition advance value θ that determines the ignition timing based on these various detection signals and the shift retard pulse signal Pj supplied from the transmission control unit 200, and the effective ignition advance value is set. The ignition timing control signal Cq is formed at a timing corresponding to the value θ and is supplied to the ignition control unit 8. As a result, a secondary-side high-voltage pulse is obtained from the ignition coil unit 7 at a timing corresponding to the ignition timing control signal Cq, which is transmitted via the distributor 6 to the spark plug 5
Is supplied to.

The transmission control unit 200 includes detection signals Sw and St obtained from the water temperature sensor 53 and the throttle opening sensor 55,
The detection signal Su obtained from the turbine speed sensor 57, the detection signal Sv obtained from the vehicle speed sensor 58, the detection signal Ss obtained from the shift position sensor 59 according to the range position of the shift lever are supplied, and the automatic transmission 10 Also, a large number of detection signals Sy necessary for the control of are supplied. The transmission control unit 200 forms drive pulse signals Ca, Cb, Cc, Cd (shift signals) on the basis of these various detection signals, and various drive clutch signals Ca, Cb, Cc, Cd built in the speed change mechanism 20 are provided with various clutches 31, 33, 38 ,. 35 and the brakes 36, 44 are selectively supplied to the solenoid valves 61 to 64 for adjusting the hydraulic pressures, respectively, thereby performing the shift control in the automatic transmission 10 and forming the drive pulse signal Ce. The lock-up control in the automatic transmission 10 is performed by selectively supplying the hydraulic pressure to the solenoid valve 65 for switching the supply and discharge of the operating hydraulic pressure to the lock-up clutch 22 built in the hydraulic circuit unit 30. As a result, as shown in Table 1, the various clutches and brakes are selectively put into the engaged state or the released state, the desired shift range and shift stage are obtained, and the lock-up clutch 22 is selectively placed in the engaged state or the released state. It is said that

When performing the above-mentioned shift control, the transmission control unit 200 sets a shift pattern corresponding to the throttle opening Th and the vehicle speed V which are mapped and stored in the built-in memory (see FIG. 4). Shift lines a, b, c, d, e, f
Then, the throttle opening Th represented by the detection signal St and the vehicle speed V represented by the detection signal Sv are collated, and it is determined whether or not a shift condition for upshifting or downshifting is satisfied.

In the shift control by the transmission control unit 200, when the shift operation of the downshift is performed by the automatic transmission 10, the torque fluctuation of the output shaft 45 in the automatic transmission 10 is the torque fluctuation due to the change of the gear ratio. A gear shift shock is caused by a torque fluctuation associated with a change in the output of the engine 1. In order to reduce the gear shift shock by reducing the engine output, the gear shift shock is selected at each shift down shift between the fourth speed and the first speed. The ignition timing is retarded accordingly.

When the shift-down condition is satisfied, the delay angle control delays the supply of the working hydraulic pressure to the friction engagement elements in the speed change mechanism 20 from the time when the shift signal is output, at different times depending on the shift-down type. Taking into consideration, when the period Ta set for each gear type has passed,
The shift retard pulse signal Pj is output to the engine control unit 100.

The specification of the shift type in the retard angle control starts counting for specifying the shift type when the 4th-3rd downshift condition is satisfied and the shift signal is supplied, and the count number CC falls within the set range Tb. When the next shift signal for the 3-2nd or 3-1st shift down is supplied before the corresponding value B (for example, a value equivalent to 100 msec) is reached, the 4-3 downshift is substantially performed. The shift type in this state is specified as the 4-2nd speed or the 4-1st speed downshift, and the period Ta corresponding to this is set. In addition, when the count number CC becomes the value B or more, the next 3-2
When a shift signal for the 3rd or 3rd speed downshift is supplied, it is considered that the shift for the 4th-3rd downshift has been completed, and the shift type in this state is the 3rd-2nd speed or the 3-1st speed.
It is specified as fast downshift, and the period Ta corresponding to this is set.

