JP2001241542A - Transmission control device for auxiliary transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission controller equipped with an auxiliary transmission unit which can be realized in a prompt gear shifting to hasten the shift commencing timing of the auxiliary transmission unit so as to prevent a speed drop of a revolution of a main shaft side (opposed synchronized side) reducing an imposed load of a synchronizing mechanism at the shifting time in a gear shifting involving the switching action to the auxiliary transmission unit. SOLUTION: In a shift down process involved in the gear shifting of the auxiliary transmission unit, the auxiliary transmission unit connects a clutch (at the step S44) if the next stage of the gear shifting is not completed within the predetermined time and disconnects the clutch (at the step S48) when the gear shift to the next stage is completed (at the step S46). The shift controller can hasten the timing of the completion of the gear shifting of the transmission by completing the gear shifting in advance before releasing the clutch connection and reduce a load of the synchronized mechanism to raise the revolution of the opposed synchronized side of the auxiliary transmission using the engine revolution by the clutch connection in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an auxiliary transmission which is provided in a transmission and performs an auxiliary shift.

[0002]

[Related Background Art] In recent years, automatic transmissions have been applied not only to passenger cars but also to buses and trucks. In this type of large-sized vehicle, an automatic transmission having a torque converter has been replaced by a transmission torque capacity or the like. For example, actual Kaihei 4
As disclosed in JP-A-98623, an automatic transmission in which a gear shift operation and a clutch operation are performed by an actuator is mounted based on a manual transmission.

[0003] Such an automatic transmission has a relatively large number of gear stages in order to ensure the running performance of a large vehicle having a heavy vehicle weight. A range section is provided in series as a sub-transmission for power transmission, and the output of the main transmission section is shifted between high and low by this range section, thereby doubling the actual speed. In the shift control device described in the above-mentioned publication, when it is necessary to switch the range portion in order to achieve the next stage during downshifting, first, the clutch stroke is controlled to the disengagement side up to 65% and the main shift is performed. The gear was disengaged, and then the clutch stroke was controlled to 15% to the connected side and then 65% again.
After that, the range section is switched from high to low, and the main transmission section is put into the next stage.

By temporarily controlling the clutch to the connection side in this way, even if the rotation of the main shaft after the gear is disengaged greatly drops due to the rotation resistance of the transmission oil, for example, when the oil temperature is low, such a situation can be solved. The depression is prevented by using the rotation of the engine. Therefore, at the time of gear shifting in the subsequent range section, synchronization is performed when the rotation of the main shaft side (the synchronized side of the range section) is raised to the higher-speed output shaft side (the synchronized side of the range section) corresponding to the next stage. The load on the mechanism is reduced.

[0005]

However, in the shift control device described in the above publication, the shift in the range section is started after the clutch stroke once controlled to the connected side is again controlled to the disengaged side. Therefore, there is a problem that the shift timing of the range section is delayed, and thus the completion of the entire downshift including the main transmission section is delayed.

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the load on the synchronizing mechanism by preventing the rotation speed of the main shaft from dropping at the time of shifting involving switching of the range section, and to speed up the shifting timing of the range section, and consequently the speed. SUMMARY OF THE INVENTION It is an object of the present invention to provide a shift control device for an auxiliary transmission that can realize a proper shift.

[0007]

According to the present invention, there is provided a transmission for changing the power of an engine and transmitting the power to a drive system of a vehicle, and the transmission includes a plurality of speed stages. A main transmission unit, a subtransmission unit that constitutes the transmission, is arranged in series with the main transmission unit in terms of power transmission, and has a high and low gear position, and a clutch that disconnects and connects the power between the transmission and the engine. Position detecting means for detecting a shift position of the auxiliary transmission portion, shift command means for issuing a shift command when a shift of the transmission is required, and a clutch for disconnecting and controlling the clutch based on a shift command of the shift command means When the shift command is accompanied by a shift of the sub-transmission unit, the sub-transmission unit is shifted to the next stage. Until the passage of time When it is not detected that the sub-transmission unit has shifted to the next speed, a clutch engagement signal is output to the clutch control unit to connect the clutch, and then the position of the auxiliary transmission unit is shifted to the next speed by the position detection unit. Speed change control means for outputting a clutch disengagement signal when this is detected.

