JP2003322272A - Pressure control valve assembly and method for operating pressure control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solenoid valve-operated spool type pressure control valve for controlling a flow by a signal output, i.e., a desired pressure in a control port. <P>SOLUTION: This solenoid valve-operated spool type pressure control valve 10 controls the flow between a pressure inlet port 24 and a valve chest 14 connected to a control signal outlet port 22. A spool 30 controls the flow fed from the valve chest 14 to an exhaust port 28. A solenoid armature 52 is connected to an operation rod 50 urged by bringing an end thereof into contact with an end part of the spool 30. An adjustment screw is provided in a magnetic pole 56, and makes adjustment to limit the stroke of the armature 52 and the operation rod 50 when the exhaust port 28 is completely opened at the maximum coil current, and the urging force of the pressure applied to the spool approaches zero. When a coil 44 is demagnetized, the operation rod 50 is not brought into impact-contact with the spool 30 to remove disturbance of the pressure. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to a control outlet port by draining fluid from a pressurized fluid source, particularly a hydraulic source, to an exhaust port connected to an oil tank or reservoir for the system to be controlled. Control valve of the type for controlling the pressure signal to.

[0002]

2. Description of the Prior Art Valves of this type are used in the field of the automobile industry.
It is widely used to control fluid pressure for hydraulically driven steering systems and to control shift actuators in automatic power transmissions.

Such valves are generally spool valves of the type actuated by an electromagnetic solenoid with a movable armature, which valve is connected from the inlet of the pressurized fluid to an outlet port for control signals. The spool is moved by a predetermined amount in order to control the flow to the valve chamber or the flow from the valve chamber to the exhaust outlet port.

Solenoid actuated spool valves of the type described above are pressure balanced spools, or the relatively small desired biasing force that moves the spool in a direction such that pressure acting on the spool reduces pressure on the outlet port. And a spool configured to generate. In such a pressure-biased solenoid operated spool valve, the exhaust port is opened when the valve reduces the flow rate from the high pressure inlet port to the valve chamber.
It has been found that it approaches zero and that the biasing force due to the pressure on the valve spool is also zero. In one design, this biasing force allows precise control of spool movement in response to electrical excitation because the spool and actuator maintain contact with the armature.

However, the more the solenoid excites, the more the spool will reduce the pressure at the control signal output and move to the open port position. Then, the urging force applied to the spool approaches zero, and the movement of the spool is stopped even if the armature continues its movement.

While the solenoid excitation is increasing, the armature can move away from the spool and its actuating member, resulting in a lash between the armature and the spool. When the armature and the spool are deenergized at a considerable speed, the armature receives a moment and collides with the spool. This causes transients or disturbances in the hydraulic system to be controlled.

Therefore, the pressure in the pressure control port and the valve chamber becomes zero when the exhaust port is opened, and the urging force of the pressure acting on the spool disappears, so that the lash (collision) that occurs in the solenoid operated spool valve is prevented. It is desirable to provide a method or means for doing so.

It is also desirable to provide a solenoid actuated pressure control valve in which the armature impinges on the spool at zero control pressure so that the system to be controlled is not disturbed.

Furthermore, it would be desirable to provide such a pressure control valve that is relatively inexpensive to manufacture and easy to assemble and calibrate. It is desirable that such a solenoid operated pressure control valve be suitable for driving at a low voltage and a low current for an automobile.

In FIG. 3, a graph in which the output port pressure (P2) of the control signal is plotted in relation to the coil exciting current is shown as a conventional example. This pressure (P2) approaches zero at high levels of solenoid coil current. In the graph of the conventional example shown in FIG. 3, it can be seen that when the current decreases from the maximum excitation level, the control pressure (P2) is disturbed or oscillated due to pressure runaway near the zero current level.

[0011]

SUMMARY OF THE INVENTION The present invention provides a signal output,
That is, it is an object to provide a solenoid operated spool type pressure control valve for controlling a flow at a desired pressure at a control port. The control port is adapted to connect to a hydraulic system to be controlled from a valve chamber connected to a source of pressurized fluid, and the valve chamber is connected to an exhaust outlet port via which the pump reservoir is connected. The flow is controlled by the spool for discharge to.

