JPH06323419A - Shift control method for vehicle - Google Patents

Abstract

PURPOSE:To eliminate the condition that torque is lost during shifting by disengaging a first speed clutch in a half engaging condition while the clutch is disengaged completely after a second speed clutch is engaged in a half engaged condition, and the second speed clutch is engaged completely. CONSTITUTION:In a transmission 10 a controller 10B controls the ECMV valve 10C of solenoid valve according to operation of a speed change lever 10A, and thus oil pressure is regulated so that the multiple disc clutches 22, 23, 27 to 29 of gear main body mechanism 10D are disengaged. As a result, the rotation force input from the output shaft 12 of an engine 11 to the input shaft 13 of the mechanism 10D is transmitted to the output shaft 14 after shifting is made. The first speed clutch is disengaged to the half engaging condition and the second speed clutch is engaged for the half engaging condition, and thereafter the first speed clutch is disengaged completely and the second speed clutch is engaged completely. Torque exhaustion during shifting or hock is prevented from generating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle for performing forward and backward and speed stage shift control by connecting and disconnecting forward and reverse traveling direction clutches and at least first and second speed clutches. The present invention relates to a shift control method, and particularly to a shift control method suitable for use in vehicles of construction machines such as power shovels, shovel dozers, bulldozers, wheel loaders, and trucks (including dump trucks).

[0002]

2. Description of the Related Art Conventionally, as a shift control method for a vehicle of this type, it is assumed that the forward and reverse traveling direction clutches are load clutches, and the above-mentioned progression is performed when shifting in the same traveling direction or in the reverse traveling direction. The forward / backward movement and the shift control of the speed stage by connecting and disconnecting the directional clutch and the speed clutch are performed as follows. First, the speed clutch on the disengagement side is disengaged, and then the advancing or reverse travel direction clutch connected thereto is disengaged.
Next, the speed clutch on the coupling side is engaged, and then the forward or reverse traveling direction clutch is engaged.

[0003]

However, each coupling of the traveling direction clutch and the speed clutch as described above,
In the case of forward / backward shift and speed-shift shift control by disconnection, torque cutoff occurs during the shift, shock is generated and riding comfort deteriorates, and especially when shifting in the same traveling direction, the vehicle speed decreases. Therefore, there is a problem that work efficiency is deteriorated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a shift control method for a vehicle in which at least comfortable riding is possible without causing torque cutoff during a shift, with the object of solving such problems.

[0005]

According to a first aspect of the present invention, there is provided a load clutch in which a traveling direction clutch is excellent in impact resistance, wear resistance, heat resistance, etc. as compared with a speed clutch. In order to achieve the above-mentioned object, the forward and backward traveling direction clutches and at least the first and second speed clutches are engaged and disengaged to move forward and backward. And (a) disengaging the first speed clutch on the disengagement side to the semi-engaged state and simultaneously disengaging the second speed clutch on the disengagement side to the semi-engaged state. The first step of combining and (b)
And a second step of completely disengaging the first speed clutch in the semi-engaged state and completely engaging the second speed clutch in the semi-engaged state. In this case, the semi-engaged state of the first speed clutch is the second engaged state.
It is preferable that the speed clutch is in the semi-engaged state in which the static torque transmission force is larger than that in the semi-engaged state.

When shifting the vehicle in the same traveling direction, in the second step, the traveling direction clutch is first disengaged to the semi-engaged state, and the first speed clutch in the semi-engaged state is completely disengaged. Then, the second speed clutch in the semi-engaged state may be gradually and completely engaged, and the advancing clutch in the semi-engaged state may be gradually and completely engaged and returned. In this case, the semi-engaged state of the first speed clutch, the semi-engaged state of the second speed clutch and the semi-engaged state of the traveling direction clutch are sequentially semi-engaged states in which the static torque transmission force is small. It is preferable. In particular, when the traveling direction clutch is a load clutch as described above, when the second speed clutch and the traveling direction clutch are gradually and completely coupled, the second speed clutch is compared with the traveling direction clutch. It is good that they are prioritized and gradually combined completely.

