JP4197820B2 - Transmission control device for a transmission having a sub-transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission control device for a transmission including an auxiliary transmission.
[0002]
[Related background]
In recent years, automatic transmissions have been applied not only to passenger cars but also to buses, trucks, and the like. In this type of large vehicle, instead of an automatic transmission provided with a torque converter, for example, a utility model 3 As described in Japanese Patent Application Publication No. 29760/2000, an automatic transmission is mounted on the basis of a manual transmission, in which a gear shift operation and a clutch operation are performed by an actuator.
[0003]
Further, such an automatic transmission has a relatively large number of shift stages in order to ensure the traveling performance of a large vehicle having a large vehicle weight, and transmits power to the main transmission unit which is the original transmission. A range portion is provided as an auxiliary transmission in the upper series, and the output of the main transmission portion is shifted to two steps of high and low by this range portion to double the substantial shift step. The driver can arbitrarily select automatic shift based on the vehicle speed or accelerator operation amount and manual shift according to the change lever operation, but in either mode, the main transmission can be switched according to the next stage (target shift stage). If necessary, for example, when it is necessary to switch the range to achieve the next stage at the time of shifting up, the clutch is disconnected and the main transmission is disengaged. Then, the range portion is switched from low to high, and then the main transmission portion is placed in the next stage, and after adjusting the engine rotational speed to the rotational speed corresponding to the next stage, the clutch is connected.
[0004]
[Problems to be solved by the invention]
At the time of the above-mentioned shift up, the clutch disk side (synchronized side) in the main transmission unit continues to rotate by inertia when the clutch is disengaged, and corresponds to the next stage by the action of the synchro mechanism with the subsequent gear engagement. It is synchronized with the main shaft side (synchronization side) of lower rotation.
[0005]
At this time, the clutch disk side gradually decreases until the gear is engaged and approaches the rotational speed on the main shaft side, so that the load on the synchro mechanism is usually small. However, when the oil temperature of the transmission is low, etc., high-viscosity mission oil acts as a large rotational resistance on the clutch disc side. Since the insertion timing is delayed, as a result, the rotational speed on the clutch disk side greatly drops beyond the rotational speed on the main shaft side. Therefore, there is a problem in that the load on the synchro mechanism increases in order to raise the clutch disk side to the rotation speed on the main shaft side, and synchronization is delayed or synchronization is impossible.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to provide a transmission equipped with a sub-transmission capable of reducing the load on the synchro mechanism by preventing a decrease in the rotational speed on the clutch disk side during upshifting, thereby realizing a quick and reliable shift. It is an object of the present invention to provide a shift control apparatus.
[0007]
[Means for Solving the Problems]
To achieve the above object, in the invention of claim 1, and a transmission for transmitting the driving system of the vehicle by shifting the power of the engine, constitute a transmission, Ru switching a plurality of speed stages by the operation of the synchro mechanism A main transmission unit, a sub-transmission unit that constitutes the transmission, is arranged in series with the main transmission unit in terms of power transmission, and includes high and low gears, and a clutch that connects and disconnects power between the transmission and the engine A shift command means for issuing a shift command when the transmission needs to be shifted, a clutch control means for controlling connection / disconnection of the clutch based on the shift command of the shift command means, and a target shift stage based on a shift up command of the shift command means Is accompanied by a shift of the sub-transmission unit, and when the clutch rotational speed becomes equal to or lower than the target shift stage equivalent rotational speed during the upshift, a contact signal is sent to the clutch control means while keeping the main transmission unit in neutral. And force, then outputs a disconnection signal to the clutch control unit when the clutch rotational speed becomes the target shift stage corresponding rotational speed or higher, whereas resume transmission of the main transmission section, the clutch rotational speed during upshifting is Shift control means for shifting the main transmission section without outputting a contact signal to the clutch control means when the target gear stage equivalent rotational speed is exceeded .
[0008]
Therefore, when a shift-up with a shift of the sub-transmission unit is performed based on a target shift stage based on a command from the shift command means, and the clutch rotational speed becomes equal to or lower than the target shift stage equivalent rotational speed during the shift, the main shift is performed. The clutch is engaged based on the clutch engagement signal from the shift control means while keeping the machine part neutral. As a result, the clutch rotational speed increases due to the rotation of the engine, and when the clutch rotational speed becomes equal to or higher than the target gear speed, the clutch is disengaged and the shift of the main transmission unit is resumed. Since the clutch rotational speed is increased in this way and synchronization is performed by the synchro mechanism of the main transmission unit, the load on the synchro mechanism is reduced.
