JP2678631B2 - Hydraulically operated transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is mainly intended for automatic transmission, in which a plurality of transmission systems are selectively established by engagement of respective hydraulic clutches intervening in the respective transmission systems. A hydraulically actuated transmission.

(Prior Art) In this type of transmission, when the vehicle speed is increased by a driver's acceleration operation to shift up, for example, shifting from 2nd speed to 3rd speed is performed, a 2nd speed hydraulic clutch intervening in the 2nd speed transmission system is used. If the third-speed hydraulic clutch, which is intervening in the third-speed transmission system, is engaged after the disengagement, the transmission temporarily becomes in the neutral state and the engine is blown up. Therefore, prior to releasing the second-speed hydraulic clutch. Under the present circumstances, the third speed hydraulic clutch is started to be engaged, and both hydraulic clutches generate a so-called co-engagement state in which both hydraulic clutches have an engaging force to prevent the engine from rising.

By the way, in the intermeshing state, the input shaft and the output shaft of the transmission are connected via the two transmission systems having different reduction ratios, and the rotation of both shafts corresponds to the engaging force of the hydraulic clutches of these transmission systems. Braking force is applied, the driving torque (rotational torque of the driving wheels) is temporarily reduced, and smoothness of shifting is impaired. Therefore, the engaging force of the second speed hydraulic clutch on the releasing side is changed to the engaging force on the engaging side. There is also known one in which the hydraulic pressure of a three-speed hydraulic clutch is rapidly lowered to a predetermined value so as to regulate excessive co-engagement (Japanese Patent Publication No. 48-21369).

However, since the hydraulic pressure required to engage the hydraulic clutch changes depending on the load, if the above-mentioned predetermined value is set low, the third-speed hydraulic clutch is sufficient when shifting up from the second speed to the third speed under high load. If the second speed hydraulic clutch is released before the resultant force is generated to cause the engine to blow up, or if the predetermined value is set to a high value, the release of the second speed hydraulic clutch will be delayed when shifting up at low and medium loads Cause chewing,
The driving torque is greatly reduced, and it is difficult to perform proper co-engagement over all of various shift conditions.

Considering a case where the driver strongly depresses the accelerator pedal to shift down from the 3rd speed to the 2nd speed, in this case, the 3rd speed hydraulic clutch is released early to temporarily shift the neutral position during the shifting process. When a state is created and the engine is slightly blown up, the difference in rotational speed between the input side and the output side of the second speed hydraulic clutch is reduced, the second speed hydraulic clutch is smoothly engaged, and the shift shock is reduced. .

However, if the neutral state is too long, the engine speed will increase more than necessary, so the engine speed will increase 2 times sooner than when the difference in speed between the input side and the output side of the 2-speed hydraulic clutch disappears.
The current situation is to control the oil supply / drainage to the 2nd and 3rd speed hydraulic clutches so that the 2nd speed hydraulic clutch is engaged. Is forcibly raised from a state where it is lower than the rotation speed on the output side until it becomes equal to this, and the pull-up load of rotation of all rotary members from the output side of the second speed hydraulic clutch to the engine is increased. Due to this load, the drive torque is temporarily reduced significantly and the smoothness of gear shifting is impaired.

Further, conventionally, there is known a transmission in which a one-way clutch that allows over-rotation on the output side is intervened in a first-speed transmission system. In such a transmission, a first-speed hydraulic clutch is used when shifting up from the first speed to the second speed. Even when the clutch is engaged, the second speed hydraulic clutch begins to have an engaging force and the rotation speed of the input shaft begins to decrease. At the same time, the one-way clutch works to automatically transmit power through the first speed transmission system. The first speed and the second speed transmission systems are not established at the same time during the shifting process, that is, co-engagement does not occur, and smooth gear shifting is performed without a decrease in drive torque due to co-engagement. Even when shifting down to the 1st speed, the engine speed up due to the release of the 2nd speed hydraulic clutch increases the rotation speed on the input side of the one-way clutch, and when the speed is about to exceed the rotation speed on the output side. Way clutch is engaged to 1
A high speed transmission system is established, and the output side of the transmission does not bear a load for increasing the rotation of the input side, and smooth gear shifting is performed.