Therefore, a shift accompanied by a shift of the sub-transmission unit is performed by the shift control unit based on a shift command of the shift command unit, and a shift to the next stage of the sub-transmission unit is detected by a predetermined time. If not, the clutch is connected by the clutch control means, and then when the shift to the next stage is detected by the position detection means, the connection of the clutch is released.
Then, the rotational speed of the sub-transmission portion on the synchronized side is increased by utilizing the rotation of the engine by connecting the clutch, and then the synchronization is performed by the synchronization mechanism of the sub-transmission portion, thereby reducing the load on the synchronization mechanism. In addition, since the shift of the sub-transmission portion is completed prior to the release of the clutch connection, the shift completion timing is advanced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a shift control device for an auxiliary transmission mounted on a large truck will be described below. FIG. 1 is an overall configuration diagram showing a shift control device of an auxiliary transmission according to an embodiment. As shown in this figure, a transmission 1 is coupled to a diesel engine (hereinafter simply referred to as an engine) 2 and Is transmitted to the drive wheels via a propeller shaft (not shown).

FIG. 2 is a sectional view showing details of the transmission.
As shown in this figure, an input shaft 4 and a main shaft 5 are coaxially and rotatably supported in a casing 3 of the transmission 1, and the input shaft 4 is connected to the engine 2 via a clutch 6. When the clutch 6 is connected, rotation is input from the engine 2. A first splitter gear 11 is externally fitted to the input shaft 4 via a needle bearing 11a, and a second splitter gear 12 is externally fitted to the main shaft 5 via a tapered roller bearing 12a. These first and second splitter gears 11 and 12 are meshed with third and fourth splitter gears 14 and 15 on a counter shaft 13 supported in parallel with the main shaft 5, respectively. By switching the synchronization mechanism 16 provided between the second splitter gears 11 and 12, the input shaft 4 is switched.
Is coupled to the first splitter gear 11, rotation is transmitted to the countershaft 13 with the gear ratio of the first and third splitter gears 11 and 14, and the input shaft 4 is coupled to the second splitter gear 12. Then, the rotation is transmitted to the counter shaft 13 with the gear ratio of the second and fourth splitter gears 12 and 15. Therefore, the splitter unit M1 configured as described above
Thus, a two-stage high-low speed shift is performed.

On the main shaft 5 and the counter shaft 13, a plurality of sets of transmission gears 17,
18 (including reverse), and the main shaft 5
Each transmission gear 17 is selectively coupled to the main shaft 5 by a synchronizing mechanism 19 attached to the side gear 17, and the rotation of the counter shaft 13 is transmitted to the main shaft 5 with the coupled set of gear ratios. The main transmission unit M2 as the main transmission unit configured as described above performs four-speed shifting for forward movement.

Further, the main shaft 5 in the casing 3
An output shaft 20 is coaxially supported behind the output shaft, and a rear end of the output shaft 20 is connected to the propeller shaft. Output shaft 2
A plurality of planetary gears 21 (only one is shown) are supported by a support shaft 21a on a flange 20a formed at the front portion of the front gear 0. These planetary gears 21 are attached to a ring gear 22 disposed on the outer peripheral side. Mesh with the main shaft 5
Is meshed with a sun gear 5a formed on the outer periphery of. A rotary ring 24 is externally fitted to the output shaft 20 via a bearing 23, and a front outer circumference of the rotary ring 24 meshes with an inner circumference of the ring gear 22, and the ring gear 22 always rotates integrally with the rotary ring 24. .