Further, when shifting the vehicle in the reverse traveling direction, in the second step, first, one traveling direction clutch on the disengagement side is completely disengaged, and the first speed clutch in the semi-engaged state is completely disengaged. It may be disengaged, and then the second speed clutch in the semi-engaged state may be gradually and completely engaged, and the other traveling direction clutch on the engagement side may be gradually and completely engaged. In particular, in the case where the traveling direction clutch is a load clutch similar to the above, the second clutch
When the first speed clutch and the other traveling direction clutch are gradually and completely engaged, the second speed clutch is preferably prioritized over the traveling direction clutch and gradually and completely engaged.

[0008]

According to the first aspect of the present invention, the first speed clutch on the disengagement side is disengaged to the semi-engaged state when the shift control of the speed stage is performed from the first speed clutch to the second speed clutch. In the state, the second speed clutch on the coupling side is engaged to the semi-engaged state, and thereafter the first speed clutch in the semi-engaged state is completely disengaged.
Torque is not cut off during the shift.

A shift control method for a vehicle according to the second aspect of the present invention is
It is suitable when shifting the vehicle in the same traveling direction, especially when the speed clutch is configured as a load clutch having excellent impact resistance, wear resistance, heat resistance, etc. as compared with the traveling direction clutch. In order to achieve the above object, a shift control of a vehicle for performing forward / backward and speed stage shift control by connecting and disconnecting forward and backward traveling direction clutches and at least first and second speed clutches. In the method, (a) a first step of disengaging the traveling direction clutch to a semi-engaged state and engaging a second speed clutch of the engaging side to a semi-engaged state; and (b) a first speed of the disengaging side first. Completely disengage the clutch, then fully reengage the semi-engaged advancing clutch and return the semi-engaged second speed clutch. It is to comprise a second step of binding to. In this case, the semi-engaged state of the traveling direction clutch is preferably a semi-engaged state in which the static torque transmission force is larger than the semi-engaged state of the second speed clutch.

The speed change control method for a vehicle according to the third aspect of the present invention is suitable for speed change in the reverse direction of the vehicle, particularly when the speed clutch is configured as a load clutch as described above. In order to achieve the above object, a shift control method for a vehicle for performing forward / backward and speed stage shift control by connecting and disconnecting a forward direction or reverse direction traveling direction clutch and at least first and second speed clutches. In (a), one of the traveling direction clutches is disengaged to a semi-engaged state, and the second speed clutch on the engaging side is engaged to the semi-engaged state, and (b) first the disengagement side first clutch. Completely disengage the speed clutch, completely disengage one of the semi-engaged advancing clutches, and then fully engage the other advancing clutch. Also it is to comprise a second step to completely couple the second speed clutch of the semi-coupling state. In this case, it is preferable that the semi-engaged state of the one traveling direction clutch is a semi-engaged state in which the static torque transmission force is larger than the semi-engaged state of the second speed clutch.

[0011]

According to the first and second aspects of the present invention, when the shift control of the speed stage is performed from the first speed clutch to the second speed clutch, the second speed clutch on the coupling side is brought into a semi-engaged state. The first side of the cutting side in the state of being joined up to
Since the speed clutch is completely disconnected, there is no torque cut during the shift.

When the speed clutch is a load clutch as described above, in the second aspect of the present invention, in the second step, the traveling clutch in the semi-engaged state and the first clutch in the semi-engaged state are engaged. It is preferable that the two speed clutches are gradually engaged when they are completely engaged, and the traveling direction clutch is preferentially engaged and gradually engaged as compared with the second speed clutch. Further, in the third aspect of the present invention, in the second step, the other traveling direction clutch and the second speed clutch in the semi-engaged state are gradually engaged when completely engaged, and the other traveling direction clutch is It may be prioritized and progressively engaged as compared to the second speed clutch.

The traveling direction clutch is a traveling direction clutch for forward traveling or reverse traveling. When the one traveling direction clutch is a traveling traveling direction clutch, the other traveling direction clutch is for traveling in the backward traveling direction. When the one traveling direction clutch is a reverse traveling traveling direction clutch, the other traveling direction clutch is a forward traveling traveling direction clutch.

