JPH0324900Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention includes a check valve device, in particular, a valve seat and a check ball for opening and closing the valve seat, and
The present invention relates to an improvement in a check valve device that is incorporated in a location where centrifugal force (including its component force; the same applies hereinafter) acts on the check ball.

[Conventional technology]

Equipped with a gear transmission mechanism and multiple frictional engagement devices,
Automatic transmissions for vehicles configured to selectively switch the engagement of the frictional engagement device by operating a hydraulic control device to achieve one of a plurality of gears have already been widely used. Are known. Some check valve devices are generally incorporated into the hydraulic control system to control the flow of oil in its oil passages. This check valve device includes a valve seat and a check ball that opens and closes the valve seat, and is used for the purpose of allowing oil in an oil passage to flow in only one direction.

[Problem that the invention attempts to solve]

However, generally, the frictional engagement devices used in automatic transmissions are arranged at circumferential positions on the same radius around the rotating shaft, and therefore, it is difficult to control such frictional engagement devices. Since the check valve device, which is one of the devices, can also be affected by centrifugal force, this effect sometimes interferes with the check valve's original closing function, and the check valve does not close smoothly at the intended time. There was a problem that there was.

[Purpose of invention]

The present invention was developed in view of these conventional problems, and aims to provide a check valve device that is not affected by centrifugal force and can smoothly open and close as intended at the intended time. purpose.

[Means to solve the problem]

The present invention provides a check valve device that includes a valve seat and a check ball that opens and closes the valve seat, and that is incorporated in a location where centrifugal force acts on the check ball, in which the check ball is made of a magnetic material. In addition, the above object is achieved by arranging a centrifugal force canceling magnet on the center side of the centrifugal force of the check ball. Further, in the embodiment of the present invention, by employing a permanent magnet as the magnet, the influence of centrifugal force can be offset or reduced with a simple and low-cost configuration. In another embodiment of the present invention, an electromagnet that is excited to generate an attractive force corresponding to the centrifugal force is used as the magnet, so that the influence of the centrifugal force is quantitatively and accurately offset; This makes it possible to minimize the influence of centrifugal force.

[Effect]

In the present invention, the check ball is made of a magnetic material that can be attracted by a magnet, and the magnet is placed on the center side of the centrifugal force of the check ball, so that the check ball cannot be attracted by the magnet. This suction force can offset or reduce centrifugal force. As a result, the closing function of the check ball is not hindered by centrifugal force, and the intended opening and closing can always be performed smoothly regardless of the degree of centrifugal force, that is, the rotational speed of the rotating shaft.

