JPH063246Y2 - Negative pressure responsive hydraulic control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] <Industrial field of application> The present invention relates to a negative pressure responsive hydraulic pressure control device, and more particularly to a diaphragm type negative pressure responsive hydraulic pressure control device.

<Prior Art> A diaphragm-type fluid configured to use a diaphragm to move a spool valve by displacement of the diaphragm according to the pressure in the diaphragm chamber and to control the pressure or flow passage of various fluids by the movement of the spool valve. Pressure control valves are well known in the art and are disclosed in, for example, Japanese Patent Laid-Open No.
-43731, 57-54707, 6
It is shown in each publication of 3-140186.

Further, as a diaphragm type fluid pressure control valve, a negative pressure chamber to which a negative pressure such as an intake pipe negative pressure of an internal combustion engine is exerted is provided on one side, and a diaphragm for defining an atmospheric pressure chamber is provided on the other side. A bore of a valve body provided adjacent to the air pressure chamber is configured to control a hydraulic pressure such as a hydraulic pressure according to a negative pressure of the negative pressure chamber by driving a spool valve according to a displacement of the diaphragm. A negative pressure responsive hydraulic control device has been considered.

<Problems to be solved by the invention> In the negative pressure-responsive hydraulic pressure control device as described above, the atmospheric pressure introducing passage to the atmospheric pressure chamber also serves as the drain passage for the hydraulic fluid provided in the valve body. There are things that have been done. In the case of this type of hydraulic control device, if the diaphragm is damaged for some reason and the negative pressure chamber and the atmospheric pressure chamber are in communication with each other, negative pressure is also applied to the drain passage that introduces atmospheric pressure into the atmospheric pressure chamber. As a result, the hydraulic fluid is sucked into the negative pressure source through the negative pressure chamber, and the negative pressure source is hindered. When the negative pressure source is, for example, the intake pipe negative pressure of the internal combustion engine, hydraulic fluid, for example, hydraulic oil, is sucked into the intake passage of the internal combustion engine. When hydraulic oil is sucked into the intake passage of an internal combustion engine, the amount of white smoke in the exhaust gas increases, which adversely affects various sensors provided in the intake passage or the exhaust passage. There is a risk of damaging internal combustion engine accessories such as

In view of the above-mentioned problems, the present invention, even if the diaphragm is damaged and the negative pressure chamber and the atmospheric pressure chamber are in communication with each other,
Provided is an improved negative pressure responsive hydraulic pressure control device which prevents the hydraulic fluid from being sucked toward the negative pressure chamber side and also collects the leaked hydraulic fluid leaking to the atmospheric pressure chamber. Is intended.

[Means for Solving the Problems] <Means for Solving the Problems> According to the present invention, the above-described object is to provide a negative pressure chamber into which the negative suction pressure of the engine is introduced and an atmospheric pressure chamber into which the atmospheric pressure is introduced. A diaphragm body which is isolated from each other by a diaphragm, and a valve body which has a built-in spool valve that moves according to the displacement of the diaphragm and is connected to the atmospheric pressure chamber side of the diaphragm body. And a negative pressure responsive hydraulic pressure control device for controlling hydraulic pressure by changing the degree of communication of a hydraulic oil passage provided inside the valve body due to movement of the spool valve in accordance with negative pressure in the negative pressure chamber. Atmosphere release port is provided at the bottom of the atmospheric pressure chamber, and the atmosphere release port is an air bleed chamber provided on the liquid surface of a case that stores hydraulic fluid whose fluid pressure is controlled by the spool valve. In a row It is achieved by providing a negative 圧応 dynamic type fluid pressure control apparatus characterized by being connected.

<Operation> With this configuration, since the atmospheric pressure chamber can be directly communicated with the air bleed chamber, even if the atmospheric pressure chamber and the negative pressure chamber are communicated with each other due to the damage of the diaphragm, the operation is performed. It becomes difficult for the liquid to be sucked toward the negative pressure chamber side.
Further, the hydraulic fluid leaking into the atmospheric pressure chamber is also collected in the hydraulic fluid storage section in the case through the air bleed chamber when the engine is stopped.

