JPH0477183B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention can be applied to a control device that switches gears in an auxiliary transmission mechanism of an automatic transmission, and in particular, the invention can be applied to a control device that switches gears in an auxiliary transmission mechanism of an automatic transmission. It relates to a mechanism control device. (Prior Art) Conventionally, gear changes (shift control) in automatic transmissions for automobiles have been performed using a hydraulic circuit using a large number of valves to engage and release multiple hydraulic friction elements that make up an auxiliary transmission mechanism. This is done by controlling the movement. An example of such a conventional device is the one described in Japanese Patent Application Laid-Open No. 196352/1983, for example. (Problems to be Solved by the Invention) However, the above conventional device uses multiple control devices such as orifices and accumulators for each oil passage in order to adjust the timing of changing the oil pressure of each friction element during gear shifting. Because the hydraulic circuit is interposed in the middle, the hydraulic circuit becomes complicated, and the hydraulic pressure may change due to changes in operating conditions (for example, shifting during slow acceleration or shifting during sudden acceleration, etc.) or changes in oil temperature. Although it is necessary to finely adjust the timing of replacement, such adjustments could not be made properly. (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention deals with friction elements for gear shifting that are engaged during gear shifting, which constitute the auxiliary gear shifting mechanism of an automatic transmission. hand,
It is equipped with an output hydraulic pressure control means that uses a pressure control valve that can freely change the output hydraulic pressure to change the hydraulic pressure from an appropriate engagement start hydraulic pressure to a complete engagement hydraulic pressure, An oil passage switching valve that has an output hydraulic pressure supply passage, a line pressure supply passage, and a drain passage, and switches the oil passage so as to connect any one of these to the oil passage communicating with the friction element. and a switching valve control means for controlling switching of the oil passage switching valve, and when shifting, the switching valve controlling means controls an oil passage communicating with one of the friction elements that is fastened during shifting. For,
From the start of engagement to complete engagement, connect the output hydraulic pressure supply path from the pressure control valve, and when maintaining the engagement during the next gear shift, connect to the line pressure supply path to maintain the engagement; The switching of the oil passage switching valve is controlled so that the drain passage is connected when the oil passage switching valve is opened. (Function) During gear shifting, hydraulic pressure that changes from the appropriate engagement starting hydraulic pressure to the complete engagement hydraulic pressure is supplied to the friction element that is engaged, thereby preventing changes in operating conditions, oil temperature, etc. Accordingly, the engagement operation of the friction element can be appropriately controlled, and in particular, the effect of reducing the shift shock can be obtained. In addition, for friction elements that remain engaged during gear shifting, the connected oil path is switched to a line pressure supply path to maintain engagement, so the newly engaged friction element can be engaged while reducing shift shock. In addition, since unnecessary opening and re-engagement of friction elements that should be kept engaged can be prevented, the shift shock reduction function, which is important for automatic transmissions, can be maximized. (Embodiment) FIG. 1 shows the configuration of an embodiment of the present invention. The auxiliary transmission mechanism of the automatic transmission to be controlled by this embodiment device is the same as that described in the L4N71B type and E4N71B type maintenance manual published by Nissan Motor Co., Ltd. (November 1981). can be,
OD brake B ₁ , second brake B ₂ , rear clutch C ₁ , front clutch shown in Fig. 1
In addition to hydraulic friction elements such as C ₂ , direct clutch C ₃ , and low/reverse brake C ₄ , the torque converter 1 is equipped with a planetary gear and a one-way clutch (not shown), and by switching the engagement/disengagement combination of each friction element. Shifts the engine output obtained through the The device of this embodiment is a device for controlling the hydraulic pressure applied to each of the friction elements, and is composed of a hydraulic circuit and an electrical control circuit shown in FIG. 1. The line pressure supplied to the hydraulic circuit is controlled by the throttle pressure determined by the cutback solenoid 4 and the vacuum throttle valve 5, so that the discharge pressure of the oil pump 2 reaches a specified level at the pressure regulator valve 3. Oil line 1 adjusted to pressure
1. The line pressure supplied through the oil passage 11 is supplied via the oil passage 12 to the input port 61a of the rotary valve 60 as an oil passage switching valve. This rotary valve 60 has three output ports 61a to 61d in addition to the input port 61b.
and another input port 61e, the output port 61b is connected to the rear clutch C ₁ via the oil passage 16, the output port 61c is connected to the second brake B ₂ via the oil passage 17, and the output port 61
d is connected to the front clutch _C2 via an oil passage 15. The input port 61e communicates with the pressure control valve 30 via the oil passage 14. Oil passages 18 and 19 connect direct clutch C ₃ and OD brake B ₁ to oil passage 11 for supplying line pressure.