[0012]

In order to achieve the above object, the present invention has the constitution described in each claim. According to the configuration of the present invention, (a) the valve hole, the inlet port, the control outlet port, and the exhaust port are spaced apart along the valve hole, and these plural ports communicate with the valve hole. And (b) a valve member disposed in the valve hole and slidable to control the pressure between the inlet port and the control outlet port and between the outlet port and the exhaust port. (C) solenoid actuation means disposed on the valve body and including a coil and an armature movable in response to electrical excitation of the coil to close an actuation air gap with respect to a magnetic pole; d) with the valve member so that it is movable with the armature and when the armature closes the air gap, the valve member opens the exhaust port and releases the pressure of the outlet port as exhaust pressure. An actuator member movable by touch, and (e) an adjustable stopper operable to limit the movement of the armature and not to close the operating air gap when the pressure of the outlet port reaches the pressure of the exhaust port. It is characterized by having and.

Further, the valve member controls the first annular valve land for controlling the flow from the inlet port to the valve chamber and the flow from the valve chamber to the exhaust outlet port which is always connected to the valve chamber. A valve spool having a second annular valve land. The spool has a second valve land for the exhaust port having a larger diameter than the first land to provide a larger annular area exposed to the valve chamber, so that the pressure in the valve chamber causes the pressure in the exhaust port to increase. Energize the spool in the opening and closing direction.

The armature and the magnetic pole have complementary surfaces that form a conical tapered surface for the working air gap. The solenoid actuating member is slidable by being guided by a pair of axially spaced bearings, and the valve member is axially spaced from an annular exhaust valve land for controlling the flow of the exhaust outlet port. And an annular inlet metering land for controlling the flow of the inlet port.

According to another configuration, the valve member includes an annular exhaust valve land for controlling the flow to the exhaust outlet port, and an annular inlet valve land for controlling the flow in the inlet port, The inlet valve land has a smaller diameter than the exhaust valve land, which provides a force to bias the fluid pressure in the direction of opening the exhaust outlet port.

The solenoid armature has an actuation rod connected thereto, the actuation rod contacting the spool end, the armature and actuation rod in a direction to close the exhaust boat and open the inlet port. It is spring biased to move the spool, which provides maximum pressure to the control pressure chamber and control signal outlet port. When driven, the armature can be drawn in a manner that closes the working gap with the magnetic poles and provides hydraulic pressure to move the spool in a direction that closes the inlet port and opens the exhaust port.

The maximum travel of the solenoid and actuation rod is limited by an adjustable stop pin on the poles to prevent the armature from closing the actuation air gap completely and the exhaust port is fully open. At this time, the armature is prevented from moving away from the spool so that the hydraulic biasing force applied to the spool becomes zero.

[0018]

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, a valve assembly 10 of the present invention includes a valve body 12 having a valve chamber 14. The valve chamber communicates with the first valve hole 16 at the upper end and communicates with the second valve hole 18 at the lower end having a small diameter.
The valve body 12 has an upper portion including an annular flux collector, or pole segment 20, which is attached to the upper end of the valve body by any suitable means such as press fit, welding, adhesive, or threaded connections.

The valve body 12 has at least one, and preferably a plurality of control pressure outlet ports 22 formed therein. This outlet port communicates with the valve chamber 14. The valve body 12 also has a plurality of inlet ports 24 axially spaced from the outlet port 22. These inlet ports 24 can be connected to a pressurized fluid source (not shown) such as a hydraulic pump, for example. As shown in FIG. 1, each inlet port 24 preferably forms a feathering notch 26 on one side of the port to sense the reduced pressure as each port is closed, as described below. A third set of ports is axially spaced from the inlet port 24 on either side of the valve chamber 14. In addition, a plurality of ports 28 are provided at the pump inlet (not shown) or oil sump (not shown).
Can be connected to, and thus this port is considered the exhaust port.

A valve spool 30 is slidably disposed in the valve chamber 14 and has an upper annular valve land or surface 32 which fits within the valve bore 16 to limit fluid leakage. While being able to slide. Further, the valve spool 30 has a lower inlet valve land 34, and is fitted into the valve hole 16 so as to be slidable while minimizing fluid leakage therebetween.

The valve lands 34, 32 have a suitable axial length, with land 32 covering the exhaust port and land 34 covering the inlet port 24. It will be appreciated that the lower annular axial surface 36 of the land 32 is axially disposed on the spool 30 so as to open and close the plurality of ports 28 with axially limited relative movement. Similarly, land 34
The upper axial surface 38 of is arranged to open and close the inlet port 24 including the notch 26.