[0009]
According to a second aspect of the present invention, engine control means for controlling the rotational speed of the engine is further provided, and the shift control means is provided with the clutch engagement signal output so that the engine rotational speed becomes the target gear speed equivalent rotational speed. Is configured to output an instruction signal. Therefore, when the clutch is connected, the clutch rotational speed is quickly increased by the engine rotational speed adjusted to the target gear speed, which further reduces the load on the synchronization mechanism.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in a transmission control device for a transmission including a sub-transmission mounted on a large truck will be described.
FIG. 1 is an overall configuration diagram showing a transmission control apparatus for a transmission including 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. Thus, the rotation from the engine 2 is changed and transmitted to the drive wheel side through a propeller shaft (not shown).
[0011]
FIG. 2 is a cross-sectional view showing details of the transmission. As shown in FIG. 2, an input shaft 4 and a main shaft 5 are coaxially supported in the casing 3 of the transmission 1 so as to be individually rotatable. The shaft 4 is connected to the engine 2 via a clutch 6, and rotation is input from the engine 2 when the clutch 6 is connected.
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. The first and second splitter gears 11 and 12 mesh with the third and fourth splitter gears 14 and 15 on the counter shaft 13 supported in parallel with the main shaft 5, respectively. When the input shaft 4 is coupled to the first splitter gear 11 by switching the synchro mechanism 16 provided between the second splitter gears 11 and 12, the gear ratio of the first and third splitter gears 11 and 14. When the rotation is transmitted to the counter shaft 13 and the input shaft 4 is coupled to the second splitter gear 12, the rotation is transmitted to the counter shaft 13 with the gear ratio of the second and fourth splitter gears 12 and 15. . Accordingly, two-step shifting is performed by the splitter unit M1 configured as described above.
[0012]
In addition, a plurality of sets of transmission gears 17 and 18 (including reverse gears) that mesh with each other are disposed on the main shaft 5 and the counter shaft 13, and are synchronized with the gear 17 on the main shaft 5 side. Each transmission gear 17 is selectively coupled to the main shaft 5, and the rotation of the counter shaft 13 is transmitted to the main shaft 5 with the combined gear ratio. Then, the main transmission unit M2 as the main transmission unit configured as described above performs a four-speed shift for forward movement.
[0013]
Further, an output shaft 20 is coaxially supported behind the main shaft 5 in the casing 3, and the rear end of the output shaft 20 is connected to the propeller shaft. 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 output shaft 20, and these planetary gears 21 are ring gears disposed on the outer peripheral side. 22 and meshes with a sun gear 5 a formed on the outer periphery of the main shaft 5. A rotary ring 24 is fitted on the output shaft 20 via a bearing 23, and the outer periphery of the front part of the rotary ring 24 meshes with the inner periphery of the ring gear 22. The ring gear 22 always rotates integrally with the rotary ring 24. .
[0014]
A synchro mechanism 25 is spline-coupled to the outer periphery of the rear portion of the rotary ring 24, and as shown by a solid line, when the synchro mechanism 25 is operated forward, the rotary ring 24 is coupled to one side 3 a in the casing 3 and the ring gear 22. Since the planetary gear 21 rolls on the inner periphery of the ring gear 22 as the sun gear 5a rotates, the rotation of the main shaft 5 is decelerated and transmitted to the output shaft 20. As indicated by the alternate long and short dash line, when the synchro mechanism 25 is operated backward, the rotating ring 24 is coupled to the regulating ring 26 that is splined on the output shaft 20, and the planetary gear 21 rolls relative to the ring gear 22. Therefore, the rotation of the main shaft 5 is transmitted to the output shaft 20 at a constant speed as it is. Accordingly, the range portion M3 serving as the sub-transmission unit configured as described above performs the two-step shift.
[0015]
In the present embodiment, the shift stage is subdivided into a total of eight stages by combining the four forward speeds achieved in the main transmission part M2 with the two high and low speed shifts of the splitter part M1. Furthermore, by combining the two shifts of the high and low of the range portion M3 with the total of the eight shift stages, another eight shift stages are provided on the low speed side of the original eight shift stages, As a result, a total of 16 speeds are achieved.
