JP2002130458A - Vehicular gear transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular gear transmission for obtaining smooth shift operation causing no chattering of a gear by meshing the gear in the always optimal timing regardless of a change in inertial mass and resistance of the gear transmission and frictional force of an auxiliary shaft brake. SOLUTION: In this vehicular gear transmission having a main shaft 22 coaxially arranged with an input shaft 9, an auxiliary shaft 40 rotatably by interlocking with the main shaft 22 via a shift gear train, the auxiliary shaft brake 12 arranged on the auxiliary shaft 40, a shift actuator 66 for interlocking with control of the auxiliary shaft brake 12, the input shaft 9 for rotating by interlocking with the auxiliary shaft 40 via an intermediate gear, and a clutch mechanism 4 for rotatably joining the input shaft 9 to a crankshaft 3 of an engine, the operating timing of the shift actuator 66 can be varied on the basis of a rotational change rate of the auxiliary shaft 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear transmission for a synchro-less vehicle, and the gear noise and the like are always generated at an optimum time regardless of the inertial mass and resistance of the gear transmission and the frictional force of the countershaft brake. The present invention relates to a vehicle gear transmission capable of obtaining a smooth shifting operation that does not occur.

[0002]

2. Description of the Related Art In a synchronous-less gear transmission without a synchronization mechanism (synchronizer), gear shifting operation is automated because it is difficult to manually adjust (synchronize) gears during gear shifting. In a synchronous-less gear transmission, a sub-shaft brake such as a wet multi-plate clutch is attached to a rotating part that is directly connected to a synchronized side gear such as a sub-shaft (counter shaft) or interlocked via a gear. To reduce the time required. In other words, during the shift-up shift operation, the rotational speed of the synchronized gear before the shift is higher than the rotational speed of the main shaft, so that the rotational speed of the synchronized gear is reduced to the rotational speed of the main shaft in advance for the shift operation.

[0003] As disclosed in, for example, Japanese Patent Application Laid-Open No. 7-167278, a conventional control method of a countershaft brake includes the following.
The operation and release of the countershaft brake are performed based on the following conditions. That is, when the clutch mechanism is shut off and the shift position is in the neutral position, the sub-shaft brake is activated if the rotation difference between the synchronized gear and the main shaft is larger than a, and the sub-shaft brake is released if the above conditions are not satisfied. . Here, assuming that a is an arbitrary number of rotations, for example, if a is 200, when the rotation difference between the synchronized gear and the main shaft becomes 200 rpm, the sub shaft brake is released. Next, the shift operation is performed by the shift actuator in conjunction with the sub shaft brake. Even if the rotation speed of the synchronized gear is rapidly reduced by the countershaft brake, if the operation timing of the shift actuator is too early or too late, the rotation difference between the synchronized gear and the main shaft will change.
Conventionally, the shift actuator is controlled based on the following conditions.

Assuming that the rotation difference between the synchronized gear and the main shaft after the clutch mechanism is cut off is b, when the rotation difference becomes smaller than b, the shift actuator is driven to engage the transmission gear, and the above condition is satisfied. If the condition is not satisfied, the transmission gear is held at the neutral position. Here, b is an arbitrary rotation speed. For example, if b is 100, the rotation difference between the synchronized gear and the main shaft is 10
0 rpm, allowing the gears to mesh. As described above, the operation timings of the sub-shaft brake and the shift actuator are set by the values of a and b relating to the rotation difference between the synchronized gear and the main shaft.

However, if the oil agitation resistance of the gears of the gear transmission changes due to fluctuations in the oil temperature of the gear transmission (the temperature of the lubricating oil filled in the transmission case), the rotational deceleration of the countershaft is reduced. (The degree of decrease in rotation speed) also changes,
If the values of a and b are always kept constant, the operation timings of the sub shaft brake and the shift actuator may be shifted. For example,
The oil agitation resistance of the gear transmission at cryogenic temperatures is much greater than that at room temperature, so setting the values of a and b to optimal values at room temperature will activate the countershaft brake and shift actuator at cryogenic temperatures. The time is late. Further, during high-speed running, the oil temperature of the gear transmission increases, and the oil stirring resistance of the gear transmission decreases, so that the operating timing of the sub-shaft brake and the shift actuator is advanced.

