JPS6217457A - Control device for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent the generation of a speed-change shock caused by an unnecessary speed changing operation by maintaining a changed-speed stage as it is according to a signal from a changed-speed maintaining switch. CONSTITUTION:When a changed-speed maintaining switch M is thrown in, a changed-speed maintaining means N is operated by receiving a signal from the changed-speed stage maintaining switch M, to maintain the changed-speed stage as it is. This construction prevents the generation of an uncomfortable speed-change shock caused by an unnecessary speed changing operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic transmission, particularly to a control device for an electronically controlled automatic transmission.

(Prior art) In automatic transmissions, various sensors detect the driving state of the vehicle (e.g., throttle opening, accelerator pedal depression, engine speed, torque converter turbine speed, vehicle speed, brake pressure, etc.). The gear position is automatically set depending on whether the vehicle is activated or not.

However, in such automatic transmissions, the gears are automatically set according to the driving condition of the vehicle as described above, so in some cases unnecessary gear shifting operations may be performed against the driver's will. is repeated, and there is a fear that this may cause an unpleasant shift shock.

In other words, for example, when driving at high speed, if the driver inadvertently depresses or releases the accelerator pedal without any intention of changing gears, the driver may When the driver repeatedly shifts gears against the driver's will, such as between 3rd and 4th gear, and when driving on a mountain road in a lower gear, the driver may If the driver repeatedly presses and releases the accelerator pedal, the driver may automatically shift to a lower gear, for example between 2nd and 3rd gear, even if the driver wishes to continue driving in the current gear. This is done repeatedly and causes uncomfortable gear shifting for the driver and passengers.

In order to prevent such unnecessary gear shifting operations, two control modes are provided: an automatic gear shifting control mode in which automatic gear shifting is performed and a manual gear shifting mode in which manual gear shifting is performed, and these are controlled by a changeover switch. Control devices for automatic transmissions have been known for a long time (for example, Japanese Patent Laid-Open No. 5
8-184345), in this case, it is necessary to provide two control modes, an automatic shift control mode and a manual shift control mode. The configuration or its control system is complicated, which is not desirable.

(Objective of the Invention) The present invention is intended to solve the problems pointed out in the above-mentioned section of the prior art.It is an object of the present invention to prevent the occurrence of shift shock caused by unnecessary shift operations with a simple configuration, thereby improving drivability. It is an object of the present invention to provide a control device for an automatic transmission which is designed to improve the performance of the automatic transmission.

(Means for Achieving the Object) As a means for achieving the above object, the present invention provides a speed change gear mechanism, an electromagnetic means for changing the speed by switching the power transmission path of the speed change gear mechanism, and detecting the operating state. an electronically controlled automatic transmission comprising: a gear holding switch operated by a driver; A gear position holding means is provided which operates so that when a control signal from a gear holding switch is input, the control means controls the electromagnetic means to maintain the gear position at the gear position at the time when the control signal is input. be.

(Function) In the present invention, by the above means, when the driver wishes to maintain driving in the current gear, by turning on the gear holding switch at that point, the gear holding switch is released. Until then, regardless of changes in the running condition of the vehicle, the vehicle will continue to drive in the gear at which the gear shift holding switch was turned on, thereby preventing unpleasant shift shocks caused by unnecessary gear shifting operations. This will be prevented.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 shows a power transmission section and its hydraulic control circuit of an electronically controlled automatic transmission according to an embodiment of the present invention, and FIG. 2 shows a control system of the hydraulic control circuit.

(Configuration of automatic transmission) The automatic transmission includes a torque converter 1, a multi-stage gear transmission 2, an overdrive planetary gear transmission mechanism 3 disposed between the torque converter 1 and the multi-stage gear transmission 2. have.

The torque converter 1 includes a pump 5 coupled to an engine output shaft 4, a turbine 6 disposed opposite the pump 5, and a stator 13 disposed between the pump 5 and the turbine 6. Furthermore, a converter output shaft 8 is coupled to the turbine 6 . Further, a lock-up clutch 9 is provided between the converter output shaft 8 and the pump 5. This lock-up clutch 9 is always urged in the engagement direction by hydraulic oil pressure circulating within the torque converter 1, and is released and held by supplying release pressure oil from the outside into its pressure chamber 9a. be done.

