JP5896698B2 - Control device for automatic transmission - Google Patents

Description

  The present invention relates to a control device for an automatic transmission for a vehicle.

  In a vehicle generally called an AT vehicle equipped with an automatic transmission, that is, an automatic transmission, the engine rotation is connected to the torque converter by releasing the lock-up clutch of the torque converter for a certain period of time during shifting. In general, the transmission is not transmitted to the transmission, in other words, the lock-up state is maintained for a certain period of time.

  In such a vehicle, when shifting is performed when the accelerator pedal depression amount is set to zero or close to it when the vehicle speed increases, control is performed so as to increase the time from the non-lock-up state to the lock-up state. ing. This is because the gear ratio of the transmission is determined not only by the accelerator pedal depression amount, the throttle valve opening, or the intake air amount but also by the vehicle speed.

  That is, after changing the gear ratio by the transmission, when the lock-up state is set again, the rotational speed of the torque converter, which is the rotational speed on the input shaft side of the transmission, is affected by the vehicle speed, so the rotational speed is unlikely to decrease. ing. On the other hand, the engine speed is quickly reduced when the amount of depression of the accelerator pedal is made zero. As a result, if the lock-up state is set at the same timing as during normal gear shifting, the lock-up clutch is engaged with the turbine rotation speed greatly exceeding the engine rotation speed, and excessive impact is generated on the engine. . Therefore, in order to avoid such a situation, it is necessary to enter the non-lock-up state only for the time until the turbine speed approaches the engine speed. Such a problem is particularly noticeable when the gear ratio of the transmission is changed higher.

  If so, the non-lock-up state becomes longer at the time of shifting, and therefore the ratio of the time for setting the lock-up state during operation, that is, the lock-up region is not expanded. In other words, this hinders improvement in fuel consumption due to the expansion of the lock-up area.

  In addition, as disclosed in Patent Document 1, in such a case, a technique for avoiding an impact on the engine by increasing the intake air amount by an idle speed control valve and suppressing a decrease in engine speed is also disclosed. .

  However, the amount of adjustment of the intake air amount by the idle speed control valve is limited, and adjustment is difficult when the difference between the engine speed and the turbine speed is large. Although adjustment by special means such as the introduction of an electronic throttle valve is also conceivable, this causes an increase in the number of parts of the engine and an associated increase in cost.

JP 7-81460 A

  The present invention focuses on the above-described problems, and an object of the present invention is to provide a control device for an automatic transmission that can shorten the time required for a non-lock-up state due to a shift.

  In order to achieve such an object, the present invention takes the following measures.

That is, the control device for an automatic transmission according to the present invention includes a transmission that is connected to an engine and capable of shifting the rotation of the engine, and is interposed between the transmission and the engine so that the rotation of the engine is on the input shaft side of the transmission A control device for an automatic transmission that has a lockup state in which the direct connection is established and a torque converter capable of taking a non-lockup state in which the direct connection state is released, and in which the transmission shifts in the non-lockup state, If shifting when the opening of the depression amount or throttle valve and the accelerator pedal by the a transmission capable shifting state has decreased to below a predetermined value, the input shaft side and output shaft side within the transmission as the rotation speed of the input shaft side is independent of the rotation of the output shaft side by releasing the engagement of the shifting clutch provided between rotation of the input shaft side of the engine speed the transmission When the difference between becomes a predetermined value, the torque converter and lock-up state, characterized by engaging the input shaft side and output shaft side of the transmission thereafter.

  Here, “releasing the engagement between the input shaft side and the output shaft side of the transmission” is not only a neutral state in which all the clutches and brakes in the transmission are all released, but also any clutch or This is a concept including a mode in which the rotation on the input shaft side is not transmitted to the output shaft side as a result even if the brake is engaged.

  With such a configuration, the rotational speed on the input shaft side of the automatic transmission can be quickly reduced without depending on the rotation on the output shaft side. As a result, even in a situation where the engine speed decreases as the accelerator pedal depression amount decreases, the lockup state can be quickly established, so that the fuel consumption by effectively expanding the lockup region during the operation time can be achieved. Can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, the control apparatus of the automatic transmission which can implement | achieve the improvement of a fuel consumption by effectively expanding the lockup area | region during driving time can be provided.