(Problems to be Solved by the Invention) By interposing the one-way clutch in the transmission system as described above, it is possible to prevent a decrease in the drive torque during the gear shifting process and to achieve smooth gear shifting. The intervening transmission system cannot transmit the reverse drive torque from the drive wheels, and there is a problem that the engine brake does not work.
It is not possible to intervene a one-way clutch in a high speed transmission system.

In this case, the transmission system of the second speed or the third speed is provided with an engagement element capable of directly connecting the input side and the output side of the one-way clutch in parallel with the one-way clutch, and is intended for engine braking such as opening the throttle to an extremely low opening. It is conceivable that when the operation is performed, the engaging element is operated so that the reverse drive torque can be transmitted from the output side of the one-way clutch to the input side. There are many inconveniences such as an increase in size, an increase in weight, and a complicated hydraulic control device.

By the way, as a multi-disc clutch used for a main clutch interposed between an engine and a transmission of a motorcycle, according to Japanese Patent Publication No. 51-31893, a clutch outer connected to the engine is provided with a plurality of clutch plates. The clutch inner to be engaged is divided into at least two, and one first inner is directly connected to the input shaft of the transmission, and the other second inner is connected via a one-way clutch that allows over-rotation on the input shaft side. Those connected to the shaft are known. In this case, when a reverse load acts on the input shaft due to downshifting of the transmission, the second inner does not transmit the reverse load due to the action of the one-way clutch, so the reverse load is transmitted only through the first inner. Since the engaging force of the first inner is half of the engaging force of the entire clutch, slippage of the first inner with respect to the clutch outer occurs, and the reverse load is absorbed by the slip, which is caused by the reverse load. It prevents the chain from being cut and the transmission gear from being damaged.

The present invention utilizes the technology of such a multi-plate clutch, and is a hydraulically actuated type that is capable of performing smooth gear shifts without causing the above-mentioned problems in the one-way clutch and a parallel engagement element used in combination therewith. The purpose is to provide a transmission.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the present invention is a hydraulically actuated type in which a plurality of transmission systems are selectively established by engagement of respective hydraulic clutches intervening in the respective transmission systems. In a transmission, a hydraulic clutch that is intervened in all or part of a transmission system is configured to include at least two clutch inners, that is, a first clutch clutch and a second clutch inner that are connected to the clutch outer in parallel. ,
The first clutch inner is directly connected to a member on the input side or the output side of the hydraulic clutch, and the second clutch inner is connected to the member via a one-way clutch, and the member is an input-side member by the one-way clutch. In this case, the second clutch inner side is allowed, and when the member is an output side member, over-rotation of the member side is allowed.

In this case, in order to install the one-way clutch compactly in the hydraulic clutch, one of the clutch inners has a relatively large-diameter cylindrical portion and the other has a relatively small-diameter cylindrical portion that is inserted into the cylindrical portion. It is desirable that the one-way clutch is formed between the two cylinder parts.

(Operation) Regarding the action during upshifting of 2nd → 3rd speed and downshifting of 3rd → 2nd speed when the 2nd speed hydraulic clutch intervening in the 2nd speed transmission system has two clutch inners explain.

In the second speed hydraulic clutch, the clutch outer is coupled to the input side member, the first clutch inner is directly coupled to the output side member, and the second clutch inner is rotated to the output side member. Shall be connected via a one-way clutch that allows

When shifting up from the 2nd speed to the 3rd speed, as described in the section of the prior art above, the 3rd speed is applied before the 2nd speed hydraulic clutch is released.
The quick hydraulic clutch is started to engage so as to cause the intermeshing state and prevent the engine from rising.

In this case, the engagement of the third speed hydraulic clutch is started, the input side rotational speed of the second speed hydraulic clutch decreases, and at the same time, the one-way clutch is disengaged, and the second speed transmission system uses only the engaging force of the first clutch inner. Will be established and maintained,
The engaging force of the second speed hydraulic clutch is substantially halved, and the slip of the clutch rapidly increases.

Therefore, the braking phenomenon due to the co-engagement is largely suppressed, and the decrease in the drive torque during the gear shifting process is reduced,
Smooth shift up is performed.