<Embodiment> An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 and FIG. 2 are one embodiment in which the negative pressure responsive hydraulic pressure control device according to the present invention is applied as an intake pipe negative pressure responsive hydraulic control device for obtaining a hydraulic pressure equivalent to throttle hydraulic pressure in an automatic transmission. An example is shown. In these figures, 10 is a negative pressure responsive hydraulic control valve, which is a screw 16
The valve body 12 and the diaphragm body 14 are connected to each other by.

The valve body 12 has a bore 18, a hydraulic inlet port 20 opening to the bore, a hydraulic outlet port 22 and
It has two drain ports 24 and 26. The hydraulic inlet port 20 and the hydraulic outlet port 22 are indicated by the same reference numerals in FIGS. 1 and 2, respectively, and the portions shown in FIG. 1 and the portions shown in FIG. 2 are different from each other. Valve body 12
It communicates with an internal passage (not shown). As a result, the hydraulic inlet port 20, the hydraulic outlet port 22, and the two drain ports 24 and 26 are all attached to the mounting surface 28 of the valve body 12 to the hydraulic control device main body (not shown).
It is open to. The surface of the valve body 12 opposite to the mounting surface 28 is closed by a cover plate 32 mounted on the valve body with bolts 30 sandwiching a seal member 31.

A spool valve 34 is fitted in the bore 18 so as to be movable in the axial direction. The spool valve 34 is disposed in an oil chamber 36 provided at a lower end portion in the drawing of the spool valve 34 toward a position defined by a connecting rod 39 that abuts an upper end surface 35 of the spool valve 34 in the drawing. The hydraulic pressure outlet port 22 is biased by the pressing force by the hydraulic pressure and the spring force of the compression coil spring 38, and the degree of connecting the hydraulic pressure outlet port 22 to the hydraulic pressure inlet port 20 and the drain port 26 is increased or decreased in a mutually contradictory relationship. The hydraulic pressure of 22 is adjusted.
The oil chamber 36 communicates with the hydraulic pressure outlet port 22 by an orifice 42 and an oil passage 44 provided in the spool valve 34, and hydraulic pressure is exerted from this.

The connecting rod 39 has a communicating hole 46 formed in the connecting end portion 15 of the diaphragm body 14 with respect to the valve body 12.
Is located in the diaphragm body 14 so as to extend therethrough, and is engaged with the lower end portion of the connecting member 40 in the diaphragm body 14, that is, in the atmospheric pressure chamber 54 described later.

A diaphragm cover 48 is caulked to the end of the diaphragm body 14 on the side opposite to the connection end to the valve body 12, and the caulking joint between the diaphragm cover and the diaphragm body 14 is made of rubber or a rubber-like product. The diaphragm 50 configured by is fastened together.

The diaphragm 50 includes a negative pressure chamber 52 on the side of the diaphragm cover 48 and an atmospheric pressure chamber 5 on the side of the diaphragm body 14.
4 are each bounded.

The diaphragm cover 48 is provided with a negative pressure port 56. The negative pressure port is connected to an intake manifold of an internal combustion engine by a hose or the like (not shown) so as to guide the intake pipe negative pressure to the negative pressure chamber 52. It has become. A spring retainer 58 is mounted on the negative pressure chamber 52 side of the diaphragm 50, and a compression coil spring 64 is provided between the spring retainer 58 and another spring retainer 62 supported by the diaphragm cover 48 by an adjuster 60. Installed.

The upper end portion of the connecting member 40 and the one end portion 68 of the aneroid bellows 66 are fixedly connected to the atmospheric pressure chamber 54 side of the diaphragm 50. The aneroid bellows 66 is fixed to the diaphragm body 14 by a screw 73 at the other end 70 and extends with the decrease of the atmospheric pressure to extend the initial position of the diaphragm 50, in other words, the initial positions of the connecting member 40 and the connecting rod 39. The spool valve 34 is changed to perform atmospheric pressure compensation for pressure regulation control by the spool valve 34.

An atmosphere opening port 72 is provided at a connection end 15 of the diaphragm body 14 with the valve body 12, and a connection port communicating with the atmosphere opening port 72 is provided at a connection end 13 of the valve body 12 with the diaphragm body 14. 7
4 are provided. The connection port 74 is connected by a hose 76 to a connection port 80 provided on an upper portion of a transmission case 78 of the automatic transmission and communicates with an air bleed chamber 82 inside the transmission case.

