JPH1137261A - Operating oil pressure controller of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform selection from the neutral range to the drive range in selecting in a short time without shock. SOLUTION: An operating oil pressure controller is provided with a precharge pressure adjusting means for forming precharging rack pressure to a starting friction clamping element by suddenly lowering operating oil pressure after temporarily and suddenly raising it when selection is performed from the neutral range to the drive range, and a capacity adjusting pressure adjusting means for forming capacity adjusting pressure of the starting friction fastening element by gradually raising operating oil pressure from the lowering time of precharge pressure. The operating oil pressure Pv (Pv1, Pv2) in the lowering time of precharge pressure by the precharge pressure adjusting means and the rising speed θt (θt1, θt2) of the operating oil pressure by the capacity adjusting pressure adjusting means are changed according to the braking state of a vehicle on which an automatic transmission is loaded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating hydraulic pressure control device for an automatic transmission, and more particularly to an operating hydraulic pressure control device for an automatic transmission that reduces a select shock when the driving range is selected from a neutral range. About.

[0002]

2. Description of the Related Art Conventionally, as an operating hydraulic pressure control device for such an automatic transmission, one disclosed in Japanese Patent Application Laid-Open No. 3-28571 is known.

In this system, when switching from a neutral range to a driving range by inputting a range signal, the operating oil pressure is temporarily increased suddenly, and then the operating oil pressure is suddenly decreased to generate a precharge shelf pressure for precharge. Means, and a capacity adjusting pressure adjusting means for gradually increasing the operating oil pressure from the time of the decrease of the precharge pressure to create a capacity adjusting pressure of the friction engagement element. After the working oil pressure is suddenly increased by the charge pressure adjusting means and then rapidly lowered, the preparation for fastening the friction engagement element is quickly performed, and then the operating oil pressure is gradually increased by the capacity adjusting pressure adjusting means. By reducing the shock when the frictional engagement element is completely engaged, it is possible to achieve both the completion of the selection in a short time and the reduction of the shock. To have.

[0004]

However, in such a conventional operating hydraulic control apparatus for an automatic transmission, the setting of the above-mentioned shelf pressure at the time of selection and the subsequent gradual increase of the operating hydraulic pressure are performed by the automatic transmission. Is set uniquely regardless of the state of the brake of the vehicle equipped with, for example, whether or not the brake is operated, so that the selection (shifting) can be completed in a short time and the shock can be reduced at the same time. However, there is a problem that the case where is not sufficiently satisfied occurs. That is, although the degree of the shock transmitted to the vehicle is different between the state where the brake is operated and the state where the brake is not operated, the degree of the shock is transmitted without considering the degree of the shock. And the reduction of shock are not sufficiently satisfied.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem, and to select a shift from a neutral range to a drive range in a short time and in a short time in both operation and non-operation of a brake. It is an object of the present invention to provide an operating hydraulic pressure control device for an automatic transmission, which can be performed without any problem.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, when the operating range is selected from the neutral range to the driving range, the operating hydraulic pressure is temporarily increased and then rapidly lowered. Precharge pressure adjusting means for producing a precharge shelf pressure to the starting frictional engagement element, and gradually increasing the operating oil pressure from the time when the precharge pressure decreases to adjust the capacity of the starting frictional engagement element. A hydraulic pressure control device for an automatic transmission, comprising: a pressure adjusting means for generating pressure; and a brake state determining means for determining a brake state of a vehicle equipped with the automatic transmission; The operating oil pressure at least at the time when the precharge pressure is decreased by the precharge pressure adjusting means is changed in accordance with the determination made by the precharge pressure adjusting means. To.

Further, according to a second aspect of the present invention, in the first aspect of the present invention, the operating oil pressure at the time when the precharge pressure falls when the brake operation state is determined by the brake state determining means is reduced. The hydraulic pressure is higher than the operating oil pressure when the brake is not operating.

According to a third aspect of the present invention, when the driving range is selected from the neutral range, the operating oil pressure is temporarily increased and then rapidly decreased to reduce the precharge shelf pressure to the starting frictional engagement element. Automatic pre-charge pressure adjusting means, and capacity adjusting pressure adjusting means for gradually increasing the operating oil pressure from the time of the decrease of the pre-charge pressure to create a capacity adjusting pressure of the starting frictional engagement element. In the hydraulic pressure control device for a transmission, brake state determining means for determining a brake state of a vehicle on which the automatic transmission is mounted is provided, and the capacity adjusting pressure adjusting means is provided in accordance with the determination by the brake state determining means. The rate of increase of the working oil pressure from the point of time when the precharge pressure decreases is changed.

