JPH0235263A - Speed change controller for automatic transmission - Google Patents

Abstract

PURPOSE:To properly carry out the squirt control and reduce shock by changing the kind of the speed change stage which is achieved temporarily according to the fact that the shift from N range to a traveling range is the torque reversal shift or the no-reversal torque shift. CONSTITUTION:When a shift range detecting means detects the N traveling range shift, a torque reversal detecting means judges the torque reversal shift in advance N retreat or retreat N advance or the no-reversal torque shift in advance N advance or retreat N retreat. In the no-reversal torque shift, a squirt control means generates the second speed stage temporarily, while in the case of the torque reversal, the third speed stage in high speed stage is generated. Therefore, the squirt control can be executed with the superior level of the speed change shock and time lag.

Description

[Detailed description of the invention] [Industrial application field]

The present invention is an improvement to a shift control device for an automatic transmission that is configured to reduce shift shock when switching from the N range (neutral range) to the driving range (forward and reverse ranges). Regarding. [Prior Art] Japanese Unexamined Patent Application Publication No. 160658/1983 describes an electronically controlled automatic transmission. In order to reduce the shock during D-shift (shifting from neutral range to drive range), a technology (sufauto control) for temporarily passing through a gear other than the first gear (lowest gear) is disclosed. In addition, Japanese Patent Application Laid-open No. 61-31747 similarly discloses that in order to reduce the shock during R→D shift (shifting from reverse range to forward range), a shift gear other than the first gear is temporarily used. Discloses SF auto control technology. Note that the RD shift can be regarded as an R-jN+D shift in which the holding time in the N range is extremely short. This auto control is performed at a predetermined time after N-1D shift. l (for example, about 0.8 seconds),
A command is issued to engage a frictional engagement device for achieving a gear other than the first gear, and then a command is issued to engage a friction engagement device to achieve a gear other than the first gear. It issues instructions. For example, to explain with reference to the 7j engagement diagram shown in FIG. 4, in the case of a shift from N to D 7j, shifts 1 to 7j would normally be completed by simply engaging the clutch C1, but, In this case, first, clutch C1 and brake B2
The engagement command is issued to temporarily establish the second gear, and then the brake B2 is released to return to the first gear and perform the J operation. In addition, the shock at the time of N->D shift 1- can be alleviated to the extent that the gear ratio does not suddenly change, and it is possible to reduce the so-called auto phenomenon in which the tail portion of the vehicle sinks. Conventionally, the gear stage to be passed through has usually been the second gear stage. Although the shock reduction effect is slightly greater in 3rd gear, there is not much of a difference (not bu, but
On the other hand, if the gear to be passed through is the third gear, there are many operating servos (in the example in Fig. 4, C1, C
2) and B2), there was a fear that the line pressure would drop and the shift time lag would increase.

