JP2924628B2 - Hydraulic control 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 hydraulic control device,
In particular, the present invention relates to a supply hydraulic pressure switching means for switching a supply / discharge state of hydraulic pressure to / from the hydraulic operation mechanism.

[0002]

2. Description of the Related Art A torque converter of an automatic transmission is connected to an impeller (input element) connected to a crankshaft of an internal combustion engine and rotatably provided integrally with a front cover of the torque converter, and to an input shaft of a gear transmission. A turbine (output element) provided so as to be able to transmit torque to and from the impeller via hydraulic oil, and to transmit the driving force of the engine to the gear transmission. In order to improve the fuel efficiency of an engine used with this type of automatic transmission, a direct connection mechanism for directly connecting the impeller and the turbine is provided in the torque converter to eliminate energy loss between the impeller and the turbine. It is known that a torque converter is deactivated in a state where an impeller and a turbine are directly connected.

The direct connection mechanism belongs to a hydraulic control apparatus having a hydraulic operation mechanism that responds to a hydraulic pressure supplied and discharged by a supply hydraulic pressure switching means that operates under the control of the control means. As shown in FIG. A damper clutch (hydraulic operating mechanism) 12 connected to the turbine of the torque converter 10 and capable of pressing and separating from the front cover 11, and a hydraulic pressure acting in the direction of pressing or releasing the damper clutch to the torque converter 10. A damper clutch control valve (supply hydraulic pressure switching means) 20 and a solenoid valve (control means) 50 for supplying control pressure to the damper clutch control valve are provided.

[0004] The damper clutch control valve 20 includes a spool 21 disposed in the valve body, a spring 22 for pressing the spool 21,
The spool 21 moves according to the hydraulic pressure acting on the end surfaces of the lands 41 to 46 and the spring force of the spring 22 to move the ports 31 to 40.
40 is opened and closed. The solenoid valve 50 is a normally-open type, and includes an excitation coil 55 mounted on a solenoid valve main body having ports 51 to 54 formed therein,
A core 56 that receives an electromagnetic attraction force due to energization of the core 56, a spring 57 that urges the core 56 in the valve opening direction, and a ball-shaped valve body 58 that is movable integrally with the core 56. Reference numeral 60 indicates an oil cooler, and 61 and 62 indicate pressure check ports.

When the select lever is in the N range, for example, in the direct connection mechanism having the above-described structure, the line pressure is not supplied to the port 51 of the solenoid valve 50 and the line pressure is supplied to the port 32 of the damper clutch control valve 20. The spool 21 of the valve 20 assumes the right limit position shown in FIG. In this case, the torque converter pressure working oil chamber defined between the port 34 of the control valve 20 and the lands 42, 43 of the control valve 20,
Through the port 38 of the control valve 20 and the port 13 of the torque converter 10, the torque converter pressure
0 and acts in the direction away from the damper clutch, so that the impeller and the turbine are not directly connected.

When the select lever is in the D range, the line pressure is supplied to the port 36 of the damper clutch control valve 20 via the ports 51 and 52 of the solenoid valve 50. At this time, if the energization to the excitation coil 55 of the normally-open solenoid valve 50 is stopped, the port 5 of the solenoid valve 50 is closed.
The line pressure is always supplied to the control pressure working oil chamber of the control valve 20 via the port 31 of the damper clutch control valve 20 communicating with the port 53. In this case, the spool 21 of the control valve 20 remains in the right limit position shown in FIG. 1, and therefore, as in the case described above, the impeller and the turbine are kept in a non-direct connection state.

When the select lever is in the D range, the energization of the excitation coil 55 of the normally open solenoid valve 50 is duty-controlled.
The communication between the port 51 and the port 53 of the solenoid valve 50 is blocked by the valve body 58. Therefore, the solenoid valve 50
The average oil pressure supplied to the control pressure oil chamber of the control valve 20 via the ports 51 and 53 of the control valve 20 and the port 31 of the damper clutch control valve 20 decreases as the duty ratio increases. When the duty ratio is, for example, 100%, the spool 21 of the control valve 20 assumes the left limit position shown in FIG. 2, and the line pressure supplied to the port 32 of the control valve 20 is It is fed into the torque converter 10 via 37, 40, 39 and the port 14 of the torque converter 10 and acts in the direction of pressing the damper clutch, so that the impeller and the turbine are directly connected. The line pressure supplied to the port 32 is always supplied regardless of the position of the select lever.