A synchronizing mechanism 25 is spline-coupled to the outer periphery of the rear part of the rotating ring 24. As shown by a solid line, when the synchronizing mechanism 25 is operated forward, the rotating ring 2 is rotated.
4 is connected to one side 3a in the casing 3 to restrict the rotation of the ring gear 22, so that the planetary gear 21 rolls on the inner periphery of the ring gear 22 with the rotation of the sun gear 5a, and the main shaft 5 Is reduced and transmitted to the output shaft 20. When the synchronizing mechanism 25 is actuated rearward, the rotating ring 24 is coupled to the restricting ring 26 which is spline-coupled to the output shaft 20 as shown by the one-dot chain line. Is regulated, the rotation of the main shaft 5 is transmitted to the output shaft 20 at a constant speed. Accordingly, two-stage high and low speed shifting is performed by the range portion M3 as the sub-transmission portion configured as described above.

In this embodiment, the four forward speeds achieved by the main transmission portion M2 are combined with the two high and low speeds of the splitter portion M1 so that the speed is subdivided into a total of eight speeds. Further, by combining the total of eight gears with the two high and low gears of the range section M3, another eight gears are provided on the lower speed side of the original eight gears. As a result, a total of 16 gears are achieved.

Accordingly, for example, in the case of an adjacent shift such as switching between the first and second speeds, the main transmission portion M2 is shifted with the shift of the splitter portion M1, and the switching between the first and third speeds is performed. As described above, at the time of shifting one step, the main shifting unit M2 is shifted independently without the shifting of the splitter unit M1. Further, when shifting between the low-speed side and the high-speed side, such as between the eighth gear and the ninth gear, or between the eighth gear and the tenth gear, any one of the above-mentioned operations (including a shift involving switching of the splitter unit M1) is performed. In addition to the above, the shift of the range section M3 is executed in addition to the above-mentioned shift.

On the other hand, as shown in FIG. 1, the transmission 1 is provided with a gear shift unit 31, and the gear shift unit 31 is connected to an air tank 32. Although not shown, the gear shift unit 31 selectively operates each synchronizing mechanism 19 of the main transmission portion M2 with compressed air from the air tank 32 in accordance with switching of a large number of built-in switching valves, and shifts its gear position. Switch. The air tank 32 is connected to a splitter cylinder 34 via a pair of switching valves 33, and the splitter cylinder 34 is connected to the synchronizing mechanism 16 of the splitter unit M1 via a shift fork 34a in accordance with the switching of the switching valve 33 (see FIG. 2) to change the gear position. Similarly, the air tank 32 is connected to a range cylinder 36 via a pair of switching valves 35, and the range cylinder 36 controls the synchronizing mechanism 25 of the range section M3 via a shift fork 36a in accordance with switching of the switching valve 35. Activate to switch the gear.
Further, the air tank 32 is connected to a clutch booster 38 via a switching valve 37, and the clutch booster 38 operates to connect and disconnect the clutch 6 according to the switching of the switching valve 37.

On the other hand, an engine control unit (hereinafter referred to as an engine EC) as engine control means is provided in the vehicle interior.
An accelerator sensor 42 for detecting an accelerator operation amount by a driver, an engine speed sensor 43 for detecting an engine speed Ne, and a vehicle speed sensor 44 for detecting a vehicle speed are provided on the input side of the engine ECU 41.
The electronic governor 45 provided in the engine 2 is connected to the output side. The engine ECU 41 controls the electronic governor 4 based on a detection signal input from each sensor.
The engine 2 is operated by controlling the fuel injection amount by the control unit 5 and the injection timing by a timer (not shown).

