JPH0543296Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention is applicable to various construction machines, various trucks,
Power shift transmissions with built-in hydraulically operated multi-disc clutches are installed in buses, passenger cars, etc.
The present invention relates to a rotating clutch piston device in an automatic transmission.

(Prior Art) The conventional example of the rotary clutch piston device is described in the fourth example.
For the transmission shown in the figure, an inner clutch piston 3a with a seal 6 and an outer clutch piston 3b with a seal 6 are arranged in a piston housing 2 that is attached to an input shaft (not shown) and rotates. A return spring 5b is interposed between the spring retainer 4b on the piston housing 2 side and the outer clutch piston 3b, and the outer clutch piston is spring biased toward the outer piston pressure receiving chamber 7b. The clutch piston etc. are rotated, and the inner and outer clutch pistons 3a,
Hydraulic oil is separately supplied and discharged to the inner and outer piston pressure receiving chambers of the inner and outer clutch pistons 3a and 3b.
b is actuated to individually engage and disengage each clutch plate of the inner and outer clutch parts with the clutch mating plate (not shown), thereby transmitting power from the input shaft to the output shaft via the inner and outer clutch parts. When the clutch is not engaged by the outer clutch piston 3b, the oil in the outer piston pressure receiving chamber 7b disappears, and the outer clutch piston 3b is moved to the outer side by the return spring 5b. The piston is returned to the pressure receiving chamber 7b side (left side in the figure), and the outer clutch plate is separated from the clutch mating plate and no longer transmits power to the output shaft.However, due to the rotation of the remaining oil in the outer piston pressure receiving chamber 7b, the centrifugal hydraulic pressure occurs, and the centrifugal oil pressure exceeds the spring bias of the return spring 5b, causing a problem in which the outer clutch piston 3b is moved to the right in the figure by the centrifugal oil pressure and becomes engaged with the clutch.

As a conventional measure against the above-mentioned problem, a hole 9 with a ball check valve 8 is installed in the outer piston pressure receiving chamber 7b.
is provided, and when the pressure oil in the outer piston pressure receiving chamber 7b disappears, the ball check valve is separated from the seat surface by the action of centrifugal force, the remaining oil in the outer piston pressure receiving chamber is released from the hole 9, and acts on the outer clutch piston 3b. A centrifugal displacement mechanism is provided to reduce centrifugal hydraulic pressure.

Further, as shown in FIG. 5, an outer balance piston chamber 8b is provided on the opposite side to the outer piston pressure receiving chamber 7b.
and oil holes 10a are provided in series to supply lubricating oil to oil hole 1.
0a into the outer balance piston chamber 8b to balance the centrifugal hydraulic pressure generated inside and outside the outer clutch piston 3b, and a centrifugal hydraulic pressure eliminating mechanism is provided in which the outer clutch piston 3b returns only by the return spring 5b.

Note that the centrifugal hydraulic pressure generated on the inner clutch piston 3a side has a relatively small radius of rotation, so it does not have any particular adverse effect on the clutch operation. 1 in the diagram
0b is a seal provided on the outer periphery of the spring retainer 4b.

(Problems to be Solved by the Invention) In the conventional centrifugal hydraulic displacement mechanism, the conventional example shown in FIG. Since all of the oil is discharged to the outside through the hole with the ball check valve, the next time the clutch is engaged, the oil pressure is filled in the oil passage in the middle and then sent into the piston pressure receiving chamber, which lengthens the shift time. In addition, there are many variations in the operating characteristics of the ball check valve, and there is a time delay until the ball check valve comes into close contact with the seat, making it difficult to strictly control the time until the end of oil discharge from the hole with the ball check valve. There are problems such as:

In the conventional example shown in Fig. 5, there is a limit to increasing the seal diameter on the outer periphery of the spring retainer that seals the balance piston chamber due to its mounting structure. The centrifugal hydraulic pressure generated in the balance piston chamber is reduced due to the large radius difference, and in order to cope with this, it is necessary to increase the spring biasing force (returning force) of the return spring, resulting in problems such as an increase in the size of the device. .

The present invention was developed to address the above-mentioned problems, and its purpose is to:
To provide a rotary clutch piston device in which an outer balance piston chamber is provided on the outer clutch piston side, and centrifugal oil pressure generation performance in the outer balance piston chamber is improved to improve centrifugal oil pressure removal performance and operational reliability of the outer clutch piston. be.

(Means for Solving the Problems) The present invention provides an outer balance piston chamber that opposes centrifugal hydraulic pressure on the outer clutch piston side in a rotating clutch piston device in which an inner clutch piston and an outer clutch piston are arranged in a rotating piston housing. The inner piston pressure receiving chamber on the inner clutch piston side is communicated with the inner piston through an orifice.
It is characterized by a centrifugal hydraulic displacement mechanism that forcibly sends the pressure oil in the inner piston pressure receiving chamber into the outer balance piston chamber, and the outer balance piston chamber is provided on the outer clutch piston side.
By forcibly feeding the pressurized oil in the inner piston pressure receiving chamber into the outer balance piston chamber through an orifice, the centrifugal oil pressure generated in the outer balance piston chamber is ensured with respect to the centrifugal oil pressure generated in the outer piston pressure receiving chamber.

