JP2833238B2 - Wet multi-plate fastening device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet multi-plate fastening device such as a wet multi-plate clutch and a wet multi-plate brake used in an automatic transmission.

[0002]

2. Description of the Related Art A conventional wet multi-plate fastening device is disclosed, for example, in Japanese Patent Application Laid-Open No. 60-263731. FIG. 14 is a sectional view showing the structure of a multiple disc clutch as such a wet multiple disc fastening device.

In FIG. 14, reference numeral 1 denotes a driven plate,
It engages with the inner periphery of the substantially cylindrical clutch drum 2 and rotates integrally with the clutch drum 2. Reference numeral 3 denotes a retaining plate which has a larger axial dimension than the driven plate 1 and has a snap ring 4 provided on the clutch drum 2.
The movement to the right in the figure is prohibited.

A drive plate 5 is engaged with the outer periphery of a substantially cylindrical clutch hub 6 having a smaller diameter than the clutch drum 2, and rotates integrally with the clutch hub 6.

As described above, the driven plate 1, the clutch drum 2, the retaining plate 3, the drive plate 5,
The clutch hub 6 is arranged coaxially, and the driven plate 1, the retaining plate 3, and the drive plate 5 are alternately arranged.

Reference numeral 7 denotes a clutch piston, which is urged to an initial position shown in FIG. 1 by a return spring 8, but when hydraulic oil is supplied to a pressure chamber 9 formed between the clutch piston 2 and the clutch drum 2. The clutch piston 7 is displaced to the driven plate 1 side.

The operation of the multi-plate clutch constructed as described above will be described. When the hydraulic oil is not supplied to the pressure chamber 9, the clutch piston 7 does not move toward the driven plate 1, and the driven plate 1 and the drive plate 5 are not pressed against each other. Therefore, no torque is transmitted between the clutch drum 2 and the clutch hub 6, and the multi-plate clutch is in a non-engaged state.

When hydraulic oil is supplied to the pressure chamber 9, the clutch piston 7 is displaced toward the driven plate 1, and presses the driven plate 1 and the drive plate 5 against the retaining plate 3. Therefore, the clutch drum 2
The transmission of torque is performed between the clutch and the clutch hub 6, and the multi-plate clutch is brought into the engaged state.

[0009]

However, when the conventional wet multi-plate fastening device is not fastened, lubricating oil is interposed between the driven plate 1 and the drive plate 5, and the lubricating oil is Thus, a drag torque (dragging) can be generated due to the viscosity of the liquid crystal. Although the magnitude of the drag torque increases as the clearance C between the driven plate 1 and the drive plate 5 decreases as shown in FIG. 15, especially when the clearance C becomes equal to or less than C0, the drag torque increases significantly. Therefore, it is effective to make the clearance C larger than C0 in order to reduce the drag torque.

However, if the clearance C is set large, the stroke of the clutch piston 7 when the driven plate 1 and the drive plate 5 are pressed against each other increases,
Since the time required for the wet multi-plate fastening device to change from the non-fastened state to the fastened state is lengthened, the time lag (select lag) from the time the shift lever is operated to the time the wet multi-plate fastening device is engaged is increased. There was a problem.

An object of the present invention is to provide a wet-type multi-plate fastening device that can reduce select lugs even when the clearance between plates is set large to reduce drag torque.

[0012]

Means for Solving the Problems To solve the above problems,
According to the first aspect of the present invention, a plurality of first plates that rotate integrally with the first transmission member by being engaged therewith are arranged coaxially with the first transmission member and alternately with the first plates. A plurality of second plates engaged with a second transmission member and integrally rotated, a piston member for pressing a plate group including the plurality of first plates and the plurality of second plates, and a piston The primary fastening plate group adjacent to the member and the secondary fastening plate group separated from the piston member are bisected in the axial direction, and are engaged with the first transmission member or the second transmission member to integrally rotate. And a plate that is adjacent to the intermediate plate of the primary fastening plate group at least when the primary fastening plate group is fastened. A pressing member for pressing in the direction of the member,
It is provided between the primary fastening plate group and the first transmission member or the second transmission member.

According to the second aspect of the present invention, the plurality of first plates and the plurality of second plates are alternately and concentrically arranged, and the plurality of first plates and the plurality of second plates are arranged.
A piston member for pressing the plate against the first member;
In a wet-type multi-plate fastening device in which elastic members are interposed between plates, at least one of the elastic members is provided.
The elastic modulus of one elastic member is smaller than that of the other elastic member.