The engine ECU 41 includes a transmission control unit (hereinafter referred to as a transmission ECU) 46 as a shift command unit, a clutch control unit, and a shift control unit.
Are connected to each other so that they can communicate with each other. On the input side of the transmission ECU 46, the gear shift unit 31, a splitter sensor 47 for detecting a shift position of the splitter unit M1, and a position detecting unit for detecting a shift position of the range unit M3. Range sensor 48, the clutch rotational speed sensor 4 for detecting the rotational speed (hereinafter referred to as clutch rotational speed) Nc of the clutch disk rotating with the input shaft 4.
9. A clutch stroke sensor 50 for detecting an operation stroke of the clutch booster 38 and a change lever unit 51 operated by a driver are connected. The output side of the transmission ECU 46 is connected to the gear shift unit 31, the switching valve 33 of the splitter section M1, the switching valve 35 of the range section M3, and the switching valve 37 of the clutch 6.

The change lever unit 51 is configured to be capable of instructing switching of a mode such as a D range or an M range, and of selecting a shift speed in the M range.
Reference numeral 46 performs a shift operation of the transmission 1 and a connection / disconnection operation of the clutch 6 according to the switching state of the change lever unit 51. That is, when the change lever unit 51 is switched to the D range, the automatic shift is performed, and the target shift speed is determined from the vehicle speed and the accelerator operation amount according to the map,
Further, when the change lever unit 51 is switched to the M range, manual gear shifting is performed, and the gear position instructed by the driver through the change lever unit 61 is regarded as the target gear position. Then, based on the information from the gear shift unit 31, the splitter sensor 47, and the range sensor 48, the changeover valves 33, 35, 37 execute the shift operation of the splitter unit M1, the main transmission unit M2, and the range unit M3, and In parallel with the clutch stroke sensor 5
The connection / disconnection operation of the clutch 6 is executed based on the information from 0 to achieve the target shift speed described above.

The transmission ECU 46 of the present embodiment
Is the same for both the D range and M range modes
When it takes longer than a predetermined time to execute the downshift of the range section M3, a so-called double clutch is executed to reduce the load on the synchronization mechanism 25 of the range section M3. As described above, when shifting the range section M3, the splitter section M1 is switched at the same time (for example, between the 8th gear and the 10th gear) and the splitter section M1 is not switched (for example, 8th gear).
However, the details of the shift control at this time will be described by taking as an example a case where the switching of the splitter unit M1 is not performed.

FIGS. 3 and 4 are flowcharts showing a shift control routine executed by the transmission ECU. First, in step S2, the transmission ECU 46 determines whether or not the shift is downshifted from the relationship between the current gear position and the next stage (target shift speed). In step S4, the transmission ECU 46 determines whether or not the shift is accompanied by switching of the range section M3. Is determined. If a negative (NO) determination is made in step S2 of step S2 or step S4, the clutch 6 is disconnected in step S6, and step S6 is performed.
At step S8, a command is output to the engine ECU 41 to adjust the engine speed Ne to a value corresponding to the next stage.
At 0, it is determined whether or not a predetermined time Ta has elapsed since the clutch was disconnected. When the predetermined time Ta has elapsed and the determination becomes YES (affirmative), the gear shift of the main transmission portion M2 is executed in step S12, and the gear shift unit 31 is executed in step S14.
It is determined based on the information from whether the gear removal has been completed.

When the determination in step S14 becomes YES due to the completion of gear removal, the main transmission unit M2 is shifted to the next gear in step S16, and it is determined in step S18 whether the gear shifting is completed. If the determination is YES due to the completion of the gear shifting, in step S20, an instruction of the engine speed Ne corresponding to the next stage is output as in step S8,
In the following step S22, it is determined whether or not the difference between the engine rotation speed Ne detected by the engine rotation speed sensor 43 and the clutch rotation speed Nc detected by the clutch rotation speed sensor 49 is equal to or less than a predetermined value. If YES, the clutch 6 is engaged in step S24, and the routine ends.