1 is a schematic configuration diagram of an engine and an automatic transmission according to an embodiment of the present invention. Explanatory drawing of the principal part which concerns on the same embodiment. Action explanatory drawing which concerns on FIG. Structure explanatory drawing of the other principal part which concerns on the same embodiment. FIG. 5 is an operation explanatory diagram according to FIG. FIG. The flowchart which concerns on the same embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The automatic transmission 2 according to the present embodiment is generally called an automatic transmission, and is mounted on a normal passenger car such as an A / T car.

  The automatic transmission 2 is interposed between the transmission 4 that transmits the rotation of the engine 1 to a wheel (not shown), and the rotation of the crankshaft 100 of the engine 1 and the input shaft 400 of the transmission 4. And a torque converter 3 capable of taking a lock-up state in which the transmission can be performed and a non-lock-up state in which the transmission is not performed.

  As shown in FIGS. 2 and 3, the torque converter 3 can rotate with the cover 31 fixed to the crankshaft 100 of the engine 1, the turbine 33 that rotates together with the input shaft 400 of the transmission 4, and the turbine 33. The torque converter 3 itself has a lock-up clutch 32 that operates to switch between the lock-up state and the non-lock-up state.

  In the figure, the flow of hydraulic oil for operating the lockup clutch 32 is indicated by arrows. FIG. 2 shows a lock-up state in which the lock-up clutch 32 is pressed against the cover 31 due to a hydraulic pressure difference between the left and right by forming a flow of hydraulic oil from the left side to the right side in the drawing. In this lock-up state, the crankshaft 100, the turbine 33 and the input shaft 400 of the engine 1 are directly connected and can rotate integrally.

  On the other hand, FIG. 3 shows a non-lock-up state in which the lock-up clutch 32 and the cover 31 are separated by a hydraulic pressure difference by forming a flow of hydraulic oil from the right side to the left side in the drawing. In this unlocked state, the direct connection state between the crankshaft 100 of the engine 1 and the turbine 33 and the input shaft 400 of the transmission 4 is released.

  In this embodiment, the transmission 4 is in a state in which a vehicle having a high gear ratio can be advanced in order from the first speed, the second speed, the third speed, and the fourth speed by operating each clutch and each brake, which will be described later. The existing state that realizes a state in which the vehicle can be moved backward with a predetermined gear ratio and a neutral state in which engagement by any clutch and brake is released. In the state set by the driver to the “D range”, the transmission 4 is controlled by the electronic control unit 6 so as to be able to perform a shift according to the amount of depression of the accelerator pedal 5 or the opening degree of the throttle valve and the vehicle speed.

  The automatic transmission 2 according to this embodiment is controlled by the electronic control unit 6. The electronic control device 6 is a microcomputer system including a CPU, a RAM, a ROM, an I / O interface, and the like. The control program is stored in the ROM in advance, and when executed, it is read from the ROM into the RAM and decoded by the CPU.

  The electronic control unit 6 then detects the engine speed signal a related to the rotational speed of the crankshaft 100 detected on the engine 1 side, that is, the engine rotational speed, and the opening related to the opening of a throttle valve (not shown) detected in the engine 1. A degree signal b, an accelerator signal c related to the amount of depression of the accelerator pedal 5, and a turbine speed signal d related to the speed of the turbine 33 of the torque converter 3 are input. On the other hand, the electronic control unit 6 outputs an output signal for appropriately controlling the engine 1, as well as a lockup signal e for operating the lockup clutch 32 and a transmission 4 as shown in FIGS. 2 and 3. A shift signal f for appropriately performing the shift is output.

  Note that the electronic control unit 6 according to the present embodiment has the condition that the amount of depression of the accelerator pedal 5 is reduced from zero to substantially zero for the engine 1 and the engine speed is equal to or higher than a certain speed such as an idle speed. However, since the specific mode of the fuel cut is an existing one, a specific description is omitted.

  Therefore, the electronic control device 6 as the control device of the automatic transmission 2 according to the present embodiment is such that the transmission 4 shifts in a non-lock-up state, and the transmission 4 is in a shiftable state and the accelerator pedal 5. When shifting is performed when the amount of depression or the opening of the throttle valve drops below a predetermined value of zero or substantially zero, the engagement between the input shaft 400 side and the output shaft 415a side described later in the transmission 4 is released. When the difference between the engine rotational speed and the rotational speed on the input shaft 400 side of the transmission 4 falls within the predetermined value x, the torque converter 3 is brought into a lock-up state, and then the input shaft 400 side of the transmission 4 is And a program for engaging the output shaft 415a side.