The multi-stage gear transmission 2 has a front planetary gear mechanism 1O and a rear planetary gear mechanism 11, and a sun gear 12 of the front planetary gear mechanism 1O and a sun gear 13 of the rear planetary gear mechanism 11 are connected by a connecting shaft 14. . The input shaft 15 of the multi-stage gear transmission 2 is connected to the shaft via the front clutch 16! 4, and the front planetary gear mechanism 10 via the rear clutch 17.
are connected to internal gears 18, respectively. A second brake 19 is provided between the connecting shaft 14, that is, the sun gear 12.13, and the transmission case. Planetary carrier 2 of front planetary gear mechanism IO
0 and an internal gear 21 of the rear planetary gear mechanism 11 are connected to an output shaft 22. Furthermore, a low reverse brake 24 and a one-way clutch 2 are provided between the planetary carrier 23 of the rear planetary gear mechanism 11 and the transmission case.
5 is provided.

This multi-gear transmission 2 has a conventionally known transmission mechanism, and has three forward speeds and one reverse speed, and includes a front clutch 16, a rear clutch 17, and a second brake 1.
9 and a low reverse brake 24, which will be described later, are appropriately actuated by hydraulic actuators to obtain a desired gear position.

The overdrive planetary gear transmission mechanism 3 includes a planetary carrier 27 that rotatably supports the planetary gear 26.
and a sun gear 28 coupled to an internal gear 30 via a direct clutch 29. An overdrive brake 31 is provided between the sun gear 28 and the transmission case, and the internal gear 30 is connected to the input shaft 15 of the multi-gear transmission 2.

This overdrive planetary gear transmission mechanism 3 is operated by the overdrive brake 31 when the direct clutch 29 is engaged.
When released, converter output shaft 8 and input shaft 15 are directly connected, and then, when overdrive brake 31 is engaged and direct clutch 29 is released, these converter output shaft 8 and input shaft are connected. 15 in an overdrive manner.

This transmission manually selects and operates a manual valve 61 of a hydraulic control circuit (to be described later), and each shift solenoid valve is appropriately set to 0N by a control system (to be described later).
By turning off the multi-gear transmission 2,
Each friction element (clutch and brake) of the overdrive planetary gear transmission mechanism 3 operates appropriately to obtain the required gear, and the control pattern of each friction element is the same as that of the conventional structure. Settings are made for each range as shown in Table 1.

(Hydraulic control circuit) (Configuration) The hydraulic control circuit operates each friction element in the operation pattern shown in Table 1 above in response to the driver's selection operation so that a predetermined gear can be obtained. It has a circuit configuration, which will be explained in detail below.

In the hydraulic control circuit, reference numeral 50 denotes a hydraulic pump,
The hydraulic oil discharged from the hydraulic pump 50 is regulated to a predetermined pressure by a pressure regulating valve 62 and introduced into a manual valve 61 via a pressure line 101.

The manual valve 61 has five ports that can communicate with the pressure line O1. That is, boat a communicates with the pressure line 101 in the three ranges (D, 2.1), boat b communicates with the pressure line 101 in the two ranges (D, 2), and the pressure line only in the R range. 101, and (P, R, 2,
Boats d, . . . (R.

The two ranges 1) have a boat e communicating with the pressure line 101.

Boat a is connected to line 111.

This line 111 has three pilot lines at its end, namely, the l-2 shift solenoid valve 51 that controls the operation of the -2 shift valve 63, and the throttle 86.
a first pilot line lQ2 equipped with a 2-3 shift solenoid valve 52 for controlling the operation of a 2-3 shift valve 64, and a second pilot line 1 equipped with a calibrator 87'.
03 and 3-4, which controls the operation of the shift valve 65.
3rd with 4 shift solenoid valve 53 and throttle 88
It branches into a pilot line 104. In addition, by turning ON (energizing) each of these solenoid valves 51, 52, 53, each drain line 105 is
, 106, 107 to close each pilot line 10.
2, 103, and 104, respectively.
This moves each shift valve 63, 64, 65 from the OFF position (rightward moving position) to the ON position (leftward moving position) to open and close the hydraulic circuit of the associated friction element, and its operation pattern is set according to each range and gear as shown in Table 2 below.