Further, according to a fourth aspect of the present invention, in the third aspect of the invention, when the brake operating state is determined by the brake state determining means to be in a brake operating state, the increasing speed of the operating oil pressure is in a brake inoperative state. In this case, the operating speed is higher than the rising speed of the operating oil pressure.

According to the first aspect of the present invention, the brake state of the vehicle equipped with the automatic transmission is judged by the brake state judging means, and the precharge pressure is adjusted by the precharge pressure adjusting means in accordance with the judgment. The working oil pressure at least at the time of falling is changed. Therefore, even if the state of the brake changes, the operating oil pressure at least at the time of the decrease of the precharge pressure by the precharge pressure adjusting means is changed correspondingly, so that the friction engagement element is not affected without a large shock. Preparations for fastening can be made.

According to the second aspect of the present invention, the operating oil pressure at the time when the precharge pressure drops when the brake state is determined by the brake state determining means is the operating pressure when the brake is not operating. Since the pressure is higher than the oil pressure, the preparation of the engagement of the friction engagement element can be performed more quickly during the brake operation state than when the brake is not operating.

According to the third aspect of the invention, the brake state of the vehicle equipped with the automatic transmission is determined by the brake state determining means, and the precharge pressure adjusting means determines the brake state in accordance with the determination. The rate at which the operating oil pressure rises from the time when the charge pressure falls is changed. Therefore, even if the state of the brake changes, the increasing speed of the working oil pressure from the time point of the decrease of the precharge pressure by the capacity adjusting pressure adjusting means is changed correspondingly, without causing a large shock. In addition, fastening of the friction fastening element can be performed.

According to the fourth aspect of the present invention, the rate of increase of the operating oil pressure when the brake state is determined by the brake state determining means is higher than the rate of increase of the operating oil pressure when the brake is not operating. Therefore, the frictional engagement element can be fastened in the brake operating state more quickly than in the brake non-operating state. Conversely, when the brake is not operating, the operating oil pressure rises at a low speed, so that a large shock does not occur.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the embodiments illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For example, features illustrated or described as part of one embodiment, can be used on another embodiment to yield a still further embodiment. Note that the same reference numerals are used for the same functional parts throughout the description and the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, wherein 1 is an automatic transmission, 2 is an engine, and the automatic transmission 1 has a gear train including a plurality of sets of planetary gear devices as is well known. The output rotation of the engine 2 is input to the gear train via the torque converter 3.
That is, the turbine of the torque converter 3 is connected to the input shaft of the automatic transmission 1, and the pump impeller of the torque converter 3 is connected to the output shaft of the engine 2.

The gear train of the automatic transmission 1 is the same as that described in Japanese Patent Laid-Open No. 3-28571.
A combination of ON and OFF switching of the first shift solenoid 42 and the second shift solenoid 44 is used to perform a combination of engagement and release of each friction engagement element, so that various speeds can be obtained. Incidentally, the starting frictional engagement element according to the present invention corresponds to a forward clutch in the drive range and a reverse clutch in the reverse range.

Reference numeral 10 denotes a control unit constituted by a microcomputer or the like. The switching signal of the first shift solenoid 42 and the second shift solenoid 44 is outputted from a shift control means 200 provided in the control unit 10. The shift determination at this time is based on a predetermined shift schedule using the throttle opening signal obtained from the throttle sensor 202 for detecting the throttle valve opening of the engine and the vehicle speed signal obtained from the vehicle speed sensor 204 as parameters. It is performed based on.

Reference numeral 24 denotes a line pressure solenoid. The line pressure solenoid 24 is constituted by, for example, an on-drain type solenoid valve.
The line pressure is controlled by controlling the duty of the line 4. Thus, the line pressure solenoid 24 is driven by a control signal output from the line pressure control means 206 included in the control unit 10, and normally outputs a signal corresponding to the throttle opening.

Here, in this embodiment, the precharge pressure adjusting means 210 and the capacity adjusting pressure adjusting means 212 are formed in the control unit 10.
With 212, line pressure control is performed when a neutral (N) range is selected to a driving (D, R) range, for example, a neutral (N) range is selected to a driving (D) range.

That is, the precharge pressure adjusting means 210
Detects, for example, a signal selected from a neutral range to a drive range from a neutral range from a range switch signal generated when the selection lever 214 is operated, and a brake state determination unit 216 described later.
The control signal is output to the line pressure control means 206 in accordance with the result of the judgment of (1), and the line pressure is temporarily increased and then controlled to be decreased rapidly.