[0008]

According to the conventional direct coupling mechanism shown in FIG. 1, it is possible to control the impeller and the turbine in the direct coupling state or the non-direct coupling state as described above. However, in this direct coupling mechanism, when the select lever is switched from the N range to the D range, for example, the direct coupling state of the damper clutch 12 may be unintentionally established regardless of the duty ratio of the solenoid valve 50. Hereinafter, the reason will be described.

In the direct coupling mechanism shown in FIG. 1, there is a slight clearance between the outer peripheral surface of the land 46 of the damper clutch control valve 20 and the inner peripheral surface of the sleeve 47. Oil or air in the line pressure working oil chamber defined between 46 can leak through the clearance with the supply of the line pressure to the oil chamber. On the other hand, oil or air in the control pressure oil chamber communicating with the port 31 of the damper clutch control valve 20 cannot leak from the oil chamber. That is, this oil chamber is
This is because the line pressure is always supplied to the port 32 though the port 32 communicates with the port 32 via a slight clearance between the outer peripheral surface of the control valve body 1 and the inner peripheral surface of the control valve body.

For the above reason, for example, when air is accumulated in both the control pressure oil chamber of the control valve 20 and the line pressure oil chamber defined between the lands 45 and 46, the select lever is set to the N range. From the range to the D range, the air accumulated in the line pressure oil chamber is discharged with the supply of the line pressure to the oil chamber via the port 36 of the control valve 20, so that the oil pressure in the oil chamber is quickly increased. stand up. On the other hand, even if the line pressure as the control pressure is supplied to the control pressure working oil chamber via the port 31 of the control valve 20, the air in the oil chamber does not leak to the outside. Thus, the rise of the oil pressure in the oil chamber is considerably delayed as compared with the rise of the oil pressure in the line pressure oil chamber.

As a result, at the time of the range shift from the N range to the D range, the hydraulic pressure acting on the right end face of the land 45 of the control valve 20 becomes considerably larger than the hydraulic pressure acting on the left end face of the land 41, and the control valve The spool 21 may move to the left so that the port 32 of the 20 is opened, and a direct connection between the impeller and the turbine may be established. in this case,
Even if the duty ratio of the solenoid valve 50 is set to a small value in order to maintain the two in a non-direct connection state,
The direct connection state is unintentionally established irrespective of the duty ratio.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hydraulic control device in which the operation reliability of a supply hydraulic pressure switching means for switching a supply / discharge state of hydraulic pressure to a hydraulic operation mechanism is improved.

[0013]

Means for Solving the Problems A hydraulic system comprising a hydraulic operating mechanism, a supply hydraulic switching means for switching a supply / discharge state of hydraulic pressure to the hydraulic operating mechanism, and a control means for controlling the operation of the supply hydraulic switching means In the control device, the hydraulic control device of the present invention
Supplying hydraulic switching means for location is provided with a spool valve, the oil chamber control pressure from being formed on one end face side control means of the spool valve is supplied, the air release chamber formed on the other end side of the spool valve, It is characterized by comprising a communication hole for communicating the oil chamber and the open-to-air chamber via a flow restricting means. In the present invention
Preferably, the open-to-air chamber is provided with oil leaking from the oil chamber or
Expels air in the oil. The hydraulic actuation mechanism is
It is a clutch that can connect an input element and an output element. Good
Preferably, the spool valve is provided with a slide formed on the valve body.
The communication hole is housed in the contact hole, and the communication hole is
A formed shaft center and a half extending from the shaft center to the sliding contact hole side.
It consists of a diameter part. In this case, the flow restricting means is a spool valve
It is preferably a gap between the contact hole and the sliding contact hole. Preferably,
The supply pressure switching means has a line pressure
Oil chamber, and oil leaking or emptying from the line pressure oil chamber.
A second air release chamber where the air is released to the atmosphere, and a line pressure action chamber
A first seal portion that seals between the first chamber and the second air release chamber;
A second seal for sealing between the communication hole and the open-to-atmosphere chamber.
And a metal part is formed. Also, the first seal portion and the second seal portion
It is formed to have substantially the same width as the screw portion. More preferably, the above
The line pressure is supplied in the D range.