A directional control valve 7 is inserted in the oil passage 2 which connects the low reverse brake C ₄ to the oil passage 11.
0, a directional switching valve 8 is inserted. One directional control valve 7 is a direct clutch.
It is a 4-way 2-position solenoid valve that selectively engages C ₃ and OD brake B ₁ , and the other directional control valve 8 is a low/reverse brake C ₄
This is a 2-way, 2-position solenoid valve that engages and releases the valve. The internal structure of the rotary valve 60 is the second
As shown in the longitudinal cross-sectional view in the figure, a rotary spool 71 is housed inside a cylindrical valve housing 70. This rotating spool 71 is
The two input ports 61a and 61e and the three output ports 61b to 61d are divided into five valve parts 81 to 85, and these valve parts 8
1 to 85 are configured to rotate together by the rotation of a shaft portion 72 protruding from the lower end of the rotary spool 71. The valve housing 70 is the transmission case 2
01, and the valve housing 70
The step motor 62 and the step motor 62 are integrated by a mounting bracket 73. And the step motor 62
The rotating shaft 62a and the shaft portion 72 are connected to the pin 7.
4, and the rotating spool 71
is rotated by a step motor 62. Furthermore, −, −, −, in Fig. 2
The cross sections of the valve parts 81 to 85 taken along lines - and - are shown in order in FIGS. 3 to 7. Here, for the sake of distinction, the valve parts 81 to 85 are referred to as a first stage valve part to a fifth stage valve part from the top in FIG. As shown in FIG. 3, the first stage valve section 81 is
The inner circumference 70A of the valve housing 70 is placed around the entire circumference of the valve housing 70.
A space 101 is provided between the two, and a through hole 111 is provided in the diametrical direction. As shown in FIGS. 4 to 6, the second to fourth stage valve sections 82 to 84 are spaces 141 to 153, respectively, partitioned by vanes 121 to 134 protruding from predetermined positions on the outer periphery. is formed. In the diametrical direction of each of the valve parts 82 to 84, there are through holes 1 at positions shifted by a predetermined angle from each other.
12 to 114 are formed. The fifth stage valve section 85, as shown in FIG.
A space 102 is provided around the entire circumference, and a through hole 115 is formed in the diametrical direction. Further, detour paths 91 passing through the inside of the valve housing 70 are provided at positions corresponding to the valve portions 81 to 85 of each stage.
~95 are formed, and these detours 91~
95 communicates with each of the input/output ports 61a to 61d, and opens at a position symmetrical to the opening positions of these input/output ports with the rotation axis of the rotary spool 71 in between. Furthermore, two parallel drain passages 78,
79 is formed, and the first stage valve part 8
A line pressure supply path 75 is formed through the center of the first and second stage valve sections 82, and a fastening hydraulic pressure supply path 77 is formed through the center of the third to fifth stage valve sections 83 to 85. There is. These line pressure supply paths 75
and the fastening hydraulic pressure supply path 77 are separated from each other by a partition wall 76, as shown in FIG. Inside the second to fifth stage valve sections 82 to 85, there is a space 143 of the second stage valve section 82 and a space 143 of the second stage valve section 82.
47 to the through hole 115 of the fifth stage valve portion 85 are formed through the hydraulic pressure supply paths 160 and 161. Next, a specific configuration example of the pressure control valve 30 is shown in FIG. The pressure control valve 30 includes a proportional solenoid 301 driven by a control current _S3 from the controller 50 as an output hydraulic pressure control means and a switching valve control means.
