JP2002357281A - Electromagnetic control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic control valve capable of reducing the amount of leakage of oil at low temperature with a low cost and performing the assembling of a solenoid easily. SOLUTION: The electromagnetic control valve 1 is composed of a solenoid 10, control valve 30 and seat member 21. The seat member 21 is formed with a bleeding hole 211, constituting a bleeding pressure control dhamber 23 with a spool 32 in between. The control valve 30 is provided with a 2nd supply port 39, control orifice 33 and 2nd drain port 40 in the vicinity of seat member 21. The seat member 21 is provided with a 2nd orifice 214 having a diameter smaller than that of the control orifice 33 to make it communicate with the bleeding pressure control chamber 23. moreover, inside the solenoid 10, provided is an inner circular ring part 14b of a yoke 14 having a prescribed clearance and insertion length with respect to a stator core 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pressure control chamber provided between a spool and a solenoid, a second supply port including a control orifice for adjusting oil flowing into the pressure control chamber, and an oil in the pressure control chamber. The present invention relates to an electromagnetic control valve having a valve chamber formed of two ports of a second drain port for discharging oil, and configured to reduce a leak amount of oil discharged from the pressure control chamber.

[0002]

2. Description of the Related Art In recent years, in a hydraulic circuit of an automatic transmission for automobiles, a two-port current proportional solenoid valve (so-called bleed type) for adjusting a leak flow rate from a seat to adjust a pressure between a control orifice and a seat. (A current proportional solenoid valve).

An electromagnetic valve of this type has a stator core and a moving core that can slide with respect to the stator core by energizing the coil. A bleed valve is disposed at the tip of the moving core, and abuts a bleed valve seat of a seat member. The energization of the coil moves the moving core, opens and closes the bleed hole, and changes the leakage flow from the seat to adjust the oil pressure in the pressure control chamber after the control orifice.

[0004]

However, in this type of current proportional solenoid valve, when the seat portion is fully opened in order to reduce the pressure in the pressure control chamber, the valve passes through the control orifice, so that the drain is not drained. There has been a problem that the leak amount of the oil discharged from the port is large, the load on the hydraulic pump for supplying the hydraulic pressure is increased, and the fuel efficiency is deteriorated. Therefore, since the current proportional solenoid valve cannot be used in a large number in one system as it is, the control orifice itself is formed to have a small diameter to reduce the leak amount when the seat portion is fully opened, or A method using a current proportional solenoid valve of a spool valve type having a relatively small leak flow rate has been adopted.

However, when the control orifice is formed to have a small diameter, although the amount of oil leakage can be reduced, the problem still remains that the oil flow is alienated and the hydraulic pressure response is deteriorated, especially at low temperatures. Was.

Further, when a current proportional solenoid valve of a spool valve type is used, there remains a problem that the cost is high.

Further, in this type of electromagnetic control valve, a moving core slidable by energization of a coil in the solenoid portion is fitted inside the stator core. At this time, the moving core is configured to slide within the stator core with a small clearance in order to improve the efficiency of the electromagnetic attraction force. However, when an excessive axial force or stress is applied to the stator core in the bending direction when assembling the solenoid, the stator core may be deformed, and the slidability of the moving core may be impaired.

An object of the present invention is to solve the above-mentioned problems, and a first object of the present invention is to provide an electromagnetic control valve which can be formed at a low cost and which can reduce the amount of leak without alienating the flow of oil at low temperatures. A second object of the present invention is to provide an electromagnetic control valve which can be assembled without imposing an excessive load on a stator core and without impairing the slidability of a moving core, and which can improve the efficiency of magnetic attraction force. That is.

[0009]

According to the first aspect of the present invention, an electromagnetic control valve according to the present invention is slidable by a solenoid and a hydraulic pressure adjusted by the operation of the solenoid. A seat member having an oil passage that can be opened and closed by actuation of a solenoid, and a pressure control chamber between the seat member and the spool, and an amount of oil leakage from the pressure control chamber. In the electromagnetic control valve configured to be able to reduce, the spool and the pressure control chamber between the control orifice and the pressure control chamber with the spool in contact with the seat member, that is, with the oil pressure in the pressure control chamber reduced to a minimum. A second orifice portion having a smaller diameter than the control orifice formed by the seat member is formed.

When the oil passage of the seat member is closed by the operation of the solenoid, the pressure control chamber is filled with oil supplied from the control orifice, whereby the pressure becomes equal to the hydraulic pressure supplied to the control orifice. Can be moved.

When current is applied to the solenoid to release the oil passage of the seat member, oil in the pressure control chamber is gradually discharged from the oil passage to the second drain port, and the pressure in the pressure control chamber decreases. . As the pressure in the pressure control chamber decreases, the spool moves to the sheet member side.When the spool reaches a position where the spool comes into contact with the sheet member, the spool and the sheet member provide a space between the control orifice and the pressure control chamber. Due to the formation of the two orifices, the oil enters the pressure control chamber from the control orifice through the second orifice, and is discharged through the oil passage of the seat member to the second drain port. Therefore, when the oil passage of the seat member is fully opened, the amount of oil leaked from the second drain port is reduced because it passes through the small-diameter second orifice. Since the configuration having the chamber can be formed at low cost, it is possible to provide an inexpensive electromagnetic control valve with a small amount of leakage.