On the other hand, steps S2 and S4
Are both YES, that is, when downshifting involves switching the range section M3, as in steps S6 to S14, in steps S26 to S34, clutch disengagement, an instruction of the engine speed Ne,
The gear shift of the main transmission unit M2 is executed. Subsequent step S3
In step S6, a drive signal is output to the switching valve 35 to switch the range section M3 from high to low. If the next stage requires selection of the main transmission section M2 in step S38, a select operation is executed. Further, in step S40, it is determined whether or not a predetermined time Tb has elapsed since the signal output to the switching valve 35 in step S36, and in step S42, the shift of the range section M3 is performed based on information from the range sensor 48. It is determined whether the process has been completed. If the shifting of the range section M3 is completed before the predetermined time Tb has elapsed, the process proceeds to step S42.
Then, the process proceeds to step S16 to execute the gear shifting of the main transmission portion M2, and the clutch 6 is engaged in step S24 through steps S18 to S22.

If the predetermined time Tb has elapsed before the shifting of the range section M3 is completed, the process proceeds from step S40 to step S44, and a drive signal is output to the switching valve 37 to connect the clutch 6. Next, step S46
To determine whether or not the shifting of the range section M3 has been completed.
If the determination in S is made, a drive signal is output to the switching valve 37 to disconnect the clutch 6 in step S48, and a step S50 is executed.
It is determined whether or not the clutch 6 has been disconnected. If the determination is YES due to clutch disengagement, the process proceeds from step S48 to step S16 to execute the gear shifting of the main transmission portion M2, and the clutch 6 is engaged in step S24 through steps S18 to S22.

As described above, the shift of the range section M3 is delayed, and the reason for shifting from step S42 to step S44 is, for example, due to the rotational resistance of the transmission oil such as when the oil temperature is low, the main shaft 5 side (synchronized side). ) Greatly decreases, and the rotation is synchronized with the synchronization mechanism 2 of the range section M3.
Due to 5, there is a situation where it is difficult to pull up to the rotation on the output shaft 20 side (synchronous side) corresponding to the next stage.

As described above, in the transmission control apparatus of the present embodiment, the clutch 6 is connected at step S44 at this time, so that the rotation of the engine 2 is transmitted via the counter shaft 13 to the second splitter gear on the main shaft 5. 12 and each transmission gear 17. Main transmission unit M2 at this time
Because the gears have been removed, the main shaft 5
The rotation of the second splitter gear 12 is transmitted little by little to the main shaft 5 side via the tapered roller bearing 12a having a relatively large rotational resistance, so that a so-called rotation phenomenon occurs. As a result, the rotation speed of the main shaft 5 side gradually increases, and synchronization by the synchronization mechanism 25 is performed soon. Therefore, the load on the synchronization mechanism 25 when synchronizing the main shaft 5 side with the output shaft 20 side can be significantly reduced,
Accordingly, it is possible to prevent a synchronization delay or synchronization failure from occurring.

Further, since the shifting of the range section M3 is completed prior to the disconnection of the clutch 6 (step S48) as described above (step S46), for example, the shifting described in Japanese Utility Model Laid-Open Publication No. 4-98623. Compared with the case where the shift of the range section is started after the clutch is disengaged as in the case of the control device, the shift completion timing of the range section M3 is advanced, and thus the entire downshift including the main transmission section M2 is completed earlier. As a result, a quick downshift can be realized.

Further, after the main transmission portion M2 is de-geared as described above, the rotation is transmitted to the main shaft 5 by utilizing the corotating phenomenon of the tapered roller bearing 12a. Therefore, in this state, the main shaft 5 side is not mechanically connected to the counter shaft 13 side, so that the shift of the range section M3 can be arbitrarily performed, and as a result, the main shaft 5 is connected by the clutch connection as described above. It is possible to continue trying the shifting of the range section M3 in parallel with this while gradually increasing the rotation of. As a result, the shift of the range section M3 is completed immediately when the synchronization mechanism 25 can be synchronized with the rotation increase of the main shaft 5 side, for example, as in the shift control device described in Japanese Utility Model Laid-Open No. 4-98623. In addition, the time required for downshifting can be further shortened as compared with the case where the rotation increase of the main shaft due to the clutch connection and the shifting of the range portion are executed before and after.