Table 2 In this case, the 3-4 shift solenoid valve 53 is D
At the 1st and 2nd speeds in the range, they are at the OFF position, but at the 1st and 2nd speeds at the 1 and 2 ranges, they are at the ON position, as shown in parentheses. This is l
This is to set the 3-4 shift solenoid valve 53 to the ON position in the range and 2 range, and load pilot pressure onto a backup control valve 70, which will be described later.

In addition, this gear change setting (i.e., ON-OFF control of each shift solenoid valve 51, 52, 53 and lock-up solenoid valve 54) is based on the map of controller X, i.e., engine rotation speed, turbine rotation speed, and vehicle speed. A control signal A1 is output based on a shift line preset according to a speed element detected from one of them and an engine load element detected from a throttle opening.
．． At.

This is done by A3 and A4.

In this embodiment, four solenoid valves 5 are used.
1, 52, 53, and 54 correspond to the electromagnetic means in the claims, and the controller X corresponds to the control means in the claims.

The first pilot line 102 is a first pilot line that communicates with the right end portion (pilot pressure load portion) of the 1-2 shift valve 63 on the downstream side of the 1-2 shift solenoid valve 51.
A second branch line 10 that communicates with the branch line l02a and the right end part (pilot pressure load part) of the cutback valve 66
It is branched into two lines 2b.

Line pressure is supplied to both ends of the 1-2 shift valve 63 via a line 112 branching from line III and a line 113 further branching from line l12.
A manual valve 61 is located in the middle of the shift valve 63.
Line pressure is introduced through a line 122 communicating with port e of each. Note that this line 122 is communicated with the line 123 when the l-2 shift valve 63 is in the OFF position, that is, in the shift position. Further, this line 123 is connected to a low reverse brake actuator 44. On the other hand, line +13 is connected when the l-2 shift valve 63 is in the ON position, that is, the shift position is 1.
It is communicated with the line 161 when the gear shift position is at a position other than the gear shift position.

This line 161 is connected to the engagement side 45A of the second brake actuator 45.

Also, a reducing valve 68 is connected to this line 161.
An accumulator 79 and a one-way orifice 82 are provided, the back pressure of which is controlled by.

The 2-3 shift valve 64 is set to 0N- by pilot pressure introduced from the line 103 connected to its right end.
It is controlled to be turned off. This 2-3 shift valve 64 is connected to port b of the manual valve 61.
A line 121 communicating with port C and a line 131 communicating with port C are respectively connected.

Of these lines 121 and 131, line 121
is connected to the line 132 when the 2-3 shift valve 64 is in the ON position (i.e., the 3rd or 4th gear shift position), and the line 131 is connected to the OFF position of the 2-3 shift valve 64 (i.e.,
The gears are selectively connected to the line 132 at the first or second gear position. still,
A reducing valve 67 and a one-way valve 85 are connected in parallel to the line 131.

On the downstream side, the line 132 has a line 136 connected to the front clutch actuator 41 and a release side 45 of the second brake actuator 45.
It is branched into a line 138 that connects to B. A one-way orifice 74 is installed on the upstream side of the branch part of this line 132 and acts to throttle the hydraulic fluid flowing from the 2-3 shift valve 64 toward the branch part. or,
A one-way orifice 75 that acts to throttle the hydraulic fluid in the direction from the second brake actuator 45 side to the 2-3 shift valve 64 side is installed at a position immediately downstream of the branch part of the line 138. Furthermore, the branch part of this line 132 and the one-way orifice 7
A 3-2 timing valve 72 is provided between the intermediate position of 4 and the downstream position of the one-way orifice 75 of the line 138, which is operated by pilot pressure introduced from the vacuum throttle valve 69 through the line 155. Line 140 is connected in parallel to line 137, which includes a 3-2 timing valve 73 operated by pilot pressure introduced from primary portion 47B of governor 47 via line 163. Further, a one-way orifice 83 is provided on the downstream side of the line 138 from the branching part of the lines 137 and 138.
is provided.