According to the second aspect of the present invention, in the control orifice, that is, in the electromagnetic control valve in which the second supply port is provided near the seat member, the second orifice is formed with a slit in the seat member. Since the pressure control chamber is provided so as to be connected to the control orifice, the second orifice can be formed only by forming a small-diameter slit in the sheet member. In addition, if a mold such as a press for sintering the sheet member is used, the slit shape can be controlled by the size of the mold, so that the leak flow rate can be easily controlled and the configuration can be made inexpensive.

Further, according to the third aspect of the present invention, in the control orifice, that is, in the electromagnetic control valve in which the second supply port is provided at a position separated from the seat member, the spool is disposed between the control orifice and the pressure control chamber. And a sheet member is provided between the first sheet member and the second sheet member.
It is divided and arranged in the axial direction with the sheet member. Further, a slit is formed in the second sheet member so as to face the flow path of the spool. Therefore, when the pressure of the oil in the pressure control chamber decreases and the spool moves to a position where it contacts the end surface of the second sheet member, a slit-shaped second orifice is formed between the spool and the second sheet member, When the oil passage of the first sheet member is fully opened, the oil supplied from the control orifice is discharged to the second drain port through the second orifice. Therefore, even if the second supply port is an electromagnetic control valve disposed at a position separated from the seat member, it is possible to reduce the amount of oil leaked from the second drain port.

Further, according to the present invention, there is provided a solenoid, a spool slidably disposed by hydraulic pressure adjusted by the operation of the solenoid, and a seat member having an oil passage which can be opened and closed by the operation of the solenoid. An electromagnetic control valve having a pressure control chamber between the seat member and the spool so as to reduce the amount of oil leaked from the pressure control chamber, wherein the spool is in contact with the seat member; The spool closes a part of the control orifice to form a second orifice portion having a smaller diameter than the control orifice.

When the oil passage of the seat member is closed by the operation of the solenoid, the pressure control chamber is filled with oil supplied from the control orifice, and thereby the pressure becomes equal to the hydraulic pressure supplied to the control orifice. Can be moved. At this time, the control orifice is fully opened with respect to the pressure control chamber due to the movement of the spool. Further, by applying a current to the solenoid to release the oil passage of the seat member, the oil in the pressure control chamber is gradually discharged from the oil passage to the second drain port, and the pressure in the pressure control chamber decreases. At this time, the spool is moved toward the sheet member and gradually closes the control orifice. When the spool comes into contact with the sheet member, the control orifice is partially closed by the spool, and the control orifice is formed as a small-diameter second orifice.

Accordingly, oil enters the pressure control chamber from the control orifice through the second orifice, and is further discharged through the oil passage to the second drain port. For this reason, even if the oil passage of the seat member is fully opened, the amount of oil leaked from the second drain port is reduced because it passes through the small-diameter second orifice, and in particular, the second orifice is formed. In doing so, since the sheet member is not particularly processed, an inexpensive electromagnetic control valve with a small amount of leakage can be provided.

According to the fifth aspect of the present invention, the solenoid includes:
A moving core is slidable with respect to the stator core by providing a coil, yoke, stator core, and moving core, and generating a magnetic field by energizing the coil. The yoke includes an inner annular portion that projects axially from the rear portion of the stator core and fits inside the stator core. Since the inner annular portion has a radially one-sided clearance with respect to the inner peripheral surface of the stator core, and the insertion length protruding in the axial direction is fitted with a correlation within a set numerical value, The magnetic flux flowing from the inner annular portion to the stator core can be sufficiently ensured. That is, even when the stator core is loosely fitted to the inner annular portion of the yoke when assembling the solenoid, it is possible to sufficiently secure the magnetic flux flowing from the yoke to the stator core by increasing the insertion length. .

According to the present invention, the clearance of the annular portion with respect to one side in the radial direction with respect to the inner peripheral surface of the stator and the insertion length with respect to the axial direction are such that the clearance on one side is 0.05 to 0.25 mm. In the range of about 1:
Since the correlation is shown so as to be in the range of 40 to 60, a sufficient magnetic flux can be secured as is clear from the data based on the experimental results.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The electromagnetic control valve according to the embodiment is, for example, a solenoid valve applied to an automatic transmission of an automobile as an example, but is not limited thereto.

As shown in FIG. 1, the electromagnetic control valve 1 according to the first embodiment has a yoke 14, a stator core 11, and a moving core 12 slidable along the inner diameter of the stator core 11. A solenoid member 10 having a hollow coil 13 that generates a vibration, a sheet member 21 arranged so as to be able to abut on the moving tip side (left side in FIG. 1) of the moving core 12, A control valve 30 having a spool 32 disposed in the sleeve 31 and slidable by hydraulic pressure on the distal end side.