(Function) An outer balance piston chamber is provided on the outer clutch piston side, and the pressure oil in the inner piston chamber on the inner clutch piston side is forcibly sent into the outer balance piston chamber through an orifice, and the residual oil in the outer piston chamber rotates. The centrifugal oil pressure generated in the outer balance piston chamber is effectively increased compared to the centrifugal oil pressure generated in the outer balance piston chamber, and excellent centrifugal oil pressure removal function and reliability are obtained in the outer clutch piston. This does not particularly affect the operation of the outer clutch piston, and allows the inner and outer clutch pistons to operate more accurately and smoothly.

(Embodiment) An embodiment of the present invention is shown in FIGS. 1 to 3, in which 11 is an input shaft, 12 is a piston housing that is spline-engaged with the input shaft 11 and rotates;
12a is an outer ring, 13a is an inner clutch piston with a seal 16 disposed within the piston housing 12, and 13b is a piston housing 12.
15a is a return spring interposed between the spring retainer 14a and the inner clutch piston 13a, 15b is a seal 24b, and an O-ring 1.
The return spring is interposed between the spring retainer 14b with 6b and the outer clutch piston 13b, and the inner piston pressure receiving chamber 1 is sealed with a seal 16 on the inner clutch piston 13a side.
7a, and an outer piston pressure receiving chamber 17b sealed with a seal 16, an outer balance piston chamber 18b sealed with an O-ring 16b and a seal 24b are provided on the outer clutch piston 13b side. In a rotating clutch piston device in which an inner clutch piston 13a and an outer piston chamber 13b are arranged, the inner piston pressure receiving chamber 17a on the inner clutch piston 13a side is orifice-shaped in the outer balance piston chamber 18b which opposes the centrifugal oil pressure on the outer clutch piston 13b side. 20, the pressure oil in the inner piston pressure receiving chamber 17a is communicated with the outer balance piston chamber 1.
It is a rotating clutch piston device equipped with a centrifugal hydraulic displacement mechanism that forcibly feeds into the piston 8b.

Further, in this embodiment, a second orifice 21 is provided through the outer spring retainer 14b, and inner clutch portions 22a and 23a consisting of a clutch plate 22a, a clutch mating plate 23a, etc. are provided oppositely to the inner clutch piston 13a. An output shaft 25a is connected to the inner clutch portion, and a clutch plate 22 is connected to the outer clutch piston 13b.
b, outer clutch portions 22b and 23b consisting of a clutch mating plate 23b and the like are provided oppositely, and an output shaft 25b is connected to the outer clutch portions.

In the figure, 26 is a support, 28 is an oil hole in the support,
Outer piston pressure receiving chamber 17 via rotary seal portion 27
b, and there is also a hydraulic oil passage connected to the inner piston pressure receiving chamber 17a (not shown).
are installed in succession.

The embodiment of the present invention has the above-mentioned structure, and its operation will be described in detail.The inner clutch piston 13a is spring-biased toward the inner piston pressure receiving chamber 17a sealed by the return spring 15a, and the outer clutch piston 13a is The piston 13b is
The return spring 15b biases the piston toward the sealed outer piston pressure receiving chamber 17b,
The outer balance piston chamber 18b has a seal 24b.
The rotary clutch piston device rotates together with the input shaft 11, and is sealed by an O-ring 16b, and communicates with the inner piston pressure receiving chamber 17a through an orifice 20, and communicates with the clutch side through a second orifice 21.

In the outer clutch piston 13b, the hydraulic oil flows from the oil hole of the support 26 to the rotary seal portion 27 and the oil passage 28.
When the outer piston pressure receiving chamber 17b is filled, the outer clutch piston 13b is moved to the right in the figure, and the clutch plate 22b is brought into close contact with the clutch mating plate 23b, resulting in clutch engagement, and power is transferred to the output shaft 25b. When the inner clutch piston 13a is supplied with hydraulic oil through another oil passage (not shown) and is filled with the inner piston pressure receiving chamber 17a, the inner clutch piston 13a
3a is moved to the right in the figure and the clutch plate 22
a comes into close contact with the clutch mating plate 23a, resulting in clutch engagement, resulting in an operation in which power is transmitted to the output shaft 25a. When the hydraulic oil is discharged, the inner and outer clutch pistons 13a, 13b are returned to the left in the figure by the return springs 15a, 15b, and the clutch is disengaged, resulting in a non-operating state in which no power is transmitted to the output shafts 25a, 25b. .