Further, when shifting down from the third speed to the second speed, the second speed hydraulic clutch is started to be engaged before the input speed becomes equal to the output speed after releasing the third speed hydraulic clutch as in the conventional case. In this case, the one-way clutch is not engaged from the start of engagement until the input speed is increased to the output speed, during which the engagement force of the second speed hydraulic clutch is restricted to the engagement force of only the first clutch inner. The second-speed hydraulic clutch easily slips, and this slip reduces the load on the output side to increase the rotation of the input side, prevents a drastic decrease in the drive torque, and reduces the rotational speed of the input side to that of the output side. The one-way clutch is engaged when the rotation speed is increased, the engaging force of the second speed hydraulic clutch is increased, and the required torque transmission required for acceleration is performed, resulting in a smoother downshift than in the prior art. Towards To.

Note that the reverse drive torque is transmitted only by the engagement force of the first clutch inner during engine braking, but the engagement force of the hydraulic clutch in the completed engagement state transmits sufficient torque even at the maximum torque output of the engine. Since the reverse drive torque is much smaller than the maximum torque of the engine, there is enough engagement force to transmit the reverse drive torque even if the engagement force of the hydraulic clutch is halved. It doesn't get worse.

Further, in both cases of shifting up from the second speed to the third speed and shifting down from the third speed to the second speed, it is effective to secure smoothness of the shifting that the second speed transmission system on the low speed side is effective as described above. It is meaningless to secure smoothness of shifting even if the transmission speed hydraulic clutch of the highest speed stage is configured with a one-way clutch such as the above-mentioned second speed hydraulic clutch. is there.

However, if the operation is performed such that the select lever of the transmission is once switched to the neutral range and then switched to the automatic transmission range during high-speed traveling, the hydraulic clutch of the transmission system of the highest speed stage is refueled at this point of operation. If this operation is performed with the accelerator pedal released and the engine speed reduced, the output side bears the load of increasing the input side rotation when the hydraulic clutch is engaged. In order to mitigate the sudden fluctuation of the driving torque and reduce the shock, the transmission system hydraulic clutch at the highest speed stage may be configured with a one-way clutch.

Further, when the hydraulic clutch is provided so that the clutch outer is connected to the output side member, the first clutch inner is directly connected to the input side member and the second clutch inner is over-rotated by the second clutch inner. The one-way clutch is not engaged while the input side member is connected to the input side member via a one-way clutch that allows the rotation speed of the input side member to be lower than the rotation speed of the second clutch inner located on the output side with respect to the input side member. In this way, the same effect as above can be obtained.

(Embodiment) Referring to FIG. 1, (1) shows a transmission connected to a crankshaft (2) of an engine through a fluid torque converter (3), and the transmission (1) is a transmission. In the case (4), an input shaft (5) connected to the fluid torque converter (3) and an output shaft (7) connected to an output gear (6) connected to the drive wheels of the vehicle are axially supported in parallel. It is constructed in a two-axis parallel type, and transmission systems G1, G2, G3, G4 for the first to fourth speeds for forward movement and a reverse transmission system GR are arranged in parallel between the two shafts (5) and (7). 1 to 4 for each transmission system G1, G2, G3, G4 for forward movement
Forward 4 by engaging each hydraulic clutch C1, C2, C3, C4
A hydraulically actuated transmission that shifts one speed in reverse is constructed.

More specifically, the first speed transmission system G1 includes a first speed hydraulic clutch C1 on the input shaft (5), a drive gear G1a connected to the first speed hydraulic clutch C1, and a driven gear G1b that meshes with the gear G1a. It consists of a fixed parking gear G1c on the output shaft (7),
A one-way clutch (8) that allows over-rotation of the parking gear G1c on the output side is interposed between the driven gear G1b and the parking gear G1c, and the one-way clutch (8) is used as described in the section of the prior art. By the action of 8), it is possible to smoothly perform upshifting from 1st gear and downshifting to 1st gear.