On the other hand, in the control of the ignition timing by the engine control unit 100, the basic ignition advance value θB is set based on the engine speed and the intake negative pressure, and the transmission control unit 200 outputs the shift retard pulse signal Pj. When supplied, the shift correction value θA for correcting the ignition timing to the side delayed from the reference ignition timing corresponding to the basic ignition advance value θB in order to reduce the shift shock accompanying the shift operation in the automatic transmission 10. When the knocking intensity set by the detection signal Sk is equal to or higher than a predetermined value, a knocking correction for correcting the ignition timing to a delay side from the reference ignition timing corresponding to the basic ignition advance value θB in order to suppress knocking. The value θK is set.

FIG. 5 shows a time chart of the basic control of the shift control and the ignition timing control as described above. First, when the accelerator pedal is depressed at t ₀ point to increase the throttle opening Th and the downshift condition (for example, 4th to 3rd gear) is satisfied at t ₁ point as in A, the period Ta starts from t _1. At the elapsed t ₂ point,
The transmission control unit 200 sends the shift retarding pulse signal Pj to the engine control unit 100, and the engine control unit 100 sets the shift correction value θA to the initial value θa as shown by C.
Is set to. The period during which the friction engagement elements in the transmission mechanism 20 corresponds to a period placed in the semi-engaged state from t ₂ points
Until t _{3 when} Tr elapses, the shift correction value θA is the initial value θa.
Is set, and after the t ₃ point, the value Δθ is gradually increased from the initial value θa.
Each time, the shift correction value θA is set until t ₄ becomes zero, and the basic ignition advance value θB is retarded by the shift correction value θA to set the effective ignition advance value θ, whereby the ignition timing control is performed. Is done.

As a result, the torque R of the output shaft in the automatic transmission 10 slightly increases immediately after the point t ₁ and then decreases as shown by the solid line in FIG. 5D, and then gradually increases after the point t _2. Go. In this case, if the retard correction corresponding to the shift is not performed, as shown by the broken line, the torque R sharply increases after point t ₂ and a shift shock occurs, but the shift correction value θA
By the retard control by the setting of, the increase rate of the torque R after the point t ₂ is reduced, the gear shift operation in the automatic transmission 10 is smoothly performed, and the gear shift shock is alleviated.

Further, FIG. 6 shows a time chart of the ignition timing control with the knocking correction. When the shift condition is satisfied and the shift retard angle pulse signal Pj is transmitted at the point t ₁ ′ as at A, the shift correction value θA is set to the initial value θa as at B, and shift shock reduction control is started. When the engine knocks at a predetermined strength or more at the point t ₂ ′ immediately after, the knocking correction value θK is set according to the knocking strength after the point t ₂ ′ as shown in C. The correction value is set in D as shown by the solid line. That is, the final correction value θR is' from point t ₂ 't ₁ until point is set to the shift correction value .theta.A, in t _2' points after, of large values of the shift correction value .theta.A knocking correction value θK Is set to the value of

As a result, even if the shift correction value θA and the knocking correction value θK are set at the same time, the retard amount is not excessively increased by the sum of the two, as shown by the broken line in FIG. 6D, A situation in which the output of the engine 1 is excessively reduced is avoided. Moreover, the final correction value θR is substantially equal to the shift correction value θA required for the shift shock reduction control,
Knocking correction value θ required for knocking avoidance control
It is assumed to correspond to both K and.

On the other hand, following the shift signal for the 4th-3rd downshift, 3-2
7 to 9 are time charts of the ignition timing control when the speed downshift condition is satisfied. First, in FIG. 7, the 4-3 shift signal is supplied at the point ta, and correspondingly, at the point tb after the period Ta elapses, as in FIG. Is output, the shift correction value θA is set to the initial value θa as in B, and the 4-3 shift shock mitigation control is started. When the next 3-2 shift signal is supplied at a point tc that exceeds the set range Tb from the point ta, a normal shift-down shift that is not an interlaced shift is performed and a 3-2 shift is performed from this point tc. At the point td after the period Ta ′ has elapsed, the shift retard pulse signal Pj is output and the shift correction value θA is set to the initial value θa (the magnitude may be changed), and the 3-2 shift shock mitigation control is performed. Is started.