【Example】

Embodiments of the present invention will be described in detail below based on the drawings. FIG. 1 shows a part of a clutch device for a vehicle automatic transmission to which an embodiment of the check valve device according to the present invention is applied. In this embodiment, a frictional engagement device 12 is arranged on the same radius around the rotating shaft 10, and a check valve is incorporated in a hydraulic control device 14 for operating the frictional engagement device 12. Equipment A ₁ , A ₂
An example is shown in which the axis is affected by centrifugal force in the directions of arrows X ₁ and X ₂ in the figure. First, the entire clutch device will be explained. A piston 18 is slidably fitted into a cylinder 16. The cylinder 16 is formed by connecting the clutch drum 20 and the shaft end of the rotating shaft 10. This cylinder 16 is provided with a partition part 22, and the cylinder 1
A first chamber 24 and a second chamber 26 are formed between the piston 6 and the piston 18 and are partitioned by the partition portion 22 . The first chamber 24 is located at a radially inner position and is formed as a small volume annular chamber, and the second chamber 26 is located at a radially outer position and is formed as a large volume annular chamber. A small diameter communication passage 30 (shown in the lower half of FIG. 1) is provided in the partition portion 22 of the cylinder 16, and communicates the first chamber 24 and the second chamber 26. In addition, this partition portion 22 has a drain passage 3.
2 (shown in the upper half of FIG. 1), and this drain passage 32 also communicates between the first chamber 24 and the second chamber 26. A check valve device A ₁ is installed in the opening of the first chamber 24 of the drain passage 32 . This check valve device A ₁ allows oil to flow only from the second chamber 26 to the first chamber 24 via the drain passage 32 . As shown in detail in FIG. 2, this check valve device _A1 includes an oil inflow portion 34 from a drain passage 32, a valve seat 36, a check ball 38 formed of a magnetic material, and an oil inflow portion 34 into the first chamber 24. An oil outflow portion 40 is provided, and a valve wall 42 extending from the valve seat 36 to the outflow portion 40 is formed in a tapered shape. This check valve device _A1 is positioned so that its check ball 38 reciprocates in parallel with the rotating shaft 10 to open and close the valve seat 36. Further, this clutch device is provided with a check valve device _A2 that allows oil to flow only from the friction engagement device 12 side to the second chamber 26 side, and has the same configuration as the check valve device _A1 . ing. In these check valve devices A ₁ and A ₂ , permanent magnets S ₁ and S ₂ for canceling the centrifugal forces X ₁ and X ₂ are arranged on the center side of the centrifugal forces X ₁ and X ₂ . On the other hand, the rotating shaft 10 has a hydraulic oil supply oil passage 44.
is provided. The hydraulic oil in the supply oil passage 44 is further led to the first chamber 24 via a supply oil passage 46. A spring seat 48 is fixedly attached to the tip of the rotating shaft 10. A coil spring 52 is interposed between the spring seat 48 and the piston 18. This coil spring 52 is connected to the piston 1
8 in FIG. 1, it is always biased to the left. Therefore, the first chamber 24 and the second chamber 26
When no hydraulic pressure is supplied to the piston 18, the piston 18 is positioned in contact with the side wall of the cylinder 16, as shown in FIG. The friction engagement device 12 is formed of a so-called multi-plate type in which a large number of friction materials 54 and disk plates 56 are alternately arranged. Each friction material 54 is
At its inner peripheral portion, it is attached to a hub of another rotation transmitting member (not shown) by claw engagement so that it is integral in the rotational direction but movable in the axial direction. Similarly, each disk plate 56 is attached at its outer periphery to the outer circumferential wall of the cylinder 16 by claw engagement so that it is integral in the rotational direction but movable in the axial direction. This frictional engagement device 12 is stopped by a stop ring 62 attached to the outer peripheral wall of the cylinder 16 to prevent it from coming off. Moreover, the piston 18 of the frictional engagement device 12
A disk spring 64 is disposed on the side that comes into contact with. Next, the effect will be explained. First, the first chamber 24
The flow of hydraulic oil between the first chamber 26 and the second chamber 26 is performed as follows. When hydraulic oil is supplied from the first chamber 24 to the second chamber 26, the drain passage 3
2 is blocked by the check ball 38, so
This is done only through the communication path 30. Conversely, when the hydraulic fluid is returned from the second chamber 26 to the first chamber 24, it is carried out through both the drain passage 32 and the communication passage 30 because the check ball 38 opens the valve seat 36. Therefore, when the frictional engagement device 12 is in the engaged state, the hydraulic oil flows through the supply oil passages 44 and 46.
First, since the hydraulic pressure is supplied to the first chamber 24, the piston 18 is operated by the hydraulic pressure supplied to the first chamber 24. 1st chamber 24
Since it has a small capacity, a large stroke operation is quickly performed with a small amount of hydraulic oil, and this operation closes the clearance of the friction engagement device 12,
A frictional engagement start state is established to achieve a shift state. Next, when the second chamber 26 is filled with the hydraulic oil supplied through the communication passage 30, the piston 18 is pressed with a strong pressing force due to the addition of hydraulic pressure from the second chamber 26. The engaged state of the frictional engagement device 12 is maintained, and the frictional engagement device 12 is brought into a completely engaged state without slipping. The timing of transition of the frictional engagement device 12 from the engagement start state to the complete engagement state, which achieves the speed change state, is determined by the size of the communication path 30. The communication path 30 generally has a small diameter, and the transition timing is suitable. This also helps to reduce the shift shock. When the engagement state of the frictional engagement device 12 is released, the hydraulic oil in the supply oil passage 44 is brought into a discharged pressure state.
As a result, the hydraulic oil in the second chamber 26 is drained through the first chamber 24 and into the supply oil passages 46,44. At this time, from the second chamber 26 to the first
Since the drain is connected to the chamber 24 through both the communication passage 30 and the drain passage 32, even when the oil is at low temperatures and has high viscosity, or when a strong centrifugal force is applied at high rotational speeds, it is possible to drain only through the communication passage 30. The hydraulic oil in the second chamber 26 is quickly removed compared to the case. Therefore, the return operation of the piston 18 is also carried out quickly and the delay is minimized. In this case, in the above embodiment, for example, taking the check valve device _A1 as an example, the check ball 38 is made of a magnetic material, and the center side of the centrifugal force of the check ball 38, that is, the rotation Since the centrifugal force canceling magnet _S1 is arranged on the shaft 10 side, the check ball 38 of the check valve device _A1 is not influenced by centrifugation and its closing action is not hindered. That is, as shown in FIG. 2, when the centrifugal force acting on the check ball 38 is F ₁ and the hydraulic pressure is F ₂ , F ₁ cos θ is larger than F ₂ cos θ (π/2−θ). If the check ball 38 becomes larger, the force that tries to open the check ball 38 due to centrifugal force becomes stronger than the force that tries to close it due to hydraulic pressure, and its function is inhibited. However, due to the attractive force of magnet S ₂ ,
By offsetting or reducing this centrifugal force F ₁ , the check ball 38 receives a greater closing force due to the hydraulic pressure F ₂ and its smooth function is ensured. Exactly the same operation is performed in the check valve device _A2 . In the above embodiment, permanent magnets were used as the magnets S ₁ and S ₂ to simplify the configuration and reduce costs, but the magnets in the present invention are limited to permanent magnets. Instead, for example, an electromagnet capable of generating an attractive force corresponding to centrifugal force may be used. The attractive force corresponding to the centrifugal force can be easily created by making the excitation current applied to the electromagnet dependent on the rotational speed of the rotating shaft 10. With such a configuration, the influence of centrifugal force can be quantitatively and accurately offset, and precise opening/closing control can be performed smoothly.