[0014]

When the control pressure is supplied to the oil chamber even when air is accumulated in the oil chamber of the spool valve of the supply hydraulic pressure switching means, the air in the oil chamber is released to the atmosphere via the flow restricting means and the communication hole. It is discharged to the open room. Therefore, there is no delay in the rise of the hydraulic pressure in the oil chamber due to the air accumulated in the oil chamber. In other words, the supply oil pressure switching means has high operation reliability.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A direct connection mechanism of an automatic transmission as a hydraulic control device according to one embodiment of the present invention will be described below. This direct connection mechanism has basically the same configuration as that shown in FIG. 1, and the same components as those in FIG.
Description is partially omitted.

As shown in FIGS. 3 and 4, the direct connection device as a hydraulic control device includes a damper clutch 12 as a hydraulic operating mechanism, a damper clutch control valve 120 as supply hydraulic pressure switching means, and a normal control device as a control means. An open type solenoid valve 50 is provided, and the supply / discharge state of the hydraulic pressure to / from the damper clutch 12 is switched by the control valve 20 which responds to the control pressure from the solenoid valve 50 to connect the impeller and the turbine of the torque converter 10 (more generally). Specifically, the input element and the output element of the fluid coupling are brought into a directly connected state or a non-directly connected state via the damper clutch 12.

The damper clutch control valve 120 is a spool valve and has a sliding contact hole 1 formed in a valve body 120a.
A spool 121 is slidably housed in the spool 20b. The spool 121 has lands 41 to 45, 146 and 147. The lands 146 and 147 are slidably disposed in a sleeve 148 fitted in the sliding contact hole 120b of the valve body 120a.

The spool 121 has an axial hole 121a formed along the axis thereof and an appropriate number, for example, two radial holes 121b formed at a predetermined distance x inward from the right end face of the spool when viewed in the axial direction. ing. Shaft hole 121a
Has one end opened to the control pressure action oil chamber 149 of the control valve 120. One end of each radial hole 121b communicates with the shaft hole 121a, and the other end is open to a clearance between the land 147 of the spool 121 and the sleeve 148.

Axial hole 121a and radial hole 121b
Is a spool that extends a predetermined distance x from the right end of the spool.
A communication hole is provided to allow the control pressure oil chamber 149 and the open-to-atmosphere chamber 150 formed on the right end face side of the spool 121 to communicate with each other via a flow restricting means constituted by a clearance between the sleeves. In other words, the spool 121
A portion extending over a predetermined length x forms a first seal portion that seals between the communication holes 121a and 121b and the atmosphere opening chamber 150 in cooperation with the corresponding portion of the sleeve 148.

At the substantially central portion in the axial direction of the sleeve 148, a reduced diameter portion smaller than the diameter of both ends of the sleeve 148 is formed, and an annular second air opening chamber 151 is defined between the sleeve 148 and the valve body 120a. ing. The atmosphere opening chamber 151 opens to the atmosphere via a communication hole 152 formed in the valve body 120a. In the sleeve 148, an appropriate number, for example, two communication holes 148a are formed at a position away from the left end surface of the sleeve 148 by a predetermined distance y when viewed in the axial direction, and penetrate the sleeve 148 in the radial direction. One end of the communication hole 148a is open to the second atmosphere opening chamber 151, and the other end is open to a clearance between the sleeve 148 and the spool 121.

A portion of the sleeve 148 extending a predetermined distance y from the left end surface of the sleeve 148 cooperates with a corresponding portion of the valve body 120a to form the lands 45, 14 of the spool 121.
A second seal portion that seals between the line pressure action chamber 160 and the second open-to-atmosphere chamber 151 that is defined between the six air pressure chambers is formed. The seal width x is set to a value smaller than the seal width y.