Further, as shown in FIG. 8, the 4-3 shift signal is supplied at the point ta ', and the period Ta is set in correspondence with this signal.
At the point tb ′ before Ta and the setting range Tb have passed, the following 3
-When the -2 shift signal is supplied, it is regarded as the 4-2 speed interlaced shift in which the 4-3 shift is not substantially performed,
Tc 'when the period Ta "for 4-2 shift has elapsed from this tb' point
At this point, the shift retard pulse signal Pj is output, the shift correction value θA is set to the initial value θa, and the 4-2 shift shock mitigation control is started.

Further, as shown in FIG. 9, the 4-3 shift signal is supplied at the ta ″ point, and the period Ta and the setting range Tb are set correspondingly, but the setting range Tb passes beyond the period Ta. previous
When the next 3-2 shift signal is supplied to the tb ″ point,
At the point tb ″ after the period Ta has elapsed, the shift retard pulse signal Pj is output and the shift correction value θA is set to the initial value θa.
Although the 3rd shift shock alleviation control is started, the 3-2 shift signal before the set range Tb has elapsed is regarded as the 4-2nd interlaced shift in which the 4-3 shift is not substantially performed, At the point td "after the 4-2 shift period Ta" has elapsed from the point tc ", the shift retarding pulse signal Pj is output and the shift correction value θA is set to the initial value θa, so that the 4-2 shift shock is alleviated. Control is started.

In the case of FIG. 7 and FIG. 9 described above, when the next 3-2 shift signal is supplied at the point tc or tc ″,
The gear shift correction value θA set for the 4-3 gear shift shock alleviation performed at that time may be corrected.

The engine control unit 100 and the transmission control unit 200 that perform control as described above are each configured by using a microcomputer, and an example of a program executed by this microcomputer is a flowchart of FIGS. 10 to 12. Will be described with reference to.

The flowchart of FIG. 10 shows a program executed by the transmission control unit 200 during shift control. After control start, various detection signals are fetched in step S1,
In step S2, the throttle opening Th and the vehicle speed V are collated with a shift map which is stored in the built-in memory and represents a shift pattern as shown in FIG.
In S3, it is determined whether or not the downshifting shift condition is satisfied. When YES is determined that the shift condition is satisfied, the count number C and the flag F are set to zero in steps S4 and S5, the shift control program is executed in step S6, a shift signal is output, and the process proceeds to step S7. Step S7
Is for determining whether or not the 4th-3rd downshift condition is satisfied. If this determination is YES and the 4th-3rd shift is set, the count number CC for specifying the shift type is set to zero in step S8. Further, at the time of downshifting other than the 4th-3rd speed, the process directly proceeds to step S11 to add the count number C.

In step S12, it is determined whether or not the flag F is set to 1. It is zero at the time when the shift condition is satisfied, and if NO is determined, the process proceeds to step S13 and 3-2.
It is determined whether the shift is the 3-1 shift or the 3-1 shift, and if it is the 4-3 shift, the NO determination is made in step S15 to determine the period T for the 4-3 shift
Set the value A corresponding to a. Subsequently, the flag F is set to 1 in step S18, and the process proceeds to step S19. In step S19, it is determined whether or not the count number C is equal to or greater than the value A corresponding to the period Ta set in step S15. When the count number C is equal to or greater than the value A, YES is determined in step S20. The angular pulse signal Pj is sent to the engine control unit 100, the flag F and the count number C are set to zero in steps S21 and S22, and the ignition timing retard control is executed to reduce the shift shock.

When the determination in step S19 is NO and the count number C is less than the value A, the process returns to the original step, the NO determination in step S3 proceeds to step S9, the count number CC for gear shift type identification is added, and the subsequent step S10 By the YES judgment of step S11, the addition of the count number C in step S11 is continued, and by the YES judgment of step S12, the process proceeds to step S19 and waits until the judgment becomes YES.

When the 4th-3rd downshift condition is satisfied and the next downshift condition is satisfied, the count C and the flag are determined in steps S4 and S5 in accordance with the YES determination in step S3. F is set to zero, and the NO determination at step S7 determines the count number C at step S11.
Is added. Then, the NO determination is made in step S12, the process proceeds to step S13, and it is determined whether or not the current downshift condition is the 3-2 shift or the 3-1 shift. If the determination in step S13 is YES and the shift is the 3-2 shift or the 3-1 shift, it is determined in step S14 whether or not the count number CC for identifying the shift type is equal to or greater than the value B corresponding to the set range Tb. .