Further, the first and second speed clutches are
It is a speed clutch that can be selected from the first speed clutch, the second speed clutch, and the like as an alternative without overlapping each other.

The traveling direction clutch and the speed clutch may be multi-plate clutches which are hydraulically pressure-bonded, released, engaged, and disengaged.

Other objects of the present invention will become apparent from the detailed description given below. However, while the detailed description and specific examples describe the most preferred embodiments, various changes and modifications within the spirit and scope of the invention will be apparent to those skilled in the art from the detailed description, and It is provided only as an example.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of the vehicle shift control method according to the present invention will be described with reference to the drawings in which the forward and reverse traveling direction clutches are load clutches. First, FIG. 1 showing a schematic configuration.
In the above, the transmission 10 according to the present embodiment has three forward gears and three reverse gears. In addition, the transmission 10
Is a speed lever 10A operated by an operator,
A controller 10B that controls gear shifting by operating the speed lever 10A, and an ECMV valve (Electric Control Modula-ting Valve; USPA) that is an electromagnetic solenoid valve that adjusts hydraulic pressure according to a control instruction of the controller 10B.
S. N. 534737, 965622, 775994,
876700) 10C, and a gear body mechanism 10D including a multi-plate clutch that is crimped, released, engaged, and disengaged by hydraulic pressure adjustment by the ECMV valve 10C. In the gear body mechanism 10D, the engine 1
The rotational driving force transmitted from the engine 11 to the input shaft 13 integrally and coaxially connected to the engine output shaft 12 of No. 1 is changed to three forward gears and three reverse gears by switching the gears to output the output shaft. 14 is transmitted. Next, the gear body mechanism 10D will be specifically described.

With respect to the input shaft 13, a single planetary type reverse planetary gear train 20 and a forward planetary gear train 21 are sequentially provided from the left side in the axial direction of the input shaft 13. The reverse planetary gear 20 includes a sun gear 20a that is integral with the input shaft 13 and the sun gear 20a.
20g located on the outer side of the
a planetary gear 20c interposed between a and 20b and meshing with both gears 20a and 20b, and a planetary carrier 20d which is a carrier of the planetary gear 20c and which can be braked by the compression of a reverse hydraulic clutch 22. ing. In addition, the forward planetary gear train 21 similarly has the input shaft 13
An integral sun gear 21a, a ring gear 21b located outside of the sun gear 21a and capable of being braked by a forward hydraulic clutch 23 being connected by crimping, and both gears 21a
a planetary gear 21c which is interposed between a and 21b and meshes with both gears 21a and 21b, and a planetary carrier 21d which is a carrier of the planetary gear 21c and is integrated with a ring gear 20b of the reverse planetary gear train 20. Has been done.

Next, the above-mentioned output shaft 14 is arranged on the extension line of the input shaft 13 and coaxially with the input shaft 13, and the output shaft 14 is provided with each single planetary type from the left side in the drawing. The third speed planetary gear train 24, the second speed planetary gear train 25, and the first speed disk 26 are sequentially provided. This third speed planetary gear train 24
Is a sun gear 24a integrated with the output shaft 14, and a third speed hydraulic clutch 27 located outside the sun gear 24a.
The ring gear 24b capable of being braked by the connection by crimping and the gears 24a, 24b interposed between the gears 24a, 24b.
A planetary gear 24c meshing with 24b and the planetary gear 24
A planet carrier 24 which is a carrier of c and is integrally connected to the planet carrier 21d of the forward planetary gear train 21.
and d. In addition, the second speed planetary gear train 25 is likewise integrated with the output shaft 14 into a sun gear 25a.
And a ring gear 25b located outside of the sun gear 25a and capable of being braked by crimping connection of the second speed hydraulic clutch 28, and an interposition between these gears 25a, 25b to mesh with both gears 25a, 25b. And a planetary carrier 25d which is a carrier of the planetary gear 25c and is integral with the ring gear 24b of the third speed planetary gear train 24. The first speed disc 26 is
The first speed hydraulic clutch 29, which is integrally provided with the ring gear 25b of the second speed planetary gear train 25, can be braked by being joined by pressure bonding, and is provided integrally with the output shaft 14. There is.