The spool 121 has a spool 12
When the land 14 is pressed against the stopper 153, the land 14
In order to prevent the end face of the land 7 from deforming and hindering the sliding, the distance of α from the right end, for example, 0.5 mm is set to the land 14.
A portion having a smaller diameter than 7 may be set. in this case,
The length of the first seal portion described above is “x−α”. Although not shown, in connection with the direct coupling mechanism, the hydraulic circuit of the automatic transmission includes a pressure regulating valve for regulating the pressure oil discharged from the oil pump to a line pressure, and a line from the pressure regulating valve. A torque converter control valve for adjusting the pressure to a torque converter pressure, and a manual valve that is manually operated by a driver and interlocks with a select lever that takes a D, N, R, or P range are provided. The input side of the manual valve is connected to the pressure regulating valve, and the output side is connected to the port 51 of the solenoid valve 50. When the select lever is in the D range, the input side and the output side are connected to each other. Is supplied with line pressure from a pressure regulating valve. or,
The port 34 of the damper clutch control valve 120 is connected to the torque converter control valve, and the port 34 is supplied with torque converter pressure.

In FIGS. 3 and 4, reference numeral 153 denotes a stopper pin having both ends embedded in the valve body 120a. The stopper pin 153 regulates the rightward movement of the spool 121. Also, the sleeve 148
Regulates to move to the right by hydraulic pressure.
In FIG. 3, reference numerals 71 to 80 indicate oil passages. Hereinafter, FIG.
The operation of the direct connection mechanism shown in FIG. 4 will be described.

When the select lever is in the N range, for example, no line pressure is supplied from the oil passage 71 to the port 51 of the solenoid valve 50, and therefore, the damper clutch control valve 120 is controlled via the solenoid valve 50 and the oil passage 73. No line pressure is supplied to the port 31. Therefore, the spool 121 of the control valve 120 assumes the right limit position shown in FIG. Then, the torque converter pressure from the torque converter control valve flows into the oil chamber defined between the lands 42 and 43 of the control valve 120 via the oil passage 79 and the port 34 of the control valve 120, The oil flows from the oil chamber into the torque converter 10 through the port 38 of the control valve 120, the oil passage 77, and the port 13 of the torque converter 10.
This torque converter pressure acts in a direction to separate the damper clutch 12 from the front cover 11, so that the connection between the impeller and the turbine is cut off, and the impeller and the turbine are not directly connected.

The torque converter pressure flows out of the Turkish converter 10 via the port 14 of the torque converter 10 and then through the oil passage 76 and the port 39 of the damper clutch control valve 120 between the lands 43, 44 of the control valve 120. And is supplied from the oil chamber to various lubricating parts of the automatic transmission via the port 35, the oil passage 80 and the oil cooler 60.

Thereafter, the select lever is moved from N range to D
When manually operated in the range, the line pressure from the pressure regulating valve
The oil is supplied to a port 51 of the solenoid valve 50 through an oil passage 71, and further, through a port 52, an oil passage 72, and a port 36 of the damper clutch control valve 120, the land 45 of the control valve 120, It is fed to the line pressure oil chamber defined between 146. At this time, if the energization to the excitation coil 55 of the normally open solenoid valve 50 is stopped under the control of a transmission controller (not shown), the ports 51 and 53 of the solenoid valve 50 are always in communication with each other. Oil passage 7 communicating with 53
3 and the control valve 1 through the port 31 of the control valve 120.
The line pressure is also supplied to the control pressure operation oil chamber 149 of 20.

One of the line pressure control oil chamber 149 and the control pressure oil chamber 149 of the direct connection mechanism may be used for some reason, such as when the vehicle equipped with the automatic transmission has not been operated for a long period of time or immediately after the automatic transmission has been assembled. Air may accumulate on both sides. In such a situation, when the N → D range shift is performed as described above, in the conventional device, the normally open solenoid valve 50 is de-energized (strictly speaking, the solenoid valve duty ratio becomes the value D1 in FIG. 6). The spool moves to the left even if
The impeller of the torque converter 10 and the turbine may be unintentionally directly connected via the damper clutch 12.