When the determination in step S14 is NO, the shift signal for the next 3-2 speed or 3-1 speed downshift is supplied until the count number CC for specifying the shift type reaches the value B corresponding to the set range Tb. In this case, in step S17, it is regarded as an interlaced shift in which the 4th-3rd downshift is not substantially performed, and the shift type in this state is specified as the 4-2nd or 4-1st downshift, and A value A corresponding to the corresponding period Ta is set. Further, the determination in step S14 is YES.
When the shift signal for the 3-2nd or 3-1st gear downshift is supplied after the count number CC becomes equal to or greater than the value B, the 4th-3rd gearshift down is completed in step S16. Assuming that the shift type in this state is 3-
The shift speed is specified as the 2nd speed or the 3-1st speed downshift, and the value A corresponding to the period Ta corresponding to this is set.

The initial value of the count number CC for identifying the shift type is set to the value B or more, and when the 3-2 shift or the 3-1 shift occurs independently, the determination in step S14 is YES. Leave.

The flowchart of FIG. 11 shows the engine control unit 100.
Shows a program to be executed at the ignition timing control. After the control is started, various detection signals are taken in at step S31, the basic ignition advance value θB is set based on the intake negative pressure and the engine speed at step S32, and step S33 is executed. Determines whether the throttle opening Th is in the load state of the set value TH ₁ or more, and if this determination is YES and it is not the low load state, in step S34 the cooling water temperature Tw is warmed up with the value TW ₁ or more. It is determined whether or not it is in the completed state, and when the determination is YES and the warm-up is completed, it is determined in step S35 whether or not the shift retard pulse signal Pj is supplied. This judgment
If the shift retard pulse signal Pj is supplied in YES, the shift correction value θA is set to the initial value θa in step S37, the retard flag Fr is set to 1 in step S38, and the process proceeds to step S39. After resetting the count number U to zero, the process proceeds to step S41.

In step S41, a knocking correction value θK set in a knocking correction value setting program (FIG. 12), which will be described later, is loaded, and in the following step S42, the gear shift correction value θA and the knocking correction value θK are compared, and the gear shift correction value is compared. If it is determined that θA is greater than the knocking correction value θK, the final correction value θR is set to the gear shift correction value θA in step S43, the process proceeds to step S45, and the knocking correction value θK is shifted in step S42. If it is determined that the correction value θA or more, the final correction value θR is set to the knocking correction value θK in step S44 and the step is performed.
Proceed to S45.

In step S45, the final correction value θR is subtracted from the basic ignition advance value θB to set the execution ignition advance value θ, and in step S46, the effective ignition advance value θ is set based on the crank angle represented by the detection signal Sc. At a corresponding timing, the ignition timing control signal Cq is sent to the ignition control unit 8 and the processing returns to the original.

Also, if the determination in step S33 is NO, the throttle opening Th
Is less than the value TH ₁ , and if the determination in step S34 is NO and it is determined that the cooling water temperature Tw is less than the value TW ₁ ,
After the shift correction value θA is set to zero in step S47 and the retard flag Fr is reset in step S48,
Similarly, perform knocking correction after 41 and return to the original.

On the other hand, if the determination in step S35 is NO, the shift retarding pulse signal Pj
If it is determined that is not supplied, step S5
At 0, it is determined whether or not the retard flag Fr is 1, and when the retard flag Fr is not 1, the routine proceeds to step S47, where the shift correction value θA is made zero. If YES in step S50 and the retard flag is set to 1, after the count number U is added in step S51, the count number U is equal to or larger than the value E corresponding to the period Tr in step S52. Whether or not there is a return timing is determined, and if the NO determination is made, the count number U is equal to the value E.
When it is less than, the process proceeds to step S42 without performing the restoration process. On the other hand, when the determination in step S52 is YES and the period Tr has elapsed, the value Δθ is subtracted from the shift correction value θA to set a new shift correction value θA in step S53, and the shift correction value θA subtracted in step S54 is set. Is less than zero. If it is zero or more, it is as it is, and if it is a negative value, the shift correction value θA is set to zero in step S55, and then the process proceeds to step S56 and the retard flag is set. Fr is reset to zero and the process proceeds to step S42.