  Here, in this embodiment, when shifting the transmission 4 from, for example, the 3rd speed to the 4th speed, “disengagement between the input shaft 400 side and the output shaft 415a side in the transmission 4” is described with reference to FIGS. This will be described with reference to FIG.

  The transmission 4 shown in the figure uses a planetary gear mechanism, and includes a reverse clutch 401, a forward clutch 402, a rear clutch 403, a one-way clutch 404, a 2 & 4 brake 405, and a 1 & reverse brake 406 corresponding to the transmission clutch. By appropriately engaging / disengaging, the rear planetary sun gear 408, planetary carrier 409, front planetary sun gear 410, planetary ring gear 413, planetary short pinion 411, planetary long pinion 412 and planetary are various gears. By appropriately meshing the ring gear 413, the primary reduction driven gear 414 is connected via the primary reduction drive gear 414 from the input shaft 400 via the intermediate shaft 407 in some cases. To the output shaft 415a which is a rotation axis of the ya 415 it is intended to transmit power.

  FIG. 4 shows components that are engaged with each other when traveling with the transmission 4 set to the third speed with light ink. In the figure, the forward clutch 402 and the rear clutch 403 are operated so that the input shaft 400, the rear planetary sun gear 408, and the planetary carrier 409 rotate in the same direction. As a result, the planetary short pinion 411 and the planetary long pinion 412 are locked, and the planetary ring gear 413 receives the rotational force in the right direction, so that the gear ratio of the input shaft 400 / output shaft 415a, that is, the gear ratio 1.0. Thus, the rotational force in the forward direction is transmitted to the output shaft 415a.

  In FIG. 5, the components that are engaged with each other when traveling with the transmission 4 set to the fourth speed are marked with light ink. In the drawing, the rotation of the input shaft 400 is directly transmitted to the intermediate shaft 407 by operating the rear clutch 403 and the 2 & 4 brake 405, and the rotational force in the right direction is transmitted to the planetary carrier 409. On the other hand, since the front planetary sun gear 410 is locked by the 2 & 4 brake 405, the planetary long pinion 412 supported by the planetary carrier 409 revolves on the front planetary sun gear 410 while rotating by receiving the rotational force in the right direction. The planetary ring gear 413 is rotated rightward. As a result, the rotational force in the forward direction is transmitted to the output shaft 415a at a gear ratio of the input shaft 400 / output shaft 415a, that is, a gear ratio of 0.696.

  Accordingly, in this embodiment, as shown in FIG. 6, only the 2 & 4 brake 405 is released from the state shown in FIG. 4, so that the rotation of the input shaft 400 is not transmitted to the output shaft 415a. The release is performed. Specifically, in the same figure, the rotation of the input shaft 400 is directly transmitted to the intermediate shaft 407 by operating the rear clutch 403 as in FIG. 5, but the rotation of the planetary long pinion 412 is the operation of the 2 & 4 brake 405. Is released, the front planetary sun gear 410 is caused to idle in the left direction and is not transmitted to the planetary ring gear 413. Thereby, transmission from the rotating shaft from the input shaft 400 is interrupted, and so-called disengagement of the shift clutch is realized.

  Of course, the disengagement of the so-called shift clutch is performed by disengaging all of the reverse clutch 401, forward clutch 402, rear clutch 403, one-way clutch 404, 2 & 4 brake 405 and 1 & reverse brake 406 corresponding to the shift clutch. It is good also as a state. Alternatively, only the 2 & 4 brake 405 may be applied. In this case, although not shown, since the operation of all of the reverse clutch 401, the forward clutch 402, and the rear clutch 403 is released, the rotation of the input shaft 400 causes the rotation of the intermediate planet 407 and the front planetary sun gear 410 to the rear planetary sun gear. Since it is not transmitted to 408, the disengagement of the shift clutch is realized.

  Next, a control mode at the time of shifting from, for example, the third speed to the fourth speed in the present embodiment will be described with reference to the flowchart of FIG.