[0014]

According to the first aspect of the present invention, with the displacement of the piston member, the primary fastening plate group is first pressed against the piston member and the pressing member, and torque transmission is performed by the primary fastening plate group. Done. If the piston member is still displaced while compressing the pressing member, the primary fastening plate group is pressed against the secondary fastening plate group via the intermediate plate, so that the primary fastening plate group and the secondary fastening plate group The torque is transmitted by the plate group consisting of the intermediate plate and the intermediate plate.

According to the second aspect of the present invention, when the elastic member having a smaller elastic coefficient than other elastic members is compressed by the displacement of the piston member, the first plate and the first plate located on both sides of the elastic member are compressed. A second plate located between the plates is pressed into contact, and the plates transmit torque. Then, when the piston member is further displaced while compressing another elastic member, all the first plates and all the second plates are pressed against each other to transmit torque.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. It is to be noted that the same components as those of the related art are denoted by the same reference numerals, and description thereof is omitted.

FIG. 1 is a view showing the configuration of a first embodiment of the present invention, and is a cross-sectional view of a multiple disc clutch as a wet multiple disc fastening device. FIG. 2 shows a clutch piston 7 as a piston member and a driven plate 1 as a first plate.
FIG. 4 is a schematic diagram showing a positional relationship among a retaining plate 3, a drive plate 5 as a second plate, an intermediate plate 10, and a dish plate 13 as a pressing member.

The driven plate 1, the retaining plate 3, and the drive plate 5 are alternately and concentrically arranged to form a plate group.

In the middle of the plate group, a clutch drum 2 is provided.
There is provided an intermediate plate 10 which engages with. The plate group is divided by the intermediate plate 10 into a primary fastening plate group 11 adjacent to the clutch piston 7 and a secondary fastening plate group 12 separated from the clutch piston 7.

Reference numeral 13 denotes a dish plate.
Displacement in the direction of 0 is prohibited.

When the multi-plate clutch is not engaged, the clutch piston 7 and the primary engagement plate group 11 are provided at a distance a from each other. c are provided at intervals. The distance k between the end of the dish plate 13 on the clutch piston 7 side and the primary fastening plate group 11 is k.
, And the end of the dish plate 13 on the clutch piston 7 side and the intermediate plate 10 are provided at an interval l. Further, the intermediate plate 10 and the secondary fastening plate group 12
Are provided at an interval d, and the secondary fastening plate group 12 is mutually separated from the intermediate 10 by e and e.
They are provided at intervals of f, g, h, and i.

Here, the compression j of the dish plate 13 is designed to satisfy the relationship j> d + e + f + g + h + i + 1.

Next, the operation of this embodiment will be described with reference to FIGS.
This will be described with reference to FIG. Here, FIG. 3 is a characteristic diagram of the transmission capacity T of the multi-plate clutch with respect to the stroke x of the clutch piston 7.

When the hydraulic oil is not supplied to the pressure chamber 9, the clutch piston 7 is not displaced toward the driven plate 1, so that the driven plate 1, the retaining plate 3, the drive plate 5, and the intermediate plate 10 are separated from each other. Therefore, torque is not transmitted between the clutch drum 2 and the clutch hub 6.

[0025] is hydraulic oil supplied to the pressure chamber 9, the clutch piston 7 is displaced to the driven plate 1 side, the stroke x of the clutch piston 7 x ₁₁ i.e. a + b + c +
When it reaches k, the primary fastening plate group 11 comes into contact with the dish plate 13. When the clutch piston 7 is further displaced, the dish plate 13
4, the displacement of the intermediate plate 10 in the direction of the intermediate plate 10 is prohibited.
Deforms the dish plate 13. At this time, the repulsive restoring force generated in the dish plate 13 causes 1
The next fastening plate group 11 is pressed against each other between the clutch piston 7 and the dish plate 13 and transmission of torque between the clutch drum 2 and the clutch hub 6 is started.

The clutch piston 7 is driven plate 1
When it is further displaced by 1 to the side, the primary fastening plate group 11 comes into contact with the intermediate plate 10. Clutch piston 7 is further displaced, the stroke reaches x ₁₂ i.e. a + b + c + k + l + d + e + f + g + h + i, 1 primary fastening plate group 11 is 12 and the pressure secondary fastening plate group via the Intermediate over preparative plate 10, the engagement of the multiple disc clutch complete I do.