Further, in the line 136, there is a one-way accumulator 78 whose back pressure is controlled by line pressure supplied via a line 139 branching from the line 132, which acts to throttle the hydraulic fluid flowing out from the accumulator 78. It is connected via an orifice 81. Note that back pressure control of the accumulator 78 is performed by the reducing valve 67 described above.

The third pilot line 104 is a first branch line 104a that communicates with the right end of the 3-4 shift valve 65 on the downstream side of the 3-4 shift solenoid valve 53.
It is branched into two branch lines: a second branch line 104b that guides pilot pressure to a backup control valve 70, which will be described later.

A line 141 branching from the pressure line 101 is connected to an intermediate portion of the 3-4 shift valve 65. This line 141 connects to the line 142 at the OF2 position of the 3-4 shift valve 65 (i.e., at a shift position other than 4th gear).
be communicated with.

On the downstream side, this line 142 has a line 143 that communicates with the direct clutch actuator 42.
and a line 144 communicating with the release side 46B of the overdrive brake 46, and an oil pressure switch 90 is installed at a position upstream from the branch. Also, the line 143 has an accumulator 7.
7 is provided. In addition, overdrive brake 46
The fastening side 46A of is connected to the pressure line IO1 via a line 148.

On the other hand, a line 151 that communicates with port d of the manual valve 61 is connected to the left end of the 3-4 shift valve 65, and the spool of the 3-4 shift valve 65 is in a select position other than the D range. is the line 1
Forced OF by line pressure introduced through 51
Positioned and held in two positions. Further, the vacuum throttle valve 6 is branched from this line 151.
9, a throttle backup valve 71 and a backup control valve 70 are connected in series, and the backup control valve 70
is installed so as to be located downstream of the throttle backup valve 71. This throttle backup valve 71 causes the line pressure standing on the line 152 to act on the vacuum throttle valve 69 in the 2nd range and lunge where the engine brake is applied, and passes the line pressure to the pressure regulating valve 62 through the vacuum throttle valve 69.
This acts to increase the line pressure by driving the line in the pressure increasing direction. Further, the back-up control valve 70 is located between the throttle back-up valve 71 and the vacuum throttle valve 69, and is operated when pilot pressure is established in the branch line 104b, that is, 3-4.
When the shift solenoid valve 53 is turned on, the line 152 is opened and the throttle backup valve 7 is opened.
This functions to enable the line pressure increasing effect of No. 1.

The line 112 has a line 116 communicating with the rear clutch actuator 43 at its downstream end, and a line 117 communicating with the secondary portion 47A of the governor 47.
It is divided into two lines. This line 116 includes an accumulator 80 and a one-way orifice 84.
are provided for each. Furthermore, this line 112
The line 114 branching from the accumulator 7
9 reducing valves 68 for adjusting back pressure are provided.

Furthermore, the line 149 has a lock-up valve 76 and an aperture 9! The lock-up clutch 9 is connected to the working chamber 9a of the lock-up clutch 9 through a line 146. The pilot line 145 of this lock-up valve 76 includes a throttle 89 and a lock-up solenoid valve 5.
4, and the lock-up clutch 9 is engaged when the lock-up solenoid valve 54 is turned on, pilot pressure is established in the line 145, and the line 146 is drained by the spool. There is. In this embodiment, the lock-up clutch 9 is engaged only between the second and fourth speeds of the D range.

(Function of Hydraulic Control Circuit) As shown in FIG. 2, the automatic transmission Z uses four shift solenoid valves 51, 52, 53, 54 of the hydraulic control circuit to transmit various engine signals such as throttle opening signal and engine rotation speed signal. Control signals A , A x output from the controller X based on the state detection element.

0N- with the control pattern shown in Table 2 by A3.
By performing OFF control, each friction element operates according to the operation pattern shown in Table 1, and a predetermined gear position is obtained.

Hereinafter, the operation of the hydraulic control circuit and its effect will be briefly explained using an example when the vehicle is traveling in the D range.