[Effect of the idea]

As explained above, according to the present invention, a check valve device installed in a place where centrifugal force acts can perform its original opening/closing function well without being affected by centrifugal force. This excellent effect can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing a part of a clutch device of an automatic transmission for a vehicle to which the check valve device according to the present invention is applied, and Fig. 2 is an enlarged view of the vicinity of check valve device _A1 in the above embodiment. FIG. A ₁ , A ₂ ... Check valve device, S ₁ , S ₂ ... Permanent magnet, 10 ... Rotating shaft, 12 ... Friction engagement device,
14...Hydraulic control device, 16...Cylinder, 18
...Piston, 24...First chamber, 26...
Second chamber, 32...Drain oil path, 34...Inflow section, 36...Valve seat, 38...Check ball,
40...Outflow part.

Claims (1)

[Claims for Utility Model Registration] (1) A check valve device comprising a valve seat and a check ball for opening and closing the valve seat, and installed in a location where centrifugal force acts on the check ball, A check valve device characterized in that the ball is made of a magnetic material and a magnet for canceling the centrifugal force is arranged on the center side of the centrifugal force of the check ball. (2) The check valve device according to claim 1, wherein the magnet is a permanent magnet. (3) The check valve device according to claim 1, wherein the magnet is an electromagnet that is excited to generate an attractive force corresponding to the centrifugal force.