FIG. 4 shows the characteristics of the operating oil pressure P acting on the pressure chamber 9 and the transmission capacity T. Generally, since the transmission capacity T increases in proportion to the number of plates, while the torque is being transmitted by the primary fastening plate group 11 and the secondary fastening plate group 12, only the primary fastening plate group 11 is transmitted. Transmission capacity T compared to the time during which torque is transmitted
Is large, and the rate of increase of the transmission capacity T with respect to the operating oil pressure P differs at the operating oil pressure P ₁ . The effects of the present embodiment are as follows. First, in this embodiment, since the stroke of the clutch piston 7 the transmission of torque from where it reaches the x ₁₁ is executed, the first transfer torque is performed by the all the driven plates 1 and the drive plate 5 is pressed against In comparison with the related art, the stroke x of the clutch piston 7 required for transmitting the torque is smaller. Therefore, even if the clearance C between the plates is set large to reduce the drag torque,
The select lag can be reduced as compared with the related art.

Further, since the rate of increase accompanied transmission capacity T to increase the hydraulic pressure P as shown in FIG. 4 is smaller than the P ₁ or more ranges in the working oil pressure P ₁ the range, such When a simple wet multi-plate fastening device is used in combination with a duty hydraulic control device, it is possible to finely control a region where the transmission capacity T is low.

In this embodiment, the intermediate plate 10 is provided in engagement with the clutch drum 2, and the dish plate 13 is provided between the primary fastening plate group 11 and the clutch drum 2. However, the present invention is not limited to this. That is, the intermediate plate 10 may be provided in engagement with the clutch hub 6, or the dish plate 13 may be provided between the primary fastening plate group 11 and the clutch hub 6.

Next, a second embodiment of the present invention will be described. FIG. 5 is a view showing the configuration of the second embodiment, and is a cross-sectional view of a multiple disc clutch as a wet multiple disc fastening device. FIG. 6 is a schematic diagram showing a positional relationship between a plate group and a coil spring 15 as a pressing member that replaces the intermediate plate 10 and the dish plate 13.

In the present embodiment, the driven plate 1 of the primary fastening plate group 11 adjacent to the intermediate plate 10 is prevented from being displaced toward the clutch piston 7 by the snap ring 16, and thus such a driven plate is driven. A pre-compressed coil spring 15 is provided between the plate 1 and the snap ring 14.

Further, the dimension m of the drive plate 5 of the primary fastening plate group 11 is such that m> n + 1 + d + e + f + g + h +, where n is the dimension of the snap ring 16 in the axial direction.
i, the driven plate 1 adjacent to the clutch piston 7 when the multi-plate clutch is engaged.
The fastening can be completed before the abutment with the snap ring 16. Other configurations are the same as in the first embodiment.

The operation of this embodiment will be described with reference to FIGS. Here, FIG. 7 is a characteristic diagram of the transmission capacity T of the multi-plate clutch with respect to the stroke x of the clutch piston 7 in the present embodiment.

When the hydraulic oil is not supplied to the pressure chamber 9, the multiple disc clutch is in the non-engaged state as in the first embodiment.

The clutch piston 7 is hydraulic oil supplied to the pressure chamber 9 is displaced to the driven plate 1 side, the stroke reaches x ₂₁ i.e. a + b + c, 1 primary fastening plate group 11 into contact with the coil spring 15 . Since the coil spring 15 is compressed in advance and has a rebound restoring force, the primary fastening plate group 11 is immediately completed between the clutch piston 7 and the coil spring 15, and the clutch drum 2 and the clutch hub 6 are fastened. And transmission of torque is started.

When the clutch piston 7 is further displaced, 1
The next fastening plate group 11 is displaced while compressing the coil spring 15, and the transmission capacity T of the multi-plate clutch gradually increases. The stroke x ₂₂ i.e. a + b + c +
When l + d + e + f + g + h + i is reached, the primary fastening plate group 11 abuts on the intermediate plate 10 and then is pressed against the secondary fastening plate group 12 via the intermediate plate 10 to complete the engagement of the multi-plate clutch.

The characteristics of the operating oil pressure P acting on the pressure chamber 9 and the transmission capacity T are the same as in the first embodiment.

In the present embodiment, since the primary fastening plate group 11 is fastened between the coil spring 15 and the clutch piston 7 which have been compressed in advance, in addition to the effects achieved by the first embodiment, FIG. As shown in FIG. 7, there is an effect that a constant and stable transmission capacity can be obtained at the initial stage of fastening.

Next, a third embodiment of the present invention will be described. FIG. 8 is a view showing a configuration of the third embodiment, and is a cross-sectional view of a multiple disc clutch as a wet multiple disc fastening device.

In this embodiment, a hydraulic piston 17 is provided in place of the coil spring 15 as a pressing member, and a passage 18 for supplying hydraulic oil to the hydraulic piston 17 is provided in the clutch drum 2. I have. Here, it is assumed that an appropriate hydraulic oil is introduced into the hydraulic piston 17 from a control valve (not shown) provided in the automatic transmission. Other configurations are the same as those of the second embodiment.