[0016]
Therefore, for example, when the adjacent shift is performed such as switching between the first speed and the second speed, the main transmission section M2 is shifted with the shift of the splitter section M1, and 1 is performed as the switching between the first speed and the third speed. At the time of a step-shifting shift, the main transmission unit M2 is independently shifted without accompanying the shifting of the splitter unit M1. Further, when shifting between the low speed side and the high speed side, such as between the 8th and 9th speeds, or between the 8th and 10th speeds, any of the operations described above (along with the shifting with the switching of the splitter unit M1). In addition to the no shift), the shift of the range portion M3 is executed.
[0017]
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 synchro mechanism 19 of the main transmission unit M2 by compressed air from the air tank 32 in accordance with switching of a large number of built-in switching valves, and changes the gear stage. Switch. The air tank 32 is connected to a splitter cylinder 34 through a pair of switching valves 33. The splitter cylinder 34 is synchronized with the synchronizing mechanism 16 (see FIG. 2) is operated to switch the gear position. Similarly, the air tank 32 is connected to the range cylinder 36 via a pair of switching valves 35. The range cylinder 36 is connected to the sync mechanism 25 of the range portion M3 via a shift fork 36a according to the switching of the switching valve 35. Operate to change the gear position. Further, the air tank 32 is connected to a clutch booster 38 via a switching valve 37, and the clutch booster 38 connects and disconnects the clutch 6 according to the switching of the switching valve 37.
[0018]
On the other hand, an engine control unit (hereinafter referred to as an engine ECU) 41 as an engine control means is installed in the passenger compartment, and an accelerator sensor 42 for detecting the amount of accelerator operation by the driver, an engine rotation speed on the input side of the engine ECU 41. An engine rotation speed sensor 43 for detecting Ne and a vehicle speed sensor 44 for detecting the vehicle speed are connected, and an electronic governor 45 provided in the engine 2 is connected to the output side. The engine ECU 41 operates the engine 2 by controlling the fuel injection amount by the electronic governor 45 and the injection timing by a timer (not shown) based on detection signals input from the sensors.
[0019]
The engine ECU 41 is connected to a transmission command unit, a clutch control unit, and a transmission control unit (hereinafter referred to as a transmission ECU) 46 as a transmission control unit so that they can communicate with each other. Are the gear shift unit 31, the splitter sensor 47 for detecting the shift position of the splitter unit M1, the range sensor 48 for detecting the shift position of the range unit M3, and the rotational speed of the clutch disk that rotates together with the input shaft 4 (hereinafter referred to as the clutch rotational speed). A clutch rotational speed sensor 49 for detecting Nc1, a clutch stroke sensor 50 for detecting the operation stroke of the clutch booster 38, and a change lever unit 51 operated by the driver are connected. Further, the gear shift unit 31, the switching valve 33 of the splitter unit M1, the switching valve 35 of the range unit M3, and the switching valve 37 of the clutch 6 are connected to the output side of the transmission ECU 46.
[0020]
The change lever unit 51 is configured to be capable of instructing switching of modes such as the D range and the M range, and further selecting a gear position in the M range, and the transmission ECU 46 shifts according to the switching state of the change lever unit 51. The shift operation of the machine 1 and the connection / disconnection operation of the clutch 6 are performed. That is, when the change lever unit 51 is switched to the D range, automatic shift is performed, the target shift stage is determined according to the map from the vehicle speed and the accelerator operation amount, and the change lever unit 51 is switched to the M range. When the vehicle is in a manual shift, the shift stage instructed by the driver using the change lever unit 61 is regarded as the target shift stage. And based on the information from the gear shift unit 31, the splitter sensor 47, and the range sensor 48, while performing switching operation of the splitter part M1, the main transmission part M2, and the range part M3 by each switching valve 33,35,37, In parallel with this, the clutch 6 is connected / disconnected based on information from the clutch stroke sensor 50 to achieve the above-described target shift speed.
[0021]
The transmission ECU 46 according to the present embodiment executes a so-called double clutch when the upshift is executed with the switching of the range unit M3 in any of the above-described D range mode and M range mode. The load on the synchro mechanism 19 is reduced. As described above, when shifting the range unit M3, the splitter unit M1 is switched at the same time (for example, between the 8th and 10th speeds), and the splitter unit M1 is not switched (for example, between the 8th and 9th speeds). However, here, 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.