Thus, the gear body mechanism 10D described above is
It is housed in a case 30 shown by a chain line in FIG. 1, and a reverse hydraulic clutch 22, a forward hydraulic clutch 23, a third speed hydraulic clutch 27 and a second speed hydraulic oil are stored in the case 30. The clutch 28 is integrally provided. In addition, the reverse hydraulic clutch 22
And the traveling direction clutch of the forward hydraulic clutch 23,
Third speed hydraulic clutch 27, second speed hydraulic clutch 28
Also, as compared with the speed clutch of the first speed hydraulic clutch 29, the load clutch is composed of a multi-layer multi-plate clutch and is excellent in impact resistance, wear resistance, heat resistance and the like.

Subsequently, the transmission 1 having the above structure
At 0, the operator operates the speed lever 10A to adjust the hydraulic pressure by the ECMV valve 10C via the controller 10B to individually crimp, release, engage, and disengage the clutches 22, 23, 27 to 29 to move forward and backward and speed steps. The shift control characteristic will be described.
In addition, here, the forward first speed (F1) to the forward second speed (F2)
2 and FIG. 3 will be specifically described with respect to the case of shifting in the same traveling direction and the case of shifting in the reverse traveling direction from the second forward speed (F2) to the first reverse speed (R1).

(I) First forward speed (F1) to second forward speed (F)
2) When shifting gears in the same traveling direction (see FIG. 2) In the first forward speed state, the forward hydraulic clutch 23 and the first speed hydraulic clutch 29 are completely crimped and joined together, and the reverse hydraulic clutch 22 is also used. , The third speed hydraulic clutch 27 and the second speed hydraulic clutch 28 are completely released and disconnected. The rotational driving force transmitted to the input shaft 13 via the engine output shaft 12 of the engine 11 in this case is the forward planetary gear train 21 as shown in FIG.
Sun gear 21a, planetary gear 21c, planetary carrier 24d of the planetary gear train 24 for the third speed, planetary gear 24c, ring gear 24b, planetary carrier 25 of the planetary gear train 25 for the second speed.
d, the planetary gear 25c, the ring gear 25b, and the first speed disk 26 are sequentially transmitted to the output shaft 14.

In this first forward speed state, when the operator operates the speed lever 10A to switch from the first forward speed to the second forward speed, shift control is performed as follows. First, the hydraulic pressure 29 for the first speed on the disengagement side is released and disengaged while the hydraulic pressure is released to a semi-engaged state in which a static torque transmission force of about 100% that causes slippage in response to an impact, and the second side on the engaged side. The hydraulic pressure for speed 28 is increased to a semi-engaged state in which the static torque transmission force is about 60%, and the hydraulic clutch 28 is crimped and engaged.

Next, the hydraulic pressure of the forward hydraulic clutch 23 is lowered to a semi-engaged state where the static torque transmission force is about 40%, released and disconnected, and the hydraulic pressure of the first speed hydraulic clutch 29 in the semi-engaged state is changed. It is further lowered and completely released and cut. Subsequently, the hydraulic pressures of the semi-engaged second speed hydraulic clutch 28 having a static torque transmission force of about 60% and the semi-engaged forward hydraulic clutch 23 of a static torque transmission force of about 40% are used for the second speed. The hydraulic clutch 28 is prioritized in comparison with the forward hydraulic clutch 23 so that the hydraulic clutch 28 is gradually and completely coupled to gradually increase the static torque transmission force of about 200%, which does not cause slippage against impact. And crimped.

According to such shift control of the speed stage,
The torque is not cut off during the shift, the decrease in the vehicle speed due to the torque cut is suppressed, the shock is eliminated, and the riding comfort is improved.

In this way, the forward speed is changed from the first forward speed to the second forward speed.
The rotational driving force transmitted to the input shaft 13 through the engine output shaft 12 of the sun gear 21a, the planetary gear 21c, and the third speed planetary gear 21 of the forward planetary gear train 21 are as shown in FIG. Planet carrier 24d, planet gears 24 in row 24
c, the ring gear 24b, the planetary carrier 25d of the second speed planetary gear train 25, the planetary gear 25c, and the sun gear 25a are sequentially transmitted to the output shaft 14.