The stator core 11 is formed in a cylindrical shape with a hollow inside, and a moving core 12 is slidably disposed inside. A small-diameter projecting bleed valve body 121 is formed at the tip end (spool side) of the moving core 12, and is formed so as to be able to abut a bleed valve seat of a seat member 21 described later. The coil 13 is a stator core 1
1 and fitted inside the yoke 14.

The yoke 14 has an outer annular portion 14a and an inner annular portion 14b, and is formed in a double annular shape.
a and the inner ring portion 14b are connected to each other by a flange portion 14c at a rear portion of the yoke 14. As shown in FIG.
The inner annular portion 14b is fitted to the inner peripheral surface 11a of the stator core 11 on one side thereof with a clearance H (about 0.1 to 0.2 mm) which is looser than normal fitting, and a rear portion of the inner annular portion 14b is provided. The second stator 11 b is formed to protrude from the flange portion 14 c so as to be inserted into the second stator 11 b with a longer length L (about 6 to 8 mm) than usual in the axial direction. The clearance on one side in the radial direction between the inner peripheral surface 11a of the stator core 11 and the inner annular portion 14b of the yoke 14 and the length of the inner annular portion 14b inserted into the second stator 11b of the stator core 11 flow from the yoke 14. As shown in the graph of FIG. 14 showing experimental data, for example, the clearance H on one side is 0.05 to 0.25 mm, as shown in the graph of FIG.
When the clearance H on one side is 0.1 mm, the insertion length L of the inner annular portion 14b is about 6 mm, and when the clearance H on one side is 0.2 mm, the inner annular portion 14b
Is about 8.5 mm, and within this range, a predetermined magnetic flux flows between the inner annular portion 14b of the yoke 14 and the second stator 11b of the stator core 11. ing.

That is, the clearance H on one side in the radial direction of the inner annular portion 14b with respect to the inner peripheral surface of the stator core 11 with respect to the second stator 11b and the insertion length L in the axial direction are 0.05. It is set to be in a range of about 1:40 to 60 in a range of about 0.25 mm.

In the graph shown in FIG. 14, the magnetic attraction force when the moving core 12 slides is set in advance, and the magnetic flux flowing from the yoke 14 to the stator core 11 is calculated. Interpolation length L
Is shown by an experiment, and the graph shows a straight line that refracts when the one-side clearance is 0.15 mm, but may be represented as a parabola having a curve approximating this graph.

Further, when assembling the solenoid, a space is provided between the rear end surface 11c of the stator core 11 and the inner wall surface 14d of the flange portion 14c of the yoke 14 so as not to generate an axial stress on the stator core 11. And the rear end face 11c of the stator core 11 is set shorter than the distance from the stator receiving portion 14e of the yoke 14 to the inner wall surface 14d of the flange portion 14c.

Thus, when the solenoid 10 is assembled, the yoke 14 can be inserted into the stator core 11 without generating unreasonable stress (axial stress and stress in the bending direction).

The inner ring end face 141 of the yoke 14 is disposed so as to face the end face of the moving core 12 opposite to the bleed valve element 121. In addition, yoke 1
An adjuster 16 for adjusting the set load of the spring 17 is provided so as to be incorporated in the spring 4.

The stator core 11 and the moving core 1 are located between the stator core 11 and the moving core 12.
A non-magnetic spacer 18 for preventing contact with the spacer 2 is provided.

The tip side of the yoke 14 (left side in FIG. 1)
Is formed to extend from the tip of the stator core 11,
A fitting portion 311 formed at the rear end (the right side in FIG. 1) of the sleeve 31 that slidably incorporates the spool 32 is fitted inside from the outer peripheral side.

The seat member 21 is disposed so as to fit on the inner peripheral surface of the end of the sleeve 31 on the solenoid 10 side.
Is positioned and fixed by the stepped portion of the second member and the shielding plate 22. The sheet member 21 has a bleed hole 211 through which oil flows in the center of the shaft center, and the bleed hole 211.
A bleed valve seat 212 that contacts the bleed valve element 121 of the moving core 12 is formed on one end face around the spool, and a spool receiving face 213 that the end face of the spool 32 contacts is formed on the other end face. Also, the sheet member 2
The inside of one spool 32 is formed in a concave portion to form a bleed control pressure chamber 23.

Further, as shown in FIGS. 2 to 4, a small-diameter slit is formed at a part of the outer peripheral edge of the end surface of the sheet member 21 on the spool 32 side from the outer peripheral end toward the bleed control pressure chamber 23. 32 when the end surface of the second orifice 32 comes into contact with the spool receiving surface 213 of the sheet member 21.
14 are formed. One end of the second orifice 214
The control orifice 33 is connected to a second supply port 39 formed on a part of the outer peripheral surface of the sleeve 31. A plurality of drain holes 24 for discharging oil are formed in the seat member on the solenoid 10 side, and are connected to the second drain port 40 of the sleeve 31.
Therefore, the second supply port 39, the control orifice 33, the second orifice 214, the bleed control pressure chamber 23, the sheet member 21, the drain hole 24, and the second drain port 40
The port bleed valve chamber 20 is constituted.