On the other hand, in the direct connection mechanism of this embodiment,
When the N → D range shift is performed in a state where air is accumulated in both the line pressure oil chamber and the control pressure oil chamber 149, if the solenoid valve 50 is deenergized, the line pressure to both oil chambers is reduced. The oil pressure rises equally in both oil chambers due to the supply, so that the spool does not move leftward which may cause an undesired direct connection state.

The reason for this is that, in the direct connection mechanism of the present embodiment, the line pressure working oil chamber is provided with a clearance between the sleeve and the valve body on the left end side of the sleeve (the second seal portion) and a clearance between the sleeve land 146 (the third seal portion). The control pressure working oil chamber 149 communicates with the second atmosphere opening chamber 151 via the seal portion) and the clearance (first seal portion) between the communication holes 121a and 121b and the spool / sleeve on the right end side of the spool. This is because it communicates with the open-to-atmosphere chamber 150. That is, the air accumulated in the line pressure oil chamber leaks to the second atmosphere opening chamber 151 through the second seal portion and the third seal portion by the supply of the line pressure to the oil pressure chamber, and the control pressure oil The air accumulated in the chamber 149 is supplied to the communication chambers 121a, 1b by line pressure supply to the oil chamber.
Leakage into the open-to-atmosphere chamber 150 via the first seal portion 21b and the first seal portion prevents the rise of hydraulic pressure in both oil chambers from being hindered.

In addition, since the sealing effect of the first sealing portion is set to be the same as the sealing effect (air leakage resistance) of the second sealing portion and the third sealing portion, the air leaking from both sealing portions is set. , The amount of oil is the same, and the rise of the oil pressure in the line pressure oil chamber and the control pressure oil chamber 149 becomes equal. Therefore, the damper clutch control valve 12
The zero spool 121 does not move to the left while keeping the right limit position shown in FIG. 3, so that the connection between the impeller and the turbine of the torque converter 10 is cut off, and the impeller and the turbine are maintained in a non-direct connection state. .

Thereafter, when the energization of the excitation coil 55 of the solenoid valve 50 is duty-controlled while the select lever is in the D range, when the excitation coil 55 is excited, the port 51 and the port 53 of the solenoid valve 50 are connected. The communication is blocked by the valve element 58. Therefore, the ports 51 and 53 of the solenoid valve 50 and the damper clutch control valve 1
The control oil pressure supplied to the control pressure oil chamber of the control valve 120 through the port 31 of the control valve 20 decreases as the duty ratio increases, and the spool 121 moves to the left to control the control valve 12.
0 port 32 is opened. The line pressure supplied to the port 32 via the oil passage 74 is applied to the torque converter 10 via the port 37 of the control valve 120, the oil passage 75, the ports 40 and 39, the oil passage 76, and the port 14 of the torque converter 10. And acts in a direction to press the damper clutch 12 against the front cover 11. That is, an apply pressure is applied to the damper clutch 12. Here, since the oil passage 74 is connected to the above-described pressure regulating valve,
The line pressure is always supplied to the port 32 regardless of the position of the select lever.

As shown in FIG. 6, the apply pressure increases as the duty ratio of the solenoid valve 50 increases. When the duty ratio reaches 100%, the spool 121 of the control valve 120 assumes the left limit position shown in FIG. 5, and the impeller and the turbine of the torque converter 10 are completely directly connected via the damper clutch 12. The portion between the front cover and the damper clutch in the torque converter 10 is released to the atmosphere via the port 13 of the torque converter 10, the oil passage 77, the ports 38 and 33 of the damper clutch control valve 120, and the oil passage 78. Be released. The torque converter pressure flowing into the control valve 120 from the port 34 is discharged from the port 35 through the oil cooler 60.