The preferred embodiment of the present invention for use in motor vehicles operates with low pressure control in the range of 0 to 130 PSIG (0 to 900 kPa). Sufficient spool stroke is 0.014 to 0.017 inches (0.35 to 0.
It has been found to be sufficient if it can be moved within the range of (43 mm). However, the present invention is not limited to the pressure range and stroke arrangement described above, and
Other valves may be used, depending on the need for fluid operated valves.

The magnetic flux collector 20 has an annular hub 43 extending upward from the lower magnetic flux collector, on which one end of the coil hobbin 40 is received and fits. The bobbin 40 has a coil 44 wound around the bobbin 40, and both ends (not shown) of the coil extend to the outside of the coil for electrical connection with the outside by a known method.

The outer casing, or shell 42, is
This shell 42 is received over the coil 44.
The lower end of is attached to and fitted into the flux collector 20, for example press fit, crimp, crimp,
Alternatively, it may be retained on the annular shoulder 46 by any suitable means such as adhesive. The shell 42 is formed of a magnetically permeable material to create a magnetic flux loop around the coil 44.

The flux collector 20 has a lower bearing 48 which slidably receives one end of an actuation rod or actuator member 50. The lower end of the actuator member 50 is in contact with the upper end of the spool 30. An annular armature 52 is mounted around the actuation rod 50, and the upper end of the actuation rod extends through the armature and the second bearing. A second bearing is provided in the upper pole piece 56, the pole piece
It is attached to the upper end of the casing 42 so that the lower end of the casing 42 is connected to the magnetic flux collector 20.

At the lower end of the spool 30 is placed the upper end of a spring 58, while the lower end of the spring 58 is retained within the bore 18 by a suitable plug fixed to the lower end of the body 12. A vent port 62 is formed through the plug 60 to vent the lower end of the spool to atmosphere or ambient pressure.

The upper end of armature 52 slopes annularly, preferably conically, to form an operating air gap indicated by reference numeral 64 with respect to upper pole piece 56. The cap or plug 66 is received on the upper end of the pole piece 56 with a threaded fit. The plug 66 has a recess 68 formed on the bottom side thereof, and receives the spring 70 therein. The spring 70 is fitted in a bush 71 provided on the upper end of the actuator member 50. The adjustment pin 72 (adjustment stopper) is engaged with the plug 66 by screw fitting and can be adjusted from the outside. A pin 72 extends downward through the plug 66, the lower end of which abuts the upper end of the rod 50 and is adjustably positioned to limit upward movement of the rod 50 and armature 52. .

In this operation, the spool is in the valve chamber 14
Is urged upward by the pressure at. The control pressure outlet port 22 is operated by the differential pressure area between the lower surface of the land 32 and the upper surface of the land 34. The upper end of the spool is in contact with the lower end of the operating rod 50.

In operation when coil 44 is de-energized, spring 70 causes actuation rod 50 and armature 52 to be pressed downward against spool 30. With the coil fully energized, the current through the coil is maximized and the armature 52 is pulled upwards until the upper end of the actuation rod 50 abuts the lower end of the pin 72, minimizing the air gap. . Pin 72
Is adjusted during calibration so that the air gap 64 is not completely closed, and prohibits further armature movement, and the lower end of the actuation rod 50 causes the spool 3 to move.
Do not leave the top of 0.

In FIG. 2, a graph showing the maximum current flow in the coil 44 is shown, and the pressure in the valve chamber 14 and the control pressure (P2) in the outlet port 22 are zero. When the pressure in the valve chamber 14 is zero, the upward biasing force due to the hydraulic pressure of the spool does not act. Therefore, the calibration of the pin 72 prevents the armature and actuation rod from being pulled further upward by the magnetic forces acting on the armature 52. Also,
The lower end of the operating rod is kept in contact with the upper end of the spool. The pressure trajectory for the valve of the present invention is shown in FIG. 2, in which the valve chamber 14 and outlet port 22 for control pressure, as shown in the pressure plot in conventional valve operation shown in FIG. No pressure transients.