[0022]
3 and 4 are flowcharts showing a shift control routine executed by the transmission ECU. First, the transmission ECU 46 determines whether or not the shift is upshifted from the relationship between the current gear stage and the next stage (target shift stage) in step S2, and determines whether or not the shift is accompanied by switching of the range unit M3 in step S4. Determine. If NO (negative) is determined in step S2 or step S4, the clutch 6 is disconnected in step S6, the gear shift of the main transmission unit M2 is executed in step S8, and the gear shift is performed in step S10. Based on the information from the unit 31, it is determined whether or not the gear removal has been completed. If the determination is YES (affirmative) due to the completion of gear removal, gears are engaged in the next stage in step S12, and it is determined whether or not gear engagement is completed in step S14. If the determination is YES due to the completion of gear engagement, a command is output to the engine ECU 41 in step S16 to adjust the engine rotational speed Ne to the clutch rotational speed Nc2 corresponding to the next stage, and in the subsequent step S18, the clutch 6 is connected, End the routine.
[0023]
On the other hand, when both of the determinations in step S2 and step S4 are YES, that is, when the upshift is accompanied by the switching of the range portion M3, the routine proceeds to step S20 where the clutch 6 is disconnected, and in step S22 the main transmission portion M2 The gear removal is executed, and it is determined whether or not the gear removal is completed in step S24. If the determination is YES due to the completion of gear removal, the range portion M3 is switched from low to high in step S26, and it is determined whether or not the range portion M3 has been switched in step S28. If the determination is YES upon completion of switching, it is determined whether or not the clutch rotational speed Nc1 detected by the clutch rotational speed sensor 49 in step S30 is less than a value obtained by subtracting a predetermined value A from the clutch rotational speed Nc2 corresponding to the next stage. To do. If the determination is NO, that is, if the clutch rotational speed Nc1 has not decreased so much, the routine proceeds to step S12 where the gear is engaged to the next stage, and the clutch 6 is connected in step S18 through step S14 and step S16.
[0024]
If the determination in step S30 is YES, that is, if the clutch rotational speed Nc1 is greatly reduced, the process proceeds to step S32 to connect the clutch 6, and in step S34, the clutch rotational speed Nc2 corresponding to the next stage is set to a predetermined value. A command is output to the engine ECU 41 so as to increase the engine rotational speed Ne to a value obtained by adding B. In subsequent step S36, it is determined whether or not the clutch rotational speed Nc1 is less than a value obtained by subtracting a predetermined value C from the clutch rotational speed Nc2 corresponding to the next stage.
[0025]
Since the initial clutch rotation speed Nc1 is less than the value obtained by subtracting the predetermined value C from the clutch rotation speed Nc2, the determination in step S36 is YES, but the clutch rotation is performed together with the engine rotation speed Ne based on the command in step S34. Since the speed Nc1 continues to increase, a determination of NO is made soon in step S36, and the clutch 6 is disconnected in step S38. Thereafter, in the same manner as described above, the gear is engaged in the next stage in step S12, and the clutch 6 is connected in step S18 through steps S14 and S16.
[0026]
When shifting up with the switching of the range unit M3 as described above, since the switching operation (step S26) of the range unit M3 is applied during the shifting of the main transmission unit M2, the gear of the main transmission unit M2 is correspondingly increased. The timing of insertion (step S12) is delayed, and during that time, the clutch disk that is rotating inertially decreases, and especially when the oil temperature is low, the transmission oil acts as a large rotational resistance on the clutch disk side, so the clutch rotational speed Nc1 is the next stage. May fall significantly exceeding the rotational speed Nc2 corresponding to. As described above, in the speed change control device according to the present embodiment, in such a case, the clutch 6 is once connected, and the clutch rotational speed Nc1 is increased to the vicinity of the clutch rotational speed Nc2 together with the engine rotational speed Ne. Execute gearing to. Therefore, the load on the synchro mechanism 19 when synchronizing the clutch disk side (synchronized side) with the main shaft 5 side (synchronous side) can be greatly reduced, thereby preventing the occurrence of synchronization delay or synchronization failure. Thus, a quick and reliable shift can be realized.
[0027]
Further, in this way, the command is output to the engine ECU 41 side to positively increase the engine rotational speed Ne, and accordingly, the clutch rotational speed Nc1 is rapidly increased and the load on the synchro mechanism 19 is further reduced. be able to.