[0006]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to always engage a gear at an optimum time regardless of the inertial mass and resistance of a gear transmission, a change in frictional force of a countershaft brake, and the like. Accordingly, it is an object of the present invention to provide a vehicular gear transmission capable of obtaining a smooth gear change operation without gear noise or the like.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is directed to a clutch mechanism for rotatingly connecting an input shaft to a crankshaft of an engine, and a sub-mechanism which rotates in conjunction with the input shaft via a relay gear. A main shaft that is arranged coaxially with the input shaft and that transmits the rotation of the sub shaft via a speed change gear train;
In a vehicle gear transmission having a sub shaft brake connected to the sub shaft and a shift actuator interlocked with control of the sub shaft brake, a rotation speed sensor is provided on the sub shaft, and rotation of the sub shaft is The operation time of the countershaft brake is made variable based on the number.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the above-mentioned values of a and b are changed according to the rotational deceleration of the countershaft (counter shaft) at the time of shift-up, so that the optimum value is always obtained regardless of the state of the gear transmission. Operate the countershaft brake and shift actuator at the appropriate time.

The response time when switching the sub-shaft brake from the operating state to the released state and the time from when the gear meshing permission is received to when the shift actuator actually meshes the gear are determined by the state of the gear transmission. Not much affected. That is, it is considered that the operation delays of the sub shaft brake and the shift actuator are almost constant. Therefore, when the rotation deceleration of the sub shaft is large, the sub shaft brake is released early and the shift actuator is operated, while when the rotation deceleration of the sub shaft is small, the sub shaft brake is released later. By operating the shift actuator, the gears can always be engaged at the optimal time.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG.
The rotation of the crankshaft 3 is transmitted through the clutch mechanism 4 to the input shaft 9.
The rotation of the main shaft 22 is transmitted to the propulsion shaft 52 via the universal joint 51, and the rotation of the propulsion shaft 52 is transmitted to the left and right wheels via a known differential gear mechanism.
When the clutch mechanism 4 presses the clutch plate 5 connected to the input shaft 9 to the flywheel 10 connected to the end of the crankshaft 3 with the pressing plate 6, the rotation of the crankshaft 3 is transmitted to the input shaft 9. A base end of the pressing arm 7 is supported by a release bearing 8 slidably and rotatably supported by the input shaft 9, and an intermediate portion of the pressing arm 7 is supported by the pressing plate 6. Therefore, the release bearing 8 is moved from the state in which the clutch is cut off as shown in the figure.
Is moved to the right, the pressing arm 7 receives the force of a spring (not shown), and the pressing plate 6 presses the clutch plate 5 against the flywheel 10.

The transmission 21 includes an input shaft 9 connecting an input gear 31 to an end, an output shaft or main shaft 22 supported by bearings at the end of the input shaft 9 and a rear wall of the transmission case, and an input gear 31. And an intermediate shaft or countershaft 40 that couples a gear 41 that always meshes. The main shaft 22 has gears 32 to 38
Are freely rotatably supported, and the gears 32-38 are configured to be rotatably coupled to the main shaft 22 by known clutches 23-26. Gears 42 to 48 meshing with the respective gears 32 to 38 are respectively coupled to the countershaft 40. A reverse gear 47a meshes with the gear 47 and the gear 37.

Each of the clutches 23 to 26 is engaged with a clutch hub 70 connected to the main shaft 22, dog teeth provided on gears on both sides of the clutch hub 70, and the clutch hub 70.
And a clutch sleeve 24a (see FIG. 2) that selectively meshes with one of the dog teeth provided on the gears on both sides.

As shown in FIGS. 2 and 3, an annular groove 61 is formed on the outer peripheral surface of each clutch sleeve 24a, and a bifurcated fork 62 supported by the shift rod 24b has an annular groove 6 formed therein.
1 is engaged. An arm 64 is supported by a rod 65 projecting from the three-position shift actuator 66 so as to be rotatable about the rod 65, and the arm 64 is moved to a desired shift rod 2
It can be engaged with the groove 63 formed in 3b-26b. Shift rods 23b to 26b for driving the clutches 23 to 26 to three positions in the axial direction of the main shaft 22 are arranged in parallel on the upper wall of the transmission case so as to approach in parallel with each other.
b to 26b so as to selectively engage with the groove 63.
Is configured to be rotated by a not-shown select actuator.

According to the present invention, for example, in the case of a shift-up shift operation from the fourth gear, the clutch mechanism 4 is shut off to release the rotational connection between the crankshaft 3 and the input shaft 9, and then the shift actuator 66 Speed clutch 24
To the neutral position shown in FIG.
6, the clutch 24 of the current gear position is moved from the neutral position by 5
The gear 33 (the countershaft 4
0, which is determined by the number of rotations of the clutch shaft 70 of the main shaft 22, that is,
The countershaft brake 12 is provided at the end of the countershaft 40 to reduce the rotation speed of the countershaft.