The tip of the plunger rod 301a is in contact with the top of the pilot valve 302. Main spool 30 for adjusting output oil pressure
3 includes a damper orifice 303a and is biased by a return spring 307. The hydraulic oil flowing in from the oil passage 13 (connected to the position opposite to the oil passage 14) has a load proportional to the initial setting load of the return spring 306 for the pilot valve and the control current value given to the proportional solenoid 301. The main spool 303 is moved to adjust the pressure so that the set pressure is thus determined, and the oil flows out from the oil passage 14. Note that the pressure control valve used here is not limited to the output control valve 30 shown in FIG. 8 above, and for example, the pressure control valve 4 shown in FIG.
0 can also be used. This pressure control valve 40 includes a proportional solenoid 401 driven by a control current _S3 from a controller 50, and the tip of a plunger rod 401a of this proportional solenoid 401 is in contact with a diaphragm partition wall 410. The diaphragm partition wall 401 is connected to the spool valve 4
03, and the spool valve 403 moves with the displacement of the plunger rod 401a. The spool valve 403 is connected to the pilot chamber 409.
The hydraulic pressure applied to the proportional solenoid 401 is displaced so as to balance the load determined by the control current value applied to the proportional solenoid 401, and the hydraulic pressure output from the flow path 14 is adjusted to the pressure corresponding to the control current value. In addition to the control current S ₃ that is applied to the proportional solenoid 301 of the pressure control valve 30, the controller 50 also provides a drive control signal S ₅ for the step motor 62 that rotationally positions the rotary spool 71 of the rotary valve 60.
A control signal S ₁ for the directional switching valve 7, a control signal S ₂ for the directional switching valve 8, and a control signal S ₄ for the cutback solenoid 4 are output. Additionally, a vehicle speed sensor 51 is connected to the controller 50.
vehicle speed V detected by the shift range S detected by the shift switch 52, throttle valve opening T H detected by the throttle valve opening sensor 53, hydraulic oil temperature T _O detected by the oil temperature sensor ₅₄ , engine The engine rotation speed N _E detected by the rotation speed sensor 55,
In addition, parameter signals representing various driving/driving conditions such as acceleration α, steering angle θ _S , and presence/absence of braking S _B are input.
The controller 50 determines and outputs each of the output signals S ₁ to _{S 5} based on these input signals. Next, the operation of this embodiment will be explained. As shown in FIG. 2, the rotary valve 60 includes five stages of valve parts 81 to 85, and is configured to supply working hydraulic pressure in a steady state to each shift range every time the step motor 62 rotates 36 degrees. It is composed of That is, as shown in FIG.
The point where the straight line passing through the center of 8 and 79 intersects with the inner circumferential surface 70A of the valve housing is position A, and the position 36° clockwise in the figure from position A is position B, and from position A counterclockwise in the figure. If the positions rotated by 36 degrees are sequentially C, D, and E positions, the state shown in FIG. 3, that is, the opening of the input port 61a is A.
The state of being in this position is the N/P position. When the input port 61a is in the B position, the reverse range is "R", when it is in the C position, the first speed range is "D ₁ " or the first speed fixed range is "1", and when it is in the D position, the second speed range is "R". D ₂ ”, 3rd gear range “D ₃ ” when in E position
Alternatively, the auxiliary transmission mechanism is controlled to correspond to the fourth speed range "D ₄ ". Table 1 shows each of the above selection ranges, the rotation angle position (position) of the rotary spool 81, the ON/OFF state of the directional control valves 7 and 8, and each friction element C ₁ to C ₄ ,
The relationship between the engagement/release status of B ₁ and B ₂ (engagement is indicated by "○" and release is indicated by "x") is shown.

[Table] Each of the above positions is a position in a steady state in each shift range (a state in which the gear shift operation is completely completed and the corresponding friction element is fully engaged).