This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above-described embodiment, the shift control device for the transmission 1 mounted on a large truck is embodied, but the vehicle type is not limited as long as a transmission including a sub-transmission is mounted. The present invention may be embodied in a shift control device for a transmission mounted on a passenger car.
[0028]
Further, the transmission 1 of the above embodiment includes the splitter unit M1 as a transmission mechanism in addition to the main transmission unit M2 and the range unit M3. However, the splitter unit M1 is not necessarily provided, and the main transmission unit M2 and the range are not necessarily provided. You may actualize in the transmission provided only with the part M3.
Further, in the above embodiment, the engine speed Ne is positively increased when the clutch is engaged, but this engine control is not necessarily executed. The engine rotational speed Ne at the time of upshifting does not rapidly decrease. On the other hand, in the case of upshifting, the clutch rotational speed Nc2 corresponding to the next stage is a lower value. Even simply by connecting, the clutch rotational speed Nc1 increases and approaches the clutch rotational speed Nc2 corresponding to the next stage. In particular, in a large truck such as this embodiment, the clutch rotational speed Nc2 corresponding to the next stage at the time of upshifting is considerably low due to the regular use of the low rotational range, and the clutch is engaged due to slow rotation drop in terms of engine characteristics. Since there are many cases where the engine speed has not dropped to idle rotation at this point, it is possible to sufficiently reduce the synchro load by increasing the clutch rotation speed Nc1 by connecting the clutch.
[0029]
【The invention's effect】
As described above, according to the shift control apparatus for a transmission including the sub-transmission according to the first aspect of the present invention, the clutch rotational speed is equal to or less than the target shift speed equivalent rotational speed when the sub-transmission unit is shifted up. When the clutch becomes engaged, the clutch rotational speed is increased to a value equal to or higher than the target gear stage equivalent rotational speed and then the clutch is disengaged to shift the main transmission section. Thus, it is possible to prevent a delay in synchronization or a situation where synchronization cannot be achieved, thereby realizing a quick and reliable shift.
[0030]
Further, according to the transmission control device for a transmission including the sub-transmission according to the second aspect of the invention, since the engine rotational speed is positively increased, the clutch rotational speed is rapidly increased with this, The synchronization load can be further reduced.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing a transmission control device for a transmission including an auxiliary transmission according to an embodiment.
FIG. 2 is a cross-sectional view showing details of the transmission.
FIG. 3 is a flowchart showing a shift control routine executed by the transmission ECU.
FIG. 4 is a flowchart showing a shift control routine executed by the transmission ECU.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Transmission 2 Engine 6 Clutch 41 Engine ECU (engine control means)
46 Transmission ECU (shift command means, clutch control means, shift control means)
M2 main transmission (main transmission)
M3 range section (sub-transmission section)
Ne Engine speed Nc1 Clutch speed

Claims (2)

A transmission for shifting the power of the engine and transmitting it to the drive system of the vehicle;
Constitute the transmission, the main transmission section Ru switching a plurality of speed stages by the operation of the synchro mechanism,
A sub-transmission unit that constitutes the transmission, is arranged in series with the main transmission unit on power transmission, and includes high and low gear stages;
A clutch for connecting / disconnecting power between the transmission and the engine;
Shift command means for issuing a shift command when shifting of the transmission is necessary;
Clutch control means for controlling connection / disconnection of the clutch based on a shift command of the shift command means;
When the target shift stage according to the shift-up command of the shift command means is accompanied by a shift of the sub-transmission unit, the main shift is performed when the clutch rotational speed becomes equal to or lower than the target shift stage equivalent rotational speed during the shift-up shift. A contact signal is output to the clutch control means while keeping the machine part neutral, and then a disconnect signal is output to the clutch control means when the clutch rotational speed becomes equal to or higher than the target gear speed equivalent rotational speed. While the transmission of the transmission unit is resumed , the main transmission unit does not output a contact signal to the clutch control means when the clutch rotational speed exceeds the target gear stage equivalent rotational speed during the upshift. A shift control apparatus for a transmission comprising a sub-transmission, comprising: Engine control means for controlling the rotational speed of the engine;
The shift control means includes
2. The transmission having an auxiliary transmission according to claim 1, wherein an instruction signal is output to the engine control means together with the clutch engagement signal output so that the engine rotational speed becomes the target gear speed equivalent rotational speed. Shift control device.

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