[Problems to be Solved by the Invention] However, in vehicles where the drive system has relatively large play, especially when the torque is reversed during R→D shift or D→
There is a tendency for the noise and shock associated with rattling to become louder when shifting to R. In this case, for example, by passing through the second gear stage at the time of the R→D shift, there is little effect on countermeasures against the SFO 1~ phenomenon. However, if the 3rd gear is used, the 3rd gear will be routed even during a normal N→D shift (or D→N-+D shift 1) that does not involve torque reversal. Because of this, there was a problem that the shift time lag as shown in (above) may become longer. [Object of the Invention] The present invention has been made in view of such conventional problems, and it is possible to always properly perform auto control, even in a vehicle where the drive system has relatively large play. , N
→An object of the present invention is to provide a shift control device for an automatic transmission that can reduce shock when shifting the driving range. [Means for Solving the Problems] As summarized in FIG. A shift control device for an automatic transmission configured to engage a friction engagement device for achieving a gear position other than the lowest gear position to reduce shock when switching from the N range to the travel range, means for detecting whether the shift from the N range to the travel range is a shift in which torque is reversed;
Means for changing the type of gear stage to be temporarily achieved depending on whether the shift from the range to the driving range is a shift 1~ in which the torque is reversed or a shift in which the torque is not reversed. As a result, the above objectives were achieved. [Operation 1] In the present invention, it is detected whether the shift from the N→driving range is a shift in which the torque is reversed. Whether or not the shift is inverted from 1 to 1 is determined by the relationship between the shift position before and the shift position after the N range. Specifically, when shifted from forward range → N range → reverse range, and when shifted from reverse range → N range → forward range, this corresponds to a shift in which the torque is reversed.In the forward range, D ( drive), 2 (second)
, L (low), etc. are included. On the other hand, the shifts from forward range to N range to forward range and from reverse range to N range to reverse range are shifts without torque reversal. In the present invention, the gear position to be passed through is changed depending on whether the shift from the N to driving range is a shift in which the torque is reversed or a shift in which the torque is not reversed. As a result, for example, when a shift from N to driving range is executed, in which the torque is not reversed, the second gear is passed through, while a so-called R→D shift, or D-)R shift, in which the torque is reversed, is executed. In this case, in order to further reduce the rattling noise and shock caused by the torque reversal, you can choose to have the transmission go through the higher-speed third gear. As a result, when the torque does not reverse from N to driving range shift 1, a shift to 1 with a small time lag is possible, and when the torque reverses from N to driving range, a larger backlash occurs due to the torque reversal. It becomes possible to perform shift 1~ with the hitting noise and shock kept small. [Embodiments] Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings. FIG. 2 schematically shows gears 1 to 2 of a vehicle automatic transmission to which this embodiment is applied. This gear 1 to rain is connected to the front planetary gear mechanism section 1,
It has three sets of planetary gear mechanisms, a rear planetary gear mechanism 2 and an overdrive planetary gear mechanism 3. A sun gear 4 of the front planetary gear mechanism 1 and a sun gear 5 of the rear planetary gear mechanism 2 are connected to each other. or,
The carrier 6 of the front planetary gear mechanism 1 and the ring gear 7 of the rear planetary gear mechanism 2 are connected, and the carrier 6 and ring gear 7 are connected to the carrier 8 of the overdrive planetary gear mechanism 3. On the other hand, a clutch C1 is provided between the turbine shaft 10 connected to the torque converter 9 and the ring gear 11 of the front planetary gear mechanism 1 through the front gear mechanism 1. There is a clutch C between
2 is provided. Further, a brake B1 is provided between the sun gear 4.5 and the transmission case 12, which are connected to each other, and a one-way latch F1 and a brake B2, which are arranged in series, are in a parallel relationship with the brake B1. The transmission case 12 is provided between the sun gear 4.5 and the transmission case 12 so that Furthermore, the carrier 13 of the rear planetary gear mechanism section 2 and the transmission case 1
2, a brake B3 and a one-sided clutch F2 are arranged in parallel. The overdrive planetary gear mechanism 3 has a gear ratio of "11".
A clutch Co and a one-way latch Fo are arranged in parallel between the carrier 8 and the sun gear 14, and a clutch Co and a one-way latch Fo are arranged in parallel between the carrier 8 and the sun gear 14. A brake BO is provided between the case 12 and the case 12. The outputs of the gears 1 to 2 are connected to a counter gear 16 connected to a ring gear 15 of the overdrive planetary gear mechanism 3. The above gear train is used to set the gears by selectively engaging each clutch Co'C2, So to B3 using hydraulic pressure.
This is done by opening up. Figure 3 shows the main parts of the hydraulic control system for this purpose. A manual valve 20 for changing the shift range is mechanically connected to a shift lever (V not shown) on the driver's seat, and is manually operated by the driver to switch between P (parking), R (reverse), and N (neutral). , D (drive), 2 (second), and L (low) shift ranges. The input boat 21 of the manual valve 20 is supplied with line hydraulic pressure that is generated by a hydraulic pump 30 and regulated by a primary regulator valve 40 using a well-known method. In FIG. 3, numeral 50 is a 1-2 shift valve that changes gears between the first and second gears, and 60 is a valve that changes gears between the second and third gears. 2-3 shift valve, 70