The control valve 30 has a stepped columnar spool 32 slidably disposed in a cylindrical sleeve 31. On the inner peripheral surface of the sleeve 31, the distal end side is formed in the small diameter portion 312, and the original side is formed in the large diameter portion 313,
The large diameter portion 313 has two annular groove portions 314A and 314B.
Are formed. In one annular groove 314A, a supply port 35 for supplying hydraulic pressure is formed so as to communicate with the annular groove 314A, and in the other annular groove 314B, a drain port 37 from which hydraulic pressure is discharged has an annular shape. Groove 314B
It is formed so that it may communicate with. Also, supply port 3
An output port 36 from which the hydraulic pressure is output is arranged between the drain port 5 and the drain port 37. A second supply port 39 connected to the aforementioned control orifice 33 and a second drain port 40 connected to the one drain hole 24 are formed near the sheet member 21 on the base side (solenoid 10 side) of the outer peripheral surface. I have.

The outer peripheral base of the sleeve 31 is formed with a fitting part 311 which is fitted inside the leading end of the yoke 14 of the solenoid 10 as described above, and is connected with the leading end surface of the stator 11 and the diaphragm 19 therebetween. ing. The inner peripheral surface of the diaphragm 19 is engaged with the moving core 12 and moves together with the moving core 12, so that the oil in the bleed control pressure chamber 23 does not enter the solenoid 10.

The spool 32 is a small-diameter portion 3 of the sleeve 31.
The small diameter portion 321 slidably fitted to the sleeve 12 and the sleeve 31
And a valve part 322 which is slidably fitted in the large diameter part 313 of the valve part 322.
23 are formed. The end surface on the sheet member 21 side is formed with a contact surface 324 that comes into contact with the spool receiving surface 213 of the sheet member 21, and the small diameter portion 321 is fitted with a spring 38 for biasing the spool 32 toward the sheet member 21. A hole 325 is formed.

Further, the small-diameter portion 3 on the distal end side from the concave groove 323.
So as to penetrate the inside of the spool 32 toward 21
A feedback passage 326 is formed, and the feedback orifice 3 having a smaller diameter than the feedback passage 326 is provided near the outlet of the feedback passage 326 to the small diameter portion 321.
27 are formed.

By storing the spool 32 in the sleeve 31 formed as described above, the annular groove 314A of the sleeve 31 forms a first annular oil chamber L1 with the valve portion 322 of the spool 21, and the annular groove 314A is formed. 324B is the valve part 32
2 form a second annular oil chamber L2. Further, the concave groove 323 of the spool 32 is
13, the third annular oil chamber L3 is formed.
Further, a feedback pressure chamber L4 is formed between the large diameter portion 313 of the sleeve 31 and the small diameter portion 321 of the spool 32, and pressure is applied to move the spool 32 to the sheet member 21 side.

Next, the operation of the electromagnetic control valve 1 configured as described above will be described with reference to FIGS.

The electromagnetic control valve 1 is, as shown in FIGS.
When the coil 13 of the solenoid 10 is not energized, the moving core 12 is
The bleed valve body 121 moves to the left in the figure and the seat member 2
The bleed valve 211 is in contact with the bleed valve seat 212 to close the bleed hole 211. Since the bleed hole 211 is closed, the oil supplied from the hydraulic supply source is supplied to the second supply port 3.
9 through the control orifice 34 through the bleed control pressure chamber 2
3 is flowing. Since the oil that has flowed into the bleed control pressure chamber 23 has no place to be discharged to the outside, a pressure equivalent to the supply pressure of the second supply port 39 is generated in the bleed control pressure chamber 23 and the pressure in the bleed control pressure chamber 23 is reduced. To overcome the urging force of the spring 38,
2 is moved to the left in FIG.

On the other hand, the leftward movement of the spool 32 causes the concave groove 323 of the spool 32, that is, the third annular oil chamber L3 to move to a position where the supply port 35 and the output port 36 communicate with each other. The communication between the output port 36 and the drain port 37 is cut off. The magnitude of the force applied to the spool at this time is obtained by multiplying the cross-sectional area of the valve portion 322 of the spool 32 by the supply pressure of the bleed control pressure chamber 23, and the spring 38
And the valve portion 322 and the small diameter portion 321 of the spool 32.
It is set to be larger than the sum of the area difference of the feedback pressure chamber L4 and the area difference between the two. As a result, the oil supplied from the hydraulic supply source always flows into the clutch side in the case of, for example, an automatic transmission of an automobile.

When the coil 13 of the solenoid 10 is energized, as shown in FIGS.
Overcomes the urging force of the spring 17 and moves rightward in the figure. Then, the bleed valve element 121 of the moving core 12 moves to the right, thereby causing the seat member 21 to move.
Of the bleed control pressure chamber 2 is released.
The oil in 3 flows into the output side through the bleed hole 211 and is discharged from the drain hole 24 to the outside through the second drain port 40.