(Ii) 2nd forward speed (F2) to 1st reverse speed (R
1) When shifting gears in the reverse traveling direction (see FIG. 3) In the above-described second forward speed state, the operator operates the speed lever 1
When 0A is operated to switch from the second forward speed to the first reverse speed, shift control is performed as follows. First, the hydraulic pressure 28 for the second speed on the disengagement side is released and disengaged while the hydraulic pressure is released to a semi-engaged state in which a static torque transmission force of about 100% that causes slippage with respect to impact, and is disengaged. The hydraulic clutch for speed 29 is hydraulically increased to a semi-engaged state in which the static torque transmission force is about 60%, and is crimped and engaged.

Next, the hydraulic pressure 23 for advancing on the disengagement side is reduced until the hydraulic clutch 23 is completely released and disengaged, and the hydraulic pressure for the second speed hydraulic clutch 28 in the semi-engaged state is further reduced and completely released. And then disconnected. Next, the hydraulic pressure between the first-speed hydraulic clutch 29 in the semi-engaged state with a static torque transmission force of about 60% and the reverse hydraulic clutch 22 on the engaging side, particularly the hydraulic pressure of the reverse hydraulic clutch 22, causes torque cutoff. The hydraulic clutch for the first speed 29
Is gradually prioritized in comparison with the reverse hydraulic clutch 22 so that the clutch is gradually and completely coupled, and is gradually raised and crimped to a completely coupled state with a static torque transmission force of about 200% which does not cause slippage even with impact. It

According to such shift control of the speed stage,
Similar to the shift in the same traveling direction described above, the shock is suppressed without the torque being cut off during the shift.

In this way, the second forward speed is changed to the first reverse speed, and in the reverse first speed state, the engine 11
The rotational driving force transmitted to the input shaft 13 via the engine output shaft 12 of the sun gear 20a, the planetary gear 20c, the ring gear 20b, and the forward gear 20b of the reverse planetary gear train 20 as shown in FIG. The planet carrier 21d of the planetary gear train 21,
The planet carrier 24d of the third speed planetary gear train 24, the planetary gear 24c, the ring gear 24b, the planet carrier 25d of the second speed planetary gear train 25, the planetary gear 25c, the ring gear 25b, and the first speed disk 26 are sequentially arranged. Is transmitted to the output shaft 14.

Finally, as another embodiment, the speed clutches of the third speed hydraulic clutch 27, the second speed hydraulic clutch 28 and the first speed hydraulic clutch 29 are the reverse speed hydraulic clutch 22 and the forward speed hydraulic clutch 23. A case will be described in which, as compared with the traveling direction clutch, the load clutch is configured by a multi-layered multi-plate clutch and is excellent in impact resistance, wear resistance, heat resistance, and the like. Other than that, the structure is the same as that of the above-described embodiment, and the description of the same parts as those of the above-mentioned embodiment will be omitted and only different parts will be described.

Similar to the above-described embodiment, the forward movement based on the clutches 22, 23, 27 to 29 which are individually crimped, released, engaged and disengaged by hydraulic pressure adjustment based on the operation of the speed lever 10A by the operator in the transmission 10. When shifting from the first speed (F1) to the second forward speed (F2) in the same traveling direction, and when shifting from the second forward speed (F2) to the first reverse speed (R1)
The shift control characteristics in the case of shifting in the reverse traveling direction will be specifically described with reference to FIGS. 7 and 8.

(I) First forward speed (F1) to second forward speed (F)
2) When shifting gears in the same traveling direction (see FIG. 7) First, the forward hydraulic clutch 23 sets the static torque transmission force to 100.
%, The hydraulic pressure is lowered to a semi-engaged state, released and disconnected, and the second speed hydraulic clutch 28 on the engagement side is hydraulically increased to a semi-engaged state with a static torque transmission force of about 60% to be crimped and engaged. To be done.

Next, the disengagement side first speed hydraulic clutch 29.
The hydraulic pressure is reduced until the is completely released and disconnected. Subsequently, the hydraulic pressures of the forward hydraulic clutch 23 in the semi-engaged state with a static torque transmission force of about 100% and the second-speed hydraulic clutch 28 in the semi-engaged state with a static torque transmission force of about 60% change. Is preferentially compared with the hydraulic clutch 28 for the second speed, and is gradually and completely engaged so that the static torque transmission force of about 200% is gradually raised and crimped.