In the above embodiment, the oil passage 72 communicates with the oil passage 71 via the port 52 which communicates with the port 51. However, the oil passage 71 branches and one of the oil passages 71 communicates with the port 51, and the other communicates with the port 36. The same holds true for a communicating structure. Further, in the embodiment, the case where the present invention is applied to the direct coupling mechanism of the automatic transmission has been described. However, the present invention provides a hydraulic operating mechanism which responds to the hydraulic pressure supplied and discharged by the supply hydraulic pressure switching means controlled by the control means. The present invention can be applied to various hydraulic control devices provided with

[0034]

As described above, the hydraulic operating mechanism, the supply hydraulic pressure switching means for switching the supply / discharge state of the hydraulic pressure to the hydraulic operating mechanism, and the control means for controlling the operation of the supply hydraulic switching means are provided. In the hydraulic control device, the supply hydraulic pressure switching means of the present invention is formed on a spool valve, an oil chamber formed on one end face side of the spool valve and supplied with control pressure from the control means, and formed on the other end face side of the spool valve. And a communication hole for communicating the oil chamber and the air opening chamber via the flow restricting means, the operation reliability of the supply oil pressure switching means of the hydraulic control device can be improved, and for example, the oil pressure is accumulated. Malfunction of the spool valve due to air can be prevented.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing a conventional direct-coupled mechanism with its spool at a right limit position.

FIG. 2 shows a state in which the spool is at a left limit position.
FIG. 2 is a hydraulic circuit diagram of the direct connection mechanism of FIG. 1.

FIG. 3 is a hydraulic circuit diagram showing the direct coupling mechanism according to one embodiment of the present invention in a state where the spool is at the right limit position.

FIG. 4 is an enlarged view of a damper clutch control valve of the direct coupling mechanism of FIG. 3;

FIG. 5 shows a state in which the spool is at a left limit position.
FIG. 4 is a hydraulic circuit diagram of the direct connection mechanism of FIG. 3.

FIG. 6 shows the duty ratio of the solenoid valve of the direct connection mechanism of FIG.
It is a graph which shows an application pressure and release pressure characteristic.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Torque converter 12 Damper clutch (hydraulic operation mechanism) 20, 120 Damper clutch control valve (supply oil pressure switching means) 21, 121 Spool 31-40, 51-54 Port 41-46, 146, 147 Land 47, 148 Sleeve 50 Solenoid Valve (control means) 55 Exciting coil 60 Oil cooler 71-80 Oil passage 120a Valve body 120b Sliding contact hole 121a Shaft hole 121b Radial hole 149 Control pressure oil chamber 150 Air open chamber 151 Second air open chamber 160 Line pressure action Chamber x, y Seal width

──────────────────────────────────────────────────続 き Continuation of the front page (72) Yoshio Hasegawa, Inventor Mitsubishi Motors Corporation, 33-3-8, Shiba, Minato-ku, Tokyo (56) References JP-A-6-193725 (JP, A) Hei 2-504664 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 61/14

Claims (3)

(57) [Claims] 1. A hydraulic control apparatus comprising: a hydraulic operating mechanism; supply hydraulic switching means for switching a supply / discharge state of hydraulic pressure to the hydraulic operating mechanism; and control means for controlling operation of the supply hydraulic switching means. The supply oil pressure switching means includes a spool valve, an oil chamber formed on one end face side of the spool valve, and supplied with control pressure from the control means, and an open-to-atmosphere formed on the other end face side of the spool valve. A hydraulic control device, comprising: a chamber; and a communication hole for communicating the oil chamber and the open-to-air chamber via a flow restricting means. 2. The spool valve is housed in a sliding contact hole formed in a valve body, and the communication hole has a shaft portion formed in an axis of the spool valve and a sliding portion formed from the shaft portion. 2. A radial portion extending toward a contact hole.
Hydraulic control device. 3. The supply oil pressure switching means includes a line pressure oil chamber on which a line pressure acts, a second air opening chamber for releasing oil or air leaking from the line pressure oil chamber to the atmosphere, A first seal portion for sealing between the line pressure action chamber and the second air release chamber; and a second seal portion for sealing between the communication hole and the air release chamber, wherein the first seal portion is provided. The hydraulic control device according to claim 1, wherein the portion and the second seal portion are formed to have substantially the same width.