  First, when shifting is performed (step S1), the torque converter 3 is set to a non-lock-up state (step S2). At this time, if the amount of depression of the accelerator pedal 5 has been reduced to zero or substantially zero (step S3), the shift clutch is engaged by releasing the action of the forward clutch 402 as shown in FIG. Release is performed (step S14). As a result, the turbine rotational speed, which is the rotational speed of the input shaft 400, is not affected by the rotational speed of the output shaft 415a that is affected by the vehicle speed. As a result, the turbine rotation speed decreases rapidly. Since the difference between the turbine rotational speed and the engine rotational speed immediately becomes equal to or less than the predetermined value x (step S15), the lockup clutch 32 is engaged in the torque converter 3 (step S16), and thereafter, as shown in FIG. The shift clutch is engaged to the fourth speed (S17). At this time, an impact is caused in the transmission 4 due to the engagement between the input shaft 400 whose rotational speed has decreased and the output shaft 415a rotating depending on the vehicle speed. There is no problem because the machine 4 is in a range that can be received during normal operation. Further, since this impact occurs at a position through the torque converter 3 with respect to the engine 1, there is almost no influence on the engine 1.

  On the other hand, when gear shifting is first performed (step S1), after the non-lock-up state (step S2) is set, if the depression amount of the accelerator pedal 5 is not reduced to zero or substantially zero (step S3), it is normal. If the difference between the turbine speed and the engine speed is less than or equal to the predetermined value x (step S24), the third speed shown in FIG. 4 is changed to the fourth speed shown in FIG. After performing the shift (step S25) and knowing, the torque converter 3 may be brought into a lock-up state.

  By adopting the above-described configuration, the electronic control device 6 that is the control device for the automatic transmission 2 according to the present embodiment quickly reduces the turbine rotation speed without depending on the rotation on the output shaft 415a side. Even in a situation where the engine speed decreases due to a decrease in the amount of depression of the accelerator pedal 5, the lockup state can be quickly established, so that the fuel consumption can be improved by effectively expanding the lockup region during the operation time. Improvement has been realized.

  In particular, when the amount of depression of the accelerator pedal 5 is zero or substantially zero, the engine 1 normally performs fuel cut control separately. In addition, the fuel cut control is performed until the engine speed decreases to, for example, the idle speed. The decrease in engine speed during travel occurs more slowly in the lock-up state than in the non-lock-up state.

  In other words, according to this embodiment, since the time for the non-lock-up state at the time of a shift at the time of fuel cut is effectively reduced, it is possible to secure a large amount of fuel cut travel time during operation. Yes. As a result, it contributes directly to the improvement of fuel consumption.

  Although the embodiment of the present invention has been described above, the specific configuration of each unit is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the engagement between the output shaft of the transmission and the input shaft is released from the depression amount of the accelerator pedal. Of course, the throttle valve opening degree and the intake air amount are not limited to the depression amount of the accelerator pedal. May be taken into consideration. Moreover, although the aspect using the transmission which can change to 4th speed was disclosed in the said embodiment, of course, it is not restricted to the said aspect. In the above embodiment, the mode of shifting from the 3rd speed to the 4th speed has been described. Of course, the same applies even when shifting from the 2nd speed to the 3rd speed and when shifting from the 4th speed to the 3rd speed. The effect of. Further, specific modes such as the engine and the torque converter are not limited to those of the above-described embodiment, and various modes including the existing ones can be applied.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  The present invention can be used as a control device for an automatic transmission for a vehicle.

DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Automatic transmission 3 ... Torque converter 4 ... Transmission 400 ... Input shaft 415a ... Output shaft 5 ... Accelerator pedal 6 ... Automatic transmission control device (electronic control device)
x ... predetermined value

Claims (1)

A transmission connected to the engine and capable of shifting the rotation of the engine, a lockup state interposed between the transmission and the engine and transmitting the rotation of the engine directly to the input shaft side of the transmission and the direct A torque converter capable of taking a non-lock-up state in which a simple transmission is released, and a control device for an automatic transmission in which the transmission shifts in the non-lock-up state,
If shifting when the opening of the depression amount or throttle valve and the accelerator pedal by the a transmission capable shifting state has decreased to below a predetermined value, the input shaft side and output shaft side within the transmission By disengaging the shift clutch provided therebetween, the rotation speed on the input shaft side does not depend on the rotation on the output shaft side, and the engine rotation speed and the rotation speed on the input shaft side of the transmission are An automatic transmission control device, wherein when the difference falls within a predetermined value, the torque converter is brought into a lock-up state, and thereafter the input shaft side and the output shaft side of the transmission are engaged.

Images