(Ii) From the second forward speed (F2) to the first reverse speed (R
1) In the case of shifting in the reverse traveling direction (see FIG. 8) First, the hydraulic pressure of the disengagement side forward hydraulic clutch 23 is reduced to a semi-engaged state with a static torque transmission force of about 100%, released, and disconnected. The hydraulic pressure for the first-speed hydraulic clutch 29 on the coupling side is increased to a semi-engaged state in which the static torque transmission force is about 60%, and is pressed and engaged.

Next, the disconnection side second speed hydraulic clutch 28 is provided.
Is lowered until it is completely released and disconnected, and the hydraulic pressure of the forward hydraulic clutch 23 in the semi-engaged state is further lowered to be completely released and disconnected. Then, the reverse hydraulic clutch 22 on the coupling side and the static torque transmission force 60
The hydraulic pressure of the first-speed hydraulic clutch 29 in a semi-engaged state of about 10% is increased so that the hydraulic pressure of the reverse-direction hydraulic clutch 22 does not cause torque cutoff, and the reverse-direction hydraulic clutch 22 is changed to the first-speed hydraulic clutch 29. And the reverse hydraulic clutch 22 and the first speed hydraulic clutch 29 have a static torque transmission force of 200%.
It is gradually raised to a completely bonded state and crimped.
Others are the same as the case of the above-mentioned embodiment.

In the above-mentioned two embodiments, the shift control in which the forward speed is changed from the first forward speed to the second forward speed, and the forward second speed is changed to the reverse first speed, the first forward speed, the second forward speed, and the third forward speed are described. The same applies to shift control of gear shift between any two of the reverse first speed, the reverse second speed, and the reverse third speed.

Although the above-described two embodiments have been described with reference to a transmission having three forward gears and three reverse gears, the shift control method for a vehicle according to the present invention is a transmission having two or more forward gears and two or more reverse gears. It goes without saying that it can be applied.

In the above-mentioned two embodiments, the former case is the case where the traveling direction clutch is the load clutch, and the latter case is the case where the speed clutch is the load clutch. However, these traveling direction clutch and speed clutch have the same impact resistance. sex,
It is needless to say that the vehicle shift control method according to the present invention can be applied even when it has wear resistance and heat resistance.

In the above-described two embodiments, when shifting in the reverse traveling direction of the former, as shown in FIG. 3, the first speed hydraulic clutch 29 is in a semi-engaged state with a static torque transmission force of about 60%. Is rapidly engaged until the forward hydraulic clutch 23 and the second speed hydraulic clutch 28 are completely disengaged, and then the reverse hydraulic clutch 22 has a static torque transmission force of 60%.
The hydraulic clutch 29 for the first speed is gradually connected to a semi-engaged state with a static torque transmission force of about 60% as shown in FIG. Before the hydraulic clutch 23 and the second speed hydraulic clutch 28 are completely disengaged, the reverse speed hydraulic clutch 22 may be gradually coupled together with the first speed hydraulic clutch 29. Further, in the latter case of shifting in the reverse traveling direction, as shown in FIG. 8, the reverse hydraulic clutch 22 abruptly reaches a semi-engaged state with a static torque transmission force of about 80%, and the hydraulic pressure for the first speed is also increased. The clutch 29 was rapidly engaged into a semi-engaged state with a static torque transmission force of about 60%.
As shown in FIG. 10, the reverse hydraulic clutch 22
May be gradually connected to a semi-engaged state in which the static torque transmission force is about 80%, and the first speed hydraulic clutch 29 may be gradually connected. Others are the same as the above-mentioned embodiment.

As described above, it is obvious that the present invention can be modified in various ways. All such modifications are within the spirit and scope of the present invention and all such variations and modifications apparent to those skilled in the art are intended to be within the scope of the following claims.

[0042]

As described above, according to the present invention, since the torque is not cut off during the shift, at least no shock is generated and the ride comfort is good.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a vehicle transmission for explaining a specific embodiment of a vehicle shift control method according to the first invention.