On the other hand, the spool 32 is
As the oil in 3 is discharged, the pressure for pressing the spool 32 is reduced. Therefore, the spool 32 is gradually moved rightward by the urging force of the spring 38 and the pressure of the feedback pressure chamber L4. As the spool 32 moves to the right, the third annular oil chamber L3 becomes
5 to shut off communication from the supply port 35 to the output port 36 and release the drain port 37,
By connecting the output port 36 and the drain port 37,
For example, oil supplied to a clutch in an automatic transmission of an automobile is discharged.

When the contact surface 324 of the spool 32 comes into contact with the spool receiving surface 213 of the sheet member 21, the oil supplied from the second supply port 39 flows into the second orifice 214 through the control orifice 33. 2 orifice 2
14 flows into the bleed control pressure chamber 23. Then, the gas is discharged from the bleed hole 211 to the drain hole 24 and the second drain port 40.

Therefore, the oil discharged from the second drain port 40 is discharged (leaked) through the control orifice 33, so that a large amount of oil is leaked. Since the second orifice 214 is formed in a state where the spool 32 is in contact with the end face of the sheet member 21 and the oil flowing from the second orifice 214 is discharged, the amount of leakage is reduced. Very small amounts.

Accordingly, in the electromagnetic control valve 1 of the above-described embodiment, since the slit is formed in the end surface of the seat member 21, the control valve 30 formed so that the second supply port 39 is provided near the seat member 21 is provided. It will be suitably used.

Next, a second embodiment in which the second orifice is formed in the sheet member 21 will be described. In this form,
The second supply port has a control valve configured to be spaced apart from the seat member. The connection between the solenoid and the control valve is the same as in the above-described embodiment, and is configured as shown in FIG.
In the following description, the same parts as those in the above-described embodiment, in particular, the solenoids will be denoted by the same reference numerals.

That is, the electromagnetic control valve 5 of this embodiment has a solenoid 10 and a control valve 60 in which a spool 62 is slidably housed in a sleeve 61, and is provided between the stator core 12 and the spool 62. Is provided with a sheet member 51. The second supply port 63 and the control orifice 64 are on the tip side of the sleeve 61 (left side in the figure).
And inside the spool 62, the oil flow path 6
21 is formed extending from a position facing the second supply port 63 to a contact surface 622 of the spool 62 with the sheet member 51.

The sheet member 51 is provided with a bleed control pressure chamber 53 and a bleed hole 521, and is formed between the first sheet member 52 and the spool 62. The second sheet member 54 formed in
And are formed separately. Further, a plurality of drain holes 55 are formed in the first sheet member 52 on the side opposite to the second sheet member 54.

As shown in FIG. 8, the second sheet portion 54
Along the circumferential direction, a plurality of oil through holes 541 are formed penetrating in the axial direction, of which two oil through holes 541 and 541 disposed at symmetrical positions are connected through the axis. A slit 542 is formed on the spool 62 side. The slit 542 is formed as the second orifice 542 when the spool 62 comes into contact with the end surface of the second sheet member 54.

Therefore, the oil supplied from the second supply port 63 passes through the oil passage 621 from the control orifice 64,
It flows into the bleed control pressure chamber 53 from the second orifice 542 through the oil passage holes 541 and 541.
Then, the control orifice 64 from the second supply port 63,
The two-port valve chamber 50 is constituted by a hydraulic circuit flowing through the second drain port 69 through the oil flow path 621, the second orifice 542, the bleed control pressure chamber 53, and the bleed hole 521.

On the other hand, in the sleeve 61 of the control valve 60, a supply port 65, an output port 66, and a drain port 67 are formed side by side similarly to the above-described embodiment, and a second supply port is provided in front of the supply port 65. 63 is disposed, and a second drain port 69 is disposed near the sheet member 21 so as to communicate with the one drain hole 68.

In the electromagnetic control valve 5, when the coil 13 of the solenoid 10 is not energized, the bleed valve 121 abuts the bleed valve seat 522 of the first seat member 52 to close the bleed hole 521. Therefore, the oil supplied from the hydraulic supply source and supplied to the second supply port 63 flows into the bleed control pressure chamber 63 from the control orifice 64 through the oil passage hole 541 of the second sheet member 54, and the oil is supplied to the spool 62. Moved to the left.

In this state, the spool 62 connects the supply port 65 with the output port 66 and cuts off the communication between the output port 66 and the drain port 67.

When the coil 13 of the solenoid 10 is energized, the moving core 12 moves rightward. Then, the bleed hole 521 of the first sheet member 52 is released, and the oil in the bleed pressure chamber 63 flows through the bleed hole 521 to the output side, and from the drain hole 55 to the outside through the second drain port 69. Is discharged.

On the other hand, the spool 62 is gradually moved rightward, shutting off the supply port 65, closing the communication from the supply port 65 to the output port 66, and releasing the drain port 67. Drain port 67
And communicate.