The operation of this embodiment is the same as that of the second embodiment. That is, in this embodiment, hydraulic oil is introduced into the hydraulic piston 17 through the passage 18, and presses the driven plate 1 adjacent to the hydraulic piston 17 toward the clutch piston 7. Accordingly, as in the second embodiment, the primary fastening plate group 11 is immediately engaged between the clutch piston 7 and the hydraulic piston 17 with the displacement of the clutch piston 17.

In this embodiment, the coil spring 1
By using the hydraulic piston 17 in place of 5, in addition to the effect achieved by the second embodiment, there is an effect that a stable pressing force can always be obtained on the driven plate 1 adjacent to the hydraulic piston 17. Things.

Next, a fourth embodiment of the present invention will be described. FIG. 9 is a diagram showing the configuration of the fourth embodiment, and is a cross-sectional view of a multiple disc clutch as a wet multiple disc fastening device. FIG. 10 shows a plate group and elastic members 19 and 2 as pressing members.
It is a schematic diagram which shows the positional relationship with 0,21,22.

In this embodiment, the intermediate plate 10, the dish plate 13 as a pressing member, the coil spring 15, the hydraulic piston 17, the snap rings 14, 16 and the passage 18 are not provided.

Further, elastic members 19, 20, 21, 22 are provided between the driven plates 1, respectively. Among them, the elastic members 20, 21, 22 have the same elastic modulus k ₂ , k ₃ , k _{4 and} are larger than the elastic coefficient k ₁ of the elastic member 19, so that the elastic members 19, 20, ₂
The relationship between the amount of displacement and the repulsive force when 1 and 22 are compressed is as shown in FIG. The two driven plates 1 adjacent to the elastic member 19 and the drive plate 5 sandwiched between the two driven plates 1 constitute a primary fastening plate group 11, and the other driven plates 1 and the drive plate The secondary fastening plate group 12 is constituted by the retaining plate 3 and the retaining plate 3.

Here, the distance a between the clutch piston 7 and the driven plate 1 adjacent to the clutch piston 7 is
The driven plate 1, the retaining plate 3, and the drive plate 5 are spaced apart from each other by a distance b, c, d, e, f, from the clutch piston 7 side.
It is provided via g, h, and i. Other configurations are the same as those of the first to third embodiments.

FIGS. 10 and 12 show the operation of this embodiment.
This will be described with reference to FIG. Here, FIG. 12 shows the transmission capacity T of the multi-plate clutch with respect to the stroke x of the clutch piston 7.
FIG.

When the hydraulic oil is not supplied to the pressure chamber 9, the multiple disc clutch is in the non-engaged state as in the first to third embodiments.

When hydraulic oil is supplied to the pressure chamber 9 and the clutch piston 7 is displaced toward the driven plate 1 and starts pressing the plate group, the elastic members 19, 20, 21, 21 provided between the driven plates 1 are provided. 22 is also pressed,
Among these, the elastic member 19 having the smallest elastic coefficient is compressed, and a repulsive force is generated in the elastic members 20, 21, 22. The stroke of the clutch piston 7 x ₃₁ i.e. a
When + b + c is reached, the primary fastening plate group 11 is pressed against each other between the clutch piston 7 and the elastic member 20. Thus, transmission of torque between the clutch drum 2 and the clutch hub 6 is started.

[0050] Then the elastic members 20, 21, 22 when the clutch piston 7 is displaced further also compressed, the stroke reaches x ₃₂ i.e. a + b + c + d + e + f + g + h + i, 1 primary fastening plate group 11 secondary fastening plate group 12 integrally with pressure Is done. This completes the engagement of the multi-plate clutch.

The characteristics of the operating oil pressure P acting on the pressure chamber 9 and the transmission capacity T in the present embodiment are as shown in FIG. 3 as in the first embodiment.

In this embodiment, there is no need to provide the intermediate plate 10 as in the first to third embodiments, and the axial dimension does not increase.
In addition to the effects achieved by the embodiment, there is an effect that the space efficiency is excellent. Further, since the elastic members 19, 20, 21, and 22 are provided between the driven plates 1, a clearance C between the driven plate 1 and the drive plate 5 can be secured when the multi-plate clutch is not engaged. There is also an effect that the drag torque can be surely reduced.