The brake state determining means 216 includes, for example,
According to the depressing operation of the brake pedal 4 of the vehicle, "O
The state of the brake switch 5 that is "N" or "OFF" can be detected. Also,
According to the operation of the side (hand) brake of the vehicle, "O"
The state of the side brake switch that is turned “N” or “OFF” may be detected.

As shown in FIG. 2, the line pressure regulated through the pre-charge pressure regulating means 210 is rapidly increased to a constant shelf pressure Pc at the same time as switching from the N range to the D range. After the shelf pressure Pc has been continued for a predetermined time Tc,
The pressure is rapidly dropped to a predetermined pressure Pv according to the result of the determination by the brake state determining means 216. The shelf pressure Pc is precharged to the forward clutch, which is a starting frictional engagement element that is engaged when switching from the N range to the D range.

On the other hand, the capacity adjustment pressure adjusting means 212 receives a precharge end signal from the precharge pressure adjusting means 210 and receives a signal from the brake state determination means 216 to send a control signal to the line pressure control means 206. Output,
In accordance with the result of the determination by the brake state determination means 216, the control is performed so as to change the line pressure increasing speed and increase the line pressure.

That is, as shown in FIG. 2, the line pressure controlled by the capacity adjusting pressure adjusting means 212 is determined by the brake state determining means 216 after a lapse of a predetermined time Tc from the switching from the N range to the D range. From the predetermined pressure Pv corresponding to the control time Ts until the forward clutch is completely engaged, and at a predetermined speed according to the determination result of the brake state determination means 216.

An example of a control procedure executed by the precharge pressure adjusting means 210 and the capacity adjusting pressure adjusting means 212 will be described with reference to a flowchart shown in FIG. This is performed every predetermined time.

First, in step S1, it is determined whether or not the current range position is in the N range. If "YES", the flow advances to step S2 to set a flag F to "0". Then, the process proceeds to step S3, where the precharge pressure adjusting means 21
A predetermined time Tc is set in a timer 1 provided at 0, and a predetermined time Ts is set in a timer 2 provided in the capacity adjusting pressure adjusting means 212. Further, the process proceeds to step S4, and the normal line pressure control is set.

The timers 1 and 2 are decremented (-1) at regular intervals, and are stopped when they become zero.

On the other hand, if "NO" is determined in the step S1, it is determined that the range has been selected from the N range to the D range, and the process proceeds to a step S5 to determine whether or not the timer 2 set in the step S3 has become 0. That is,
It is determined whether the engagement control time Ts has elapsed. "Y
In the case of "ES", it means that the engagement control of the starting frictional engagement element has been completed, and the process proceeds to step S4 to set the normal line pressure control.

If "NO" is determined in the step S5, the process shifts to the line pressure transient control.
Whether timer 1 has reached 0 in 6, that is,
It is determined whether or not a predetermined time Tc of the precharge has elapsed. If “NO”, the process proceeds to step S8. And
In step S8, the brake switch 5 is turned "ON".
Or “OFF”. Here, in the case of “NO”, it is determined that the brake is in the non-operating state, and step S1 is performed.
Proceeding to 2, the line pressure PL is set so as to be the precharge shelf pressure Pc1. On the other hand, in the case of “YES”, it is determined that the brake is in the non-operation state, and step S11 is performed.
And the line pressure PL is set so as to be a precharge shelf pressure Pc2 higher than Pc1.

On the other hand, if "YES" is determined in the step S6, that is, the predetermined time Tc of the precharge,
Is completed, the process proceeds to step S7 to determine whether or not the flag F is 1. If "NO", the step S9 is carried out.
And the brake switch 5 is turned "ON" or "OFF".
Is determined. Here, in the case of “NO”, as described above, it is determined that the brake is not operating, and the step S
14, the line pressure P at the time when the precharge pressure falls
L is set to a predetermined pressure Pv1. On the other hand, if "YES", it is determined that the brake is in the operating state, and the process proceeds to step S13 to set the line pressure PL to a predetermined pressure Pv2 higher than Pv1. Then, after the above-described steps S13 and S14,
Proceed to steps S17 and S18 to set flag F
Is set to 1 and the routine ends.