The countershaft brake 12 has a plurality of cylinders 14 connected to the front wall of the transmission case and fitted with a piston 13 to form an oil chamber at the left end, and a plurality of splines supported on the inner peripheral surface of the cylinder 14. A friction disk spline-supported on the sub shaft 40 is disposed between the annular friction plates. When the piston 13 is moved rightward by the hydraulic pressure introduced into the oil chamber, the friction between the friction plate of the cylinder 14 and the sub shaft 40 is increased. The disk and the disk are frictionally engaged to apply a braking torque to the countershaft 40.

For example, in a shift-up shift operation from the fourth gear to the fifth gear, all the clutches 23 to 26 are in the neutral position (release position) after the clutch mechanism 4 is shut off, and the rotational difference between the clutch hub 70 and the gear 33 Is larger than a, the countershaft brake 12 is operated. Next, when the rotation difference between the clutch hub 70 and the gear 33 becomes b, the shift rod 66 is shifted by the shift actuator 66.
4b to drive the clutch sleeve 24a of the clutch 24.
Is engaged with the clutch hub 70 and the dog teeth of the gear 33.
When controlling the clutches 23 to 26 and the shift actuator 66, as shown in FIGS.
And b are changed in accordance with the temperature of the lubricating oil filled in the case of the gear transmission 21, that is, the oil temperature.

As shown in FIGS. 4 and 5, according to the present invention, the rotational speeds of the sub shaft 40 (desired transmission gear) and the main shaft 22 (clutch hub 70) after the clutch mechanism 4 is cut off are detected, and the sub shaft is detected. When the rotation difference between the main shaft 22 and the main shaft 22 is larger than a, the sub-shaft brake 12 is operated. When the rotation difference between the sub-shaft 40 and the main shaft 22 becomes a, the sub-shaft brake 12 is released. When the rotation difference between 40 and the main shaft 22 becomes b, a gear meshing permission signal is generated in accordance with the oil temperature of the gear transmission 21 at that time, and the shift actuator 66 is driven. The shift actuator 66 is driven in a timely manner based on the change in the number of revolutions of the sub shaft 40, so that the gears can be smoothly meshed by the speed change operation.

When the rotational deceleration of the sub shaft 40 is large (when the oil temperature is low), the sub shaft brake 12 and the shift actuator 66 are actuated earlier so that the gear synchronization timing and the shift actuator can be changed. 66 can be synchronized. When the rotational deceleration of the sub shaft 40 is small (when the oil temperature is high), the sub shaft brake 12 and the shift actuator 66 are operated later, so that the gear synchronization timing and the shift actuator 66 can be synchronized.

FIG. 6 is a flow chart of a control program for performing the above-mentioned control by an electronic control device comprising a microcomputer. In FIG. 6, p11 to p21 represent each step of the control program. This control program is repeatedly executed at predetermined time intervals. The control program is started at p11, and it is determined whether or not a shift-up shift operation is performed based on a rotation difference between the clutch hub 70 and the main shaft 22 immediately after the clutch mechanism 4 is shut off at p12. In the case of a shift down shift operation, the process proceeds to p21, and in the case of a shift up shift operation, the rotational deceleration of the sub shaft 40 is obtained in p13. Actually, the value is obtained by differentiating the value of the rotation speed sensor disposed on the sub shaft 40.

At p14, the values of a and b corresponding to the rotational deceleration of the counter shaft 40 (or the oil temperature of the transmission) are obtained from the control map shown in FIGS. At p15, it is determined whether or not the rotation speed of the sub shaft 40 (or the oil temperature of the transmission) is larger than a. If the rotation speed of the sub shaft 40 (or the oil temperature of the transmission) is larger than a, the sub shaft brake 12 is operated at p16, and the program proceeds to p18. When the rotation speed of the sub shaft 40 (or the oil temperature of the transmission) is smaller than a, the sub shaft brake 12 is released at p17, and p
At 18, the rotation speed of the countershaft 40 (or the oil temperature of the transmission) becomes b (a
> B) is determined. When the rotation speed of the countershaft 40 (or the oil temperature of the transmission) is larger than b, p
At 19, meshing of the gears is prohibited, and the program proceeds to p21. If the rotation speed of the countershaft 40 is smaller than b, the gear meshing is permitted at p20, the gearshift operation is performed by the shift actuator 66, and the process ends at p21.