1 and 2 respectively show 3-4 shift valves that change gears between the third gear and the fourth gear. Each shift valve 50.6
0.70 spool 5L 61.71 is spring 5
2.62.72 is biased upward in the figure. However, when line hydraulic pressure is supplied to the pilot port 53.63.73 of each shift valve 50, 60.70, each spool 51.61.71 will cause the spring 52.
62.72 and is moved downward in the figure, the movement of each spool 51.61.71 at this time causes each shift valve 50.60.70 to move downward in the figure.
It is formed in such a way that the oil passages can be switched. The pylons 1 to 53, 63, and 73 are connected to output capos 1 to 22 that communicate with the input port 21 when the manual valve 20 is set to the D range, the 2 range, and the forward travel range of the L range. has been done. For this connection, a solenoid valve S1 is interposed and installed in the oil passage 23 leading to the pilot port 63 of the 2-3 shift valve 60. Further, a solenoid valve S2 is interposed and installed in the oil passage 24 leading to the pilot port 53 of the 1-2 shift valve 50 and the pilot port 73 of the 3-4 shift valve 70. These solenoid valves Sl and S2 are in the OFF state when each oil passage 23.
By closing 25.26 to port 1 facing port 24, the line oil pressure supplied to each oil passage 23.24 is maintained as it is, and on the other hand, by opening port 25.26 in the ON state, each oil passage 23.24 It is designed to drain the oil inside. ON-OFF control of the electromagnetic valves S1 and S2 is performed by an ECT (Electronic Control Transmission) control computer, as will be described later. The clutch C1 is connected to the output port 22 of the manual valve 20.
The clutch C2 is also connected to a port 64 to which line hydraulic pressure is supplied when the spool 61 of the 23 shift valves 60 is pushed against the spring 62. Clutch Co is 3-4 shift 1 valve 70
Of each port, the spool 71 is pushed upward in the figure by a spring 72 to a limit position and communicates with a port 74 to which line hydraulic pressure is supplied. Further, the brakes 81 to B3 are communicated with ports 54 to 56 of the 1-2 shift valve 50, and the brake BO is communicated with the port 75 of the 3-4 shift valve 70. With these structures, an appropriate shift range is selected by the manual valve 20, while the solenoid valves Sl and S2 are set to 0N-OFF as shown in FIG. By doing so, the 1st to 4th gear
Gear is achieved. The engagement and release states of the clutches, brakes, etc. at each gear stage are also as shown in FIG. 4. As shown in FIG. 5, the ECT control computer 8
0 is a throttle sensor 8 that detects the throttle opening θ to reflect the engine load (engine torque).
1. Vehicle speed sensor 82 that detects vehicle speed No., N range, D
A shift 1 position sensor 83 for detecting the position of shift 1 to range such as range and P range, a cooling water temperature sensor 84 for detecting the engine cooling water temperature, a brake sensor 85 for detecting that the brake is depressed, Signals such as a pattern select switch 86 are inputted to detect whether the driver selects either driving with emphasis on power performance or driving with emphasis on fuel economy. The ECT control computer 80 obtains these input signals and drives the electromagnetic valves S1 and S2 in the hydraulic control device described above according to the speed change map of the throttle opening and vehicle speed, as in the conventional case, to shift to the first gear. ~Execute shift control for the fourth gear. When a shift from N to D is performed, if SAF auto control is not performed, clutch C is used to directly establish the first gear.
Hydraulic pressure is supplied only to 1. However, when the auto control is executed, an engagement command to a higher speed gear (second gear or third gear) is issued, and then a command to the first gear is issued. A flowchart of this automatic control is shown in FIG. 6 below. In this flowchart, when shifting from D-)N to D (D is outside the drive range and includes forward ranges such as second (S) and low (L)), the second gear is passed through for the To time. Auto control is executed. At the time of R-+N-+D shift, auto control is executed to cause the vehicle to go through the third gear for the TR time. Let's start with a detailed explanation of the flow. In step 101, each flag Fo to F3 and timers T1 and T2 are reset as initialization. Here, the flag Fo is a flag that is set to 1 when the N-)D shift is executed, and is set to 0 otherwise. The flag F1 is a flag that becomes 1 when the N→R shift is executed, and becomes 0 otherwise. The flag F2 is set to 1 when the transition to the second gear is executed;
This is a flag that becomes zero when this is not the case. The flag F3 is set to 1 when the transition to the third gear is executed.
This is a flag that becomes zero when this is not the case. The timer T1 is an automatic timer that starts counting when the shift to the second gear is executed. The timer T2 is a timer 1 to 1 that starts counting when the shift to the third speed is executed. In step 102, the gear position is determined from the vehicle speed and throttle opening as in the conventional main routine. In step 103, flag Fo is determined. In the case of Fo-0 where the N-+D shift has not been executed, the process proceeds to step 104, where it is determined whether the N-+D shift has been executed. If the N→D shift is executed, the flag Fo is set to 1 (step 105),
If the N-+D shift is not to be executed, the process proceeds to step 106 and it is determined whether the N-JR shift is to be executed. If there is an N→R shift, it does not indicate that the N→R shift has been executed and Fl is set to 1 (step 107).
. If the N→D shift execution flag Fo is set to 1, the steps from step 103 to step 10'8 are performed after returning.
flows to. Here, a flag F1 indicating that the N→R shift has been executed is determined. When Fl is zero, that is, before N-+D shift (','Fo=1
) If N-R shift is not performed (D-JN-+D
In this case), the flow goes to step 109). Step 1