The rotating clutch piston device shown in FIG. 1 is applied to a Simpson gear train as shown in FIG. 2 (skeleton diagram). 30 in the figure is the first
The rotating clutch piston device shown in the figure,
Output shaft 25 of the rotating clutch piston device 30
a, 25b are planetary gear mechanism G, multi-stage clutch
B ₁ , B ₂ , and B ₃ are connected to
As shown in the figure, reverse R, neutral N, each stage 1, 2,
3, 4, and the inner clutch parts 22a, 23a and the outer clutch parts 22b,
23b and each of the clutches B ₁ , B ₂ , B ₃ are actuated as shown in FIG. 3 (0 indicates clutch engagement).

Next, the function of removing centrifugal hydraulic pressure will be explained in detail.As shown in FIG.
When the clutches 22a and 23b are at a speed stage in which the clutches are not engaged, the inner clutch portions 22a and 23b are in the engaged state. That is, when the clutch engagement of the outer clutch plate 22b is released, hydraulic oil is supplied to the inner piston pressure receiving chamber 17a on the inner clutch piston 13a side, and the inner clutch piston 13a is moved to the right in the figure. Centrifugal oil pressure is generated in the remaining oil in the outer piston pressure receiving chamber 17b due to rotation, but the pressure oil in the inner piston pressure receiving chamber 17a passes through the orifice 20 and is transferred to the outer balance piston chamber 18b.
, and a force is applied inside the outer balance piston chamber 18b to push the outer clutch piston 13b back to the left in the figure.

The outer balance piston chamber 18b is sealed with a seal 24b and an O-ring 16b attached to the spring retainer 14b, and the second orifice 21
is set smaller than orifice 20,
A return force due to the spring force of the return spring 15b and the hydraulic pressure acting on the outer balance piston chamber 18b acts on the outer clutch piston 13b. The hydraulic pressure flowing from the orifice 20 into the outer balance piston chamber 18b always flows into the outer clutch piston chamber 1.
It is designed to have a higher pressure than the centrifugal hydraulic pressure working in the outer piston pressure receiving chamber 18b and a lower pressure than the clutch hydraulic pressure supplied to the outer piston pressure receiving chamber 18b when the clutch is engaged, so that the outer clutch piston 13b is always pushed to the left in the figure. When hydraulic oil is supplied to the outer piston pressure receiving chamber 17b, the piston immediately moves to the right in the figure and transmits power.

Furthermore, when both the outer clutch piston 13b and the inner clutch piston 13a are engaged, pressure oil is sent from the orifice 20 to the outer balance piston chamber 18b and is filled, so that the outer clutch piston 13b is moved to the right in the figure. However, the outer piston pressure receiving chamber 1
Since there is a large difference between the clutch oil pressure acting in the clutch 7a and the oil pressure acting in the outer balance piston chamber 18b, the shift feeling does not deteriorate.

Regarding the influence of centrifugal hydraulic pressure on the inner clutch piston 13a, since the rotation radius is smaller than that on the outer side, even if centrifugal hydraulic pressure is generated, it will not have a particular effect on clutch operation, and if a malfunction occurs due to centrifugal hydraulic pressure, This problem can be solved by providing a balance piston chamber on the inside like the outer clutch piston 13b. In addition, the inner clutch piston 13a is a forward clutch as shown in FIG. 3, and the inner clutch portion is always engaged during forward movement, so the influence of centrifugal oil pressure by the inner clutch piston 13a is small. Become.

(Effects of the invention) The present invention has the above-mentioned configuration, in which the pressure oil in the inner piston chamber is forcibly fed into the outer balance piston chamber provided on the outer clutch piston side by an orifice, and the outer clutch piston The centrifugal hydraulic pressure generated on the outside of the clutch piston is effectively balanced, and the centrifugal hydraulic pressure rejection performance and reliability of the outer clutch piston are significantly improved.

In addition, there is no need to provide a mechanism for discharging the residual oil in the outer piston chamber, and the feeding of the pressure oil through the orifice does not have any particular effect on the operation of the inner and outer clutch pistons, allowing accurate operation of the inner and outer clutch pistons. It is faster, has improved clutch actuation performance, and is provided at a lower cost.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view showing an embodiment of the present invention, Fig. 2 is a skeleton diagram showing an example of application of Fig. 1, and Fig.
The figure shows the clutch engagement of each speed stage in Fig. 2, Fig. 4 is a vertical cross-sectional view of the main part of the transmission clutch section showing a conventional example, and Fig. 5 is a longitudinal cross-sectional view of the main part showing another conventional example. It is. 12...Piston housing, 13a...Inner clutch piston, 13b...Outer clutch piston, 17a...Inner piston pressure receiving chamber, 18b...
...Outer balance piston chamber, 20...orifice.

Claims (1)

[Scope of utility model registration request] In a rotating clutch piston device in which an inner clutch piston and an outer clutch piston are arranged in a rotating piston housing, an inner piston pressure receiving chamber on the inner clutch piston side is connected to an outer balance piston chamber opposing centrifugal hydraulic pressure on the outer clutch piston side by an orifice. A rotary clutch piston device characterized by being provided with a centrifugal hydraulic displacement mechanism that communicates with the inner piston pressure receiving chamber and forcibly sends the pressure oil in the outer balance piston chamber.