In this embodiment, the elastic member 19
Elastic coefficient k ₂ the elastic coefficient k ₁ of the elastic member 20, 21, 22, k _3, it has been set smaller than k _4, by changing the relationship between the elastic modulus _{k 1, k 2, k 3} , k 4 An arbitrary transmission capacitance T characteristic can be obtained. For example, elastic member 1
The elastic moduli of 9, 20, 21, 22 are represented by k ₁ <k ₂ <k ₃ <k ₄
With the setting, since the plate group are sequentially fastened from the clutch piston 7 side, four steps the boundary of transmission capacity increase rate of the T is hydraulic pressure P _1, P _2, P ₃ with respect to hydraulic pressure P as shown in FIG. 13 Becomes

[0054]

As described above, according to the first aspect of the present invention, the plate group composed of the first plate and the second plate is combined with the primary fastening plate group via the intermediate plate. 2 for secondary fastening plate group
In the initial stage of the fastening, the primary fastening plates are used to transmit the torque, so even if the clearance between the plates is set large to reduce the drag torque, the select lag can be reduced compared to the conventional technology. it can.

According to the second aspect of the present invention, an elastic member is interposed between the first plates, and the elastic coefficient of at least one of the elastic members is made smaller than the elastic coefficient of the other elastic member. By setting it to be small, torque is transmitted by the adjacent plate group via an elastic member having a small elastic coefficient in the initial stage of fastening, so that good space efficiency can be obtained in addition to the effect of the first aspect of the invention. At the same time, the clearance between the plates at the time of non-fastening is ensured by the elastic member, so that the drag torque can be more reliably reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of a multiple disc clutch as a wet multiple disc fastening device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a positional relationship among a plate group, an intermediate plate, and a dish plate in the first embodiment.

FIG. 3 is a characteristic diagram of a transmission capacity T of the multiple disc clutch with respect to a clutch piston stroke x in the first embodiment.

FIG. 4 is a characteristic diagram showing a relationship between an operating oil pressure P and a transmission capacity T in the first embodiment.

FIG. 5 is a sectional view showing the structure of a multiple disc clutch according to a second embodiment.

FIG. 6 is a schematic diagram showing a positional relationship among a plate group, an intermediate plate, and a coil spring.

FIG. 7 is a characteristic diagram showing a relationship between a transmission capacity T of a multiple disc clutch and a stroke x of a clutch piston in a second embodiment.

FIG. 8 is a sectional view showing the structure of a multiple disc clutch according to a third embodiment.

FIG. 9 is a sectional view showing the structure of a multiple disc clutch according to a fourth embodiment.

FIG. 10 is a schematic diagram illustrating a positional relationship between a plate group and an elastic member.

FIG. 11 is a characteristic diagram showing a relationship between a compression displacement amount of an elastic member and a repulsive force.

FIG. 12 is a characteristic diagram showing a relationship between a transmission capacity T of a multiple disc clutch and a stroke x of a clutch piston in a fourth embodiment.

FIG. 13 shows an operating oil pressure P and a transmission capacity T in the fourth embodiment.
FIG. 9 is another characteristic diagram showing the relationship with the graph.

FIG. 14 is a cross-sectional view showing the structure of a multi-plate clutch according to a conventional technique.

FIG. 15 is a characteristic diagram showing a relationship between a drag torque and a clearance between plates.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Driven plate (1st plate) 2 Clutch drum (1st transmission member) 5 Drive plate (2nd plate) 6 Clutch hub (2nd transmission member) 7 Clutch piston (piston member) 11 Primary fastening plate group 12 Secondary Fastening plate group 13 Dish plate (pressing member) 15 Coil spring (pressing member) 17 Hydraulic piston (pressing member) 19, 20, 21, 22 Elastic member

Claims (2)

(57) [Claims] A plurality of first plates which rotate integrally with the first transmission member and which are arranged coaxially with the first transmission member and alternately with the first plates; A plurality of second plates that rotate integrally with the member;
A piston member for pressing a plate group consisting of the plurality of first plates and the plurality of second plates; and a primary fastening plate group adjacent to the piston member and a secondary fastening plate group separating from the piston member. An intermediate plate that halves in the axial direction and rotates integrally with the first transmission member or the second transmission member to rotate integrally with the first transmission member or the second transmission member. A pressing member for pressing a plate adjacent to the intermediate plate in the group of fastening plates in the direction of the piston member is provided between the primary fastening plate group and the first transmission member or the second transmission member. Features a wet multi-plate fastening device. 2. The method according to claim 1, further comprising a plurality of first plates and a plurality of second plates arranged alternately and concentrically, and a piston member for pressing the plurality of first plates and the plurality of second plates into pressure. In a wet multi-plate fastening device in which elastic members are interposed between plates, an elastic coefficient of at least one of the elastic members is smaller than an elastic coefficient of another elastic member. Fastening device.