The 2-speed transmission system G2 is a 2-speed hydraulic clutch on the input shaft (5).
C2, a drive gear G2a connected thereto, and a driven gear G2b fixed to the output shaft (7) that meshes with the gear G2a, and the three-speed transmission system G3 includes an input shaft (5 ) Integrally formed with the drive gear G3a, and a driven gear G3b that meshes with this,
3rd speed hydraulic clutch C3 on the output shaft (7) connected to this
And the four-speed transmission system G4 includes a four-speed hydraulic clutch C4 on the input shaft (5), a drive gear G4a connected to the four-speed hydraulic clutch C4, and a driven gear G4b meshing with the gear G4a. In addition, a drive gear GRa of the reverse transmission system GR is formed integrally with the drive gear G4a, and the driven gear of the reverse transmission system GR is engaged with the gear GRa via an idle gear (not shown).
In the drawing of the selector gear (9) on the output shaft (7), the GRb and the driven gear G4b of the fourth speed transmission system are selectively switched by the switching operation between the right reverse position and the left forward position (position shown). The reverse transmission system GR is established by connecting the output gear (7) to the output shaft (7), switching the selector gear (9) to the reverse position and supplying oil to the fourth speed hydraulic clutch C4.

In the figure, (10) shows an oil pump provided at the engine-side end of the transmission case (4), and (11) shows a valve block incorporating various valves such as a manual valve and a shift valve. When the vehicle is traveling forward by switching to the automatic shift range by the select lever in the room, first, the pressure oil from the pump (10) is inserted into the input shaft (5) planted in the end wall of the case (4). When the 1st speed transmission system G1 is established by supplying oil to the 1st speed hydraulic clutch C1 via (12 ₁ ) and then the running state enters the 2nd speed range, the oil hole (12 ₂ ) formed in the input shaft (5) When the second speed hydraulic system C2 is established by supplying oil to the second speed hydraulic clutch C2 via the, and then the vehicle speed further increases to enter the third speed range, the oil discharged from the second speed hydraulic clutch C2 and the case (4 ₃ ) via a pipe (12 ₃ ) inserted into the output shaft (7) planted in the end wall of When oil is supplied to the high-speed hydraulic clutch C3 to establish the third-speed transmission system G3 and the vehicle speed further increases to enter the fourth-speed region, the oil discharged from the third-speed hydraulic clutch C3 and the case (4) The oil is supplied to the fourth speed hydraulic clutch C4 through the pipe (12 ₄ ) inside the pipe (12 ₁ ) inserted into the input shaft (5) planted in the end wall of the fourth speed transmission system. G4 has been established. During this forward traveling, the selector gear (9) is in the forward traveling position, and the first speed hydraulic clutch C1 is constantly refueled and held in the engaged state.

Here, the second and third speed hydraulic clutches C2 and C3 are divided into first and second second clutches which are respectively engaged in parallel with the clutch outers C2a and C3a via two clutch plates C2b and C3b, respectively. It is assumed that each clutch inner C2c, C2d, C3c, C3d is provided, and the first clutch inner C2c of the second speed hydraulic clutch C2 is
The second clutch inner C2d is directly connected to the drive gear G2a of the second speed transmission system G2, which is a member on the output side of 2, and the one-way clutch (13 ₁ ) for allowing the gear G2a to over-rotate. Connected and the first of the 3rd speed hydraulic clutch C3
The clutch inner C3c is directly connected to the driven gear G3b of the third speed transmission system G3 which is a member on the input side of the clutch C3, and the second clutch inner C3d of the one-way clutch which allows the gear G3b to overrotate the inner C3d ( 13 ₂ ).

In the figure, the hydraulic clutches C for the 2nd and 3rd speeds are shown.
The first and second clutch inners C2c, C3c of 2, C3 are provided with the respective gears G2a, G3.
A relatively large-diameter cylinder portion C2e, C3e integral with b and a relatively small-diameter cylinder portion C2f, C3f housed in the cylinder portion C2e, C3e are formed in the second clutch inners C2d, C3d to form a second speed. Between the two cylinder parts C2e, C2f of the hydraulic clutch C2 and the both cylinder parts C3e, C3f of the third speed hydraulic clutch C3.
The one-way clutches (13 ₁ ) and (13 ₂ ) are interposed between the hydraulic clutches C2 and C3 so that they can be made as compact as possible.

In the figure, (14) shows a lock-up latch built in the fluid torque converter (3).

 Next, the operation of the present embodiment will be described.