[0021]

As described above, the present invention provides a clutch mechanism for rotatingly connecting an input shaft to a crankshaft of an engine, a sub-shaft which rotates in conjunction with the input shaft via a relay gear, and a shaft coaxial with the input shaft. A vehicle having a main shaft arranged and transmitting rotation of the sub shaft through a transmission gear train, a sub shaft brake connected to the sub shaft, and a shift actuator interlocked with control of the sub shaft brake. In the gear transmission, the rotation speed sensor is provided on the countershaft and the operation time of the countershaft brake is made variable based on the rotation speed of the countershaft. Regardless of the oil temperature, the amount of inertia of the gears and the main and sub shafts, etc.), the sub shaft brake and the shift actuator can always be operated at the optimal time by a constant control law.

Since the shift actuator operates at an optimal time (the shift actuator operates at the same time as the gears are synchronized), gear noise is prevented and wear of the gear teeth of the transmission gear is also prevented.

Since a common control law can be used irrespective of the type of gear transmission, the electronic control unit can be used in common (there is no need to change the settings of switches and the like of the electronic control unit depending on the type of gear transmission).

[0024] Variations in the braking force of the sub shaft brake and a decrease in the braking performance can be tolerated.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a schematic configuration of a vehicle gear transmission according to the present invention.

FIG. 2 is a side view of a speed change operation mechanism of the vehicle gear transmission.

FIG. 3 is a plan view of a speed change operation mechanism of the vehicle gear transmission.

FIG. 4 is an explanatory diagram showing an operation of the vehicle gear transmission.

FIG. 5 is an explanatory diagram showing an operation of the vehicle gear transmission.

FIG. 6 is a flowchart of a control program for performing a shift operation of the vehicle gear transmission by an electronic control unit.

FIG. 7 is a diagram showing rotation differences a and b determined according to the rotation deceleration of the sub shaft.

FIG. 8 is a diagram showing rotation differences a and b determined according to the oil temperature of the vehicle gear transmission.

FIG. 9 is a diagram illustrating an operation timing of a shift actuator determined according to an oil temperature of a vehicle gear transmission.

[Explanation of symbols]

2: Internal combustion engine 3: Crankshaft 4: Clutch mechanism
9: input shaft 10: flywheel 12: counter shaft brake 13: piston 14: cylinder 21: gear transmission 22: main shaft 23-26: clutch 23b-26
b: Shift rod 24a: Clutch sleeve 31: Input gear 32-3
8: Gear 40: Counter shaft 41: Relay gear 42-48: Gear 54: Oil temperature sensor 61: Annular groove 62: Hawk 63: Groove 64: Arm
66: Shift actuator 70: Clutch hub

Claims (6)

[Claims] A clutch mechanism for rotatably coupling an input shaft to a crankshaft of an engine; a subshaft interlockingly rotating via the input shaft and a relay gear; and a rotation of the subshaft arranged coaxially with the input shaft. A main shaft transmitted through a transmission gear train, a sub shaft brake connected to the sub shaft, and a shift actuator interlocked with control of the sub shaft brake. A gear transmission for a vehicle, wherein a rotation speed sensor is provided on a shaft, and an operation time of the sub shaft brake is made variable based on a change rate of a rotation speed of the sub shaft. 2. The operation time of the sub shaft brake is set short when the rotation deceleration of the sub shaft is large, and the operation time of the sub shaft brake is set long when the rotation deceleration is small. 2. The vehicle gear transmission according to claim 1. 3. A control map having an oil temperature sensor for measuring an oil temperature of lubricating oil of the transmission, wherein an oil temperature is set on a horizontal axis, and an operation time of the sub-shaft brake is set on a vertical axis. Item 4. A vehicle gear transmission according to item 1. 4. A clutch mechanism for rotatably coupling an input shaft to a crankshaft of an engine, a subshaft interlockingly rotating via the input shaft and a relay gear, and a rotation of the subshaft disposed coaxially with the input shaft. A main shaft transmitted through a transmission gear train, a sub shaft brake connected to the sub shaft, and a shift actuator interlocked with control of the sub shaft brake. A gear transmission for a vehicle, wherein an operation timing of the shift actuator is made variable based on a rotation deceleration of a shaft. 5. The operation timing of the shift actuator is set earlier when the rotation deceleration of the sub shaft is large, and the operation timing of the shift actuator is set later when the rotation deceleration is small.
The vehicle gear transmission according to claim 4. 6. A control map in which an oil temperature sensor for measuring an oil temperature of lubricating oil of the transmission is provided, and an oil temperature is set on a horizontal axis, and an operation timing of a shift actuator is set on a vertical axis. Item 5. A vehicle gear transmission according to item 4.