When the contact surface 622 of the spool 62 contacts the spool receiving surface 513 of the second sheet member 54, the oil supplied from the second supply port 63 is supplied to the control orifice 64.
The oil flows from the second orifice 542 through the oil passage 621 into the bleed control pressure chamber 53 through the oil passage holes 541 and 541. Then, the bleed hole 5 of the first sheet member 52 is formed.
21 to the drain hole 55 and the second drain port 69.

Therefore, also in this embodiment, the oil discharged from the second drain port 69 is supplied to the control orifice 64
A large amount of oil is leaked because the oil is discharged (leaked) through the passage. However, since the slit is formed in the second sheet member 54, the spool 62 is attached to the end face of the second sheet member 54. In contact with the second orifice 542
Is formed, and when the oil flowing in from the second orifice 542 is discharged, the leak amount becomes extremely small.

Next, an electromagnetic control valve 7 according to a third embodiment will be described. In this embodiment, the second supply port has a control valve formed so as to be disposed near the seat member, and the connection between the solenoid and the control valve is the same as in the above-described embodiment, as shown in FIGS. Is configured. In the following description, the same parts as those in the above-described embodiment, in particular, the solenoids will be denoted by the same reference numerals.

That is, the electromagnetic control valve 7 of this embodiment has a solenoid 10 and a control valve 80 in which a spool 82 is slidably housed in a sleeve 81, and is provided between the stator core 12 and the spool 82. Is provided with a sheet member 71. And the sheet member 71 is
A bleed hole 711 through which oil flows is formed at the center of the shaft center, and a bleed valve seat 712 that contacts the bleed valve element 121 of the moving core 12 is formed on one end surface around the bleed hole 711, Is formed with a spool receiving surface 713 with which the end surface of the spool 82 abuts. The inside of the sheet member 71 on the side of the spool 82 is formed in a concave portion to form a bleed control pressure chamber 73. A plurality of drain holes 74 are formed in the edge of the sheet member 71 on the solenoid 10 side.

The control valve 80 has a stepped columnar spool 82 slidably disposed in a cylindrical sleeve 81. The inner peripheral surface of the sleeve 81 is formed with a small-diameter portion 812 on the distal end side and a large-diameter portion 813 on the base portion side.
In FIG. 13, two annular grooves 814A and 814B are formed. Further, a supply port 85 to which hydraulic pressure is supplied is formed in one annular groove 814A so as to be connected to the annular groove 814A, and a drain port 88 through which hydraulic pressure is discharged is formed in the other annular groove 814B. Ring groove part 814B
It is formed so that it may communicate with. Also, supply port 8
An output port 86 from which hydraulic pressure is output is arranged between the drain port 87 and the drain port 87. A second supply port 89 and a control orifice 83 connected to the inside of the second supply port 89 are formed with a smaller diameter than the second supply port 89 near the sheet member 71 on the base side (solenoid 10 side) of the outer peripheral surface. Further, a second drain port 90 connected to the drain hole 74 is formed immediately below the sheet member 71.

The spool 82 is a small-diameter portion 3 of the sleeve 81.
12 and a small diameter portion 821 slidably fitted to the sleeve 81
And a valve portion 822 which is slidably fitted in the large-diameter portion 813.
23 are formed. The end surface on the sheet member 71 side is formed with a contact surface 824 that is in contact with the spool receiving surface 713 of the sheet member 71, and the small diameter portion 821 is fitted with a spring 88 for biasing the spool 82 toward the sheet member 71. A hole 825 is formed.

Further, the small-diameter portion 8 on the tip side from the concave groove 823.
So as to penetrate the inside of the spool 82 toward 21
A feedback passage 826 is formed, and the feedback orifice 8 having a smaller diameter than the feedback passage 826 is provided near the exit of the feedback passage 826 to the small diameter portion 321.
27 are formed to perform the same operation as the electromagnetic control valve 1 of the first embodiment.

An annular oil chamber 828 connected to the control orifice 83 is formed near the contact surface 824 of the spool 82 as shown in FIG.
24 is connected to an oil flow path 829 formed in the axial direction. The inner peripheral surface of the control orifice 83 is moved to the second orifice 83 by moving the valve portion 822 of the spool 82.
0 is formed (see FIG. 12). And the second
The two-port valve chamber 70 is constituted by a hydraulic circuit passing from the supply port 89 through the control orifice 83, the bleed control pressure chamber 73, and the bleed hole 711 to the second drain port 90.

By storing the spool 82 in the sleeve 81 formed as described above, the annular groove portion 814A of the sleeve 81 forms a first annular oil chamber L1A with the valve portion 822 of the spool 81, and the annular groove portion 814A is formed. 824B is the valve part 8
22, a second annular oil chamber L2B is formed. The concave groove 823 of the spool 82 forms the third annular oil chamber L3C with the large diameter portion 813 of the sleeve 81. Further, a feedback pressure chamber L is provided between the large diameter portion 813 of the sleeve 81 and the small diameter portion 821 of the spool 82.
4D is formed, and pressure is applied to move the spool 82 to the sheet member 71 side.