FIG. 2 is a shift control characteristic diagram from the first speed to the second speed in the same traveling direction of the vehicle for explaining a specific embodiment of the vehicle shift control method according to the first aspect of the present invention.

FIG. 3 is a second view in the reverse traveling direction of the vehicle for explaining a specific embodiment of the vehicle shift control method according to the first aspect of the present invention.
Shift control characteristic diagram from first speed to first speed

FIG. 4 is an explanatory diagram showing a power transmission state in a first forward speed state used in the description of FIG. 2;

FIG. 5 is an explanatory diagram showing a power transmission state in a forward second speed state used in the description of FIG. 2;

6 is an explanatory diagram showing a power transmission state in a reverse first speed state used in the description of FIG. 3;

FIG. 7 is a shift control characteristic from the first speed to the second speed in the same traveling direction of the vehicle corresponding to FIG. 2 for explaining a specific embodiment of the vehicle shift control method according to the second and third inventions. Figure

FIG. 8 is a shift control characteristic from the second speed to the first speed in the reverse traveling direction of the vehicle corresponding to FIG. 3 for explaining a specific example of the vehicle shift control method according to the second and third inventions. Figure

FIG. 9 is a shift control characteristic diagram from the second speed to the first speed as a modified example corresponding to FIG. 3 in the reverse traveling direction of the vehicle.

FIG. 10 is a shift control characteristic diagram from the second speed to the first speed as a modified example corresponding to FIG. 8 in the reverse traveling direction of the vehicle.

[Explanation of Codes] 10 transmission 11 engine 12 engine output shaft 13 input shaft 14 output shaft 20 reverse planetary gear train 21 forward planetary gear train 22 reverse hydraulic clutch 23 forward hydraulic clutch 24 third speed planetary gear train 25 2nd-speed planetary gear train 26 1st-speed disk 27 3rd-speed hydraulic clutch 28 2nd-speed hydraulic clutch 29 1st-speed hydraulic clutch 30 Case

Claims (24)