Once at intermediate positions W to Z (hereinafter referred to as "transient positions") between the above positions A to E (hereinafter referred to as "steady positions"),
Control for positioning the rotating spool 71 is performed by the controller 50. For example, the operation of this embodiment during the above transition will be explained by taking as an example a case where a shift operation is performed from the neutral range "N" state to the first speed range "D ₁ ". In this case, the rotating spool 71 is rotated by 18 degrees clockwise in FIG. 3 from the A position, and the rotational angular position is set to the X position (the port 61a is at the X position). As a result, the output port 61b leading to the rear clutch _C1 is connected to the vane 123,
126, and the hydraulic pressure of the rear clutch _C1 is maintained at the previous state, that is, the drain pressure. In this state, the controller 50 determines the most suitable engagement start oil pressure P _s at that time based on input signals related to various driving/travel conditions, and controls the pressure control valve 30 to form this engagement start oil pressure P _s . Outputs control signal _S3 to As a result, the output oil pressure P ₁ of the pressure control valve 30 is
As shown in Figure 10, the hydraulic pressure for completely engaging the friction elements (hereinafter referred to as "complete engagement hydraulic pressure")
The engagement starting oil pressure decreases from P _t to the above-mentioned fastening start oil pressure P _s . Here, the "shift signal" shown in FIG. 10 refers to the shift range determined by the controller 50, from n speed (neutral range in this case) to n+1 speed (in this case first range). This indicates that the mode has changed to the high speed range). Also, "rotation angle"
is the rotation angle of the rotary spool 71, and “control current” indicates the control current given to the proportional solenoid 301. When the output oil pressure P ₁ of the pressure control valve 30 stabilizes at the engagement start oil pressure P _s , at this timing,
The controller 50 further controls the rotation spool 71.
Rotate it 18 degrees and set the rotation angle position to C position. As a result, vanes 123, 126
The output port 61b that was blocked by the fourth
You will be facing spaces 143 and 147 shown in the figure,
Input port 6 via hydraulic supply lines 160 and 161
The output oil pressure P ₁ from the pressure control valve 30 flowing into the rear clutch C 1 is supplied to the rear clutch C ₁ . From this point on, the controller 50 gradually increases the control current applied to the pressure control valve 30. As a result, the output oil pressure P ₁ of the pressure control valve 30 is
The output oil pressure P 1 gradually increases from the engagement start oil pressure P _s , and when the control current S ₃ reaches the maximum value, the output oil pressure P ₁ becomes
Reach full engagement hydraulic pressure P _t . Due to this operation, the friction elements that are engaged during the transient state during gear changes are
It is possible to supply the engagement hydraulic pressure with changing characteristics suitable for the driving condition, and it is possible to effectively reduce the shift shock caused by the friction element being engaged abruptly. Note that during other gear shifts, such as the above-mentioned shift from the neutral range to the first speed range, the rotary spool 71 is temporarily stopped at any of the transient positions W to Z, and the engagement starting hydraulic pressure is adjusted in the same way. _Ps
After these settings are made, the rotating spool 71 is set to the corresponding steady position, and the output oil pressure P ₁ of the pressure control valve 30 is gradually increased to gradually bring the friction element to a fully engaged state. . Further, for the friction element that is switched from the fully engaged state to the released state, while the rotating spool 71 is in the transient position, the engagement hydraulic pressure is maintained without being drained, and the rotating spool 71 is set to the steady position. At times, the oil passage leading to the friction element communicates with the drain passages 78 and 79 formed in the rotary spool 71, and the engagement oil pressure is removed (the change in the engagement oil pressure at this time is shown by the broken line in Fig. 10).