Next, the operation of the third embodiment will be described with reference to FIGS.
2 will be described.

As shown in FIG. 10, when the coil 13 of the solenoid 10 is not energized, the moving core 12 contacts the bleed valve seat 712 of the seat member 71 to close the bleed hole 711, as shown in FIG. I have. The oil supplied from the hydraulic supply source passes through the control orifice 83 from the second supply port 89 and the annular oil chamber 828 and the oil flow path 82
9 into the bleed control pressure chamber 73,
2 is moved to the left in FIG.

On the other hand, by moving the spool 82 to the left, the third annular oil chamber L3C moves to a position where the supply port 85 and the output port 86 communicate, and the supply port 85 and the output port 86 communicate with each other. The communication between the output port 86 and the drain port 87 is cut off.

When the coil of the solenoid 10 is energized, the moving core 12 moves rightward in the figure as shown in FIG. Then, the bleed valve body 121 of the moving core 12 moves rightward to release the bleed hole 711 of the seat member 71, and the oil in the bleed control pressure chamber 73 flows into the output side through the bleed hole 711. As a result, the gas is discharged from the drain hole 74 to the outside through the second drain port 90.

On the other hand, the spool 82 is gradually moved rightward. With the movement of the spool 82 to the right, the third annular oil chamber L3C shuts off the supply port 85 and turns off the supply port 8
Since the communication from the port 5 to the output port 86 is closed and the drain port 87 is released, the output port 86 and the drain port 87 are connected.

When the contact surface 824 of the spool 82 comes into contact with the spool receiving surface 713 of the sheet member 71, the control orifice 83 is closed except for a part. Control orifice 83
A part of the opening is a second orifice 830 (see FIG. 12). The oil supplied to the second supply port 89 flows from the control orifice 83 to the second orifice 830, and flows from the second orifice 830 to the bleed control pressure chamber 7.
3 is introduced. Then, the gas is discharged from the bleed hole 711 to the drain hole 74 and the second drain port 90.

As described above, the bleed control pressure chamber 73
When the bleed hole 711 is closed by the operation of the solenoid 10, the oil supplied from the control orifice 83 is filled,
As a result, the spool can be moved. Also, when a current is applied to the solenoid 10 and the bleed hole 71
By releasing 1, the oil in the bleed control pressure chamber 73 is gradually discharged to the second drain port 74 and the oil leaks. At this time, the spool 82 is
And the control orifice 83 is gradually closed. Then, the spool 82 is moved to the sheet member 71.
When the control orifice 83 abuts, a part of the control orifice 83 is closed by the valve portion 822 of the spool 82, and the inner peripheral surface opening of the control orifice 83 is formed as a small-diameter second orifice 830.

Therefore, the oil is supplied from the control orifice 83 to the second
The gas enters the bleed control pressure chamber 73 through the orifice 830, and is further discharged to the second drain port 90 through the bleed hole 711. Therefore, even if the spool 82 moves toward the sheet member 71 and comes into contact therewith, the amount of oil leaked from the second drain port 90 is reduced because it passes through the small-diameter second orifice 830, and ,
Particularly, in forming the second orifice 830, since the sheet member 71 is not particularly processed, an inexpensive electromagnetic control valve with a small amount of leakage can be provided.

The stator core 11 of the solenoid 10 has an inner annular portion 11b formed on the yoke 14. Of these, a clearance H on one side in the radial direction with respect to the inner peripheral surface of the stator core of the annular portion 11b, The relationship with the interpolated length L that protrudes from the projection is such that the clearance on one side is
In the range of 0.05 to 0.25 mm, the clearance between the annular portion with respect to one side in the radial direction with respect to the inner peripheral surface of the stator and the insertion length with respect to the axial direction is approximately 1:40 to 6
Since it is in the range of 0, it is possible to sufficiently secure the magnetic flux flowing from the inner annular portion 14b to the stator core 11.

That is, when the solenoid 10 is assembled, even if the fitting of the stator core 11 with the inner annular portion 14b of the yoke 14 is loosened, the insertion length L is increased, so that the stator core 11 is moved from the yoke 14 to the stator core 11. A sufficient flowing magnetic flux can be secured.

The configuration of the solenoid 10 is not limited to the configuration of the control valve 30 shown in FIG. 1 but the configuration of the control valve 60 according to the second embodiment shown in FIG. 7 or the configuration shown in FIG. Third
May be a control valve 80 in the form of
In addition, regardless of the presence or absence of the seat members 21, 51, 71, the present invention can be applied to any device configured as an electromagnetic control valve.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an electromagnetic control valve according to a first embodiment of the present invention.

FIG. 2 is an enlarged view showing a valve chamber in FIG.

FIG. 3 is an enlarged view showing a second orifice.

FIG. 4 is a view taken in the direction of arrow A in FIG. 3;

5 is an operation diagram showing a state in which a spool in the electromagnetic control valve of FIG. 1 has moved.

FIG. 6 is an enlarged view showing the valve chamber in FIG.