[Claims] 1. A shift control method for a vehicle for performing forward / backward and speed stage shift control by connecting and disconnecting forward and backward traveling direction clutches and at least first and second speed clutches. a) First on the cutting side
While disconnecting the speed clutch of to the semi-engaged state,
A first step of engaging the second speed clutch on the engaging side to a semi-engaged state; and (b) completely disengaging the first speed clutch in the semi-engaged state and the second speed clutch in the semi-engaged state. A shift control method for a vehicle, comprising a second step of completely combining the above. 2. The semi-engaged state of the first speed clutch is a semi-engaged state in which the static torque transmission force is larger than the semi-engaged state of the second speed clutch. Item 2. A shift control method for a vehicle according to Item 1. 3. When shifting the vehicle in the same traveling direction, in the second step, first, the traveling direction clutch is disengaged to a semi-engaged state, and the first speed clutch in the semi-engaged state is completely disengaged. 2. The vehicle according to claim 1, wherein the semi-engaged second speed clutch is then gradually fully engaged and the semi-engaged advancing clutch is gradually fully engaged again. Shift control method. 4. The semi-engaged state of the first speed clutch,
4. The shift control of the vehicle according to claim 3, wherein the semi-engaged state of the second speed clutch and the semi-engaged state of the traveling direction clutch are semi-engaged states in which the static torque transmission force is sequentially small. Method. 5. When the second speed clutch and the traveling direction clutch are gradually and completely coupled, the second clutch
5. The shift control method for a vehicle according to claim 3, wherein the speed clutch is prioritized as compared with the traveling direction clutch and is gradually and completely coupled. 6. When shifting the vehicle in the reverse traveling direction, in the second step, first, one traveling direction clutch on the disengagement side is completely disengaged, and the first half-engaged state clutch is engaged.
Completely disengaging the first speed clutch, then progressively fully engaging the second speed clutch in the semi-engaged state, and progressively fully engaging the other traveling direction clutch on the coupling side. 2. The vehicle shift control method according to 1. 7. When the second speed clutch and the other traveling direction clutch are gradually and completely engaged, the second speed clutch is prioritized over the traveling direction clutch and gradually and completely engaged. 7. The shift control method for a vehicle according to claim 6, wherein: 8. A shift control method for a vehicle for performing forward / backward and speed stage shift control by connecting and disconnecting forward and reverse traveling direction clutches and at least first and second speed clutches. a) a first step of disconnecting the traveling direction clutch to a semi-engaged state and engaging a second speed clutch on the engaging side to a semi-engaged state; and (b) first completely disconnecting the first speed clutch on the disengaging side. Disengaging, then fully engaging and returning the semi-engaged advancing clutch again, and fully engaging the semi-engaged second speed clutch, including the same advancing direction of the vehicle. A shift control method for a vehicle, characterized in that 9. The semi-engaged state of the traveling direction clutch is
9. The shift control method for a vehicle according to claim 8, wherein the second speed clutch is in a semi-engaged state in which the static torque transmission force is larger than that in the semi-engaged state. 10. In the second step, the semi-engaged traveling direction clutch and the semi-engaged second speed clutch are gradually engaged when completely engaged, and the traveling direction clutch is operated by the second clutch. 10. The shift control method for a vehicle according to claim 9, wherein the speed clutch is prioritized in comparison with the speed clutch and is gradually coupled. 11. The shift control method for a vehicle according to claim 3, wherein the traveling direction clutch is one of a traveling direction clutch for forward movement and a backward movement. . 12. A shift control method for a vehicle for performing forward / backward and speed stage shift control by connecting and disconnecting a forward direction or reverse direction traveling direction clutch and at least a first speed clutch and a second speed clutch. a) The first step of disconnecting one of the traveling direction clutches to the semi-engaged state and engaging the second speed clutch on the engaging side to the semi-engaged state, and (b) the first speed clutch on the disengaging side. Fully disengaged, one of the semi-engaged clutches is completely disengaged, then the other clutch is fully engaged, and the semi-engaged second speed clutch is fully engaged. A shift control method for a vehicle, comprising a second step of performing a shift in the reverse traveling direction of the vehicle. 13. The semi-engaged state of the one traveling direction clutch is a semi-engaged state in which the static torque transmission force is greater than the semi-engaged state of the second speed clutch. Item 13. A shift control method for a vehicle according to item 12. 14. In the second step, the other traveling direction clutch and the second speed clutch in the semi-engaged state are gradually engaged when completely engaged, and the other traveling direction clutch is operated at the second speed. 14. The shift control method for a vehicle according to claim 13, wherein the clutch is prioritized in comparison with the clutch and is gradually coupled. 15. The one-way traveling clutch is a forward traveling traveling clutch, and the other traveling clutch is a backward traveling traveling clutch. A method for controlling a shift of a vehicle according to item 1. 16. The one-way traveling clutch is a backward traveling traveling clutch, and the other traveling clutch is a forward traveling traveling clutch. A method for controlling a shift of a vehicle according to item 1. 17. The first speed clutch is a first speed clutch, and the second speed clutch is a second speed clutch.
15. The vehicle shift control method according to any one of 6 to 10, 12 to 14. 18. The first speed clutch is a second speed clutch, and the second speed clutch is a first speed clutch. 15. The shift control method for a vehicle according to any one of 10, 12 to 14. 19. The shift control method for a vehicle according to claim 1, wherein the traveling direction clutch and the speed clutch are multi-plate clutches that are pressed and released by hydraulic pressure to be engaged and disengaged. . 20. The shift control method for a vehicle according to claim 5, wherein the traveling direction clutch is a load clutch. 21. The shift control method for a vehicle according to claim 10, wherein the speed clutch is a load clutch. 22. The shift control method for a vehicle according to claim 1, wherein the vehicle is a vehicle for a construction machine having two or more speed stages in forward and backward movements. 23. The vehicle according to claim 6, wherein the other traveling direction clutch is gradually engaged after the first speed clutch on the disengagement side is disengaged to a semi-engaged state. Shift control method. 24. The shift control method for a vehicle according to claim 12, wherein the other traveling direction clutch is gradually engaged after the one traveling direction clutch is disengaged to a semi-engaged state.