Further, as described above, the shift state of the range section M3 is determined in steps S40 and S42, and only when the shift is delayed, the clutch 6 is operated in the processing after step S44 to synchronize the synchronizing mechanism 25. I'm trying. Accordingly, when the gear shift of the range section M3 is normally performed, the subsequent processing from step S16 is executed without performing the clutch operation.
Compared to the case where the clutch operation is executed unconditionally as in the shift control device described in Japanese Patent Application Publication No. 3-3, delay of downshift due to unnecessary clutch operation can be avoided.

Although the embodiment has been described above, aspects of the present invention are not limited to this embodiment. For example, in the above-described embodiment, the transmission control device for the transmission 1 mounted on the large truck is embodied. However, the type of the vehicle is not limited as long as the transmission control device includes the transmission including the sub-transmission.
For example, the present invention may be embodied in a shift control device for a transmission mounted on a passenger car.

Although the transmission 1 of the above embodiment has a splitter section M1 as a transmission mechanism in addition to the main transmission section M2 and the range section M3, the splitter section M1 does not necessarily need to be provided. The present invention may be embodied in a transmission including only the M2 and the range section M3.

[0032]

As described above, according to the shift control device for an auxiliary transmission according to the present invention, the shift to the next stage of the auxiliary transmission is performed even after a lapse of a predetermined time during the shift accompanying the shift of the auxiliary transmission. When the gear shift is not performed, the clutch is engaged to increase the rotational speed of the sub-transmission unit on the synchronized side to shift gears, thereby reducing the load on the synchronization mechanism and preventing synchronization delay and loss of synchronization. Since the shift of the sub-transmission portion is completed prior to the release of the clutch connection, the timing of the completion of the shift of the sub-transmission can be advanced, and a quick shift can be realized.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram illustrating a shift control device of an auxiliary transmission according to an embodiment.

FIG. 2 is a sectional view showing details of a transmission.

FIG. 3 is a flowchart illustrating a shift control routine executed by a transmission ECU.

FIG. 4 is a flowchart illustrating a shift control routine executed by a transmission ECU.

[Explanation of symbols]

Reference Signs List 1 transmission 2 engine 6 clutch 46 transmission ECU (shift command means, clutch control means, shift control means) 48 range sensor (position detection means) M2 main transmission section (main transmission section) M3 range section (sub transmission section) ) Tb predetermined time

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tsuyoshi Nakamura 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Keisuke Yasui 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Within the Automotive Industry Co., Ltd. (72) Inventor Tsuyoshi Asano 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation F-term (reference) 3J052 AA01 AA02 AA04 CA04 CA14 FB31 GC71 HA02 HA17 KA04 LA01

Claims (1)

[Claims] A transmission that changes the power of an engine and transmits the power to a drive system of a vehicle; a main transmission unit that constitutes the transmission, and has a plurality of shift speeds; A sub-transmission portion, which is arranged in series with the main transmission portion in terms of power transmission and has a high / low gear, a clutch for connecting and disconnecting power between the transmission and the engine, and a shift position of the sub-transmission portion Position detection means for detecting a shift, a shift command means for issuing a shift command when the transmission needs shifting, a clutch control means for controlling connection and disconnection of the clutch based on a shift command of the shift command means, The speed change of the transmission is performed based on the speed change command of the command means, and when the speed change command involves the speed change of the auxiliary transmission portion, the speed of the auxiliary transmission portion is shifted to the next stage, and a predetermined time has elapsed from the speed change command. Until the passage above When the position detection unit does not detect that the sub-transmission unit has shifted to the next stage, a clutch engagement signal is output to the clutch control unit in order to connect the clutch, and then the sub-transmission unit is detected by the position detection unit. A shift control unit for outputting a clutch disengagement signal when it is detected that a shift has been made to the next stage.