At time t ₁ in FIG. 2, the oil discharged from the third speed hydraulic clutch C3 and
Start the oil supply to speed hydraulic clutch C2, in considering the case of a downshift of 3rd speed → 2 speed, as shown in this case FIG. 2 (c), the hydraulic pressure P ₃ of the third speed hydraulic clutch C3 is relatively rapidly decreases, but the third speed hydraulic clutch C3 at time t ₂ is substantially released, the hydraulic pressure P ₂ of the second speed hydraulic clutch C2 is to relatively slowly increase, the second speed hydraulic clutch C2 time t ₃ becomes later than time t ₂ begin to engagement is therefore t ₂ and t ₃
During this period, the transmission (1) is in the neutral state and the engine is blown up so that the input shaft (5) is moved as shown in FIG. 2 (a).
The engine speed starts to increase, while the power from the engine is no longer transmitted to the output shaft (7), so that the drive torque begins to decrease toward zero as shown in FIG. 2 (b).

Here, the number of revolutions of the output shaft (7) during downshift is N, and the number of revolutions of the input shaft (5) before and after downshift is respectively
N ₃ , N ₂ , the reduction ratio of 3rd speed transmission system G 3 and 2nd speed transmission system G 2 respectively
If r ₃ and r ₂ (r ₃ <r ₂ ), Therefore, unless the rotation speed of the input shaft (5) rises to this N ₂ , the rotation speeds of the input side and the output side of the second speed hydraulic clutch C2 do not match.

As of the t _3, the rotation speed of the input shaft (5) is not increased to N _2, the output shaft (7) input via the side is the second speed hydraulic clutch C2 shaft (5) rotation speed of the side N _The load will be increased to ₂ and the drive torque will decrease by that amount to a negative value. During this time, the drive gear G2a on the output side from the second clutch inner C2d on the input side of the one-way clutch (13 ₁ ) , The one-way clutch (13 ₁ ) is not engaged, and the engaging force of the second speed hydraulic clutch C2 is halved to the engaging force of only the first clutch inner C2c, and thus the output shaft (7) side The load to be reduced is reduced and the second speed hydraulic clutch C2
When the engaging force of is not halved, the driving torque is shown in Fig. 2 (b).
In contrast, as shown by the phantom line, the decrease in drive torque is suppressed as shown by the solid line in the figure.

Then, as the rotation speed on the input shaft (5) side increases, the drive torque increases toward zero, and at the time point t ₄ when this rotation speed rises to N ₂ , the one-way clutch (13 ₁ )
Is engaged, and thereafter the engaging force of the second speed hydraulic clutch C2 rapidly increases to the sum of the engaging forces of the first and second clutch inners C2c, C2d, and the drive torque is the value obtained by the second speed transmission system G2. Increase rapidly.

Also, when shifting up from the 2nd speed to the 3rd speed, the hydraulic pressure of the 2nd speed hydraulic clutch C2 is lowered relatively slowly so that the 2nd speed hydraulic clutch C2 is released after the 3rd speed hydraulic clutch C3 starts to engage. Then, the intermeshing state is temporarily generated. In this case, when the rotation speed of the input shaft (5) begins to decrease due to the engagement start of the third speed hydraulic clutch C3, the input side of the _one- way clutch (13 ₁ ) The rotation speed of the second clutch inner C2d becomes lower than the rotation speed of the drive gear G2a on the output side, and the one-way clutch (13 ₁ ) is immediately disengaged, so that the engagement force of the second speed hydraulic clutch C2 is changed to the first clutch inner. The clutch C2 becomes slippery by being halved to the engaging force of only C2c, and this slip suppresses the braking phenomenon of the input / output shafts (5) and (7) due to co-engagement, and the engine blow-up and driving torque are greatly reduced. Smooth shift without causing Toup is done.

Also, when shifting up from 3rd speed to 4th speed or downshifting from 4th speed to 3rd speed, the one-way clutch (13 ₂ ) intervening between the second clutch inner C3d of the third speed hydraulic clutch C3 and the driven gear G3b is used. It functions similarly to the one-way clutch (13 ₁ ) above, and the engagement force of the 3rd speed hydraulic clutch C3 is only the first clutch inner C3c at the time of co-engagement at the time of upshifting and at the time of pulling up the rotation of the input shaft (5) side at the time of downshifting. The engaging force is reduced to half, and smooth gear shifting is performed similarly to the gear shifting of the second speed and the third speed.