Thus, the present invention provides a unique and novel solenoid actuated pressure control valve that limits the upward movement of the armature when operating at maximum current and reduces lash between the actuation rod and spool. To prevent. It also eliminates shocking contact of the actuation rod with the spool when the coil is de-energized, preventing transients in the outlet port for the control pressure transmitted to the system to be controlled.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments described herein, but includes various changes and modifications and is covered by the appended claims. The above description is included without departing from the scope or the technical idea thereof.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of the valve assembly of the present invention taken along the axis of symmetry of the spool and armature.

FIG. 2 is a table showing an outlet pressure (P2) for a control signal with respect to a current when a coil is excited.

FIG. 3 is a chart similar to FIG. 2 in a valve assembly in a conventional example.

[Explanation of symbols]

10 valve assembly 12 valve body 14 valve chamber 16,18 valve hole 20 magnetic flux collector 22 Exit port 24 entrance ports 28 Discharge port 30 valve spool 32, 34 valve land 44 coils 50 working rod 52 Armature 56 pole pieces 72 Adjustment pin

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3H002 BB06 BE01                 3H106 DA02 DA23 DB02 DB12 DB23                       DB32 DC09 DD09 EE04 EE16                       EE19 EE20 EE33 GA23 GC07                       KK02 KK17

Claims (12)

[Claims] (A) A valve hole is provided, an inlet port, a control outlet port, and an exhaust port are spaced apart along the valve hole, and a plurality of these ports communicate with the valve hole. A valve body, and (b) a valve member disposed in the valve hole and slidable for controlling the pressure between the inlet port and the control outlet port and between the outlet port and the exhaust port, c) solenoid actuation means disposed in the valve body and including a coil and an armature movable in response to electrical excitation of the coil to close an actuation air gap with respect to the magnetic poles; Is movable with the armature and is in contact with the valve member such that when the armature closes the air gap, the valve member opens the exhaust port and releases the outlet port pressure as exhaust pressure. A movable actuator member; and (e) an adjustment stopper that limits movement of the armature and is operable so that the operating air gap does not close when the pressure at the outlet port reaches the exhaust port pressure. An electrically actuated pressure control valve assembly, comprising: 2. The pressure control valve assembly of claim 1, wherein the actuating member comprises an elongate member received through the armature. 3. The pressure control valve assembly according to claim 1, wherein the armature has an annular shape into which the actuating member is fitted and inserted. 4. The pressure control valve assembly according to claim 1, wherein the valve member comprises a spool having first and second axially spaced valve lands. 5. The pressure control valve assembly according to claim 1, wherein the adjustment stopper includes a member that is screw-fitted to the magnetic pole. 6. The pressure control valve assembly according to claim 1, wherein the adjustment stopper includes an extension member threadably fitted to the magnetic pole and contacting an end portion in the vicinity of the operating rod. 7. The armature and magnetic pole have complementary surfaces that form a conical tapered surface for the working air gap. Pressure control valve assembly. 8. The pressure control valve assembly according to claim 1, wherein the actuating member is slidable by being guided by a pair of axially spaced bearings. 9. The valve member has an annular exhaust valve land for controlling the flow of the exhaust outlet port and an annular inlet metering land for axially spaced control of the inlet port flow. The pressure control valve assembly of claim 1, wherein: 10. The valve member includes an annular exhaust valve land for controlling flow to an exhaust outlet port and an annular inlet valve land for controlling flow at the inlet port, the inlet valve land comprising: The pressure control valve assembly according to claim 1, wherein the pressure control valve assembly has a diameter smaller than that of the exhaust valve land, thereby providing a force for biasing fluid pressure in a direction of opening the exhaust outlet port. 11. A method of operating a solenoid pressure control valve having a fluid pressure inlet port, a control pressure outlet port, and an exhaust port, the method comprising: (a) communicating with the plurality of ports through valve holes. Place the valve spool to
Arranging a solenoid having a coil and a movable armature adjacent to the end of the spool, (c) connecting an actuator member to the armature and controlling the spool using the actuator member, (d)
A magnetic pole piece having a coil is arranged to form an operating air gap in the armature, (e) an adjusting stopper is arranged adjacent to the actuator member, and when the coil operates at maximum current, A method comprising adjusting the amount of movement of the actuator member to limit closure and movement of the armature. 12. The step of disposing the adjusting stopper includes screwing a pin onto the pole piece.
The method described in 1.