(shown as P ₂ ). As is clear from FIG. 4, the output port 61b leading to the rear clutch _C1 , which is a friction element that should be kept engaged from the second gear range to the fourth gear range, is connected to the output port 61b when the rotating spool 71 is in When the rotary spool 71 is set to the steady position D or E, it is switched to the line pressure supply path, so that it is closed by the vane 125 while the rotary spool 71 is in the steady position D or E. During this time, the working oil pressure of the rear clutch _C1 is maintained at the fully engaged oil pressure. Therefore, it is important for automatic transmissions because it not only allows the newly engaged friction element to be engaged while reducing the shift shock, but also prevents unnecessary opening and re-engagement of the friction element that should remain engaged. This allows the gear shift shock reduction mechanism to be maximized. Note that the rotary valve 6 shown in the above embodiment
The number of zero stages, the shape of the valve portion, and the number of stop positions may be changed depending on the number of friction elements to be controlled and the shift pattern of the auxiliary transmission mechanism. Furthermore, the same effect can be obtained by replacing the rotary valve with an oil passage switching valve that includes a plurality of spool valves and operates in the same manner as the rotary valve. (Effects of the Invention) As explained in detail above, the present invention allows the pressure control valve and the output hydraulic pressure control means to change the engagement from an appropriate engagement starting hydraulic pressure to a complete engagement in response to the friction element engaged during gear shifting. At the same time, the hydraulic switching valve and the switching valve control means cause a hydraulic pressure change from the engagement starting hydraulic pressure outputted from the pressure control valve to the complete hydraulic pressure for the friction element that is engaged during gear shifting. By supplying the output hydraulic pressure up to the hydraulic pressure that leads to engagement, when changing gears, a hydraulic pressure that changes from the appropriate engagement starting hydraulic pressure to the hydraulic pressure that leads to complete engagement can be supplied to the friction element where engagement is performed. Accordingly, it is possible to appropriately control the engagement operation of the friction element in accordance with state changes such as driving conditions and changes in oil temperature, and in particular, it is possible to obtain the effect of reducing shift shock. In addition, for friction elements that remain engaged during gear shifting, the connected oil path is switched to a line pressure supply path to maintain engagement, so the newly engaged friction element can be engaged while reducing shift shock. In addition, since unnecessary opening and re-engagement of friction elements that should be kept engaged can be prevented, the shift shock reduction function, which is important for automatic transmissions, can be maximized.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of the rotary valve in FIG. 1, FIGS. 3 to 7 are cross-sectional views of FIG.
The figure is a cross-sectional view showing an example of a specific structure of the pressure control valve in FIG. 1, FIG. 9 is a cross-sectional view showing another structural example of the same pressure control valve, and FIG. FIG. 6 is a diagram showing changes in control current, oil pressure, etc. for explaining the operation of an example. 1... Torque converter, 2... Oil pump, C ₁ ... Rear clutch, C ₂ ... Front clutch, C ₃ ... Direct clutch, C ₄ ... Low reverse brake, 7, 8... Directional switching valve,
B ₁ ...OD brake, B ₂ ...Second brake,
30, 40...Pressure control valve, 50...Controller (output hydraulic pressure control means, switching valve control means), 60
...Rotary valve (oil line switching valve), 62...
Step motor, 71...Rotating spool, 75...
... Line pressure supply path, 77 ... Fastening hydraulic pressure supply path, 7
8, 79... Drain path, 160, 161... Hydraulic supply path.

Claims (1)

[Scope of Claims] 1. In an auxiliary transmission mechanism control device for an automatic transmission that controls engagement and release of a transmission friction element constituting an auxiliary transmission mechanism of an automatic transmission, the pressure control valve is capable of freely changing the output hydraulic pressure. and an output hydraulic pressure control means that uses the pressure control valve to generate a hydraulic pressure change from an appropriate engagement starting hydraulic pressure to a complete engagement hydraulic pressure corresponding to one of the friction elements that is engaged during a shift. The inside has a supply path for output hydraulic pressure from the pressure control valve, a supply path for line pressure, and a drain path, and the oil is connected to the oil path communicating with the friction element. An oil passage switching valve that switches the passage, and an oil passage that communicates with one of the friction elements that is engaged during a gear shift, are provided with a supply passage for the output hydraulic pressure from the pressure control valve from the start of engagement until complete engagement. When the line pressure supply path is connected and the connection is maintained during the next gear change, the line pressure supply path is connected to maintain the connection, and when the connection is released, the drain path is connected. What is claimed is: 1. An auxiliary transmission mechanism control device for an automatic transmission, comprising a switching valve control means for controlling an automatic transmission. 2. The oil passage switching valve is connected to an output oil passage for a plurality of friction elements among the friction elements, a supply passage for the line pressure, a drain passage, and a supply passage for output hydraulic pressure from the pressure control valve, and is connected to the output oil passage for a plurality of friction elements among the friction elements. The switching valve control means is a rotary valve that switches the oil passage by switching the rotational angular position, and the switching valve control means performs switching control of the rotational angular position of the rotary spool, and the switching valve control means includes: When supplying the output hydraulic pressure from the pressure control valve to the friction element that is engaged during gear shifting, communication between the output oil passage leading to the friction element that is engaged and the supply passage for the output oil pressure from the pressure control valve. 2. The auxiliary transmission mechanism control device for an automatic transmission according to claim 1, wherein the timing is delayed until the output oil pressure reaches the engagement start oil pressure.