FIG. 7 is a front sectional view showing an electromagnetic control valve according to a second embodiment of the present invention.

FIG. 8 is an enlarged view showing a second orifice of the electromagnetic control valve in FIG.

FIG. 9 is a front sectional view showing an electromagnetic control valve according to a third embodiment of the present invention.

FIG. 10 is an enlarged view showing a valve chamber of the electromagnetic control valve of FIG. 9;

11 is an enlarged view showing a state in which a spool in the solenoid valve of FIG. 10 has moved.

FIG. 12 is a view taken in the direction of arrow B in FIG. 11;

FIG. 13 is an enlarged view of a main part in FIG. 1;

FIG. 14 is a graph showing the relationship between the radial clearance between the stator core and the annular portion of the yoke in FIG. 1 and the insertion length.

[Explanation of symbols]

 1, 5, 7 ... Electromagnetic control valve 10 ... Solenoid 11 ... Stator core 11b ... Second stator 12 ... Moving core 121 ... Bleed valve 13 ... Coil 14 ... Yoke 14b ... Inner ring part 20, 50, 70 ... Valve chamber 21, 51, 71: sheet member 211, 521, 711: bleed hole (oil passage) 214, 542, 830: second orifice 23, 53, 73: bleed control pressure chamber (pressure control chamber) 24: drain hole 30, 60, 80 ... control valves 32, 62, 82 ... spools 33, 64, 83 ... control orifices 35, 65, 85 ... supply ports 36, 66, 86 ... output ports 37, 67, 87 ... drain ports 39, 63, 89 ... second supply ports 40, 69, 90 ... second drain port 52 ... first sheet part 54 ... second sheet part 621 ... oil flow path (Flow path) H One-side clearance in radial direction L Insertion length

Claims (6)

[Claims] 1. A spool for switching flow from a supply port to an output port and flow from an output port to a drain port, a solenoid having a moving core slidably disposed by electromagnetic attraction, and the moving core. A seat member having an oil passage formed so as to be openable and closable by a valve body at a distal end portion thereof, and a pressure control chamber formed between the seat member and the spool end face,
An electromagnetic control valve having a valve chamber composed of two ports, a second supply port including a control orifice for adjusting oil flowing into the pressure control chamber, and a second drain port discharging oil in the pressure control chamber. A second orifice portion having a smaller diameter than the control orifice is formed by the spool and the sheet member between the control orifice and the pressure control chamber in a state where the spool is in contact with the sheet member. An electromagnetic control valve, characterized in that: 2. The control orifice is disposed near the seat member, the second orifice is formed in the seat member, and one end is connected to the pressure control chamber and the other end is connected to the control orifice. The electromagnetic control valve according to claim 1, wherein the electromagnetic control valve is formed in a slit shape. 3. A control device according to claim 1, wherein said control orifice is disposed at a position separated from said sheet member, said first or second sheet member being disposed on said solenoid side and said second orifice being disposed on said spool side. Wherein the control orifice is connected to the pressure control chamber via a flow passage formed in the spool, and the second orifice is
The electromagnetic control valve according to claim 1, wherein a slit is formed in the second sheet member so as to face the flow path. 4. A spool for switching between a flow from a supply port to an output port and a flow from an output port to a drain port, a solenoid having a moving core slidably disposed by electromagnetic attraction, and the moving. A pressure control chamber formed between the seat member and the spool end surface, the pressure control chamber being configured to include a sheet member having an oil passage formed to be openable and closable by a valve body at a tip end portion of the core; An electromagnetic control valve having a valve chamber including two ports, a second supply port including a control orifice for adjusting oil flowing into a chamber and a second drain port discharging oil in the pressure control chamber, When the spool closes a part of the control orifice in a state where the spool is in contact with the sheet member, the control orifice is moved to the control orifice. Electromagnetic control valve, wherein the second orifice of smaller diameter than office is formed. 5. A control valve having a built-in spool for switching between a flow from a supply port to an output port and a flow from an output port to a drain port, a hollow coil for generating a magnetic field when energized, and an internal coil. An electromagnetic control valve formed by joining a yoke to be fitted, a stator core to be internally fitted to the coil, and a solenoid having a moving core slidably fitted to the stator core, wherein the yoke is formed of the stator core. At the rear side on the opposite side of the spool, there is provided an inner annular portion which is internally fitted with a predetermined clearance with respect to the inner peripheral surface of the stator core and is axially inserted at a predetermined length from the rear end surface of the stator core. The inner annular portion is formed so as to secure a predetermined magnetic flux. Electromagnetic control valve, characterized in that the inner 挿長 Sato is fitted in the stator core to maintain the value set to indicate correlation to the lance in the axial direction. 6. The set numerical value is such that the clearance between one side in the radial direction of the annular portion with respect to the inner peripheral surface of the stator core and the insertion length in the axial direction are 0.05 to 0.5. 6. The method according to claim 5, wherein the distance is about 1:40 to 60 in the range of 25 mm.
Electromagnetic control valve as described.