On the other hand, if "YES" is determined in the step S7, that is, if the predetermined pressure Pv1 or Pv
If 2 has already been set, the process proceeds to step S10, in which the brake switch 5 is set to "ON" or "ON" to increase the line pressure PL from the predetermined pressure Pv1 or Pv2 at a predetermined speed according to the brake state. OFF ". Here, "N" which is the brake non-operation state
If "O", the process proceeds to step S15, where the line pressure PL
Is increased from a predetermined pressure Pv1 at the time when the precharge pressure falls at a rising speed of the inclination θt1. On the other hand, in the case of “YES” that is the brake operation state, the process proceeds to step S16, in which the line pressure PL is increased from the predetermined pressure Pv2 at the time of the decrease of the precharge pressure at a gradient θt2 greater than the gradient θt1. Set to increase.

Accordingly, in the hydraulic control apparatus for an automatic transmission according to the present embodiment, as shown in FIG. 2, when the line pressure is selected from the N range to the D range and the line pressure is supplied to the forward clutch, When the brake is not operating, first, the hydraulic pressure of the precharge shelf pressure Pc1 is introduced into the forward clutch, and the precharge portion necessary for preparation for engagement of the forward clutch is quickly filled. Since the pressure after filling is set to a lower value Pv1, excessive slippage of the clutch can be prevented without causing a large shock. Further, after the precharge, the line pressure is increased by the gentle rising speed θt1, and the actual fastening is completed in the fastening time (TOFF) without a large shock (shown as SOFF in FIG. 2).

On the other hand, in the brake operation state, first, the hydraulic pressure of the precharge shelf pressure Pc2 higher than Pc1 is introduced into the forward clutch, so that the precharge portion necessary for preparation for engagement of the forward clutch is more quickly charged. Is done. Then, since the pressure after filling is set to a higher value Pv2, excessive slippage of the clutch is prevented. Furthermore, after the precharge, a higher ascending speed θt
Since the line pressure is increased by 1, the time (TON) shorter than the engagement time (TOFF) when the brake is not operated
Is completed. Here, the shock (SON) shown in FIG. 2 is apparently larger than SOFF, but is not so much transmitted to the vehicle at the time of the braking operation, and is actually smaller.

In the above-described embodiment, N
The example in which the range is selected from the driving range is described based on the example of the N to D range.
It goes without saying that the present invention is also applied to the case where the user selects a range.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a time chart for explaining an operation according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating an example of a control procedure according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic transmission 2 Engine 3 Torque converter 10 Control unit 24 Line pressure solenoid 202 Throttle sensor 204 Vehicle speed sensor 210 Precharge pressure adjusting means 212 Capacity adjusting pressure adjusting means 216 Brake state determining means

Claims (4)

[Claims] When a driving range is selected from a neutral range, a precharge pressure adjusting means for temporarily increasing the operating oil pressure and then dropping the operating oil pressure so as to generate a precharge shelf pressure for the starting frictional engagement element, A hydraulic pressure control device for an automatic transmission, comprising: a capacity adjusting pressure adjusting means for gradually increasing the operating oil pressure from a point in time when the precharge pressure decreases to create a capacity adjusting pressure of the starting frictional engagement element. Brake state determination means for determining a brake state of a vehicle equipped with the automatic transmission is provided, and in response to a determination by the brake state determination means, at least a point in time when the precharge pressure is reduced by the precharge pressure adjusting means. An operating hydraulic pressure control device for an automatic transmission, wherein the operating hydraulic pressure is changed. 2. The operating oil pressure at the time when the precharge pressure falls when the brake state determining means determines that the brake is operating, is higher than the operating oil pressure when the brake is not operating. The operating hydraulic control device for an automatic transmission according to claim 1. 3. A precharge pressure adjusting means for temporarily increasing the operating oil pressure and then suddenly decreasing the operating oil pressure when the driving range is selected from the neutral range to produce a precharge shelf pressure for the starting frictional engagement element. A hydraulic pressure control device for an automatic transmission, comprising: a capacity adjusting pressure adjusting means for gradually increasing the operating oil pressure from a point in time when the precharge pressure decreases to create a capacity adjusting pressure of the starting frictional engagement element. Brake state determining means for determining the state of the brake of the vehicle equipped with the automatic transmission is provided, and in response to the determination by the brake state determining means, from the time when the precharge pressure is decreased by the capacity adjusting pressure adjusting means. An operating hydraulic pressure control device for an automatic transmission, wherein a rising speed of the operating oil pressure is changed. 4. The system according to claim 1, wherein the operating speed of the operating oil pressure when the brake operating state is determined by the brake state determining means is higher than the operating speed of the operating oil pressure when the brake is not operating. Item 4. An operating hydraulic control device for an automatic transmission according to item 3.