If you release the accelerator pedal and apply the engine brake when running in 2nd or 3rd speed, the one-way clutch (13
₁ ) (13 ₂ ) is disengaged and the engaging force of each of the hydraulic clutches C2 and C3 of the 2nd speed and the 3rd speed is halved. However, these hydraulic clutches C2 and C3 are the hydraulic clutch C1 of the 1st speed and the 4th speed. , Like C4,
It is designed so that the engagement force that can sufficiently transmit the maximum output torque of the engine can be obtained in the engagement completed state where the hydraulic pressure has risen to the predetermined hydraulic pressure. Since the torque is much smaller than the torque, the effectiveness of the engine brake is not deteriorated even if the engaging force is halved.

Also, by switching the select lever from the neutral range to the running range such as the automatic shift range while the accelerator pedal is released during running, the second speed hydraulic clutch C2 and the third speed hydraulic clutch C3 are engaged at this switching time. , The output side of each of the hydraulic clutches C2 and C3 bears the load to increase the rotation of the input side, but by the action of the one-way clutch (13 ₁ ) (13 ₂ ) incorporated in each of the hydraulic clutches C2 and C3. The slippage in the engagement process of the hydraulic clutches C2 and C3 becomes large, and the sudden fluctuation of the drive torque due to the rotation pulling load is alleviated, and the shock is alleviated.

In order to obtain the shock reducing action in the switching operation from the neutral range even when the fourth speed hydraulic clutch C4 is engaged at the time of switching, the fourth speed hydraulic clutch C4 is the same as the second speed hydraulic clutch C2. The one with a one-way clutch can be configured.

(Effects of the Invention) As described above, according to the invention of claim 1, by simply changing the structure of the hydraulic clutch, it is possible to perform smooth gear shifting while taking advantage of the one-way clutch without impairing engine braking performance. In addition, the shock that occurs when the select lever is switched from the neutral range to the running range while the accelerator pedal is returned during running can be reduced, and without changing the transmission and its hydraulic control system significantly, high performance is achieved. According to the second aspect of the present invention, the hydraulic clutch with the one-way clutch can be made compact, and the transmission can be prevented from increasing in size.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of an example of a transmission of the present invention, FIG. 2 (a)
(B) and (c) show the characteristics of change in the rotational speed of the input shaft and the characteristics of change in the drive torque during downshifting from the third speed to the second speed, respectively.
FIG. 7 is a diagram showing the change characteristics of the hydraulic pressures of the hydraulic clutches of the first speed and the second speed. G1, G2, G3, G4 …… Transmission system C1, C2, C3, C4 …… Hydraulic clutch C2a, C3a …… Clutch outer C2c, C3c …… First clutch inner C2d, C3d …… Second clutch inner C2e, C3e …… Large diameter cylinder C2f, C3f …… Small diameter cylinder G2a …… Drive gear for 2nd speed transmission system (output side member) G3b …… Drive gear for 3rd speed transmission system (input side member) (13) ₁ ) (13 ₂ ) …… One-way clutch

Claims (2)

(57) [Claims] 1. A hydraulically actuated transmission in which a plurality of transmission systems are selectively established by engagement of respective hydraulic clutches intervening in the respective transmission systems, and all or a part of the transmission systems are intervened. The hydraulic clutch is configured to include at least two first and second clutch inners that are divided so as to be engaged in parallel with the clutch outer, and the first clutch inner is used as an input side or an output side of the hydraulic clutch. And a second clutch inner is connected to the member via a one-way clutch, and when the member is an input-side member by the one-way clutch, the second clutch inner side and the member are output side. The hydraulically actuated transmission is characterized in that when the member is a member, the over-rotation on the member side is allowed. 2. A relatively large-diameter tubular portion is integrally formed on one of the two clutch inners, and a relatively small-diameter tubular portion is inserted into the other tubular inner portion, and the tubular portion is formed between the two tubular portions. The hydraulically actuated transmission according to claim 1, further comprising a one-way clutch.