In step 09, flag F2 is determined. When the flag F2 is zero, that is, when it is determined that the instruction to the second gear in the D-+N → D shift has not been issued yet, the process proceeds to step 110, where the instruction to the second gear is issued and the shift The automatic timer T1 is started (step 111), and the execution flag F2 for passing to the second gear is set (step 112). Once F2-1 is activated, step 109 is changed to step 1.
It will flow to 13. Here, the automatic timer T1 and the predetermined value To are compared. If T+<To, nothing is done and the process returns as is. If T1≧TO, the system instructs to return to the first gear (step 114), resets each flag Fo, Fl, and F2 to 1 (step 115), and resets the auto timer T1. (Step 116). As a result, in the case of a D→N→D shift, that is, in the case of a non-reversal shift from 1 to 1000 lux, the automatic control is executed to achieve the second gear only during To. , in the case of R→N−+D shift (flag F1
becomes 1, then the flag Fo becomes 1), then
Since it is Fl-1, steps 108 to 117
flows to. Here, flag F3 is determined. F3-
0. In other words, if the R→N→D shift is before the execution of the third gear, the third gear is instructed (step 118).
, the automatic timer T2 starts counting (step 119), and a flag F3 indicating that the transit to the third gear has been executed is set to 1 (step 120). Once flag F3=1, the flow starts from step 117 to step 121. Here, the auto timer T2 is compared with a predetermined value TR, and if 'T+<TR, the process returns without any response, and when T1 is above TR, a return to the first gear is instructed (step 122). , each flag F., F+, F3 is reset (step 123>), and the auto timer T2 is reset (step 1
24). As a result, when the R-+N-1D shift is performed, that is, when the shift in which the torque is reversed is performed, the auto control that goes through the third gear only during the TR is executed. According to this control flow, the torque does not reverse D−)N
- When the D shift is executed, as in the past, the second gear is shifted to the second gear for a predetermined period of time. On the other hand, when the R→N→D shift 1-, in which the torque is reversed, is executed, a quick auto control is executed in which the third gear is passed only for a predetermined time TR.This reduces the output shaft torque to a low level. This makes it possible to reduce the rattling noise and shock in the drive system caused by sudden torque reversals.As is clear from Fig. 4, the clutch C2 is
It is designed to be activated during gear and reverse gears. Therefore, when the R → N-D shift is performed in a short period of time, the hydraulic pressure supplied in the reverse gear remains in the clutch C2, so the shift can be started without causing a drop in the hydraulic pressure due to the operation of the servo system. It is possible to achieve 3rd gear. Therefore, the time lag does not become large, and the rattling noise is also reduced to a greater extent than when the second gear is used. In addition, the reason why the SAF auto timer (time passing through high speed gear) is changed between D→N-+0976 and R→N→D shift is because clutch C is changed during R-+N-D shift.
2 continues to be supplied, it takes a long time to return to the first gear, so this is to enable the return to the first gear to be started sooner. In addition, in this embodiment, since the reverse stage is one stage, the D-+N-+R shift is not particularly mentioned in flowcharts 1 to 6 in FIG. Regarding D-+N-R shift 1~, R→N→
It is obvious that it can be considered in the same way as the D shift. In addition, in the gear train of this embodiment, for example, the high-speed reverse stage engages clutches C2, BO, and B3, and clutch C. This can be achieved by opening the . In this case, if D-+N→R shift 1, where the torque is reversed, is executed, the high-speed reverse stage is executed, and if shift 1~, where the torque is not reversed, such as R->N-R, is executed, It is also possible to configure the system so that it does not go through the high-speed reverse stage. [Effects of the Invention] As explained above, according to the present invention, when the torque is reversed from N to the driving range shift, and when the torque is not reversed from N
→Since the high-speed gear to be passed through is changed when the driving range is shifted, it is possible to always perform automatic control at a level that does not cause problems with shock or time lag during gear shifting. You can get the same effect.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the gist of the present invention, and FIG. 2 is a block diagram showing the gist of the present invention.
A skeleton diagram of a gear train of an automatic transmission for a vehicle to which an embodiment of the present invention is applied, FIG. 3 is a hydraulic circuit diagram showing the main parts of the hydraulic control device of the automatic transmission, and FIG. 4 is a diagram of each shift. A line diagram showing the switching state of the solenoid valve and the engagement/action state of the frictional engagement device when achieving the range; Fig. 5 is a block diagram showing the input/output relationship of the ECT control computer; Fig. 6 is , is a flowchart showing a control procedure executed by the apparatus of the embodiment. 80... ECT control computer, 81... Throttle sensor, 82... Vehicle speed sensor, 83... Shift position sensor, Sl, $2... Solenoid valve, T1... SF auto timer, T2 ...Sufauto timer, TO, TR...predetermined time (time to pass through high speed stage)
.

Claims (1)

[Claims] (1) A means for detecting a shift range is provided, and when the shift range is switched from the N range to the driving range,
A shift control device for an automatic transmission configured to temporarily engage a frictional engagement device to achieve a gear other than the lowest gear to reduce shock when switching from the N range to the driving range. means for detecting whether or not the shift from the N range to the drive range is a shift in which torque is reversed; and when the shift from the N range to the drive range is a shift in which torque is reversed; . A shift control device for an automatic transmission, comprising: means for changing the type of gear stage that is temporarily achieved depending on a shift that does not reverse.