When driving in D range, manual valve 61 boat a
and boat b are connected to the pressure line 101, and 3
The shift solenoid valves 51, 52, and 53 are both in the ON position. Therefore, in the 1-2 shift valve 63, line +13 and line 161 communicate with each other, and line pressure is applied to the engagement side 45A of the second brake actuator 45, and in the 2-3 shift valve 64, line 12+ and line 132 are in communication with each other, and line pressure is applied to the release side 45B of the front clutch actuator 41 and the second brake actuator 45, respectively. Therefore, the front clutch 16 is engaged and the second brake 19 is released.

On the other hand, since the line 123 is drained, the low reverse brake 24 is released. That is, the engine brake is not applied.

Also, in the 3-4 shift valve 65, line +42
and line 151 are both drained. Therefore, the direct clutch 29 is released. On the other hand, in the overdrive brake 46, line pressure is introduced only to the engagement side 46A via the pressure line 101, and the release side 46B is drained, so the overdrive brake 31 is in the engagement state.

Furthermore, line pressure is introduced into the line 112,
Therefore, the rear clutch 17 is in the engaged state. By operating each friction element in this manner, four-way travel in the D range is realized.

(Control System) As shown in FIG. 2, the control system includes a controller X that outputs control signals to the four solenoid valves 51, 52, 53, and 54 of the hydraulic control circuit. The controller X receives, as control elements, the throttle opening of the engine, the turbine rotation speed, the engine rotation speed, ON/OFF of the brake operation, vehicle speed, and the like.

The Controller Signal A+, A
t, A 3. A4 is output, respectively, and functions to set the gear stage and perform lock-up control.

Further, in the control system of this embodiment, the present invention is applied, and a gear position holding switch M, which is operated ON-OFF by the driver, is provided on the select lever Y, and a gear position holding switch M is provided on the select lever Y, and
is provided with a gear position holding means N, and the gear position holding switch M
When a signal is input to the controller .

Therefore, for example, when driving in 4-way in D range (while driving in high gear), the driver may decide that it is better to continue driving in the current gear for a while based on the road condition ahead, and switch the gear hold switch M. When the gear holding switch M is turned on, the gear holding switch M
In response to a signal from the gear position holding means N, the gear stage holding means N operates, and the operation of each of the solenoid valves 51, 52, 53, and 54 is frozen while remaining in the 4th gear state. Once the gear position holding means N is turned on,
When activated, the gear position holding action is maintained until the gear position holding switch M is operated to release the gear position. For this reason, for example,
Even if the driver repeatedly depresses and releases the accelerator pedal carelessly (that is, without any active intention to shift gears), the accelerator pedal depresses and releases the accelerator pedal.
Regardless of the release operation (i.e., acceleration/deceleration request signal), the running state at 4th gear is maintained, thereby preventing unnecessary gear changes and the occurrence of unpleasant gear change shocks.

Furthermore, when the engaged state of the gear position holding switch M is released,
In response to the release signal from the gear holding switch M, the gear holding means N is turned off, its gear holding action is released, and accordingly, the operation control of the gear changes to the same speed as before the gear holding switch M was turned on. resumes from the position.

This gear position holding control is specifically executed according to the flowchart shown in FIG. 3, and will be explained below.

After the control is started, first, various current data of the vehicle (e.g., throttle opening, turbine rotation speed, engine rotation speed, vehicle speed, etc.) that serve as shift control elements are input (step S).
1).

Next, it is determined based on each of the above data whether a shift command has actually been issued (step S).

If the result of the determination is that no gear shift command has been issued (that is, there is no need to shift gears), no special control is performed because it is sufficient to maintain the current gear position.

On the other hand, if a gear shift command is issued, then in step S3, the gear position holding switch M is turned ON-OFF.
Determine.

As a result of the determination, if the gear position holding switch M is not turned on, automatic shift control is performed by comparing each of the control elements described above with a shift line stored in advance in the controller X (step S). .

On the other hand, if the gear position holding switch M is turned on, it is necessary to maintain the current gear position, so steps S5°Se, S7. At step Ss, the current gear position is determined and a control signal is output to maintain the current gear position (steps S , , S , ,
S,,,S,ri.