Below the transmission case 78, there is an oil reservoir for hydraulic oil to be supplied to the hydraulic pressure inlet port 20, and at the top of the transmission case 78, an air bleed port 84 is provided.

According to the above-described configuration, the negative pressure chamber 5 is connected to the negative pressure chamber 5 through the negative pressure port 56.
As the diaphragm 50 moves upward in the drawing against the spring force of the compression coil spring 64 in accordance with the negative pressure applied to 2, the connecting member 40 and the connecting rod 39 move upward in the drawing. As a result, the specified position given to the spool valve 34 changes. As a result, the hydraulic pressure outlet port 22 produces a hydraulic pressure that generally decreases as the negative pressure in the negative pressure chamber 52 increases.

If the diaphragm 50 is not damaged, the negative pressure of the negative pressure chamber 52 does not reach the atmospheric pressure chamber 54, and the atmospheric pressure chamber 5
No. 4 is opened to the atmosphere through the air bleed port 84 of the transmission case 78, and the atmospheric pressure is exerted.

When the diaphragm 50 is damaged for some reason and the atmospheric pressure chamber 54 is in communication with the negative pressure chamber 52, a negative pressure is exerted on the atmospheric pressure chamber 54. But atmospheric pressure chamber 5
4 is an atmosphere opening port 72, a connection port 74, a hose 7
6 、 Transmission case 7 via connection port 80
Since it communicates with the air bleed chamber 82 of No. 8, the air is sucked into the atmospheric pressure chamber 54 from the air bleed port 84 of the transmission case 78, which makes the atmospheric pressure chamber 54 as strong as the negative pressure chamber 52. A negative pressure state is avoided. For this reason, even if the hydraulic oil in the bore 18 leaks from the communication hole 46 to the atmospheric pressure chamber 54, this leaks the negative pressure chamber 52 and further the negative pressure source for applying a negative pressure to the intake chamber of the internal combustion engine. It never reaches the manifold.

Further, the hydraulic oil leaking to the atmospheric pressure chamber 54 is the atmosphere release port 72, the connection port 74, the hose 76, the connection port 8
After reaching 0, it reaches the air bleed chamber 82 and is collected in the oil sump.

[Effects of the Invention] According to the present invention, even if the diaphragm is damaged, the atmospheric pressure chamber is in direct communication with the air bleed chamber, so that the atmospheric pressure chamber is in a strong negative pressure state. Is prevented. As a result, it is possible to prevent a problem in which the hydraulic fluid is sucked toward the negative pressure chamber and is sucked into the intake manifold of the internal combustion engine, and fail-safe is achieved. Further, the hydraulic oil leaking to the atmospheric pressure chamber returns to the hydraulic fluid storage section in the case through the air bleed chamber when the engine is stopped, so that the hydraulic oil is not lost.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment in which a negative pressure responsive hydraulic pressure control device according to the present invention is applied as an intake pipe negative pressure responsive hydraulic control device, and FIG. 2 is shown in FIG. It is the front view which looked at the hydraulic control valve in a hydraulic control device from the side of the mounting surface. 10 ... Negative pressure responsive hydraulic control valve 34 ... Spool valve, 50 ... Diaphragm 52 ... Negative pressure chamber, 54 ... Atmospheric pressure chamber 72 ... Atmosphere opening port, 74 ... Connection port 76 ... Hose 78 ... Transmission case 80 ... Connection port, 82 ... Air bleed room

Claims (1)

[Scope of utility model registration request] 1. A diaphragm body which separates a negative pressure chamber into which an intake negative pressure of an engine is introduced and an atmospheric pressure chamber into which atmospheric pressure is introduced by a diaphragm, and moves according to the displacement of the diaphragm. And a valve body that is connected to the atmospheric pressure chamber side of the diaphragm body and that is provided by moving the spool valve according to the negative pressure of the negative pressure chamber. In a negative pressure responsive hydraulic pressure control device for controlling hydraulic pressure by changing the degree of communication of a hydraulic oil passage provided inside a valve body, an atmospheric opening port is provided at the bottom of the atmospheric pressure chamber, and the atmospheric opening port is provided. The negative pressure responsive hydraulic pressure control device is characterized in that the port is connected to an air bleed chamber provided on a liquid surface of a case that stores hydraulic fluid whose hydraulic pressure is controlled by the spool valve.