Next, the flowchart of FIG. 12 shows a program executed by the engine control unit 100 when setting the knocking correction value. After the control start, the detection signal Sk is captured in step S61, and it is determined in step S62 whether or not the knocking strength represented by the detection signal Sk is equal to or higher than a predetermined value.If the knocking strength is determined to be higher than or equal to the predetermined value, In step S63, a knocking correction value θK according to the knocking intensity is set and the process returns to the original. On the other hand, when the knocking strength is not equal to or higher than the predetermined value, the determination is NO, step S64
In step S65, the value Δθ is subtracted from the knocking correction value θK to set a new knocking correction value θK and advance processing is performed.
Then, it is determined whether or not the knocking correction value θK is less than zero. If the knocking correction value θK is not less than zero, the knocking correction value θK is set to zero in step S66. Return to.

According to the above-described embodiment, the shift-down condition is continuously satisfied when the optimum timing for performing the ignition retard control for reducing the shift shock is changed and controlled according to the shift type. Occasionally, when looking at the occurrence intervals, it is determined whether the shift from the 4-3 shift to the 3-2 speed or the 3-1 shift is substantially the middle shift to the 3rd shift or the non-interlaced shift. With this, it is possible to specify the shift type, accurately set the corresponding period Ta, and appropriately reduce the shift shock.

In the above embodiment, the setting range Tb for determining the interlaced shift is set to be larger than the period Ta that sets the timing for outputting the shift retarding pulse signal Pj, but the magnitude relationship is It is set according to the operating characteristics of the automatic transmission, and may be set so that they are equal or the setting range Tb is small.

Further, in the above embodiment, an example in which the shift type is specified for the case of the 3-2 shift or the 3-1 shift after the 4-3 shift is shown when the downshift condition is satisfied. For shifting between gears as well, the setting range may be appropriately determined to specify the type of shift, and further, if necessary, the shift shock may be alleviated even during upshifting.

(Effect of the Invention) According to the present invention as described above, in performing the torque reduction control of the engine for mitigating the shift shock at the time of shifting the automatic transmission, the delay time from the shift signal to the start of the torque reduction control or When controlling the control characteristics such as the torque reduction amount according to the shift type, the generation interval of the shift signal is detected,
When the shift signal is generated, whether or not the interval from the previous shift signal is within the setting range is determined by the shift type identifying means. If it is within the setting range, it is considered as an interlaced shift, and if it is above the setting range, By considering the shift from the shift stage in which the shift is completed and performing the torque reduction control with different characteristics depending on the type of shift, the shift shock can be appropriately mitigated.

[Brief description of drawings]

FIG. 1 is a functional block diagram for clarifying the configuration of the present invention, FIG. 2 is a schematic configuration diagram of a shift shock reducing device for an automatic transmission in one embodiment, and FIG. 3 shows an internal mechanism of the automatic transmission. Schematic diagram, FIG. 4 is a characteristic diagram showing a shift diagram, FIGS. 5 to 9 are time charts in each control example, and FIGS. 10 to 12 are flowchart diagrams for explaining the processing of the control unit. is there. A, 1 ... Engine, B, 10 ... Automatic transmission, C ... Shock control means, D ... Shift signal detecting means, E ... Shift type specifying means, F ... Control characteristic setting means, 5 ... Spark plug,
20 …… Transmission mechanism, 30 …… Hydraulic circuit section, 100 …… Engine control unit, 200 …… Transmission control unit.

Claims (1)

[Claims] Claim: What is claimed is: 1. An automatic transmission, which shifts to a predetermined shift stage in response to a shift signal, has shock control means for reducing a torque of an engine at the time of shifting to mitigate a shift shock accompanying the shift operation. A shift shock reducing device for an automatic transmission, comprising: a shift signal detecting means for detecting a shift signal generation interval; and a shift signal detecting means for receiving a signal from the shift signal detecting means and a shift signal last time when the shift signal is generated. It is determined whether the interval is within the setting range.If it is within the setting range, it is considered that the previous shift has not been substantially performed, and if it is above the setting range, the shift from the shift stage in which the previous shift has been completed is completed. And a control characteristic setting means for receiving a signal from the shift type specifying means and starting the torque reduction control by the shock control means with different characteristics according to the shift type. Shift shock reducing apparatus for an automatic transmission for.