When the gear position holding switch M is released after a period of time has elapsed,
Automatic gear shifting is resumed from the gear position in the holding state (step S3→step S4).

In this way, in this automatic transmission Z, the operation of the four solenoid valves (corresponding to electromagnetic means in the claims) 51, 52, 53, and 54 provided in the hydraulic control circuit is controlled to maintain the gear position. By controlling the gear stage holding means N whose operation is controlled by the signal from the switch M,
It is possible to maintain the gear position at a predetermined gear position according to the driver's will, or to cancel the holding action and perform normal automatic gear shifting. In other words, by simply adding a gear position holding switch M and a gear position holding means N to the control system, an automatic transmission having a conventional structure that only performs automatic gear shifting can be fixed to automatic gear shifting operation and a predetermined gear position. The automatic transmission can select between two operating states. For this reason, its configuration is simpler than that of conventional automatic transmissions, which have two control modes: automatic shift control mode and manual shift control mode, to realize automatic shift driving and fixed gear speed driving. This is advantageous in terms of both weight and cost.

(Effects of the Invention) The automatic transmission control device of the present invention includes a speed change gear mechanism, an electromagnetic means for changing the speed by switching the power transmission path of the speed change gear mechanism, and signals from a plurality of sensors that detect the driving state. In an electronically controlled automatic transmission equipped with a control means for automatically shifting gears by driving and controlling an electromagnetic means based on the above, a gear position holding switch operated by a driver and control from the gear position holding switch The present invention is characterized by further comprising a gear position holding means which operates so that when a signal is input, the control means controls the electromagnetic means to maintain the gear position at the gear position at the time when the control signal is input. .

Therefore, according to the automatic transmission control device of the present invention, (1) By turning on the gear position holding switch,
The gear position holding means operates in response to a signal from the gear position holding switch, and the gear position is maintained at the same gear position when the gear position holding switch was turned on. This prevents the occurrence of unpleasant shift shocks and improves drivability accordingly.

Furthermore, since the gear position holding function is realized by only two components of the control system, namely the gear position holding switch and the gear position holding means, conventional automatic transmissions (for example, Japanese Patent Application Laid-open No. 184345/1983) There are two control modes for the control device: automatic shift control mode and manual shift control mode.
This also has the effect of simplifying the structure compared to the case where two control modes are set.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of an automatic transmission equipped with a control device according to an embodiment of the present invention, Fig. 2 is a control system diagram of the automatic transmission shown in Fig. 1, and Fig. 3 is a system diagram of a control system for the automatic transmission shown in Fig. 1. It is a flowchart. ■...Torque converter 2...Multi-stage gear transmission 3...Planetary gear transmission mechanism 10...Front stage planetary gear mechanism 11...Rear stage planetary gear mechanism 16...・Front clutch 17...Rear clutch 19...Second brake 24...Low reverse brake 29...Direct clutch 31...Overdrive brake 41...Front clutch actuator 42・
...Direct clutch actuator 43...Rear clutch actuator 44...
・Low reverse brake actuator 45・・Second brake actuator 46・
... Overdrive brake 47 ... Governor 51 ... l-2 shift solenoid valve. 52...2-3 shift solenoid valve 53...
・3-4 shift solenoid valve 54...Lock-up solenoid valve 61...Manual valve 62...Pressure regulating valve 63...1-2 shift valve 64...2-3 shift valve 65...3-4 shift pulp 69...vacuum throttle valve 70...
Backup control valve 71...Throttle backup valve M...Gear position holding switch N...Gear position holding means X...Controller Y...Select lever application Person M To Tsuda Co., Ltd. 7, , l

Claims (1)

[Claims] 1. A speed change gear mechanism, an electromagnetic means for changing the speed by switching the power transmission path of the speed change gear mechanism, and an automatic speed change by driving and controlling the electromagnetic means based on signals from a plurality of sensors that detect driving conditions. In an electronically controlled automatic transmission, the electronically controlled automatic transmission is equipped with a gear holding switch operated by a driver, and when a control signal from the gear holding switch is input, the control means controls the electromagnetic means. A control device for an automatic transmission, comprising: a gear position holding means that acts to maintain the gear position at the time when the control signal is input.